Tintinalli's Emergency Medicine - Just the Facts, 3ed.

63. EMERGENCIES DURING THE SECOND HALF OF PREGNANCY

Howard Roemer

For essentially all conditions below, initiate immediate continuous fetal monitoring for a viable fetus.

VAGINAL BLEEDING

images Abruptio placentae, placenta previa, and preterm labor are the most common causes.

images Speculum and digital pelvic examination is contrain-dicated until ultrasound has been obtained to rule out placenta previa.

images Manage hemodynamic instability with lateral decubitos positioning, IV normal saline (NS), and/or packed RBCs.

images Obtain emergent obstetric consultation, CBC, type-and crossmatching leukoreduced packed cells, disseminated intravascular coagulation (DIC) profile, and electrolyte studies. Administer Rh (D) immu-noglobulin 300 micrograms to all Rh-negative patients.

ABRUPTIO PLACENTAE

images Abruptio placentae is the premature separation of the placenta from the uterine wall.

images Risk factors include hypertension, advanced maternal age, multiparity, smoking, cocaine use, previous abruption, and abdominal trauma.

images Clinical features include abdominal pain, vaginal bleeding (may be absent), uterine tenderness, or fetal distress; DIC and fetal and/or maternal death may occur. Ultrasound has low sensitivity.

images Management is the same as noted above for vaginal bleeding. Emergency delivery may be needed to save the life of the fetus and/or mother. Avoid tocolytics.

PLACENTA PREVIA

images Placenta previa is the implantation of the placenta over the cervical os.

images Risk factors include multiparity and prior cesarean section.

images Clinical features include painless bright-red vaginal bleeding.

images Diagnosis is made by transabdominal pelvic ultrasound. Transvaginal US and pelvic examinations are contraindicated.

PREMATURE RUPTURE OF MEMBRANES

images Premature rupture of membranes (PROM) is rupture of membranes prior to the onset of labor.

images Clinical presentation is a rush of fluid or continuous leakage of fluid from the vagina.

images Diagnosis is confirmed by finding a pool of fluid with pH >7.0 (dark blue on nitrazine paper) in the posterior fornix, and ferning pattern on smear. Sterile speculum examination may be done; if possible, digital pelvic examination should be deferred or done with sterile gloves.

images Test for the presence of chlamydia, gonorrhea, bacterial vaginosis, and group B streptococci infections. Perform ultrasound to assess fetal age, weight, anatomy, amniotic fluid level.

images Patients with suspected PROM require obstetrics (OB) consultation for admission and possible delivery based on gestational age and possible antibiotics.

PRETERM LABOR

images Preterm labor is defined as labor prior to 37 weeks’ gestation. It occurs in 10% of deliveries and is the leading cause of neonatal deaths.

images Risk factors include PROM, abruptio placentae, drug abuse, multiple gestation, polyhydramnios, incompetent cervix, and infection.

images Clinical features include regular uterine contractions with effacement of the cervix. The diagnosis is made by observation, with external fetal monitoring (initiated without delay) and serial sterile speculum examinations.

images Consult an obstetrician for admission and decision regarding tocolytics. If tocolytics are initiated, the mother should receive glucocorticoids to hasten fetal lung maturity (two doses of betamethasone 12 milligrams IM 24 hours apart or four doses of dexam-ethasone 6 milligrams IM 12 hours apart). Do not use tocolytics if abruptio placentae is suspected.

images Gestational age less than 34 weeks is associated with poorer outcomes; consider transfer to a tertiary care center with a high-risk intensive care unit if possible.

HYPERTENSION, PREECLAMPSIA, AND RELATED DISORDERS

images Hypertension in pregnancy may be chronic due to preexisting hypertension or gestational (preeclampsia, eclampsia and transient hypertension of pregnancy).

images Complications associated with hypertension in pregnancy include HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome, abruptio placentae, preterm birth, and low-birth-weight infants.

images Preeclampsia complicates 5% to 10% of pregnancies.

images The following associated findings may or may not be present in patients with preeclampsia:

image Proteinuria

image Oliguria

image Headache or visual disturbances

image Epigastric, and/or RUQ pain

image Pulmonary edema or cyanosis

image Hemolysis

image Elevated liver enzymes

image Thrombocytopenia

images HELLP syndrome often presents with abdominal pain; consider it in differential of pregnant women (at >20 weeks’ gestation) with abdominal pain. Diagnosis is made by lab tests: schistocytes on peripheral smear, platelet count less than 150,000/mL, and elevated liver function tests. Obtain CBC, urinalysis, electrolyte panel, liver panel, and coagulation profile.

images Consult an obstetrician and initiate immediate continuous fetal monitoring.

images Hypertension treatment usually reserved for patients with BP >160 systolic and >110 diastolic: labetalol 20 milligrams IV as the initial bolus, with repeat boluses of 40 to 80 milligrams, if needed, to a maximum of 300 milligrams. A second option is hydrala-zine 5 to 10 milligrams IV initially, followed by 5 to 10 milligrams IV every 10 minutes. Eclampsia is treated with a magnesium sulfate loading dose of 4 to 6 grams over 20 minutes, followed by a maintenance infusion of 1 to 2 grams/h to prevent seizure. Serum magnesium and reflexes must be monitored. Definitive treatment requires delivery of the fetus.

EMERGENCIES DURING THE POSTPARTUM PERIOD

images Hemorrhage and infection are the most common post-partum complications presenting to the ED.

images Postpartum preeclampsia or eclampsia, amniotic fluid embolism, and postpartum cardiomyopathy are rare but life-threatening complications.

images Thromboembolic disease is common in the postpartum period.

POSTPARTUM HEMORRHAGE

images The differential diagnosis of postpartum hemorrhage includes uterine atony (most common), uterine rupture, laceration of the lower genital tract, retained placental tissue, uterine inversion, and coagulopathy.

images After the first 24 hours, retained products of conception, uterine polyps or coagulopathy, such as van Willebrand disease are more likely causes.

images The uterus is enlarged and “doughy” with uterine atony. A vaginal mass is suggestive of an inverted uterus. Bleeding in spite of good uterine tone and size may indicate retained products of conception or uterine rupture.

images Manage hemorrhage with crystalloid IV fluids and/or packed red blood cells if needed. Obtain CBC, clotting studies, and type and cross-match.

images Treatment of uterine atony consists of uterine massage, removal of the placental remnants and oxy-tocin 10 units IM or 40 units in 500 mL of IV solution given over 20 to 30 minutes until bleeding is controlled.

images Treatment of retained products of conception requires removing all placental remnants form the uterus. Ultrasound can help identify the retained material.

images When clinically significant bleeding continues despite taking the above measures, consult interventional radiology (if available) to identify and embolize the involved pelvic arteries.

images Minor lacerations may be repaired using local anesthetic. Extensive lacerations, retained products of conception, uterine inversion, or uterine rupture require emergency operative treatment by the obstetrician.

INFECTION

images Postpartum endometritis is usually polymicrobial. Risk factors include cesarean delivery, prolonged ruptured membranes or labor, younger maternal age, and internal fetal monitoring.

images Clinical features include fever, lower abdominal pain, foul-smelling lochia, uterine and cervical motion tenderness, and varying amounts of discharge. Obtain CBC, urinalysis (usually cath), and cervical cultures.

images Admission for antibiotic treatment is indicated for most patients.

images Antibiotic regimens include gentamicin 5 miligrams/kg IV plus clindamycin phosphate 2700 milligrams IV q24 hours or piperacillin/tazobactam, 3.375 grams IV plus gentamicin, 5 milligrams/kg. (French LM, Smaill FM. Antibiotic regimens for endometritis after delivery. Cochrane Database Syst Rev. 2004;4: CD001067.)

AMNIOTIC FLUID EMBOLISM

images Amniotic fluid embolism is a sudden, catastrophic illness with mortality rates of 60% to 80%.

images Clinical features include respiratory distress, altered mental status, profound hypotension, coagulopathy and seizures.

images Intensive management for cardiovascular collapse and DIC is indicated.

MASTITIS

images Mastitis is cellulitis of the periglandular breast tissue.

images Clinical features include swelling, redness, and tender engorgement of the involved portion of the breast. Ultrasound may help differentiate between mastitis and abscess.

images Initiate treatment with dicloxacillin 500 milligrams orally four times daily or cephalexin 500 milligrams orally four times daily. Clindamycin 300 milligrams PO every 6 hours may be used in patients with penicillin allergy or if concerns about MRSA exist.

images Oral analgesics may be needed.

images Patients should continue nursing on the affected breast.


For further reading in Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 6th ed., see Chapter 106, “Emergencies During Pregnancy and the Postpartum Period,” by Gloria J. Kuhn.




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