CASE 111: A TERM NEONATE WITH RESPIRATORY DISTRESS
You are asked to attend the delivery of a baby weighing 3500 g who is at 40 weeks’ gestation. The mother is 35-years-old and G2P1. Delivery was by emergency cesarean delivery for fetal distress and late decelerations. Rupture of maternal membranes occurred 28 hours before delivery. Thick meconium-stained amniotic fluid was noted at that time. The mother received four doses of ampicillin before delivery. All prenatal ultrasounds were normal.
SELECT THE ONE BEST ANSWER
1. The best initial airway management of this neonate is to
(A) suction the oropharynx and nasopharynx before delivery of the shoulders
(B) suction the oropharynx and nasopharynx after delivery
(C) immediately take the neonate to the warming table for vigorous drying before any suctioning of the airway
(D) give blow-by oxygen and observe before any suctioning of the airway
(E) not allow the vigorous neonate to cry and intubate the neonate before any airway suctioning
2. The cesarean section delivery is uneventful. Shortly after birth, the baby has subcostal and intercostal retractions. The oxygen (O2) saturation in room air is 72%. The baby is placed under a 60% O2 hood with improvement in O2saturation to 95%. Which is the least likely diagnosis?
(A) sepsis
(B) transient tachypnea of the newborn
(C) phrenic nerve injury
(D) group B streptococcal pneumonia
(E) meconium aspiration
3. Following the scenario in question 2, which would not be indicated at this time?
(A) chest radiograph
(B) blood culture and complete blood count (CBC) with differential leukocyte count
(C) blood glucose
(D) chest tube thoracostomy
(E) hyperoxia test
4. Following the scenario in question 2 what should be included in the management of the patient at this time?
(A) giving nothing by mouth (NPO) and starting intravenous (IV) maintenance fluids
(B) starting antibiotics
(C) monitoring O2 saturation
(D) monitoring blood glucose concentration
(E) all of the above
5. The arterial blood gas (ABG) determination on 60% O2 delivered by hood reveals a pH 7.35, PaO2 45, Po2 52. What is/are the likely diagnosis/diagnoses based on these ABG data and the chest radiograph seen in Figure 111-1?
(A) pneumonia, probably bacterial
(B) meconium aspiration pneumonitis
(C) transient tachypnea of the newborn (TTN)
(D) transposition of the great arteries
(E) A or B
FIGURE 111-1.
6. After the blood gas result was obtained, the fraction of inspired oxygen (Fio2) was increased to 1.0; the O2 saturation was still in the 88-92% range. The baby was intubated and mechanically ventilated with an Fio2 1.0, peak inspiratory pressure (PIP) 25, positive end-expiratory pressure (PEEP) 5, rate 60, I-time 0.4. The ABG values were pH 7.37, partial pressure of carbon dioxide (Pco2) 40, partial pressure of oxygen (PaO2) 50, mean airway pressure (MAP) 13. What other treatment do you want to initiate at this time?
(A) surfactant
(B) prostaglandins
(C) nitrous oxide
(D) furosemide
(E) dobutamine
7. What is the most important next diagnostic test?
(A) echocardiography
(B) cardiac catheterization
(C) head ultrasound
(D) computed tomography of the chest
(E) no additional diagnostic test is needed
8. An echocardiogram shows a bidirectional shunt at the atrial level, a tricuspid jet of 4.0, bulging of the interatrial septum toward the left side, normal valves, pulmonary veins and aorta, and good myocardial function. These findings are diagnostic of
(A) pulmonary hypertension
(B) cyanotic heart disease
(C) idiopathic hypertrophic subaortic stenosis (IHSS)
(D) congenital cardiomyopathy
(E) none of the above
9. What factor at birth decreases the pulmonary vascular resistance?
(A) cold stimulus
(B) decrease in alveolar Po2
(C) increase in partial pressure of alveolar CO2
(D) leukotrienes
(E) mechanical distension of the lungs
10. All of the following may play a role in the management of persistent pulmonary hypertension (PPHN) except
(A) inotropes
(B) milrinone
(C) furosemide
(D) inhaled nitric oxide (NO)
(E) sildenafil
11. Which of the following factors can lead to pulmonary hypertension?
(A) sepsis
(B) meconium aspiration
(C) respiratory distress syndrome (RDS)
(D) diaphragmatic hernia
(E) all of the above
12. The ventilatory settings are increased to PIP 35, PEEP 5, rate 60, Fio2 1.0, and I-time 0.4. The MAP is 15. The ABGs on these settings are pH 7.40, Pco2 38, and Pao2 50. What is the oxygenation index of this patient?
(A) 3%
(B) 30%
(C) 33%
(D) 53%
(E) 60%
13. Because the PIP is 35 and the Pao2 is still 50, you are worried about barotrauma and change the ventilator to high-frequency oscillatory ventilation (HFOV). The ABGs on the HFOV at an Fio2 1.0, MAP 17, ΔP 35, Hz 10, and 20 ppm NO are pH 7.41, Pco2 35, and Pao2 200. Pre- and postductal O2 saturation is 100%. The baby does well for a few hours and then desaturates to the 60% range. The heart rate drops to 80 and the mean blood pressure (BP) is 28. Immediate management includes all of the following except
(A) check endotracheal tube (ET) placement
(B) check for pneumothorax
(C) give intravascular volume expansion
(D) give surfactant
(E) all of the above
14. The patient stabilizes after an IV fluid bolus and an increase in ventilatory settings. In the next few hours, the baby is very labile and requires frequent volume pushes to keep the mean BP in the 60 mm Hg range. Dopamine is being administered at 20 μg/kg per minute. The baby desaturates when the mean BP is less than 50 mm Hg. ABG values on HFOV, Fio2 1.0, MAP 20, ΔP 40, Hz 10 are pH 7.45, Pco2 32, and Pao2 48. A chest radiograph shows a 10-rib expansion and no air leak. The cardiothymic shadow is normal. Management at this time could include which of the following?
(A) increase the ventilatory settings
(B) ↑NO to 40 ppm
(C) prepare for extracorporeal membrane oxygenation (ECMO)
(D) all of the above
(E) none of the above
15. Which medication used by the mother during the last trimester of her pregnancy is most likely to cause PPHN in her newborn?
(A) phenobarbital
(B) captopril
(C) aspirin
(D) bupropion
(E) levothyroxine
ANSWERS
1. (A) Meconium is composed of intestinal cells, the solid components of amniotic fluid, and intestinal secretions. The neonate’s first several bowel movements are meconium. Stressors to the fetus, such as maternal preeclampsia or placental insufficiency, may cause the fetus to pass meconium in utero. Reflexively, the fetus will also make gasping movements, which may result in aspiration of the meconium. Besides decreasing the antibacterial quality of the amniotic fluid, predisposing the fetus to infection, meconium has negative effects on the fetal respiratory system. Airway obstruction by the particulate meconium, disruption of the surfactant layer, and chemical pneumonitis are all deleterious effects of meconium. Meconium staining of amniotic fluid occurs in 10-15% of deliveries. Meconium aspiration occurs in 1% of these cases. Whenever meconium is noted in amniotic fluid, whether it is thin or thick, obstetricians should suction the infant’s oropharynx and nasopharynx before delivery of the shoulders. Babies that are vigorous at birth will not benefit from intubation and suctioning.
2. (C) Any of these can cause respiratory distress in a newborn. Babies with transient tachypnea generally do not have retractions. Phrenic nerve injury, leading to diaphragm dysfunction, is usually due to a brachial plexus injury (BPI); in this vignette there is no history of a large-for-gestational-age infant, instrumentation at delivery (forceps/vacuum), or shoulder dystocia, all of which are risk factors for BPIs.
3. (D) A chest radiograph, evaluation for sepsis, and evaluation for hypoglycemia are all appropriate in this scenario. To rule out congenital cyanotic heart disease, a hyperoxia test is appropriate. To perform a hyperoxia test, obtain a baseline right radial (preductal) arterial blood gas. Next, the patient should be in a head hood with 100% O2 for 15 minutes, after which another ABG is obtained. If the Pao2 rises above 150 mm Hg, then cyanotic heart disease has been ruled out. Meconium aspiration is associated with an increased risk for pneumothorax but without any clinical signs that would indicate a pneumothorax such as unequal air entry into the lungs, a displaced apical beat, or findings on transillumination, a chest tube thoracostomy is not indicated.
4. (E) Any newborn baby with respiratory distress should have a chest radiograph. A sepsis workup should also be done, and the patient should be started on antibiotics, especially because there is a history of prolonged rupture of membranes that places this child at a higher risk for infection. Hypoglycemia can present with a wide range of nonspecific symptoms. In a term baby with respiratory distress, the aim is to maintain the O2 saturation at 96-100%.
5. (E) The chest radiograph shows bilateral scattered infiltrates. The cardiothymic shadow is normal. This fits best with a picture of pneumonitis, etiology uncertain. TTN usually is associated with perihilar streaking and fluid in the fissures.
6. (A) Surfactant administration is recommended for meconium aspiration. Meconium inactivates native surfactant and there is decreased surfactant production following alveolar injury. Inhaled NO is a pulmonary vasodilator. Meconium aspiration syndrome is associated with persistent pulmonary hypertension (PPHN) in many cases. If you are in a hospital where echocardiography cannot be done to rule out cyanotic heart disease, and despite high ventilator settings and other supportive measures the Pao2 is low, it is appropriate to start a prostaglandin drip to maintain a patent ductus arteriosus (PDA). Dobutamine and nitrous oxide may be needed if the neonate’s condition continues to deteriorate.
7. (A) Before making the diagnosis of PPHN as the cause of hypoxemia/low Pao2 in a term baby with respiratory distress, an echocardiogram should be done to rule out cyanotic congenital heart disease.
8. (A) After birth, the neonate experiences a rapid decrease in pulmonary vascular resistance. In persistent PPHN, pulmonary pressures remain higher than systemic pressures, resulting in right-to-left shunting at the ductal or atrial level and subsequent hypoxemic respiratory failure. In this patient, bidirectional shunting at the atrial level and bulging of the interatrial septum to the left indicates a high pulmonary pressure compared with systemic pressure.
PPHN generally occurs in a full-term or postterm infant on day of life 1 with hypoxia and cyanosis. The patient can be very labile. The Pao2 can increase from 45 to 200 without any change in therapy. If the shunt is at the ductal level, there will be a difference in the pre- and postductal blood O2 saturation. This difference in pre- and postductal O2 blood saturation is not seen if the shunt is at the atrial level or intrapulmonary.
9. (E) Pulmonary vascular resistance is high in the normal fetus because of several factors: low fetal Pao2 (normal Pao2 of fetus is 30/mm Hg), high fetal Paco2, increased constrictor stimuli like leukotrienes and endothelin, and lack of a dilator stimulus like NO. At birth, mechanical distention of the lung, an increase in Pao2, a decrease in Paco2, and an increase in pH cause decreased pulmonary vascular resistance. Mechanical distention of the lung helps pulmonary vasodilation both mechanically and by the production of endogenous vasodilators.
10. (C) Inotropes are used in PPHN to increase the systemic BP so that right-to-left shunting will reverse. Increasing ventilator settings and the MAP will improve oxygenation. Studies in animals have shown that respiratory and metabolic alkalosis lowers pulmonary vascular resistance. Inhaled NO has a rapid and potent vasodilatory effect. Inhaled NO is contraindicated in congenital heart disease that depends on right-to-left shunting across the ductus arteriosus. Therefore, an echocardiogram is essential before starting inhaled NO. Milrinone decreases pulmonary artery resistance and may work additively with inhaled NO. There is no role for furosemide in PPHN. IV sildenafil is a selective pulmonary vasodilator but may cause hypotension and worsen oxygenation when used in conjunction with inhaled NO.
11. (E) The normal transition from intrauterine to extrauterine life requires a precipitous drop in pulmonary vascular resistance. Any factor that impairs this normal transition can cause PPHN. The causes of PPHN can be divided into three categories: parenchymal lung disease, idiopathic, and pulmonary hypoplasia. Parenchymal lung disease can be caused by several factors including meconium aspiration syndrome, RDS, and sepsis. Pulmonary hypoplasia can be caused by factors like a congenital diaphragmatic hernia.
12. (B) The oxygenation index (OI) is a commonly used calculation to determine the severity of pulmonary hypertension. OI >25 generally is used as a criterion to begin inhaled NO. Worsening (increasing) OI may point toward the need for ECMO.
Oxygenation Index (OI) = [Mean Airway Pressure
× Fio2 × 100]/Pao2.
In this patient, OI = [15 × 1.0 × 100]/50 = 30%.
13. (D) When a patient acutely decompensates, mechanical causes like ET placement, the presence or absence of pneumothorax, or mechanical factors related to the ventilator should be checked. If mechanical factors are noncontributory, the patient likely has high pulmonary pressure. Any time systemic pressures decreases, there will be right-to-left shunting. Administration of intravascular volume expansion is appropriate to increase the systemic pressure. Surfactant will not help.
14. (D) The dose approved by the Food and Drug Administration (FDA) for inhaled NO is 20 ppm. There is a very small subset of patients that do not respond to 20 ppm but respond to 40 ppm. The OI of the patient at this time is 41%. An OI > 40% is predictive of 80% mortality. If the OI for the next few hours remains high, this patient will be a candidate for ECMO.
15. (C) Constriction of the fetal ductus arteriosus may lead to PPHN. Of the medications listed, only aspirin does this. Other nonsteroidal anti-inflammatory drugs can also do this.
SUGGESTED READING
Hany A. Respiratory disorders in the newborn: identification and diagnosis. Pediatr Rev. 2004;25:201-207.
Konduri GG. New approaches for persistent pulmonary hypertension of newborn. Clin Perinatol. 2004;31:591-611.
Steinhorn RH, Farrow KN. Pulmonary hypertension in the neonate. NeoReviews. 2007;8:e14-e21.
CASE 112: A PREMATURE NEONATE WITH RESPIRATORY DISTRESS SYNDROME AND NECROTIZING ENTEROCOLITIS
A 650-g baby at 26 weeks’ gestation is born to a 20-year-old G2P1 mother by vaginal delivery. Mom presented in preterm labor 6 hours before delivery. The maternal membranes were intact; Mom had no fever. The mother received one dose of betamethasone and one dose of penicillin 4 hours before delivery. Serologic tests for syphilis, hepatitis B surface antigen, and human immunodeficiency virus (HIV) were all negative. The baby is depressed at birth with a heart rate of 100 beats/ minute and is dusky. The respiratory effort is poor. The patient is suctioned and positive pressure ventilation is given for about 1 minute with improvement in heart rate and color. However, the respiratory effort remains poor. The baby becomes dusky each time bagging is stopped, at which time you decide to intubate with a size 2.5 endotracheal tube (ET). The ET is secured with tape and bagging is continued with the ET in place. The color and heart rate improve. The baby now has some spontaneous respiratory effort and begins to move. The baby is taken to the special care nursery. The Apgar scores are 3 and 7 at 1 and 5 minutes, respectively.
SELECT THE ONE BEST ANSWER
1. Administration of steroids to the mother probably helped the baby
(A) yes
(B) no
2. What are the problems that you anticipate in the first 24 hours in this premature baby?
(A) fluid/electrolyte imbalance
(B) RDS
(C) sepsis
(D) hypoglycemia
(E) all of the above
3. After admission to the neonatal intensive care unit (NICU), the baby is put on a ventilator with the following settings: Fio2 of 1.0, PIP of 20, PEEP of 5, rate of 40, and I-time of 0.3. The O2 saturation is in the mid-90% range. The perfusion is good, the mean BP is 28, the heart rate is 140/minute, and the respiratory rate is 40-50/minute. The baby has mild to moderate subcostal retractions. What is the differential diagnosis of the respiratory distress?
(A) respiratory distress syndrome (RDS)
(B) sepsis
(C) hypoglycemia
(D) A and B
(E) A, B, and C
4. What should be included in the initial management?
(A) surfactant administration
(B) insertion of umbilical lines
(C) sepsis workup and antibiotic administration
(D) IV maintenance fluids and a chest radiograph
(E) all of the above
5. All of the following monitoring is required except
(A) ABGs and O2 saturation
(B) electrolytes, calcium (Ca), and glucose
(C) BP
(D) bilirubin
(E) all of the above (no exception)
6. The baby is under a radiant warmer and receiving a steady rate of IV fluids. The first set of serum electrolytes at 12 hours of age includes a sodium (Na) 150 mEq/mL, potassium (K) 5.8 mEq/mL, chloride (Cl) 108 mEq/ mL, and carbon dioxide (CO2) 18. What do you want to do?
(A) increase fluid administration
(B) decrease fluid administration
(C) increase Na concentration in the administered fluids
(D) A and C
(E) make no change and repeat electrolytes in 12 hours
7. On day 2 of life the patient’s weight is 550 g and the urine output is 1 mL/kg per hour. The ventilatory settings are Fio2 40%, PIP 18, PEEP 5, I-time 0.3, and a rate of 40/minute. An ABG shows a pH of 7.38, Paco2 of 38, and a Pao2 of 95. Serum electrolytes reveal Na 152 mEq/mL, K 5.6 mEq/mL, Cl 110 mEq/mL, CO2 18, Ca of 6.5 mEq/mL, and bilirubin of 4.0 mg/dL. What is the next step?
(A) increase fluid administration rate and add Ca to fluids
(B) increase fluid administration rate and add Ca and K to fluids
(C) make ventilatory setting changes
(D) start hyperalimentation
(E) A, C, and D
8. On day 3 of life the patient’s weight is 570 g and the urine output is 3 mL/kg per hour. The ventilatory settings are Fio2 0.3, PIP 16, PEEP 5, I-time 0.3, and a rate of 30/minute. Determination of serum electrolytes reveals Na 148 mEq/mL, K 3.5 mEq/mL, Cl 108 mEq/mL, CO2 18, and Ca 7.5 mEq/mL. What is the next step?
(A) increase IV fluids and add K
(B) administer IV fluids at the same rate and add K
(C) increase IV fluids but do not add K
(D) no change
(E) decrease total fluids
9. On day 3 of life, the ventilatory settings have increased to Fio2 0.5, PIP 20, PEEP 6, and a rate of 50/minute. On examination, there is an active precordium. The peripheral pulses are full; the BP is 35/16, and, on auscultation, there is a grade II/VI systolic murmur. The hematocrit is 32%. An echocardiogram confirms your diagnosis of a PDA. The best initial management of this condition is
(A) prostaglandins
(B) indomethacin
(C) furosemide
(D) increase IV fluids
(E) decrease the Fio2
10. Which condition is most often associated with PDA?
(A) congenital syphilis
(B) congenital varicella
(C) congenital cytomegalovirus
(D) congenital rubella
(E) congenital parvovirus B19
11. IV indomethacin could adversely affect which of the following?
(A) urine output
(B) serum sodium
(C) serum creatinine
(D) A, B, and C
(E) none of the above
12. After three doses of IV indomethacin, the patient improves. The ventilatory settings are Fio2 30%, PIP 16, PEEP 5, and a rate of 30/minute. No murmur is heard. You start nasogastric feedings. After 3-4 days, the patient develops abdominal distention and has increased residual feeds. On abdominal examination the baby has some guarding. All would be appropriate actions except
(A) make the patient NPO and institute gastric suction
(B) order an abdominal radiograph
(C) order a sepsis workup
(D) start antibiotics
(E) change the enteral feeds to an elemental formula containing a probiotic
13. The patient’s abdominal radiographs can be seen in Figure 112-1. What is the next step?
(A) order serial abdominal radiographs
(B) monitor the platelet count
(C) monitor the urine output closely
(D) monitor ABGs
(E) all of the above
FIGURE 112-1.
14. The patient in Figure 112-2 requires surgery. What is an absolute indication for surgery in a patient with necrotizing enterocolitis (NEC)?
(A) free air
(B) fixed loop sign
(C) intractable thrombocytopenia
(D) intractable acidosis
(E) signs of peritonitis
FIGURE 112-2.
15. The patient’s abdominal radiograph improves during the next few days. The platelet count is stable. Which is the most likely complication of NEC?
(A) intestinal stricture
(B) chronic constipation
(C) neurodevelopmental problems
(D) increased risk of food allergies
(E) increased risk of irritable bowel syndrome
16. What routine monitoring should be done in the first week of life in all premature babies?
(A) a head ultrasound
(B) an echocardiogram
(C) cardiac catheterization
(D) an ophthalmology examination
(E) A, B, and D
ANSWERS
1. (B) Antenatal corticosteroids, betamethasone, or dexamethasone decrease morbidity from respiratory distress, NEC, and intraventricular hemorrhage. Steroids are most effective if delivery occurs 48 hours to 7 days after administration, but some beneficial effect has been seen as early as 12 hours after the first dose.
2. (E) Premature babies lighter than 750 g and less than 28 weeks’ gestation have a very high insensible water loss. The insensible water loss is increased under a radiant warmer, in low ambient humidity, and during phototherapy. RDS is caused by surfactant deficiency. Surfactant is produced by type II alveolar cells. Surfactant decreases surface tension, thus decreasing the pressure required to stabilize the alveolus. Sepsis should always be considered in a sick newborn. Hypo- or hyperglycemia can both occur.
3. (E) Babies with surfactant deficiency have stiff lungs with decreased compliance; compliance of the chest wall in premature babies is high. In surfactant deficiency, a higher pressure is needed to open the alveoli; this manifests as retractions. In a premature baby, RDS or surfactant deficiency is the most likely cause of respiratory distress. Sepsis should always be considered in a baby with respiratory distress. Hypoglycemia can also present as respiratory distress.
4. (E) Surfactant is 90% lipid and 10% protein. Surfactant proteins A, B, C, and D are important for dispersion of surfactant. Exogenous surfactant is administered via an endotracheal tube. Synthetic and natural surfactants are available.
Two different strategies are used for administration of exogenous surfactant. Prophylactic surfactant may be given within 30 minutes after birth; rescue surfactant is given once the diagnosis of RDS is made by radiologic and clinical criteria. Umbilical lines are placed in premature babies for monitoring blood gases and for IV access. The chest radiograph in RDS shows a reticulogranular pattern with air bronchograms (Figure 112-3A). Severe respiratory distress appears as a “whiteout” (Figure 112-3B). Because the chest radiograph appearance of group B streptococcal pneumonia and surfactant deficiency are similar, any premature baby with respiratory distress should have a workup for possible sepsis, and antibiotic therapy should be initiated.
FIGURE 112-3A. Reticulogranular pattern with air bronchograms.
FIGURE 112-3B. Chest radiograph showing “whiteout” in severe respiratory distress syndrome.
5. (E) A normal ABG determination for a premature baby on day 1 of life would be pH higher than 7.25, Paco2 of 45-55 mm Hg, and a Pao2 >50 mm Hg. The normal cord blood glucose is 80% of the mother’s glucose but reaches a nadir at about 2 hours of age but is less than 45 mg/dL. A general rule of thumb is that the mean BP is roughly the same as the gestational age. For this baby, a mean BP higher than 26 mm Hg is normal. Insensible water loss is inversely proportional to gestational age; that is, the more immature the baby, the higher the insensible water loss. Because premature babies lighter than 750 g have very high insensible water losses, the serum Na should be monitored closely and the fluid administration adjusted accordingly. The serum Ca of a neonate on day 1 of life is normally higher than that of the mother. Therefore, the patient does not need any Ca added to the IV fluids on day 1 of life. Babies lighter than 750 or 1000 g are sometimes placed on prophylactic phototherapy on day 1 of life. An O2 saturation in the high 80% to the low 90% range is acceptable on day 1 of life. NICUs have different standards for an acceptable O2 saturation at different times of a premature baby’s life, and thus these values may very slightly.
6. (A) A serum Na of 150 mEq/mL indicates that the insensible water loss was underestimated. One should increase the volume of administered fluids and continue to monitor serum electrolytes. The baby’s weight also should be monitored. It is necessary to monitor the serum glucose because the fluid volume being administered is increased. If the serum glucose is normal, D10W can be given. If the serum glucose is high, a change to D5W should be made as you increase the administered fluid volume. The baby should lose weight in the first few days. A weight loss of 1-3% per day is called physiologic dehydration and is desirable.
7. (E) The serum Na concentration is now 152 mEq/mL, so it would be appropriate to increase the total fluids being administered. Because the serum Ca is low, it would be appropriate to add Ca. Blood gases suggest overventilation, so it would be appropriate to adjust the ventilatory settings. Hyperalimentation is usually started in extremely low-birthweight babies on day 1-2 of life.
8. (A) Urine is the main avenue of K excretion. Once the urine output is good, K can be added to the IV fluids if the serum K is not high. Because the serum Na is still high, the rate of fluid administration should be increased. In premature babies lighter than 750 g that are not oliguric, hyperkalemia can occur. If a patient’s serum K is 7.5-8, one should not dismiss it as a laboratory error or secondary to hemolysis.
9. (B) The fetal ductus arteriosus (DA) is a normal structure in utero allowing blood to bypass the fetal pulmonary vascular bed and go directly to the descending aorta. The DA is kept patent by prostaglandin E2. Functional closure of the DA occurs at about 15 hours of life and is triggered by increasing Pao2. True anatomic closure of the DA, where reopening is not possible, may take several weeks. The clinical signs of PDA are widened pulse pressure, an active precordium, full or bounding pulses, and a pansystolic murmur. An echocardiogram and a chest radiograph should be obtained.
Excessive fluid administration has been associated with an increased incidence of PDA. Indomethacin, a prostaglandin inhibitor, is an effective treatment.
10. (D) Congenital infection with rubella has been classically associated with PDA. Myocarditis may be a feature of congenital syphilis, but usually one thinks of the typical rash associated with syphilis, snuffles, and bony abnormalities with regard to congenital syphilis. Congenital varicella syndrome is often associated with eye findings, microcephaly, fibrous scars, and limb hypoplasia. Congenital CMV infection often has periventricular intracranial calcifications, chorioretinitis, sensorineural hearing loss, and skin findings. Congenital parvovirus B19 may lead to hydrops fetalis in utero.
11. (D) Indomethacin is associated with vasoconstriction of other vessels including the cerebral, mesenteric, and renal vasculature. Renal function should be assessed before giving indomethacin. Urine output less than 1 mL/kg per hour or a serum creatinine more than 1.8 mg/dL is a contraindication to the use of indomethacin. Dilutional hyponatremia has also been reported.
12. (E) Abdominal distention and increased gastric residuals before feeding may be signs of NEC. The diagnosis of NEC is made by abdominal radiograph. Because infection plays a role in the pathogenesis of NEC, a sepsis workup should be done and the patient should be started on antibiotics.
13. (E) The abdominal radiograph is suggestive of pneumatosis intestinalis. There is no free air and no portal air. NEC is predominantly a disease of premature babies, although 10% of cases occur in term infants. Signs and symptoms of NEC vary and may include apnea and bradycardia, vomiting, increased residuals, abdominal distention, and heme-positive stools. The diagnostic hallmark of NEC is pneumatosis intestinalis or submucosal air on an abdominal radiograph. Once the radiographic diagnosis of NEC is made, serial abdominal radiographs should be done looking for free air. The platelet count should be monitored. A drastic drop in the platelet count is an ominous sign. Because patients can lose a large amount of fluid into the abdominal cavity (third spacing), urine output should be monitored closely. A patient with NEC may require large amounts of IV fluids. It is important to monitor ABGs. Intractable acidosis is an ominous sign. Recent studies have shown that early feeding with probiotics may decrease the incidence of NEC, but if NEC is already clinically suspected, the patient must be made NPO; there is no evidence that probiotics will help treat NEC.
14. (A) The patient in Figure 112-2 has free air in the abdomen, an absolute indication for surgery. Other findings such as the fixed loop sign, intractable thrombocytopenia, intractable acidosis, and signs of peritonitis are relative indicators used by surgeons to decide about the need for laparotomy. All these relative indications point to the possibility of necrotic intestine in the abdomen.
15. (A) Strictures happen in about 10% of patients following NEC. Sepsis at this point is related to physician interventions such as indwelling vascular catheters placed for prolonged hyperalimentation.
16. (A) Periventricular or intraventricular hemorrhage can occur in 20-30% of premature babies; 90% of the hemorrhages occur in the first 72 hours of life. Fifty percent of the hemorrhages are clinically silent; others may present with subtle clinical change. A catastrophic presentation with a bulging anterior fontanel, drop in hematocrit, metabolic acidosis, and hyperglycemia can also occur. All premature babies lighter than 1500 g or less than 32-34 weeks’ gestation should have a first ultrasound of the head at day 3-5 of life, a second at day 7-10 of life, and subsequent ultrasounds based on these early results.
Intraventricular hemorrhages are classified as follows:
|
Grade I |
Subependymal bleed with no intraventricular extension |
|
Grade II |
Intraventricular hemorrhage with no ventricular dilation |
|
Grade III |
Intraventricular hemorrhage with ventricular dilation |
|
Grade IV |
Intraparenchymal bleed |
Retinopathy of prematurity (ROP) is a disorder of developing retinal blood vessels that continues to be a cause of major visual morbidity in premature infants. All premature infants should have an eye examination for ROP at about 4 weeks of age and continued periodic examinations until the retina is completely vascularized.
SUGGESTED READING
Henry MCW, Moss RL. Current issues in the management of necrotizing enterocolitis. Semin Perinatol. 2004;28;221-233
CASE 113: A TERM NEONATE WITH A HISTORY OF MATERNAL POLYHYDRAMNIOS
A 37-week gestational age, 2800-g baby girl is born to a 20-year-old primigravida by normal, spontaneous vaginal delivery. The pregnancy is significant for polyhydramnios. The baby’s Apgar scores are 8 and 9 at 1 and 5 minutes, respectively. The baby looks good, is pink on room air, in no distress, and is sent to the regular nursery.
SELECT THE ONE BEST ANSWER
1. Which of the following choices primarily controls the volume of amniotic fluid?
(A) fetal urine output
(B) family history
(C) placental factors
(D) gender of fetus
(E) fetal effluence from the gut
2. Which of the following statements about amniotic fluid is true?
(A) the swallowing ability of the fetus is a determinant of amniotic fluid volume
(B) at term the average volume of amniotic fluid is 3-5 L
(C) polyhydramnios is a risk factor for poor lung development
(D) maternal use of angiotensin-converting enzyme (ACE) inhibitors may lead to polyhydramnios
(E) Potter syndrome is associated with polyhydramnios
3. In the nursery, the neonate is fed a cow’s milk–based formula without any associated gagging or choking. At 15 hours of life, you are notified that this patient had one episode of bilious emesis. What is the next step in your evaluation?
(A) change to a soy-based formula
(B) continue feeds with close observation
(C) barium enema with anal manometry
(D) make the patient NPO
(E) abdominal and chest radiographs
4. All the following are associated with polyhydramnios except
(A) prune belly syndrome
(B) fetal hydrops with anasarca
(C) esophageal atresia
(D) duodenal atresia
(E) multiple gestation
5. What is the radiographic finding on this x-ray (Figure 113-1)?
(A) double bubble
(B) multiple air fluid levels
(C) nonspecific bowel gas pattern
(D) thumbprinting
(E) all of the above
FIGURE 113-1.
6. What is your diagnosis based on the above radiographic finding?
(A) tracheal stenosis
(B) esophageal atresia without a distal fistula
(C) “H”-type tracheoesophageal fistula
(D) choanal atresia
(E) duodenal atresia
7. What other organ systems or specific anomalies are associated with the above diagnosis?
(A) cardiac
(B) renal
(C) imperforate anus
(D) esophageal atresia
(E) all of the above
8. What chromosomal anomaly or disease syndrome is most commonly associated with duodenal atresia?
(A) trisomy 13
(B) Turner syndrome
(C) trisomy 21
(D) trisomy 18
(E) Klinefelter syndrome
9. Which statement is true of duodenal atresia?
(A) the pathophysiology is similar to that of other intestinal atresias
(B) abdominal distension is the most common presenting symptom
(C) duodenal atresia may present without bilious emesis
(D) duodenal atresia is not associated with an annular pancreas
(E) duodenal atresia is usually associated with oligohydramnios
10. Which contrast study is indicated emergently in a baby with bilious vomiting?
(A) upper gastrointestinal (GI) series
(B) lower GI series
(C) head ultrasound
(D) ultrasound of the pylorus
(E) computed tomography of the abdomen
ANSWERS
1. (A) The normal amount of amniotic fluid at birth is 0.5-2 L. The volume is primarily determined by fetal urine output. Oligohydramnios is defined as an amniotic fluid volume less than 500 mL. Polyhydramnios is an amniotic fluid volume more than 2 L at birth. Oligo- and polyhydramnios are both associated with fetal anomalies and poor perinatal outcome. Assessment of amniotic fluid volume is done ultrasonographically by calculation of an amniotic fluid index (AFI), a summation of amniotic fluid volume in each of the four quadrants of the uterus. Oligohydramnios is defined as an AFI <5 cm, and polyhydramnios is defined as an AFI >24 cm.
2. (A) Amniotic fluid contains proteins, carbohydrates, lipids and phospholipids, urea and electrolytes, all of which aid in the growth of the fetus. In the late stages of gestation, amniotic fluid consists mostly of fetal urine. In utero, the fetus “inhales” amniotic fluid, allowing proper growth of lung tissue. Amniotic fluid also serves as a cushion to prevent trauma to the developing fetus and as a barrier to infection. Decreased fetal swallowing may lead to polyhydramnios. At term, the volume of amniotic fluid averages between 800 and 1000 mL. Maternal use of ACE inhibitors and Potter syndrome are associated with oligohydramnios.
3. (D) Bilious emesis in a newborn is a worrisome event and signals an obstruction distal to the ampulla of Vater. The first step in management of these patients is to make the patient NPO. The type of formula fed to the infant is not related to bilious emesis. If the neonate has not had a bowel movement after 48 hours, one would suspect Hirschsprung disease, and a barium enema with anal manometry would be part of the evaluation.
4. (A) Conditions associated with polyhydramnios:
• Idiopathic (2 of 3)
• GI anomalies → duodenal and esophageal atresia
• Central nervous system (CNS) anomalies → anencephaly, primary muscle disease
• Hydrops → immune and nonimmune
• Maternal diabetes
• Multiple gestation
• Other fetal anomalies
Conditions associated with oligohydramnios:
• Postterm gestation
• Chronic fetal hypoxia associated with severe preeclampsia
• Premature rupture of membranes
• Maternal dehydration
• Monochorionic twin gestation
• Potter syndrome
• Prune belly syndrome (Eagle-Barrett syndrome)
• Maternal use of ACE inhibitors
• Other fetal anomalies → renal-developmental or obstructive malformations
5. (A) The classic double-bubble sign represents air in the stomach (proximal to the atresia) and air in the first part of the duodenum (distal to the atresia) (Figure 113-1).
6. (E) Suspicion of duodenal atresia in the neonate would lead one to order an abdominal radiograph to look for the classic double-bubble sign, representing air in the stomach (proximal to the atresia) and air in the first part of the duodenum (distal to the atresia). If the chest radiograph showed the nasogastric tube coiled in a blind pouch in the neck, it would indicate a tracheal atresia. The nasogastric tube coiling in a blind pouch with air seen in the GI tract indicates a distal tracheoesophageal fistula (TEF). If there was no abdominal gas, it would indicate esophageal atresia without a distal TEF. TEF occurs in 1:3000-1:4500 live births. Polyhydramnios is present in about a third of cases with esophageal atresia. Babies with TEF present with excessive oral secretions shortly after birth that may lead to coughing, choking, and respiratory distress. Infants with an “H”-type TEF generally do not present in the newborn period. Figure 113-2 shows the various types of TEF. The most common is esophageal atresia with distal TEF.
FIGURE 113-2.
7. (E)
8. (C) Down syndrome (trisomy 21) is most commonly associated with duodenal atresia. Patau syndrome (trisomy 13) has the worst prognosis of all the trisomies. Holoprosencephaly, polydactyly, rockerbottom feet, neural tube defects, and heart defects are also frequent clinical features. Edwards syndrome is caused by trisomy 18. Multiple organ systems are involved in this syndrome, including GI anomalies, but duodenal atresia is not a classic feature.
9. (C) Whereas other atresias of the small and large bowel are isolated anomalies caused by mesenteric vascular accidents during later stages of development, duodenal atresia results from the failure of the epithelial solid cord to recanalize (failure of vacuolization). Bilious emesis is the most common presenting symptom of duodenal atresia. Rarely, the duodenal atresia may be proximal to the ampulla of Vater resulting in no bilious emesis. Annular pancreas is not an uncommon associated finding with duodenal atresia. Duodenal atresia is commonly associated with polyhydramnios.
10. (A) Bilious vomiting in an infant suggests a diagnosis requiring surgical therapy until proven otherwise. Immediate evaluation for malrotation should be done. The procedure of choice for diagnosis of malrotation is an upper GI series looking for the position of the duodenojejunal junction.
SUGGESTED READING
Boyd RL. Polyhydramnios and oligohydramnios. Emedicine Web site. http://emedicine.medscape.com/article/975821-overview. Accessed July 20, 2009.
Karrer FM. Duodenal atresia. Emedicine Web site. http://emedicine.medscape.com/article/932917-overview. Accessed July 20, 2009.
Minkes RK. Congenital anomalies of the esophagus. Emedicine Web site. http://emedicine.medscape.com/article/934420-overview. Accessed July 20, 2009.
CASE 114: NEONATE OF A DIABETIC MOTHER
You are caring for a full-term 4300-g infant girl who was delivered by cesarean delivery due to a failed attempt at a vaginal delivery after a long and difficult labor. Maternal membranes were ruptured for 26 hours, but there were no signs of chorioamnionitis at delivery. The mother had received six doses of IV ampicillin since admission. Despite the cesarean delivery, a vacuum extraction of the neonate from the uterus was noted in the delivery record. The mother was 34-years-old with a history of poorly controlled diabetes that was diagnosed when she was 15 years old. She has been noncompliant with her insulin regimen, and her HbA1C on admission was 10.6%. The mother fed her baby cow’s milk-based formula immediately after birth.
SELECT THE ONE BEST ANSWER
1. What is the White classification of this mother?
(A) A2
(B) B
(C) C
(D) R
(E) F
2. What is the next step in the evaluation of this infant?
(A) CBC
(B) serum electrolytes
(C) blood glucose
(D) infant serum insulin levels
(E) liver function panel
3. As you examine this patient, you note tachypnea and nasal flaring. What is the most likely cause of this infant’s increased work of breathing?
(A) sepsis
(B) macrosomia
(C) pulmonary hypoplasia
(D) TTN
(E) congenital pneumonia
4. The patient’s respiratory status has improved after spending 24 hours in a head hood with 100% oxygen, and on day of life 2, the infant is on room air and no longer tachypneic. She has not passed meconium by 36 hours of life. The baby has nonbilious vomiting and the abdomen is distended. The examination is also remarkable for a patent anus without stool in the rectal vault and a 4-cm raised, well-circumscribed, firm lump on the head where the vacuum was applied that does not cross the midline. The differential diagnosis includes all of the following except
(A) meconium plug
(B) Hirschsprung disease
(C) small left colon syndrome
(D) congenital hypothyroidism
(E) conjugated hyperbilirubinemia
5. You order an abdominal x-ray that shows distended stool-filled loops of bowel with no signs of obstruction or free air. What is your next step in evaluating this patient?
(A) computed tomography of the abdomen
(B) upper GI with barium follow-through
(C) sweat test
(D) restart feedings slowly
(E) barium enema
6. On day of life 4, you notice that the patient is jaundiced. There is no other abnormality in the physical examination. The indirect bilirubin level is 9 mg/dL and the total serum bilirubin is 10.3 mg/dL. The least likely cause of jaundice in this patient is
(A) breakdown of fetal red blood cell mass
(B) breakdown of extravascular blood
(C) Crigler-Najjar syndrome, type I
(D) immaturity of liver enzyme function
(E) delayed passage of meconium
7. The mother tells you that the baby’s right arm, which you noted to be weak compared with the left arm on day of life 1, has not improved. When you examine the baby, you notice the right arm is limp and nonflexed. The Moro reflex is absent on the right side, but the grasp reflex is intact. All of the following are true about brachial plexus injuries except
(A) Erb palsy involves the upper trunk of the brachial plexus
(B) brachial plexus injury may cause respiratory distress
(C) lower brachial plexus injuries should prompt you to examine the pupils more closely
(D) most patients with brachial plexus injuries require surgical intervention
(E) Erb palsy is the most common brachial plexus injury
ANSWERS
1. (C) The White classification is used to ascertain risks to the fetus based on maternal age at onset of diabetes, duration of diabetes, and complications associated with diabetes. Class A1 and class A2 pertain to gestational diabetes (see Table 114-1).
2. (C) The most important initial evaluation in an infant born to a diabetic mother in the immediate postpartum period is to check the glucose level of the neonate. In utero, maternal glucose crosses the placenta, and, in response, the fetus; physiologic response is to create insulin. Once the neonate is delivered, the maternal glucose supply is interrupted but the fetal insulin effects are ongoing, causing neonatal hypoglycemia. Maternal insulin does not cross the placenta.
3. (D) This infant is at risk for TTN because she was born via cesarean delivery. It is postulated that infants born via cesarean delivery, not going through all the stages of labor, do not experience the catecholamine surge necessary to convert lung tissue ion channels from Cl- secretion to Na+ reabsorption. This leads to retained fluid in the lungs. Although there was prolonged rupture of membranes, the mother received adequate intrapartum antibiotic prophylaxis, and there were no signs of chorioamnionitis at delivery, making sepsis and congenital pneumonia less likely. Macrosomia itself does not predispose an infant to TTN. There was no mention of congenital diaphragmatic hernia, so lung hypoplasia is not likely a concern.
4. (E) Failure to pass meconium after 48 hours warrants immediate attention. Of all the choices, only conjugated hyperbilirubinemia would not present with delayed passage of stool. Meconium plug syndrome is common in infants born to diabetic mothers. This disease process occurs typically in term infants and is usually self-limited. Depressed or hypotonic neonates, including those whose mothers were receiving magnesium sulfate, are also at risk for meconium plug syndrome. Meconium ileus is seen in neonates with cystic fibrosis. Hirschsprung disease and small left colon syndrome have identical presentations, and radiographic findings but can be differentiated on rectal biopsy. In Hirschsprung disease, the biopsy shows no ganglions in the submucous or myenteric plexuses. Some consider small left colon syndrome pathognomonic of infants born to diabetic mothers. In addition to delayed passage of meconium, infants with congenital hypothyroidism may be jaundiced, have a large umbilical hernia, coarsened facies, a large anterior fontanelle, and hypotonia.
TABLE 114-1 Modified White’s Classification of Diabetes in Pregnancy
|
CLASS |
DESCRIPTION |
|
A |
Abnormal glucose tolerance test (GTT) at any age or of any duration treated only by diet therapy |
|
B |
Onset at age 20 years or older and duration of less than 10 years |
|
C |
Onset at age 10-19 years or duration of 10-19 years |
|
D |
Onset before 10 years of age, duration over 20 years, benign retinopathy, or hypertension (not preeclampsia) |
|
D1 |
Onset before age 10 years |
|
D2 |
Duration over 20 years |
|
D3 |
Calcification of vessels of the leg (macrovascular disease), formerly called Class E |
|
D4 |
Benign retinopathy (microvascular disease) |
|
D4 |
Hypertension (not preeclampsia) |
|
R |
Proliferative retinopathy or vitreous hemorrhage |
|
F |
Nephropathy with more than 500 mg/day proteinuria |
|
RF |
Criteria for both classes R and F |
|
G |
Many pregnancy failures |
|
H |
Evidence of arteriosclerotic heart disease |
|
T |
Prior renal transplantation |
|
Gestational Diabetics |
|
|
A1 |
Diet-controlled gestational diabetes |
|
A2 |
Insulin-treated gestational diabetes |
Classes B through T require insulin treatment. Adapted from Hare JW, White JP. Gestational diabetes and the White classification. Diabetes Care. 1980;3:394.
5. (E) The next step in the evaluation of delayed passage of meconium would be a barium enema with rectal biopsy. Because Hirschsprung disease and small left colon are indistinguishable radiographically, a rectal biopsy is necessary to differentiate between the two. A barium enema is also therapeutic for small left colon syndrome.
6. (C) All the choices may cause indirect hyperbilirubinemia in an infant at this age, but the level of unconjugated bilirubin found in Crigler-Najjar syndrome, type I would be much higher for an affected infant at day of life 4. The 4-cm lump previously described is a cephalohematoma (blood in the subperiosteum), which also can contribute to indirect hyperbilirubinemia.
Jaundice is a frequent issue in newborns. To understand why an infant is jaundiced, it is important to know the life cycle of bilirubin; there are three sites in this pathway where problems with bilirubin overload can occur: reticuloendothelial system (RES), liver, and GI system (see Figure 114-1).
FIGURE 114-1. Life cycle of bilirubin.
7. (D) Erb palsy involves the upper brachial plexus (C5-C7), and Klumpke palsy involves the lower brachial plexus (C8-T1). Erb palsy is more common. A patient with Erb palsy presents with the affected arm in a nonflexed position, assuming the classic waiter’s tip appearance; grasp is usually unaffected. An infant with Klumpke palsy holds the arm supinated, with the elbow bent and the wrist extended; the grasp is usually weak. More severe BPIs can lead to Horner syndrome (miosis in affected pupil) or diaphragmatic paralysis due to phrenic nerve injury. Most cases of BPI are selflimited and do not require surgical intervention. Risk factors for BPIs include large-for-gestationalage infants, shoulder dystocia, infants of diabetic mothers, and use of forceps or vacuum at delivery.
SUGGESTED READING
Gleason PF, Eddleman KA, Stone JL. Gastrointestinal disorders of the fetus. Clin Perinatol. 2000;27;901-920.
Maisels MJ. Neonatal jaundice. Pediatr Rev. 2006;27(12):443-453.
Nold JL, Geogieff MK. Infants of diabetic mothers. Pediatr Clin North Am. 2000;51(3):619-637.
Semel-Concepcion J. Neonatal brachial plexus palsies. Emedicine Web site. http://emedicine.medscape.com/article/317057-overview. Accessed July 20, 2009.
CASE 115: A NEONATE WITH A HISTORY OF MATERNAL GROUP B STREPTOCOCCAL COLONIZATION AND A REACTIVE RAPID PLASMA REAGIN TEST FOR SYPHILIS
A 3230-g infant was born to a 25-year-old G1P1 woman who had prenatal care starting in the third trimester. She had syphilis 2 years before that, according to her, had been treated with “shots.” Her screening test for syphilis (rapid plasma reagin [RPR]) was positive at a titer of 1:4 during this pregnancy. She has a history of cocaine abuse as well as a seizure disorder for which she takes phenytoin. She was found to be a vaginal carrier of group B beta-hemolytic streptococcus. On admission, she was in active labor and delivered the baby before receiving prophylactic intrapartum penicillin. The Apgar scores were 8 and 9 at 1 and 5 minutes of life, respectively.
SELECT THE ONE BEST ANSWER
1. Which is the best way to assess active syphilis in the mother?
(A) repeat RPR test
(B) VDRL (Venereal Disease Research laboratory) test
(C) culture of vaginal secretions
(D) FTA-ABS (fluorescent treponemal antibody absorption)
(E) A or B
2. Which statement is most accurate regarding a neonate with congenital syphilis?
(A) congenitally infected neonates asymptomatic at birth will most likely remain asymptomatic
(B) a neonatal RPR titer 4 times higher than the mother is indicative of congenital syphilis
(C) a twofold decrease in maternal RPR titer after treatment for syphilia is indicative of successful therapy
(D) Jarisch-Herxheimer reactions are common in neonates after treatment for congenitally acquired syphilis
(E) IV ceftriaxone is the treatment of choice in congenital syphilis
3. Which of these is least likely to be a manifestation of congenitally acquired syphilis?
(A) hemolytic anemia
(B) pseudoparalysis of Parrot
(C) snuffles
(D) patent ductus arteriosus
(E) periostitis and osteochondritis
4. Maternal cocaine use during pregnancy has been associated with which of the following?
(A) gastroschisis
(B) LGA (large for gestational age) babies
(C) increased incidence of Wilms tumor in children
(D) neural tube defects
(E) Ebstein anomaly
5. A medical student following this baby with you asks if the baby is at risk for neonatal abstinence syndrome. Which drug is most commonly associated with neonatal abstinence syndrome?
(A) heroin
(B) marijuana
(C) phencyclidine (PCP)
(D) cocaine
(E) tobacco
6. Anticonvulsant embryopathy has many features in common with fetal alcohol syndrome. Both have the following in common except
(A) hypertelorism
(B) atrial septal defect
(C) fingernail defects
(D) broad nasal bridge
(E) small for gestational age (SGA) at delivery
7. Infants born to women taking anticonvulsants are most likely at risk for complications due to decreased stores/function of which vitamin?
(A) C
(B) A
(C) K
(D) E
(E) D
8. What is the drug of choice for intrapartum antibiotic prophylaxis against group B streptococcus (GBS) if the mother is known to react to penicillin with anaphylaxis?
(A) vancomycin
(B) cefazolin
(C) clindamycin
(D) ceftriaxone
(E) levofloxacin
9. Which is a true statement regarding intrapartum antibiotic prophylaxis to prevent GBS disease?
(A) since the implementation of consensus guidelines for intrapartum antibiotic prophylaxis, there has been a significant decrease in the incidence of late-onset GBS disease
(B) asymptomatic babies born at greater than 35 weeks of gestation to mothers who have received 4 or more hours of intrapartum penicillin or ampicillin need no further evaluation or therapy for GBS sepsis if the baby appears to be clinically well
(C) asymptomatic babies born at greater than 35 weeks of gestation to mothers who have received 4 or more hours of intrapartum antibiotic prophylaxis need only limited further evaluation for GBS sepsis consisting of a CBC and blood culture
(D) ampicillin is not an appropriate first-line antibiotic for intrapartum anti-GBS prophylaxis
(E) since the implementation of consensus guidelines for intrapartum antibiotic prophylaxis, there has been a significant decrease in the incidence of neonatal sepsis due to other organisms
10. Late-onset GBS infection in neonates would most likely present as
(A) hepatitis
(B) NEC
(C) urinary tract infection
(D) conjunctivitis
(E) meningitis
11. Does a positive FTA-ABS on the cord blood diagnose congenital syphilis?
(A) yes
(B) no
12. Would a negative RPR titer on the cord blood rule out congenital syphilis?
(A) yes
(B) no
13. In the case in the vignette, can you rule out the possibility that the mother has been reinfected with syphilis since her treatment 2 years ago?
(A) yes
(B) no
14. What would be the most conservative approach to the management of this newborn?
(A) follow the baby’s RPR titers over the next 6 months
(B) treat the baby with one intramuscular (IM) benzathine penicillin injection
(C) treat the baby with 10 days of IM aqueous procaine penicillin or IV aqueous penicillin
(D) follow the RPR over the next 12 months, but no treatment
(E) do a lumbar puncture (LP) to obtain cerebrospinal fluid (CSF) for analysis and serologic testing
15. If the mother had received adequate intrapartum penicillin prophylaxis for GBS, would that eliminate the concern over the possibility of congenital syphilis in the newborn?
(A) yes
(B) no
16. Of the following choices, what should be done with a term newborn whose mother did not receive intrapartum penicillin prophylaxis for her known group B streptococcal colonization?
(A) admit the infant to the NICU and observe
(B) draw a blood culture and leukocyte count and admit the infant to the well-baby nursery and observe
(C) begin the baby on oral penicillin
(D) begin the baby on ampicillin and gentamicin after a leukocyte count and a blood culture
(E) give the baby a 50 mg/kg IM of ceftriaxone, one time
17. If the blood culture is positive, how long will it likely take to be recognized as such by the microbiology laboratory staff?
(A) within 24-36 hours
(B) 48-72 hours
(C) more than 72 hours
(D) there is patient-to-patient variation
(E) this information is not known
18. If the baby develops symptomatic early-onset GBS disease, this will most likely present at
(A) less than 24 hours of age
(B) after 24-48 hours of age
19. How long should the baby in question 15 remain in the hospital for observation for GBS disease, assuming she or he is asymptomatic?
(A) 24 hours
(B) 48 hours
(C) 72 hours
(D) more than 72 hours
(E) no observation is needed if parents have available transportation and a working phone
ANSWERS
1. (E) A treponemal test, usually the FTA-ABS, remains reactive for life even after adequate therapy. Although any positive RPR or similar test must be confirmed to be syphilis by a test like the FTA-ABS. RPR and VDRL test are nontreponemal tests used to screen patients for syphilis. The nontreponemal tests have high sensitivity but relatively low specificity for the diagnosis of syphilis. They provide quantitative results that can be used to monitor response to therapy and define disease activity. Thus, a rise is the RPR or VDRL titer would suggest active syphilis. However, the RPR can be falsely negative in late congenital syphilis. A false-positive RPR can be associated with viral infections (eg, infectious mononucleosis, varicella, measles, and hepatitis) as well as lymphoma, tuberculosis, malaria, connective tissue disorders, and pregnancy itself.
2. (B) Neonatal RPR titers 4 times or more the mother’s titers are said to be indicative of congenital infection. Likewise, a fourfold or more decrease in a maternal RPR titer is indicative of successful treatment in the mother. Congenital syphilis can be divided into early and late stages. In the early stage, congenital syphilis symptoms may begin any time during the first 2 years of life, even if the neonate is asymptomatic at birth. Parenteral penicillin is the treatment of choice for congenital syphilis. The Jarisch-Herxheimer reaction (fever, chills, malaise, rash, hypotension, tachycardia after treatment of syphilis) is rare in the immediate newborn period.
3. (D) All are possible manifestations of congenital syphilis except PDA, which is commonly associated with congenital rubella syndrome. Myocarditis may be a manifestation of congenital syphilis.
4. (A) Gastroschisis (see Figure 115-1) in the neonate is associated with maternal cocaine use. Ebstein anomaly is associated with maternal use of lithium. LGA babies are commonly associated with diabetic and/or obese mothers. Neural tube defects are associated with the maternal use of anticonvulsants. One study has linked maternal use of metamizole, a nonsteroidal, anti-inflammatory drug banned in many parts of the world, to an increased risk of Wilms tumor in their children.
FIGURE 115-1.
5. (A) Neonatal abstinence syndrome (NAS) is classically associated with maternal opiate use during pregnancy but has been attributed to maternal use of other drugs, including ethanol, tobacco, and caffeine. Neonates affected by NAS tend to be very irritable with high-pitched crying, sweating, diarrhea, vomiting, poor feeding, and restlessness/hyperactivity. A standardized NAS scoring form is used to assess severity and to help determine a need for medical therapy. In the delivery room, if a mother is known to abuse opiates, naloxone is not indicated for the baby because abrupt drug withdrawal may provoke seizures. Supportive care such as a low-lit environment with minimal stimulation is important. The affected neonate will have an increased metabolism, so adequate intake with higher calorie formula or fortified breast milk is essential. Severe diarrhea may lead to skin irritation and breakdown in the diaper area, so frequent diaper changes and good topical barriers are key. If medical therapy is indicated for withdrawal symptoms, phenobarbital or an oral opiate may help.
6. (E) Infants born with fetal alcohol syndrome (FAS) and those with anticonvulsant embryopathy have similar, overlapping clinical features. FAS infants tend to be SGA and have microcephaly, whereas those with anticonvulsant embryopathy usually do not have either.
7. (C) Early-onset vitamin K–deficient hemorrhagic disease of the newborn is a well-documented complication of infants born to mothers who used anticonvulsants during pregnancy.
8. (C) Macrolides like erythromycin or lincosamides like clindamycin are indicated for intrapartum antibiotic prophylaxis against GBS if the mother has a history of anaphylaxis to penicillins. Whereas the penicillins are close to 100% effective in preventing early-onset GBS disease, there is up to 15% resistance among GBS strains with macrolides. Thus susceptibility testing in the prenatal period is essential when culturing for GBS if these alternative drugs are contemplated. If there is known resistance to the macrolides, vancomycin is the third-line prophylactic agent for IAP.
9. (B) Intrapartum prophylaxis is not intended to prophylaxis against late-onset disease. An increase in neonatal sepsis due to other causes than GBS has not been documented.
10. (E) Congenital GBS sepsis can be divided into early onset (in the first week of life) and late onset (day of life 8 to 3 months of age) infection. Early-onset infection tends to occur in the first day of life and can present with nonspecific signs such as poor feeding, temperature instability, nasal flaring, and lethargy. Late-onset infection, which may also present with nonspecific signs and symptoms, commonly presents with signs of meningitis that can, of course, be subtle in a young infant.
11. (B) A positive FTA-ABS test can occur secondary to passively acquired immune globulin (Ig)G antibody and may take 1 year or longer to become negative.
12. (B) Serologic tests such as RPR and VDRL may be falsely negative in very early congenital syphilis that had an infection onset within 4-6 weeks of term.
13. (B) The mother’s RPR, if she was adequately treated 2 years ago, should have become nonreactive by now. Her titer of 1:4 could represent new infection. There is no documented immunity to protect against reinfection.
14. (C) The baby should be treated for congenital syphilis. The mother’s titer of 1:4 at delivery might represent reinfection. Benzathine penicillin delivers inadequate levels of penicillin to reliably treat any possible CNS disease. There is no test available to exclude the possibility of CNS syphilis with certainty, although many mistakenly believe that a normal LP excludes neurosyphilis.
15. (B) If a mother is treated for syphilis less than 1 month before delivery with any antibiotic regimen, her baby should be evaluated and treated for congenital syphilis, irrespective of GBS intrapartum prophylaxis.
16. (B) Although intrapartum penicillin was not administered, the risk for GBS infection is still low. Observation after a minimal investigative evaluation is acceptable.
17. (A) Modern technology in use in clinical microbiology laboratories monitors blood culture bottles continuously for CO2 production. A blood culture specimen in which bacteria are growing may turn positive at any time. However, most cultures “turn positive” very quickly and yield positive results in 1-2 days.
18. (A) Despite intrapartum antimicrobial prophylaxis, which has greatly decreased the occurrence of early onset (<7 days) GBS disease, most cases are still recognized on the first day of life.
19. (B) Even though the mother was known to be a carrier, the risk of GBS disease is still relatively low in a term baby, and most cases are recognized on the first day of life. Along with the fact that the U.S. health system does not generally support prolonged observation of asymptomatic term babies, 48 hours of observation is believed by most experts to be sufficient.
SUGGESTED READING
American Academy of Pediatrics. Syphilis. In: Pickering LK, Baker CJ, Kimberlin DW, Long SS, eds. Red Book 2009 Report of the Committee on Infectious Diseases. 28th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2009.
Behrman RE, Kliegman RM, Jenson HB. Syphilis. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, PA: WB Saunders; 2007.
Chakraborty R, Luck S. Managing congenital syphilis again? The more things change . . . Curr Opin Infect Dis. 2007;20(3):247-252.
Gotoff SP. Group B Streptococcal infections. Pediatr Rev. 2002;23(11):381-386.
Maisels MJ. Neonatal jaundice. Pediatr Rev. 2006;27(12):443-453.
Screening for syphilis infection in pregnancy: U.S. Preventive Services Task Force reaffirmation recommendation statement. Ann Intern Med. 2009;150(10):705-709.
CASE 116: A NEONATE WITH HYPERPIGMENTED MACULAR SKIN FINDINGS
A full-term 2620-g infant is born to a 28-year-old G2P2 mother who had regular prenatal care. You were asked to attend the delivery because of meconium-stained amniotic fluid. The baby is born in good condition with Apgar scores of 9 and 9. No special interventions are required. As you examine the baby, you notice six discrete, round, 0.5-cm, hyperpigmented macular lesions on the abdomen, back, and left calf. The parents are not related to each other, and both deny any similar lesions in family members on either side.
SELECT THE ONE BEST ANSWER
1. What is the most accurate statement about these lesions?
(A) “the baby is abnormal, I’m not sure”
(B) “we need a dermatology consult”
(C) “these lesions will most likely fade with time”
(D) “the baby needs to be transferred to the intensive care unit for observation and further workup”
(E) “these skin lesions are not specific to any particular disease”
2. Café au lait macules (CALMs) are most prevalent in which racial/ethnic group?
(A) Asian
(B) African American
(C) White
(D) Hispanic
(E) Native American
3. You suspect neurofibromatosis (NF)-1. Which physical finding would you expect to see in the newborn period to help make the diagnosis?
(A) plexiform neurofibromas
(B) abdominal mass
(C) bilateral cryptorchidism
(D) Crowe sign
(E) cataracts
4. Juvenile xanthogranulomas in patients with NF-1 are associated with an increased risk for developing
(A) chronic myeloid leukemia
(B) vestibular schwannomas
(C) Wilms tumor
(D) coronary artery disease
(E) fulminant hepatic failure
5. You recall examining another young girl with similar skin lesions. You recently saw her in your clinic for a 3-year-old routine health maintenance visit. At that time the mother complained of axillary hair in her daughter. You notice, on examination, Tanner III pubarche and an 8- × 8-cm hyperpigmented macule with a very jagged border on her chest. Which study would help you make the diagnosis?
(A) magnetic resonance imaging (MRI) of the brain
(B) skeletal x-rays
(C) computed tomography (CT) of the abdomen
(D) karyotyping
(E) skin biopsy of the hyperpigmented macule
6. Hemangiomas are another common dermatologic finding in newborns. The least accurate statement about hemangiomas of infancy is
(A) hemangiomas in the midline spinal region may be associated with neural tube defects
(B) hemangiomas have an increased risk for malignant transformation
(C) hemangiomas can rarely cause consumptive coagulopathy
(D) multiple cutaneous hemangiomas may be associated with internal hemangiomas
(E) they are vascular tumors
7. You are asked to evaluate a 2-day-old girl in the NICU who has a large facial hemangioma. On examination, you note absent femoral pulses and abnormal red reflexes in both eyes. Which of the following is also associated with these clinical findings?
(A) supernumerary digits
(B) sternal clefting
(C) clitoromegaly
(D) torticollis
(E) developmental dysplasia of the hips
8. Infants with eyelid hemangiomas are most at risk for
(A) seizure disorders
(B) vision problems
(C) learning disabilities
(D) ipsilateral intracranial calcifications
(E) neural tube defects
ANSWERS
1. (E) These hyperpigmented macules most likely are CALMs, which tend to be uniformly hyperpigmented discrete macules that get larger during childhood. They are not specific for any particular syndrome and often are incidental findings with no medical significance. However, the greater the number of CALMs, the more likely there will be an associated physical finding. Histologically, these macules have giant melanosomes in the melanocytes and basal keratinocytes.
2. (B) The frequency of CALMs is 0.1% in Jewish, 0.3% in white, 0.4% in Chinese, 0.5% in Arab, 3% in Hispanic, and 18% in African American newborns.
3. (D) In newborns with NF-1, CALMs and the Crowe sign are the first manifestations. Neurofibromas tend to appear later in childhood. To make the diagnosis of NF-1, at least two of these seven criteria must be met:
1. CALMs →>6 in number AND >5 mm in diameter in prepubertal patients or >15 mm in postpubertal patients
2. Axillary or inguinal freckling (Crowe sign)
3. Neurofibromas
4. Lisch nodules (pigmented hamartomatous nevi)
5. Optic nerve glioma
6. Osseous lesion
7. First-degree relative with NF-1
A plexiform neurofibroma (2 or more neurofibromas networked together) is pathognomonic for NF-1, whereas a solitary/single neurofibroma is not. Typical osseous lesions include sphenoid bone dysplasia or dysplasia of the long bone cortex. There is a high (up to 50%) rate of developing NF-1 without any familial or genetic predisposition.
4. (A) Vestibular schwannomas are associated with NF-2. Wilms tumor is found in aniridia, genitourinary anomalies, and mental retardation (WAGR syndrome) and Beckwith-Wiedemann syndrome. Juvenile chronic myelogenous leukemia is primarily referred to as juvenile myelomonocytic leukemia.
5. (B) The macule described is a so-called coast of Maine CALM that is commonly seen in McCune-Albright syndrome. Typical CALMs are described as having a “coast of California” appearance. McCune-Albright syndrome has three findings: coast of Maine CALM, endocrine hyperfunction (typically manifested as precocious puberty), and polyostotic fibrous dysplasia, which can be seen on skeletal radiographs.
6. (B) Hemangiomas are the most common vascular tumor in the newborn period. They are benign vascular tumors that tend to have a vigorous proliferative phase in the first year of life followed by a slow involution period throughout childhood. There is no risk of malignant transformation, unlike that posed by a congenital melanocytic nevi, but hemangiomas may cause functional compromise or cosmetic disfigurement depending on their size and location. Hemangiomas in the diaper area may ulcerate, become painful, and/or may become infected. Visible hemangiomas in the “beard distribution” are associated with subglottic hemangiomas, which may lead to respiratory compromise as they enlarge. visible hemangiomas in the midline back may have associated neural tube defects. Kasabach-Merritt syndrome is associated with large hemangiomas that cause trapping of platelets that may lead to consumptive coagulopathy. Multiple hemangiomas may suggest the presence of visceral hemangiomas (neonatal hemangiomatosis).
7. (B) The patient described most likely has PHACE(S) syndrome, which has a female predominance. This acronym refers to the following constellation of findings:
Posterior fossa malformations
Hemangiomas
Arterial anomalies
Coarctation of the aorta and other cardiac
malformations
Eye abnormalities
Sternal clefting
8. (B) Periorbital hemangiomas may directly compress the eye causing astigmatism and visual impairment. If the periorbital finding was a port wine stain (vascular malformation) instead of a hemangioma (vascular tumor), you might consider Sturge-Weber syndrome as a possibility. Sturge-Weber syndrome is a neurocutaneous syndrome consisting of a port wine stain involving the ophthalmic branch of the trigeminal nerve, leptomeningeal involvement, and ipsilateral eye abnormalities (cataracts, glaucoma, buphthalmoses, etc). Learning disabilities and seizures are common in Sturge-Weber syndrome. Hemangiomas in the midline of the back are associated with neural tube defects.
SUGGESTED READING
Hernandez JA, Morelli JG. Birthmark of potential medical significance. NeoReviews. 2003;4:c263-c268.
Raygada M, Arthur DC, Wayne AS, Rennert OM, Toretsky JA, Stratakis CA. Juvenile xanthogranuloma in a child with previously unsuspected neurofibromatosis type 1 and juvenile myelomonocytic leukemia. Pediatr Blood Cancer. 2010;54(1): 173-175.
Tekin M, Bodurtha JN, Riccardi VM. Cafe au lait spots: the pediatrician’s perspective. Pediatr Rev. 2001;22;82-89.
Zvulunov A, Barak Y, Metzker A. Juvenile xanthogranuloma, neurofibromatosis, and juvenile chronic myelogenous leukemia. World statistical analysis. Arch Dermatol. 1995;131(8):904-908.
CASE 117: A TERM NEONATE NEEDS AN INITIAL EXAMINATION
A healthy term African American baby girl is born vaginally without instrumentation after a 12-hour labor. You examine her at 2 hours of life.
SELECT THE ONE BEST ANSWER
1. You note that her head is “cone shaped,” and there is an ecchymosis and swelling of the scalp at the vertex. When you apply pressure with your finger, an imprint is left. This condition is most likely a
(A) cephalhematoma
(B) subgaleal hematoma
(C) caput succedaneum
(D) A or B
(E) none of the above
2. The following day, you note a swelling over the right parietal area of the scalp that feels fluctuant. This is most likely a
(A) cephalhematoma
(B) subgaleal hematoma
(C) caput succedaneum
(D) A or B
(E) none of the above
3. Later on, the mother calls the nurse because the baby has developed a rash. It is red, macular, and papular/pustular and most prominent over the face and trunk. The mother wonders if the baby is allergic to her milk. You explain
(A) “this is erythema toxicum”
(B) “we need to change the baby to a soy formula”
(C) “the baby is allergic to the baby lotion”
(D) “this is a staphylococcal infection”
(E) “I must perform some laboratory tests to determine the cause”
4. In the above case you decide to do a Wright stain of material from a pustule. You will likely see
(A) sheets of eosinophils
(B) many bacteria
(C) many neutrophils
(D) a dendritic pattern
(E) cellular debris
5. If there had been shoulder dystocia at delivery and the baby was holding one arm limply at her side, but had a good palmar grasp on the same side, you would diagnose a probable
(A) upper brachial plexus injury (Erb palsy)
(B) lower brachial plexus injury (Klumpke palsy)
(C) fractured clavicle
(D) Werdnig-Hoffman syndrome
(E) fractured humerus
6. Within the gluteal fold, at the tip of the coccyx, you find a deep dimple. You should
(A) obtain an ultrasound of the spine
(B) obtain an MRI of the spine
(C) order a neurosurgical consult
(D) do nothing
(E) obtain a renal ultrasound
7. At the anterior margin of the crus of the helix, you note a pinhole opening. The least accurate statement about ear pits is
(A) they commonly run in families
(B) they are an indication for a renal ultrasound
(C) it is important to assess hearing in both ears
(D) they may be associated with branchial cleft fistulae along the neck
(E) they may be associated with Goldenhar syndrome
8. You find a minor anomaly on your examination of the baby, namely, bilateral single palmer creases. Should you suspect Down syndrome?
(A) yes
(B) no
9. The mother asks about the red spots on the white of the baby’s eyes. You explain that
(A) they are small hemorrhages from the pressure of labor on the baby
(B) they may represent brain injury and you will order tests
(C) they are from the ointment put in the eyes
(D) you suspect chlamydia
(E) you suspect gonorrhea
10. The mother expresses concern about a white vaginal discharge. You explain to the mother
(A) this is normal
(B) you will do tests for an infection on the baby
(C) you will obtain an estradiol level on the baby
(D) you will obtain a luteinizing hormone (LH) and follicle-stimulating hormone (FSH) level on the baby
(E) you will need to obtain lab work on the mother
11. There are multiple tiny yellow papules on the baby’s nose. These are
(A) prominent sebaceous glands
(B) epithelial inclusion cysts (milia)
(C) neonatal acne
(D) dermoid cysts
(E) scabies
12. You feel a sharp liver edge 2-3 cm below the right costal margin. This represents hepatomegaly
(A) yes
(B) no
13. On examination of the hips, you find instability on one side with a palpable “clunk” on the Ortolani maneuver. You should
(A) immediately put the baby in a harness
(B) order triple diapers for the baby
(C) repeat the examination (if the clicks are still apparent, an ultrasound examination is the next step)
(D) order an MRI
(E) order a technetium triple-phase bone scan
14. During your discharge examination on day 2, you hear a grade 2-3 systolic murmur. You tell the parents that
(A) “it is nothing; all babies have murmurs”
(B) “I am going to check an oxygen saturation”
(C) “I am going to order an electrocardiogram (ECG)”
(D) “I am going to call a pediatric cardiologist”
(E) “I am going to transfer your infant to the NICU for further evaluation”
ANSWERS
1. (C) Caput succedaneum is a diffuse, sometimes ecchymotic soft tissue swelling of the presenting part in a vertex delivery.
2. (A) Cephalhematoma is a subperiosteal hemorrhage. Therefore, it does not cross suture lines but can be bilateral. There is no discoloration of the overlying scalp. Subgaleal hemorrhage occurs as a consequence of subaponeurotic bleeding. It crosses suture lines and is not usually associated with a skull fracture. Because a subgaleal hemorrhage can be large, it can lead to a drop in the hematocrit and resulting hyperbilirubinemia.
3. (A) A maculopapular rash on an erythematous base seen 1-3 days after birth is most likely erythema toxicum. It has no known allergic component and requires no laboratory investigation.
4. (A) A Wright stain of material from pustules will show eosinophils. Bacteria and neutrophils should be absent.
5. (A) Forty-five percent of brachial plexus injuries are associated with shoulder dystocia. Erb palsy is an upper brachial plexus injury involving the 5th and 6th cervical nerves. The arm is adducted and pronated. In Erb palsy, the hand grasp is present. In Klumpke palsy, the 7th and 8th cervical and 1st thoracic nerves are affected and the hand grasp is absent.
6. (D) Most dimples that fall within the gluteal fold are normal. Dimples that are large and located above the gluteal fold, such as a sacral dimple, are associated with other midline skin lesions like hemangiomas, lipomas, or skin tags and should be further investigated.
7. (B) Preauricular pits may be hereditary and can be commonly found in other family members. Preauricular pits, as a finding in certain syndromes, have been associated with deafness. There is no known association between preauricular pits and renal disease.
8. (B) A single palmar crease is a nonspecific finding in an otherwise normal infant. A unilateral single palmar crease is present in 4% of normal people, and bilateral, single palmer creases occur in about 1% of normal people. Down syndrome nearly always has other associated findings.
9. (A) Small subconjunctival hemorrhages are common and are of no clinical importance. No further workup is necessary.
10. (A) This is a result of maternal estrogen that crossed the placenta and will resolve with time. It takes longer for a baby girl to metabolize and excrete the estrogen. Thus sometimes maternal estrogen can cause some vaginal discharge in the baby.
11. (B) Milia are tiny inclusion cysts within the epidermis. Sebaceous hyperplasia occurs in large plaques.
12. (B) The liver is usually palpable 2-3 cm below the costal margin in normal neonates without associated disease.
13. (C) The diagnosis is most likely laxity of the ligaments, a benign disorder, but investigation for hip dislocation should occur if the finding is consistently present.
14. (D) Any murmur grade 2 or greater after the first 24 hours of life warrants a cardiologist’s evaluation to check for the presence of an atrial septal defect, a ventricular septal defect and to evaluate the baby’s hematologic status. If the murmur is greater than grade 2, a follow-up examination suffices as an initial approach because this is most likely a flow or benign murmur.
SUGGESTED READING
Martin R, Fanaroff AA, Walsh M. Fanaroff and Martin’s Neonatal-Perinatal Medicine Diseases of the Fetus and Infant. 8th ed. Chicago, IL: Elsevier Mosby; 2006.
CASE 118: A TERM NEONATE FOUND TO HAVE LOW BIRTHWEIGHT AFTER DELIVERY
A full-term baby is born to a 16-year-old mother. The prenatal course was notable for suspected intrauterine growth retardation. The birthweight is 2325 g.
SELECT THE ONE BEST ANSWER
1. In the evaluation of a low-birthweight term SGA newborn, which of the following should be considered?
(A) maternal vascular disease
(B) fetal chromosomal disorder
(C) in utero infection
(D) maternal fibroids
(E) all of the above
2. The presence of 1 major anomaly and how many minor anomalies would suggest the possibility of a major chromosomal defect?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
3. This SGA baby born to a teenage mother has some petechiae on the face and trunk. You do the following
(A) send evaluative tests for CMV
(B) send a serologic evaluation for toxoplasmosis
(C) send a blood culture to detect possible occult bacteremia
(D) A, B, and C
(E) none of the above
4. All are risk factors for congenital toxoplasmosis except
(A) eating steak tartare
(B) having a cat who lives indoors
(C) gardening
(D) exposure of a pregnant woman to an infant with toxoplasmosis
(E) all of the above
5. The differential diagnosis of a newborn who is SGA with a normal physical examination includes
(A) CMV
(B) rubella
(C) toxoplasmosis
(D) varicella
(E) A and C
6. Neonatal herpes skin lesions are most likely to be seen on day
(A) 1
(B) 3
(C) 5
(D) 8
(E) 21
7. What percentage of women with neonates who develop herpes simplex virus (HSV) are asymptomatic or have no history of having had herpes?
(A) less than 1%
(B) 1-5%
(C) 5-20%
(D) 60-80%
(E) more than 95%
8. Congenital toxoplasmosis has a prevalence in the United States of about
(A) 1:100
(B) 1:1000
(C) 1:10,000
(D) 1:100,000
(E) 1:1,000,000
9. With regard to treatment of congenital toxoplasmosis, all of the following statements are true except
(A) prenatal treatment decreases transmission rate
(B) prenatal treatment of an infected fetus decreases fetal and newborn clinical manifestations
(C) postnatal treatment for 1 year is needed for infected symptomatic children
(D) postnatal treatment for 1 month is needed for infected asymptomatic children
(E) all of the above
10. A baby diagnosed with congenital CMV infection passes the hearing screening test. Which of the following statements are true?
(A) the baby is fortunate; there will be no hearing loss
(B) the baby is still at risk for progressive hearing loss and will require repeat testing in the future
(C) the baby needs to see an audiologist for more advanced testing
(D) the auditory brainstem response (ABR) must have been done incorrectly
(E) none of the statements are true
11. An SGA term baby is at risk for
(A) hypoglycemia
(B) polycythemia
(C) hypothermia
(D) A, B, and C
(E) none of above
12. SGA neonates should have glucose levels followed for up to how long after birth?
(A) 2 hours
(B) 12 hours
(C) 24 hours
(D) 3 days
(E) 1 week
13. In SGA infants, the most important predictor of future growth and development is
(A) weight at birth
(B) head size at birth
(C) length at birth
(D) body mass index (BMI)
(E) body surface area (BSA)
ANSWERS
1. (E) The causes of intrauterine growth retardation can be divided into three main categories:
• Systemic disease or causes in the mother that affect uteroplacental function. Examples include chronic hypertension, severe diabetes, lupus, and preeclampsia.
• Fetal causes (ie, those that inhibit the growth potential of the fetus). Examples include chromosomal disorders like trisomy 18 or congenital infections.
• Local uterine causes such as large fibroids, bicornuate uterus, or multiple uterine occupants, eg twins, that impair the growth of the fetus secondary to space constraints.
2. (B) An infant that has 2 minor anomalies and 1 or more major anomaly is likely to have an underlying genetic diagnosis.
3. (E) Petechiae on the face, trunk, and in the groin area can occur in normal infants. The platelet count should be checked. If the platelet count and the rest of the examination is normal, there is no need to perform additional evaluations. However, if there are petechiae on an SGA baby who also has hepatosplenomegaly, this infant should be evaluated further for intrauterine infections such as CMV or rubella. In this instance, there should be associated thrombocytopenia.
4. (D) Toxoplasma gondii is a protozoan that is acquired through ingestion of undercooked or raw meat containing the tissue cyst stage of the parasite or exposure to other food materials that are contaminated by oocysts excreted in the feces of infected cats. There is no person-to-person transmission.
5. (E) Ninety percent of newborns congenitally infected with CMV are asymptomatic at delivery, and 10% will have signs and symptoms. Affected infants may be SGA. They may also have microcephaly, intracranial calcifications, hepatosplenomegaly, petechiae, thrombocytopenia, or hearing loss. In this baby, the examination is normal, although the baby is SGA. The diagnosis of congenital CMV can be made by PCR of blood or viral culture of urine obtained within the first 3 weeks of life. Infants with congenital toxoplasmosis are asymptomatic in 70-90% of cases.
6. (D) The incidence of neonatal HSV infection is approximately 1:3000 to 1:7000 live births. HSV infection may occur transplacentally, intrapartum, or postpartum. Most infected neonates acquire the virus at delivery. Only 30-50% of babies present with skin lesions that commonly appear around 7-10 days but can appear at any time.
7. (D) About 60-80% of women with neonates who develop HSV are asymptomatic or have no history of ever having herpes.
8. (C)
9. (D) Treatment of the mother during pregnancy decreases the transmission rate to the fetus. If the mother and fetus are both infected, treatment of the mother with pyrimethamine and sulfadiazine decreases fetal clinical manifestations. Symptomatic or asymptomatic infected babies should be treated with pyrimethamine and sulfadiazine for 1 year.
10. (B) Ninety percent of babies with congenital CMV are asymptomatic at birth. Sensorineural hearing loss is the most common late sequela.
11. (D) SGA babies are at risk for hypoglycemia secondary to decreased glycogen stores, decreased gluconeogenesis, and increased sensitivity to insulin. They are at risk for hypothermia secondary to decreased subcutaneous fat and a large surface area to body weight ratio. They are at risk for polycythemia secondary to chronic hypoxia.
12. (D) Blood sugar should be monitored in an SGA baby for up to 3 days. Glycogen stores generally take 2-3 days to develop.
13. (B)
SUGGESTED READING
Martin R, Fanaroff AA, Walsh M. Fanaroff and Martin’s Neonatal-Perinatal Medicine Diseases of the Fetus and Infant. 8th ed. Chicago, IL: Elsevier Mosby; 2006.
CASE 119: A 36-WEEK-GESTATION NEONATE’S MOTHER WANTS AN EARLY DISCHARGE
A 2300-g birthweight, 36-week gestation baby is now 40 hours old. The mother is all set to take him home.
SELECT THE ONE BEST ANSWER
1. The American Academy of Pediatrics (AAP) guidelines for consideration of early discharge (<48 hours) of the healthy neonate specify that the baby must be at least how many weeks’ gestation?
(A) 34
(B) 36
(C) 38
(D) 40
(E) gestational age is not a consideration
2. The guidelines for an early discharge also specify that the newborn must have a birthweight of
(A) at least 1800 g
(B) at least 2000 g
(C) at least 2500 g
(D) at least 3000 g
(E) a birthweight 1800 g or more and appropriate for gestational age (AGA)
3. All of the following information would be needed for assessment of discharge readiness for this baby except
(A) a serum bilirubin either normal or unlikely to be on a trajectory requiring phototherapy
(B) feeding ability
(C) follow-up care arrangements in place
(D) demonstrated hemostasis after circumcision
(E) all of the above would be needed information
4. What would be considered the most reliable information for establishing the gestational age in this small baby?
(A) Ballard score
(B) prenatal ultrasound before 18 weeks’ gestation
(C) calculation based on last menstrual period
(D) bone age, left wrist
(E) bone age, left foot
5. After your assessment of risk in sending this baby home at 40 hours, what would be the most appropriate thing to tell the parents?
(A) they should watch for jaundice and call with any concerns
(B) they should observe his weight
(C) you are concerned enough not to send the baby home
(D) they should follow up in 3 days or less with the pediatrician
(E) they should watch for jaundice, keep the child in front of a sunny window, and call with any concerns
6. The parents of a term normal birthweight girl ask to be discharged at 12 hours. The mother is an experienced breast feeder and feedings are going fairly well. The baby has not passed any stool. You tell them
(A) your admission examination is normal so the baby can go home
(B) you want the baby to have passed meconium before you write an order for discharge
(C) the baby has no jaundice and therefore can go home
(D) the child cannot be discharged before 36 hours of age
(E) if the discharge examination is normal, she can go home
7. For a baby to be discharged, it is important that
(A) the baby has completed at least two successful feedings
(B) the baby has coordinated suck and swallow
(C) during breastfeeding the baby latches to the breast without pain to the mother
(D) the baby has urinated and passed at least one stool
(E) all of the above
8. All infants having a short hospital stay must be examined by experienced health personnel within
(A) 24 hours of discharge
(B) 48 hours of discharge
(C) 72 hours of discharge
(D) within a week of discharge
(E) within the first 2 weeks of life
9. Ductal-dependent cardiac lesions may not be apparent until
(A) 2 hours of life
(B) 6 hours of life
(C) 12 hours of life
(D) 24 hours of life
(E) more than 24 hours of life
10. Contraindications to early discharge are
(A) low birthweight
(B) congenital anomalies
(C) prematurity
(D) teenage mother
(E) all of the above
11. Before early discharge, cord blood type and a Coombs test should be performed on
(A) all babies
(B) babies whose mothers are group O
(C) all babies with a family history of jaundice
(D) babies whose mothers are Rh negative
(E) B and D
ANSWERS
1. (C) Premature babies younger than 38 weeks of gestation can have feeding problems and temperature instability. They should be observed for more than 48 hours to establish oral feedings, monitor bilirubin, and monitor temperature stability in an open crib.
2. (E) Babies that are SGA and babies lighter than 1800 g have problems maintaining their temperature in an open crib.
3. (E) Babies at discharge should be feeding well, have a serum bilirubin level in the low-risk zone of the Bhutani nomogram, should have achieved bleeding hemostasis postcircumcision, and have a follow-up appointment.
4. (B) The most accurate assessment of gestational age uses the first trimester ultrasound measurement of crown-rump length.
5. (C)
6. (B) Ninety percent of newborn babies pass meconium in the first 24 hours of life. Babies should be observed long enough to make sure feedings are established, the baby has passed urine and stool, and the bilirubin is in the range of the Bhutani nomogram low-risk zone.
7. (E)
8. (B) The AAP recommends a follow-up visit within 48 hours after early discharge.
9. (E)
10. (E) Low-birthweight babies, premature babies, and babies with congenital abnormalities may have feeding problems, temperature instability, hyperbilirubinemia, or metabolic problems like hypoglycemia or hypocalcemia. They should not be discharged early. Teenage mothers should be evaluated by a social worker to make sure there is an adequate support system at home.
11. (E) Babies born to O-positive mothers or Rhnegative mothers have the possibility of blood group incompatibility if the baby’s blood group is A, B, or the baby is Rh positive. Therefore, cord blood type determination and a direct Coombs test should be done in mothers with blood group O or Rh negative.
SUGGESTED READING
American Academy of Pediatrics. Committee on fetus and newborn. Hospital stay for healthy term newborns. Pediatrics. 1995;96:788-790.
American Academy of Pediatrics: Subcommittee on Hyperbilirubinemia. Management of hyperbilirubinemia in the newborn infant 35 or more weeks of gestation. Pediatrics. 2003;114:297-316
CASE 120: A TERM NEONATE REQUIRES ROUTINE CARE IN THE NURSERY
A full-term 3500-g baby girl is born after a normal vaginal delivery following 4 hours of labor with rupture of membranes. The mother brought the baby for all of the scheduled prenatal visits and had no complications. The family history is noncontributory.
On examination the baby has normal vital signs and is pink and vigorous.
SELECT THE ONE BEST ANSWER
1. Which routine procedures should be done in the birth room?
(A) administer hepatitis B vaccine
(B) administer vitamin K IM
(C) administer vitamin K orally
(D) apply prophylactic ophthalmic antibiotic ointment
(E) B and D
2. Upon admission to the nursery, what other routine procedures should be done?
(A) glucose screen
(B) hematocrit screen
(C) glucose water feeding
(D) A, B, and C
(E) none of the above
3. If the mother’s lower vaginal and rectal culture results for GBS were unknown, what would you do for the baby if no prophylactic penicillin had been given to the mother intrapartum?
(A) start oral amoxicillin
(B) draw a blood culture, a CBC, and start IV penicillin
(C) do an LP
(D) observe without intervention
(E) draw a blood culture and a CBC but do not start antibiotics
4. If the mother is GBS positive and received prophylactic intrapartum penicillin for more than 4 hours before delivery, what would be your best course?
(A) obtain a blood culture and observe
(B) obtain a CBC
(C) A and B
(D) administer IM antibiotics
(E) none of the above
5. If a mother has a positive cervical culture for gonococcus (N gonorrhoeae) and was not treated before delivery, what would you do?
(A) culture the baby’s conjunctivae and wait for the results
(B) obtain a blood culture
(C) observe for illness before intervening
(D) give IM ceftriaxone 50 mg/kg, one time
(E) B and D
6. If a mother has untreated Chlamydia at the time of delivery, what would you do?
(A) give a double dose of erythromycin ophthalmic ointment
(B) do a nasopharyngeal culture and wait for results
(C) start oral erythromycin
(D) monitor for signs and symptoms of infection
(E) A and B
7. At the end of the first day of life, you see that no urine output has been recorded by the nurse for an otherwise well newborn with a normal examination. Your best course of action should be
(A) catheterize the bladder
(B) give 4 ounces of glucose water
(C) order a renal ultrasound
(D) do nothing but continue to observe
(E) give a 20 mL/kg bolus of IV fluids
8. An 18-hour-old breastfeeding newborn spits yellow material after a feed. You should
(A) order an upper GI series
(B) observe
(C) order a lower GI series
(D) order a flat plate of the abdomen
(E) hold all feeds
9. A 40-hour old formula-fed newborn has had no stools recorded in the nurses’ notes. The best course of action includes
(A) asking the mother if the baby has passed any stools
(B) ordering a glycerin suppository
(C) performing a rectal examination
(D) B and C
(E) ordering a suction rectal biopsy
10. The mother of a 10-hour-old newborn wants the formula changed to soy because the baby has vomited the regular formula after taking 40 mL. The best course of action includes
(A) agreeing that the baby cannot tolerate the cow’s milk based formula
(B) taking a family history for lactose intolerance
(C) suggesting that the baby may have been overfed
(D) suggesting that a more elemental formula be used
(E) suggesting that a nurse perform the next feed for observational purposes
11. The parents of a breast-fed baby girl tell you on day 2 that the baby is voiding blood. The best course of action includes
(A) order prothrombin time (PT) and partial thromboplastin time (PTT) determinations immediately
(B) explain to the parents that this is vaginal withdrawal bleeding and is normal
(C) order a renal ultrasound to look for renal vein thrombosis or tumor
(D) consult hematology/oncology
(E) consult urology
12. The mother of a full-term 12-hour-old breast-fed baby is worried that the baby is sleepy and has had only one successful feeding. There is no history of diabetes in the mother. The mother’s rectovaginal culture obtained at 36 weeks’ gestation grew no GBS, and there was neither prolonged rupture of membranes before delivery nor signs of chorioamnionitis at time of delivery. The next best step you should do is
(A) order a glucose screen
(B) order the nurse to feed formula
(C) ask the mother to put the baby skin to skin with her
(D) order a glucose water feeding
(E) turn the heat up in the mother’s room
13. On the admission for physical examination in the nursery, you note a grade 2/6 ejection systolic murmur at the upper left sternal border of an otherwise healthy newborn. The best course of action includes
(A) tell the parents that the baby might have congenital heart disease
(B) request a cardiac consult
(C) observe
(D) transfer to the NICU
(E) obtain a blood gas
14. On physical examination at 50 hours, you find a grade 3/6 systolic murmur at the lower left sternal border. The best course of action includes
(A) discharge the baby with instructions to follow up with a pediatrician in 48 hours
(B) tell the parents the baby might have congenital heart disease
(C) request a cardiac consult
(D) order an ECG and measure the oxygen saturation
(E) C and D
15. At the time of discharge of a 2-day-old term baby, you tell the parents to
(A) make an appointment with their pediatrician for a 2-week visit
(B) see how things go and call the pediatrician as needed
(C) book a pediatric visit before leaving the hospital for 1-2 days after discharge
(D) book a pediatric visit before leaving the hospital for 3-4 days after discharge
(E) A and B
ANSWERS
1. (E) In most hospitals, IM vitamin K and prophylaxis for conjunctivitis are administered in the birth room. Vitamin K is not absorbed after oral administration. The hepatitis B vaccine series is ideally initiated at birth but seldom in the delivery room.
2. (E) A term AGA baby is not at high risk for hypoglycemia. Babies at risk for hypoglycemia include those who are SGA, LGA, infants of diabetic moms, and premature babies. A routine hematocrit is not needed. The hematocrit should be done if the baby looks pale or ruddy.
3. (D) Because the baby was born at term and there are no other risk factors such as prolonged rupture of membranes more than 18 hours, maternal fever, history of a sibling with early-onset GBS disease, or urine culture positive for GBS during this pregnancy, no further workup or treatment is indicated.
4. (E) The baby is of term gestation; there are no other risk factors except mother’s colonization, and she has received adequate intrapartum antibiotic treatment.
5. (E) One dose of IM ceftriaxone should be given to babies born to mothers with untreated gonococcal infection. A conjunctival and blood culture should be done before treatment.
6. (D) Until recently, the AAP recommended that babies born to mothers with untreated Chlamydia infection should be treated with erythromycin for 14 days. Because the efficacy of prophylactic treatment is not known and there are reports linking erythromycin use in neonates to hypertrophic pyloric stenosis, the AAP now recommends that only infected infants should be treated. So nothing should be done at birth.
7. (D) If the baby has been feeding well, looks well, appears to be well hydrated, and the examination is normal, chances are that the baby had passed urine but it was not recorded.
8. (B) A small amount of spitting is common and most likely normal. The color of the vomitus is important. If there is any history of the baby vomiting bile or blood, further investigation should be done. In this patient who is being breast-fed, the yellow spitup is more than likely breast milk itself if the abdominal examination is normal. So no workup is indicated at this time.
9. (A) Most newborn babies (98%) pass meconium in the first 24 hours of life. Delayed meconium passage beyond 48 hours in an otherwise healthy full-term infant suggests Hirschsprung disease. Begin the evaluation by asking the mother to confirm the history.
10. (C) Generally a 10-hour-old baby will take anywhere from 15 to 30 mL per feeding.
11. (B) Pseudomenses or withdrawal bleeding can occur in normal newborn baby girls in the first few days of life.
12. (C) Because there is no history of diabetes in the mother and the neonate is full term, problems with hypoglycemia are less likely. Administration of glucose water is no longer an accepted practice and does nothing to help encourage breastfeeding in the neonate. Formula usually is not offered to healthy breastfeeding neonates and may actually interfere with successful breastfeeding in neonates. Turning up the heat in the room does not help arouse the neonate and may actually make the neonate sleepier.
13. (C) A grade II/VI murmur on the first day of life is most likely secondary to transition from in utero to extrauterine life and is a result of a PDA, or, alternatively, a sign of tricuspid regurgitation. An ECG, a chest radiograph, and an echocardiogram would be useful first steps.
14. (C) A murmur grade III/VI or louder on day 3 needs to be evaluated by a cardiologist. A chest x-ray, EKG, and echocardiogram will likely be necessary.
15. (C) The AAP recommends that babies discharged early be seen by a physician within 2 days of going home to assess bilirubin problems or feeding issues.
SUGGESTED READING
Martin R, Fanaroff AA, Walsh M. Fanaroff and Martin’s Neonatal-Perinatal Medicine Diseases of the Fetus and Infant. 8th ed. Chicago, IL: Elsevier Mosby; 2006.
Puig G, Sguassero Y. Early skin-to-skin contact for mothers and their healthy newborn infants: RHL commentary (last revised November 9, 2007). The WHO Reproductive Health Library. Geneva, Switzerland: World Health Organization.