Appendix: Answers to Multiple Choice Questions
CHAPTER 2
1A. Beneficence and nonmaleficence are synonyms
2E. Both A and C are true
3C. Technical skills
4D. Are separate organizations that credential surgeons, and educate surgeons, respectively, as primary parts of their missions
5E. A, B, and C
CHAPTER 3
1A. Is an approach to categorizing patients preoperatively to assess their risk for an operative procedure
2D. Should include a pain assessment to aid in the management of postoperative pain
3C. Can be modified by risk-based interventions
4E. Both A and C are true
5C. Can have frailty measured by a variety of means that predict the risk of complications
CHAPTER 4
1E. Hypocalcemia
2D. Discharge the patient with a prescription for pain medication and a plan for follow-up in 2 weeks
3C. Cancel the operation with the plan for improved preoperative preparation
4E. All of the above except for D
5D. Evaluation of the patient, intubation for protection of airway, transfer to a higher level of care, transfusion with 2 units of FFP and 2 units of matched packed RBCs, antibiotic administration, and computed tomography of the abdomen
CHAPTER 5
1A. They are common after chest procedures, but rare after abdominal operations.
2C. Her initial management can include intravenous hydration and nasogastric suction.
3C. High ileostomy output with inadequate postoperative replacement
4D. Bladder pressure measurement may be useful to determine the likelihood of abdominal compartment syndrome.
5A. Classified by the Centers for Disease Control into: (1) wound only, (2) organ space, and (3) involving organ parenchyma
CHAPTER 6
1B. Inflammation. An acute wound is defined by its ability to normally progress, in a predictable and timely manner, through all of the phases of wound healing; coagulation, inflammation, fibroplasia, angiogenesis, and remodeling. A protracted inflammatory phase is the usual mechanism for the formation of a chronic wound. All clinical efforts should be made to reduce chronic wound inflammation in an effort to support healing.
2C. Macrophage. The macrophage is the most important source of growth factor signals for wound healing. Experimental studies show that wound healing is most impaired in the absence of macrophages. Although fibroblasts are the main source of collagen synthesis and endothelial cells are required for revascularization, they are dependent on macrophage signaling to stimulate and direct tissue repair. A platelet is not a cell.
3E. TcO2 less than 30 mm Hg. Wounds will not heal when the tissue concentration of oxygen falls below 30 mm Hg. It is the most powerful predictive measure of delayed or impaired wound healing. Vitamin C deficiency may result in impaired collagen cross linking (scurvy) and weak scars. Low serum albumin predicts increased wound complications, like wound infection. The microangiopathy of radiated tissue indirectly reduces perfusion and therefore, TcO2 levels. Finally, smoking impairs wound healing through the vasoconstrictive effects of chronic nicotine and relative hypoxia as well.
4C. A moist wound environment. A moist or even wet wound environment is critical to normal wound healing. The cellular and molecular biological activity within a wound requires hydration to proceed. Clinical use of dry dressings to support wound debridement, for example, should be limited. Similarly, poor dressing resulting in repeated trauma and mechanical instability to the wound is often overlooked as a source for wound healing failure. Wound infection is the most clinically important, and expensive, impediment to surgical wound healing. Foreign bodies in the wound, such as synthetic surgical meshes, also delay normal wound healing. Finally, experimental and clinical data support that obesity contributes to abnormal wound healing, primarily through a metabolic pathway, and secondarily by increasing the risk of wound infection.
5D. Early fascial dehiscence and wound failure. Pollock and Evans showed in a classic clinical study that 94% of incisional hernias were the result of 1.2 cm fascial dehiscence before POD 30. The majority of the time, these were clinically occult wound closure failures, progressing to incisional hernias over the subsequent 3 years. It is no longer believed that many incisional hernias are the result of abnormal scar formation or suture breaking, stretching or even pulling through the fascia. Poor technique certainly will contribute to incisional hernia formation, but the fundamental mechanism is early fascial dehiscence.
CHAPTER 7
1B. In bipolar electrosurgery, the current flows from the handpiece to the return electrode.
2B. Depends upon the presence of an oxygen source, an ignition source and fuel
CHAPTER 8
1E. All of A, B, and C
2E. Both A and C are true
3C. Can be improved by the use of alcohol-containing skin preparation solutions
4E. Both A and C
5A. NSSSIs are generally self-limited and non- threatening
CHAPTER 9
1C. Anion gap metabolic acidosis with appropriate respiratory compensation. As above, values from an arterial blood gas are typically reported in this order: pH, pCO2, paO2, HCO3–.
This patient’s pH is normal, but near-acidotic. HCO3– and pCO2 are both low. Decreased HCO3– will cause acidosis, while decreased pCO2 will cause alkalosis, thus the patient’s primary disorder is metabolic. His calculated anion gap is 22. pCO2 is within the 36-40 mm Hg range of appropriate compensation predicted by Winter’s formula, thus no concurrent respiratory disorder exists. Therefore, this patient has an anion gap metabolic acidosis with appropriate respiratory compensation. Respiratory compensation for metabolic disorders is rapid (note his hyperventilation), hence the normal pH.
If respiratory compensation were inappropriate, one would need to consider another, simultaneous process, in addition to alkalosis, eg, the respiratory acidosis which occurs in the later stages of salicylate poisoning, when central respiratory drive has been suppressed.
Note the patient’s ΔΔ = 2.5. Considering this finding in isolation, one would conclude that the patient has a mixed anion-gap metabolic acidosis and metabolic alkalosis. This underscores the need to take into account all of the patient’s data when making determinations of acid-base status. There is no additional evidence of a metabolic alkalosis, thus this additional disturbance is unlikely.
2A. Hypophosphatemia. Refeeding syndrome occurs when a malnourished patient (eg, an elderly or alcohol-dependent patient, or a patient who has experienced recent weight loss) begins to consume calories or begins to receive intravenous glucose administration. Insulin levels rise, causing electrolytes which have shifted to the extracellular space during a period of starvation to shift back to the intracellular space for use in the construction of new proteins and cells. Refeeding also leads to increased intracellular requirements for PO43– and Mg2+ due to increased ATP production and glucose metabolism, decreasing serum levels of these electrolytes even further. This all leads to hypokalemia, hypomagnesemia, and hypophosphatemia, any one of which may be fatal. For these reasons, electrolytes must be closely monitored and aggressively repleted in patients at risk for refeeding syndrome.
3C. FENa < 1%. In oliguric patients, FENa < 1% is indicative of pre-renal azotemia and intravascular volume depletion. BUN:Cr ratio > 20 is indicative of hypovolemia. FENa > 1% is indicative of intrinsic renal causes of oliguria, and should prompt workup including microscopic urine analysis and renal ultrasonography. Post-renal obstruction should be investigated if clinically suspected (eg, caused by benign prostatic hypertrophy in this 70-year-old male).
FENa is unreliable in patients taking diuretics. In such cases, FEUN should be calculated:
where U: urine, P: plasma, UN: urea nitrogen, BUN: blood urea nitrogen, Cr: creatinine.
Table 9–5. Common laboratory values distinguishing between oliguric pre-renal and intrinsic renal failure.
4D. All of the above. Stored blood products are anticoagulated with trisodium citrate, which chelates Ca2+ from stored blood, disrupting the clotting cascade. In the setting of massive transfusion, such as this patient has undergone, normal hepatic metabolism of trisodium citrate may be overwhelmed, and Ca2+ (along with Mg2+) may be chelated from the blood, leading to hypocoagulability, hypocalcemia, and hypomagnesemia. Furthermore, stored pRBCs contain high levels of K+, the result of lysis of red blood cells. This is especially true of the older pRBCs often utilized in massive transfusion situations. For these reasons, serum electrolytes must be closely monitored and controlled in the setting of massive transfusion.
5B. Mixed metabolic alkalosis and AG metabolic acidosis. The patient is acidotic, with a normal pCO2, low-normal HCO3–, and high anion gap. Therefore, this patient has an anion-gap metabolic acidosis. Given the clinical circumstances, the most likely etiology of her metabolic acidosis is lactic acidosis caused by septic shock.
Note that the patient’s pH is significantly below the lower limit of normal, despite the normal pCO2 and low-normal HCO3–. This should prompt concern for a mixed acid-base disorder. Her ΔΔ = 2, indicating a coexistent metabolic alkalosis. The several days of gastric suctioning provides a ready explanation for this component of her mixed acid-base disorder.
CHAPTER 10
1C. Bactericidal activity of enteral nutrition components. Multiple mechanisms have been proposed for the morphological and functional differences observed in the intestinal epithelium with parenteral nutrition (PN) when compared to enteral nutrition. It has repeatedly been demonstrated that small bowel mucosal mass is lost with only PN. Yang and colleagues demonstrated that the administration of 25% enteral nutrition reversed the abnormal IL-10, IL-4, and IL-6 messenger RNA (mRNA) expression that had resulted from only PN support in animal models. This is of particular significance as these changes in cytokine expression were associated with epithelial leak and an increased rate of enterocyte apoptosis.
It has also been shown that the type and route of nutrition affect pIgR expression in an organ-specific manner; pIgR represents the exclusive transport pathway for IgA to move from the lamina propria, through the epithelia, into the lumen of the gut where it acts as a key component in the gut’s defense. Enteral nutrition components are not bactericidal and actually help preserve normal flora.
2D. Burns. Energy requirements above basal needs are approximately 10% for elective operations, 10%-30% for trauma, 50%-80% for sepsis, and 100%-200% for burns. Burns covering more than 40% total body surface area (TBSA) are typically followed by a period of severe stress, characterized by an exaggerated catabolic state. Increases in catecholamine, glucocorticoid, glucagon, and dopamine secretion are thought to initiate the cascade of events leading to the acute hypermetabolic response with its ensuing catabolic state. Appropriate nutrient delivery can be accomplished by feeding 1.2-1.4 times the measured resting energy expenditures (REEs).
3C. The recommended amino acid dose ranges from 0.8 to 1 g/kg. The recommendation for the amino acid dose ranges from 1.2 to 1.5 g/kg/d for most patients with normal renal and hepatic function, although some sources recommend higher doses. TPN via a central line is indicated for patients who cannot obtain adequate nourishment via the gastrointestinal tract for a minimum duration of treatment of 7-10 days. The use of postoperative TPN for only 2 or 3 days is highly discouraged, as the risks outweigh the benefits incurred over this short period of time. A reasonable initial guideline is to provide 60%-70% of nonamino acid calories as dextrose and 30%-40% of nonamino acid calories as fat emulsion. The placement of central line catheters always carries risks; the overall complication rate related to this access is greater than 15%. Femoral vein access carries the highest risk of infection and should be avoided if possible.
4C. Gastric bypass patients are prone to deficiencies of the fat-soluble vitamins, calcium, iron, vitamin B12, and folate. Gastric bypass procedures intentionally limit the amount of oral intake and decrease the amount of small bowel that takes part in absorption. This renders the population of patients prone to deficiencies of the fat-soluble vitamins (A, D, E, and K), calcium, iron, vitamin B12, and folate.Careful attention should be paid to ensuring that these deficiencies are countered with supplementation. Technical complications occur in about 5% of enterally fed patients and include clogging of the tube; esophageal, tracheal, bronchial, or duodenal perforation; and tracheobronchial intubation with tube feeding aspiration. Lactose intolerance is least common in European Caucasians, present within only 5%-10% of this population. Although recommendations differ depending on source, enteral feeds are not typically held until gastric residuals of greater than 200 cc are encountered.
5B. The NRI is an excellent tool for tracking the adequacy of nutritional support. The NRI is an index that has been prospectively crossvalidated against other nutritional indices with good results, but is not a good tool for tracking the adequacy of nutritional support, since supplemental nutrition often fails to improve serum albumin levels. The index successfully stratifies perioperative morbidity and mortality using serum albumin and weight loss as predictors of malnutrition.
CHAPTER 11
1D. Stop all over-the-counter herbal remedies. Although the use of herbal medications has been around for many years, none have been approved by the FDA. Many times the pharmacology of these remedies is unknown and the remedies may not contain the correct amounts of active ingredients stated on the label. It is estimated that up to 12% of patients are using these herbal drugs.
2B. The initial assessment should be done at a minimum the day before surgery for patients undergoing procedures of high surgical invasiveness. The timing of the preoperative evaluation by an anesthesiologist depends primarily on the planned degree of the surgery. Even healthy patients undergoing a surgical procedure that involves a high degree of surgical invasiveness that may include the risks of a high volume of blood loss, prolonged surgical time, special positioning requirements, etc, should be seen at least a day before the planned procedure. Patients with significant comorbidities should be seen in a PAC at least the day before surgery no matter the degree of surgical invasiveness as it is necessary to ascertain the degree of control of the comorbidities.
3D. Surgery should be delayed for up to 1 year. The risk of stent thrombosis makes it necessary to place patients who have had a drug-eluting stent placed on antiplatelet agents such as clopidogrel and aspirin. Stopping these drugs prematurely to allow for the performance of an elective surgical procedure requires careful consideration of the risk of bleeding as well as the risk of stent thrombosis if the antiplatelet agents are both stopped. At a minimum aspirin should be continued. Emergent procedures that involve a high risk of bleeding require that the clopidogrel be stopped, but continuing the low-dose aspirin is recommended.
4D. None of the above. There is no way to be 100% of preventing intraoperative awareness. Anesthesiologists performing strict equipment check before beginning an anesthetic to ensure that vaporizers have sufficient agent levels, that there is an agent concentration monitor as part of the anesthesia monitoring system, and frequent observation that IV lines are patent and intact when intravenous medications are used is one way to eliminate the preventable components. Stable vital signs throughout a case are not always a reliable sign that a patient may not suffer from intraoperative awareness. Finally the processed EEG BIS monitor has been shown to be no more effective in preventing awareness than careful monitoring of end-tidal agent concentration.
5C. Obesity. The RCRI factors of (1) ischemic heart disease, (2) heart failure, (3) high-risk surgery, (4) diabetes mellitus, (5) renal insufficiency, and (6) cerebral vascular diseases are a validated set of independent predictors of cardiac risk for patients. There RCRIs were derived from a single-center prospective group of patients undergoing elective major noncardiac surgery. The anesthesiologist in a pre-op clinic will screen for these factors and recommend further studies based on the presence or absence of RCRIs. Patients with no RCRIs had a very low (0.4%) cardiac risk while patients with three or more risk factors have a 5.4% risk of an adverse cardiac event and warrant further testing or optimization of the factor(s).
CHAPTER 12
1E. All of A, B, and C
2B. Can contribute to coagulopathy
3E. All of A, B, and C
4A. Can be related to products of coagulation and inflammation that are washed out from the damaged tissues
5B. PSV includes a set inspiratory time
CHAPTER 13
1C. Should have an initial assessment including airway, breathing and circulation
2D. Should bypass the trauma room and go directly to the operating room
3E. A, B, and C are all correct
4E. From gunshot wounds below the nipple line typically require laparotomy for evaluation and management
5E. All are correct
CHAPTER 14
1C. Death of others in same incident
2A. Can contribute to coagulopathy
3D. Primary management with bismuth-containing antimicrobial topical agents
4A. Benefits from early consideration with functional position splinting and active motion
5B. Inhalational injury
CHAPTER 15
1B. Take her to the operating room immediately for an emergent biopsy. Invasive fungal sinusitis is usually seen in immunocompromised patients, such as the patient described here. It is caused by uncontrolled infiltrative growth of usually nonpathogenic fungal organisms such as Rhizopus or Aspergillus species. Even with prompt diagnosis, aggressive surgical therapy, and modern antifungal agents, the disease still carries a significant mortality rate (up to 30%). The index of suspicion for invasive fungal sinusitis must be high for any immunocompromised patient, as the symptoms can be subtle and the disease rapidly progressive. If invasive fungal sinusitis is suspected, biopsies should be taken of the suspicious areas and sent for immediate pathologic examination. Note that this can often involve calling a pathologist in from home in the middle of the night or on a weekend, if they are not in-house. In the case presented here, the likelihood of the child cooperating with an examination and biopsy is low, thus an emergent posting to the operating room is the most prudent action.
2E. All of the above. Acute angioedema is characterized by localized swelling of subcutaneous and submucosal tissue of the head and neck. The swelling usually begins with mild facial involvement but may progress to involve the oral cavity, tongue, pharynx, and larynx. The underlying pathophysiology of angioedema involves vasoactive mediators such as bradykinin and histamine, causing interstitial edema through endothelial-mediated vasodilation of arterioles with subsequent capillary and venule leakage. Drug-induced angioedema has classically been associated with the use of angiotensin- converting enzyme inhibitors (ACE inhibitors), although many other medications can also cause this phenomenon. Other drugs known to be associated with angioedema include rituximab, alteplase, fluoxetine, laronidase, lepirudin, angiotensin II receptor blockers (ARBs), and tacrolimus.
3A. Immediately superior to the cricoid cartilage. The patient described has Ludwig’s Angina, an uncommon life-threatening condition characterized by cellulitis involving the submental, sublingual, and submandibular spaces. The source of the infection is odontogenic and spreads rapidly. The infection is usually polymicrobial with aerobic and anaerobic gram-positive cocci and gram-negative rods. Airway compromise in these patients is common, and should be of primary concern. A cricothyroidotomy is performed through the cricothyroid membrane which spans the midline area between the cricoid cartilage inferiorly and the thyroid cartilage superiorly. It can be easily palpated just inferior to the thyroid cartilage in greater than 90% of individuals, and has no major blood vessels or structures. While an emergency tracheotomy can be performed through the second or third intertracheal ring space, this often involves either going through or dissecting part of the thyroid gland off the tracheal wall. As the thyroid’s blood supply is quite robust, the bleeding encountered can be quite significant. Therefore, in an emergency situation the cricothyroid space is almost universally preferred.
4C. Left posterior cricoarytenoid muscle. Innervation to the larynx is provided by the vagus nerve (cranial nerve X). The recurrent laryngeal nerves branch from the vagus nerve and provide motor innervation to all of the intrinsic muscles of the larynx except the cricothyroid muscle. All of the intrinsic muscles of the larynx serve to tense the vocal folds or adduct the vocal folds except one—the paired posterior cricoarytenoid muscles. Current understanding of peripheral nerve injury and regeneration presents the following scenario when the nerve supply to the larynx is injured. After nerve injury, neuronal axon regrowth results in reinnervation of the target muscles but in a random pattern. Since only one of the muscles abducts the vocal folds, reinnervation is unlikely to result in a tonically abducted vocal fold. Instead, the vocal fold usually assumes a paramedian position, accompanied by loss of muscle bulk and atrophy due to loss of innervation. This can lead to hoarseness and vocal fatigue when one side is injured, but often causes airway obstruction if both sides are injured.
5D. 25-year old man with 12 pack-year tobacco history and chronic severe gastroesophageal reflux. Presents with throat pain and dysphagia (trouble swallowing). On fiberoptic endoscopy is found to have a 3 cm ulcerated hypopharyngeal mass. No palpable neck adenopathy is present. Assuming appropriate treatment, outcomes for patients with oral cavity cancer are generally good with 5-year survival rates of 72% for stage I-II, 44% for stage III-IVb, and 35% for stage IVc. Outcomes for patients with laryngeal cancer can be excellent. For early stage I glottis carcinoma (tumor limited to the true vocal folds), 5-year overall survival rates of 90% can be expected. Overall, laryngeal cancer carries a 5-year survival for stage I-II disease of 79%. Survival for oropharyngeal cancer is somewhat worse: stage I-II oropharyngeal cancer 5-year survical average is 58% and stage III-IVb 41%. The hypopharynx is invested with an abundant lymphatic drainage network, and patients with hypopharyngeal cancer typically present with advanced stage disease. Hypopharyngeal cancer carries the worst prognosis of any head and neck subsite. Five-year survival for stage I-II hypopharyngeal cancer is 47%, stage III-IVb is 30%, and stage IVc only 16%.
CHAPTER 16
1D. TSH
2D. Both A and C
3B. Is less likely to spread to lymph nodes than is papillary thyroid cancer
4A. Vitamin A toxicity
5D. Osteoporosis with a T-score of -2.8
CHAPTER 17
1C. Caused at least in part by estrogen stimulation of breast tissue
2D. A personal history of breast cancer
3B. Identifies cancer without node involvement in about 80% of detected cases
4A. A painless mass identified by the patient
5D. Can be reliably detected by sentinel lymph node biopsy in women with clinically uninvolved axillary lymph nodes
CHAPTER 18
1C. Mostly arise from bone or cartilage
2D. Iodine deficiency
3B. Ureteral obstruction with transdiaphragmatic urine leak
4A. Spontaneous bacterial mediastinitis of sarcoidosis
5D. Effectively cured by double lung transplantation with a 10-year graft survival exceeding 85%
Chapter 19A
1C. Atherosclerosis tends to occur diffusely in small coronary vessels. Myocardial tissue extracts 70%-80% of arterial blood oxygen at rest, unlike other organs which can extract additional oxygen during periods of increased demand. The myocardium recruits additional blood flow by vasodilation and recruitment of an extensive capillary bed via a feedback mechanism from adenosine diphosphate and other byproducts of metabolism, increasing oxygen delivery to match consumption. Atherosclerosis, or the formation of intra-arterial cholesterol plaques, tends to occur in the more proximal and larger epicardial vessels, leaving the distal vasculature relatively unobstructed. This allows revascularization by either percutaneous or surgical techniques.
2D. Typical symptoms are exertional dyspnea, angina or syncope. Senile calcific aortic stenosis occurs in the eighth decade of life in patients with tricuspid (normal) aortic valves. While dilation of the ascending aorta is a normal part of the aging process, aneurysms of the ascending aorta are associated with bicuspid aortic valves, related to abnormalities in elastin fiber formation. Rheumatic heart disease affects the mitral valve most commonly. It is unusual for a patient with rheumatic heart disease to present with isolated aortic stenosis but not mitral valve disease, whereas the opposite is fairly common. Indications for surgery in aortic stenosis are the presence of symptoms, which are exercise intolerance, angina, syncope, and dyspnea.
3C. Asymptomatic with a prolapsed anterior mitral leaflet. Indications for surgery in patients with mitral regurgitation include heart failure symptoms, left ventricular dilation and reduced left ventricular systolic function. In asymptomatic patients without symptoms and normal ventricular function and size, surgery could be recommended if the likelihood of durable repair is high. Repair of posterior leaflet prolapse is much more common than in prolapse of the anterior leaflet. Mitral replacement would entail either a bioprosthetic with limited durability, or a mechanical valve and a lifelong requirement for anticoagulation. Moderate mitral regurgitation is typically addressed incidentally at the time of other cardiac surgery, including coronary bypass grafting or aortic valve replacement.
4D. Malperfusion of the abdominal viscera can occur with either Stanford type A or type B aortic dissections. Due to gradual and progressive breakdown of elastin fibers, the ascending aorta dilates as part of the natural aging process. Indications for replacement of the ascending aorta include size of 5-5.5 cm in asymptomatic patients, 4.5 cm in patients with know Marfan syndrome, interval growth of 1 cm in 1 year, or 4.5 cm when incidental to other cardiac surgery including aortic valve replacement or coronary bypass grafting. Stanford type A dissections involve the ascending aorta, which can cause sudden death from intrapericardial rupture and tamponade, aortic valve insufficiency from prolapse, or coronary malperfusion and myocardial infarction. Stanford type B dissections are distal to the ascending aorta and thus not within the pericardial space and not directly adjacent to the aortic valve or coronary ostia. Malperfusion from an aortic dissection occurs when the intimal flap occludes any branch of the aorta causing ischemia. Both Stanford type A and B can cause malperfusion of the abdominal viscera, depending on the extent and geometry of the dissection.
5A. Beta-blockers improve survival in patients with advanced heart failure from a variety of proposed mechanisms, including up-regulation of beta-receptors in the myocardium. Heart failure incidence is increasing related to aging population and the rising incidence of diabetes as well as obesity. Deaths from coronary artery disease and myocardial infarctions are decreasing from improved medical care. Temporary mechanical circulatory support increases a heart transplant candidate to status 1A, while implantable mechanical circulatory support results in status 1B. Patients with chronic heart failure on oral medical treatment are status 2. Following heart transplantation, right ventricular dysfunction is the most frequent complication, as the donor’s untrained right ventricle is required to maintain circulation in a recipient with pulmonary hypertension, which is often present from long standing heart failure.
Chapter 19B
1B. Left-to-right shunting through a VSD causes a volume load on the right ventricle. Ventricular septal defects are classified by their location in the ventricular septum. The most common type is perimembranous. Left-to-right shunting through a VSD causes a volume load on the left ventricle as blood returns from the lungs. The right ventricle does not experience a volume load, but is pressure loaded. Certainly, as PVR decreases after birth, congestive heart failure may develop in a previously asymptomatic patient with a large VSD as left-to-right shunting increases. Knowledge of the expected location of the conduction system is paramount in the surgical repair of a VSD. The AV node is an atrial structure that lies at the apex of an anatomic triangle (known as the triangle of Koch) formed by the coronary sinus, the tendon of Todaro, and the septal attachment of the tricuspid valve. The node then gives rise to the bundle of His, which penetrates the AV junction beneath the membranous septum. The bundle of His then bifurcates into right and left bundle branches, which pass along either side of the muscular ventricular septum. In the presence of a perimembranous VSD, the bundle of His passes along the posterior and inferior rim of the defect, generally on the left ventricular side. The bundle of His tends to run along the posterior and inferior margin of inlet VSDs as well. The conduction tissue is usually remote from outlet and trabecular VSDs.
2A. Neonate with prenatal diagnosis of aortic coarctation who develops acidosis, oliguria, and diminished pedal pulses 8 hours after birth. In scenario A, the neonate described has inadequate systemic perfusion as demonstrated by oliguria and acidosis. With a prenatal diagnosis of aortic coarctation, one must be suspicious at 8 hours after birth that ductal closure has caused a critical narrowing of the aortic isthmus as it involutes. This patient will benefit by reopening the ductus arteriosus with PGE1. The patient described in option B is likely experiencing pulmonary overcirculation with congestive heart failure. Initiating PGE1 would be expected to exacerbate this problem. In option C, a 6-week-old child’s ductus would not be expected to reopen with prostaglandins. Also, the etiology of the heart failure symptoms described is due to myocardial ischemia and surgical correction of the coronary anomaly is required. PGE is not appropriate. In option D, the vascular ring described is likely causing a mechanical airway obstruction. Again, surgical intervention is required. PGE therapy has no role in this situation.
3C. Balloon atrial septostomy. d-transposition of the great arteries typically requires two or more levels of mixing in order to maintain adequate saturations. This may involve mixing at the atrial level (via an ASD), ventricular level (via a VSD), or at the level of the great arteries (via a PDA). In the situation described, the infant requires an additional level of mixing. This may be due to the absence of additional (intracardiac) shunts, or they may be too small if present. Emergent balloon atrial septostomy in the catheterization laboratory is indicated. The other options are not appropriate at this time.
4C. Coronary AV fistula. Coronary AV fistula is the most common major coronary anomaly. The second most common is ALCAPA.
5B. Isolated pulmonary stenosis in a neonate. Isolated aortic coarctation in a neonate is well managed with a primary extended end-to-end anastomosis and is almost always primarily approached surgically. Isolated pulmonary stenosis is typically primarily treated with balloon pulmonary valvuloplasty. This approach has been highly successful. The patient in option C is best managed with a trial of Indocin, followed by bedside surgical ligation if the ductus fails to close with medical management. Larger patients with PDAs requiring closure are frequently treated with catheter-based closure with excellent results. Perimembranous VSDs are best closed surgically. Device closure of VSDs in this location is associated with prohibitively high rates of complete heart block along with the risk of impairing the function of the aortic and/or tricuspid valve.
CHAPTER 20
1A. Absence of esophageal peristalsis. Esophageal manometry is the gold standard for establishing the diagnosis of esophageal achalasia. The classic manometric findings are: (1) absence of esophageal peristalsis and (2) hypertensive LES (in about 50% of patients) that relaxes only partially in response to swallowing. Dysphagia for both solid and liquid food is the most common symptom, experienced by virtually every patient. Heartburn is present in about 40% of patients. As the low intraluminal pH, it is not due to GER, but rather to stasis and fermentation of undigested food in the distal esophagus.
2D. The surgical treatment consists of LES myotomy, resection of the diverticulum or its suspension. Although rare, Zenker diverticulum is more common than the epiphrenic diverticulum. It is a protrusion of pharyngeal mucosa through a weak zone in the Killian’s triangle, secondary to abnormalities of the UES sphincter. Dysphagia occurs very frequently. As the pouch enlarges, its contents can be inhaled into the respiratory tree causing chronic cough and pneumonia. Finally, the established treatment consists of eliminating the functional obstruction performing a UES myotomy, associated with resection or suspension of the diverticulum.
3A. Esophageal manometry, 24-hour pH monitoring and upper endoscopy. Heartburn, along with regurgitation and dysphagia is considered a typical symptom of gastroesophageal reflux (GERD). However, a clinical diagnosis of GERD based on these symptoms is correct in only 70% of patients (when compared with the results of pH monitoring). Heartburn can also be caused by nonesophageal disorders such as biliary disease, irritable bowel syndrome, coronary artery disease, and psychiatric diseases. Esophageal manometry is mandatory to evaluate the function of both the esophageal body and LES. In addition, manometry is essential for proper placement of the pH probe for ambulatory pH monitoring. Twenty-four-hour pH monitoring measures reflux of acid from the stomach into the esophagus and correlate it to the symptoms. Upper endoscopy visualizes the mucosal surface of the esophagus, determines the presence and degree of esophagitis and allows biopsies.
4B. Is linked to duodeno-gastro-esophageal reflux. Barrett esophagus is defined as a change in the esophageal mucosa with replacement of the squamous epithelium by columnar epithelium. It is classified into short segment if less than 3 cm in length or long segment if 3 cm or longer. Barrett esophagus represents an adaptation of the esophageal mucosa to the acid and duodenal juice from the stomach. The diagnosis is confirmed by pathologic examination of the esophageal mucosa and requires the identification of goblet cells, typical for intestinal epithelium. Patients with BE have typically a long history of GERD. Nevertheless, they may become asymptomatic over time due to the decreased sensitivity of the metaplastic epithelium.
5D. All of the above. In patients with early esophageal cancer (pT1a), an esophagectomy can be avoided, because of the very low risk of lymph nodes metastasis (0%-3%), and EMR and RFA are very effective. Unlike intramucosal cancer (T1a), T1b cancer has a high risk of lymph node metastases (20%-30% vs. 0%-3%), and therefore esophageal resection is the treatment of choice. In case of locally advanced esophageal cancer (T3-4N0-3, T2N1-3), chemo-radiation is the best treatment, followed by surgery. It seems that the combination of neoadjuvant therapy followed by surgery offers the best survival benefit. This is particularly true in the subgroup of patients (about 20%) who have a “complete pathologic response” (no tumor found in the specimen). In patients with distant metastases, survival is very poor and treatment modalities focus on the palliation of symptoms. Endoscopic stenting is one of the most successful options in the treatment of dysphagia.
CHAPTER 21
1C. Appendicitis. Both the patient’s age and gender play an important role in forming the differential diagnosis. As patients age there is a distinct shift in causes of abdominal pain and an increase in surgically treatable etiologies. This has been best documented in the OMGE’s (World Organization of Gastroenterology) survey of worldwide causes of abdominal pain. This survey gathered data on more than 10,000 patients in 17 countries presenting with acute abdominal pain. When the data is segregated by age comparing those less than 50 years of age to those older than 50 years of age there are clear differences. Appendicitis is by far the most common etiology of a surgical abdomen in patients younger than 50. In the older population group cholecystitis is the most common cause with good representation from bowel obstruction, appendicitis, pancreatitis and diverticulitis. In older patients hernias are a more common problem, with up to a third of bowel obstructions being related to hernias. Cancer, vascular disease, and mesenteric ischemia are also more common as we age. While it is more common for a patient in their twenties to present with abdominal pain, a large proportion will have the diagnosis of nonspecific abdominal pain. Patients older than 50 years of age have both a higher likelihood of an operative etiology for their acute abdomen as well as an increased mortality related to their presentation. This mortality is higher still for patients older than 70 years of age.
2B. They are most useful when intestinal obstruction is part of the differential diagnosis. Before the advent of the CT scan the acute abdominal series played an important role in the diagnosis of the acute abdomen as diagnostic tools were limited. There are long lists of radiologic findings that may correlate with a wide variety of intra-abdominal pathology. A small percentage of renal and biliary stones may be seen on plain radiograph. In our current practice environment there is a much more limited role for plain films of the abdomen. They can be helpful in locating foreign bodies within the GI tract and they may assist in the diagnosis and evaluation of bowel obstructions. Ultrasound is a more sensitive test for biliary stones. CT scans have increased sensitivity and specificity in almost all causes of intra-abdominal pathology when compared with abdominal plain films. For this reason, in stable patients who are going to undergo CT scan there is little added value in obtaining plain films. Upright chest radiograph is the most sensitive test for intra-abdominal free air from a perforated viscus. It should be obtained as part of the evaluation of the acute abdomen both for identifying free air as well as ruling out a variety of cardiac and pulmonary pathologies.
3E. ABG and Lactate. Given the severity of the patient’s pain and its abrupt presentation it would not be prudent to solely admit this patient without further evaluation. This patient presents with severe acute abdominal pain and a relatively benign abdominal examination, concerning for mesenteric ischemia. Etiologies include arterial or venous occlusion as well as nonocclusive low-flow states such as in critically ill with hypotension. This patient has an irregular heart rate from atrial fibrillation, which puts the patient at risk for an arterial embolic event. The classic presentation of mesenteric ischemia is severe pain out of proportion to physical examination findings. Helpful laboratory data include an arterial blood gas with lactate. An elevated lactate suggests tissue hypoxemia. Ischemic bowel as a result ofdiminished blood flow will convert to anaerobic metabolism on a cellular level producing lactate. Although not specific to mesenteric ischemia, it can be a helpful laboratory value to predict severity of illness when elevated. A normal lactate does not exclude mesenteric ischemia. If clinically suspected, workup should proceed despite a normal lactate. Radiographic imaging of choice is CT angiography to assess mesenteric vessels. These patients should be kept strict NPO and if mesenteric ischemia is diagnosed, patient should proceed emergently to the operating room for exploratory laparotomy to minimize further bowel ischemia. Amylase is helpful in ruling out other diagnostic possibilities such as pancreatitis. As mentioned earlier plain abdominal films are rarely indicated in evaluation of the acute abdomen.
4C. MRI abdomen/pelvis. Pregnancy presents a diagnostic dilemma when encountering abdominal pain. Ultrasound is the first line imaging modality in pregnant women as it is noninvasive and does not involve radiation; however, ultrasound often will be equivocal or indeterminate in diagnosing appendicitis. If ultrasound is nondiagnostic, MRI is preferred to CT scan for the evaluation of acute appendicitis in pregnancy. MRI avoids ionizing radiation, making it a safer imaging modality for the fetus. Both laparotomy and laparoscopy are considered safe in pregnancy. Early operative intervention in appendicitis during any trimester is warranted as ruptured appendicitis is associated with higher rates of fetal mortality, maternal mortality, and preterm delivery. Given the operative risks of the procedure (fetal loss, early labor) and the risks of delayed diagnosis (ruptured appendicitis, fetal loss) when possible confirmation of diagnosis is preferred before proceeding to the OR and patients are rarely simply observed.
5D. A 65-year-old man with 1 day of mild abdominal pain and reports of bright red blood per rectum. Normotensive, but hematocrit on admission 24% (baseline Hct 42%). There are several pathways in the management of patients with an acute abdomen. There is a subset of patients who require immediate operative intervention including ruptured abdominal aortic or visceral aneurysms, splenic or hepatic adenoma rupture, ruptured ectopic pregnancy, and major abdominal trauma. These patients may be recognized by their hemodynamic instability. Another cohort of patients will present with urgent operative indications. In this group there is often enough time for diagnostic testing to confirm the diagnosis, but once confirmed the patient should proceed expeditiously to the operating room. Conditions requiring urgent intervention include perforated hollow viscus, acute appendicitis, diverticulitis (perforated), mesenteric ischemia, and strangulated hernias. A third group of patients include those who will need operative intervention on the same admission (12-48 hours) but not urgently. Early intervention would be for patients with uncomplicated cholecystitis, or incarcerated hernias. Several diagnoses should be observed on surgical services but may not require operative intervention. This group includes patients with uncomplicated bowel obstructions, uncomplicated diverticulitis, and symptomatic cholelithiasis. These patients may require operative intervention if they fail to improve with nonoperative management. Lastly diseases such as pancreatitis, inflammatory bowel disease, peptic ulcer disease, endometriosis, and gastritis may cause significant abdominal pain but usually respond to nonoperative therapies and usually do not require operative intervention. The lower GI bleeding is preferentially treated with colonoscopy and resuscitation. It rarely requires urgent operative intervention and only in those patients with hemodynamic instability who have failed conservative management. When the cause of abdominal pain is uncertain despite diagnostic testing a judgment must be made as to whether the patient merits inpatient monitoring or can be further evaluated as an outpatient.
CHAPTER 22
1D. Is divided anatomically into parietal and visceral components
2D. Is most frequently associated with cirrhosis and ascites
3B. That often originates from gastrointestinal sources
CHAPTER 23
1D. May include a posterior gastric artery that is typically a branch of the splenic artery
2D. It is the site of the assembly of micelles for nutrient absorption
3B. Cannot be done by Billroth I reconstruction after total gastrectomy
4A. Can impair the appropriate relaxation of the pylorus
5C. Initially includes gastric decompression and acid suppression
CHAPTER 24
1D. A replaced right hepatic artery typically arises from the inferior mesenteric artery and courses posteriorly and to the right of the common bile duct within the porta hepatis
2D. Serum sodium
3B. With a laceration 4-cm deep but not affecting the major vasculature is a Grade III lesion
4A. In the United States, is most often caused by cirrhosis
5C. Should include controlling hemorrhage as expediently and simply as possible
CHAPTER 25
1D. Oral cholecystography
2D. Intestine
3B. Are nearly always present in people with chronic cholecystitis
4A. Diverticulitis
5C. Should usually include draining the biliary tree
CHAPTER 26
1D. The uncinate process lies anterior to the superior mesenteric artery
2D. Parotid gland
3B. Can be complicated by pancreatic abscess
4A. Is unresectable at the time of diagnosis in most people
5C. Should usually include resection of the primary tumor
CHAPTER 27
1D. The gastrosplenic ligament carries the short gastric vessels.
2D. Both A and C
3B. Is at greatest risk in young children
CHAPTER 28
1D. The appendix is fixed retrocecally in 65% of adults
2D. A, B and C
3B. Are most commonly neuroendocrine (carcinoid) tumors
CHAPTER 29
1A. Intra-abdominal adhesions. Sixty percent to 75% of cases of mechanical SBO are secondary to adhesions, related to prior abdominal surgery. Lower abdominal and pelvic surgery appears to be associated with a higher incidence of adhesions than the upper abdominal surgery. Congenital bands are rarely seen in children.
2D. All of the above. A nasogastric tube should be inserted early in order to relieve symptoms, avoid aspiration, and monitor the fluid and electrolyte losses. Depending on the level and duration of obstruction, fluid and electrolyte deficit vary. The exact volume of fluid and electrolytes must be calculated individually for each patient. In some cases, in which there is preoperative evidence of free space in the abdomen for the trocar placement, laparoscopy finds a good indication. Laparoscopic adhesiolysis reduces the risk of further adhesions thanks to the reduced peritoneal trauma.
3C. Deep venous thrombosis can be a cause. Acute mesenteric ischemia is characterized by severe and diffuse abdominal pain that is often unresponsive to narcotics. Mesenteric arterial embolism accounts for about 50% of cases. The main cause is atrial fibrillation. Venous thrombosis can be a consequence of venous stasis (as in portal hypertension) or hypercoagulability (congenital disorders, oral contraceptives).
Deep venous thrombosis may cause pulmonary embolism but not mesenteric thrombosis.
4D. Carcinoid syndrome develops in the presence of liver metastases. Adenomas are the most common benign tumors of the small intestine. The duodenum is the most common site of involvement, and the lesion most commonly noted is the villous adenoma. These lesions tend to involve the region of the ampulla of Vater. Malignant tumors tend to increase in frequency from proximal to distal, with the exception of adenocarcinomas which are most frequent in the duodenum. Adenocarcinoma is the most common histologic type (45%), followed by carcinoids (30%), lymphomas (15%), sarcomas, and GISTs (10%). Peutz–Jeghers syndrome is characterized by diffuse gastrointestinal hamartomas and mucocutaneous pigmentation. The malignant potential of this polyposis is very small.
Carcinoid tumors produce symptoms secondary to hormone production, including hot flashes, bronchospasms and arrhythmias. This constellation of symptoms, called carcinoid syndrome, occurs when the liver is not able to metabolize the active substances produced by the carcinoid tumor.
5A. Ileosigmoid fistula is a common complication of perforating CD of the terminal ileum. Typically, the inflamed terminal ileum adheres to the sigmoid colon that is otherwise healthy. Ileovesical fistulae occur in approximately 5% of CD patients. Although hematuria and fecaluria are virtually diagnostic of ileovesical fistula, these symptoms are absent in almost 30% of cases. Enterovaginal and ECF are rare fistulas caused by perforating small bowel disease draining through the vaginal stump in a female who has previously undergone a hysterectomy or through the abdominal wall, usually at the site of a previous scar.
CHAPTER 30
1D. Inferior hypogastric plexus near Denonvillier fascia
2C. Bowel rest, intravenous fluids, broad spectrum antibiotics, and percutaneous drainage
3D. Exploratory laparotomy
4D. Right hemicolectomy
5C. Dehydration
CHAPTER 31
1D. Infralevator
2D. Anal fissure
3B. Is an intussusception of the rectum
4A. Are typically treated with a regimen of chemotherapy and radiation therapy after diagnosis
5C. Can include palliation of macroscopic lesions my operation
CHAPTER 32
1D. A tension free repair. A tension free repair is the key factor in successful repair of all groin hernias. Although a tension-free repair can be accomplished by using a relaxing incision in the traditional tissue repairs, the use of mesh for either an open or laparoscopic repair obviates the need for a relaxing incision. Although decreasing the size of the internal ring will help prevent recurrence of an indirect inguinal hernia, it is not sufficient to prevent a recurrence through the transversalis fascia if a strong, tension-free repair is not accomplished.
2E. The use of the inguinal ligament in the repair. Keys to successful repair of a femoral hernia include the knowledge that the femoral canal lies beneath the inguinal ligament. For this reason, the repair must be performed to Cooper’s ligament or the iliopubic tract, which lie deep to the inguinal ligament. The repair must result in obliteration of the hernial defect, whose medial border is the stiff lacunar ligament, superior border is the inguinal ligament, and lateral border is the femoral vein; these structures do not lend themselves to primary repair with sutures. After the contents of the hernia sac are reduced and the sac excised, either mesh or tissue is used to cover the defect in a tension-free manner. If a tissue repair is used, a vertical relaxing incision in the anterior rectus sheath is necessary to prevent tension on the repair. If a laparoscopic or open mesh repair is elected, the defect in the transversalis fascia must be covered completely.
3A. Equivalent recurrence rate of open and laparoscopic hernia repairs with mesh in the hands of experienced surgeons. Although early trials of open and laparoscopic mesh hernia repairs showed higher recurrence with laparoscopic repairs, more recent randomized trials involving surgeons with greater laparoscopic experience show equivalent recurrence rates for mesh repair performed open or laparoscopically. Perioperative complications are higher with extraperitoneal laparoscopic procedures than other repairs, as are recurrence rates, compared to laparoscopic transabdominal or open techniques. Laparoscopic repairs are generally associated with less pain and numbness long-term than open repairs.
4C. Develop a wound infection. Several comorbidities have been demonstrated to increase the risk of incisional hernia formation after an abdominal operation: poor surgical technique, advanced age, obesity, pulmonary disease, smoking, diabetes, previous radiation, blood loss greater than 1000 mL, poor nutrition, steroid use, and immunocompromise. The greatest risk of incisional hernia, as high as 80%, is found in patients who develop a wound infection.
5E. Underlay of biologic mesh with primary tissue brought to midline. For all but the very smallest (< 2 cm) hernias, primary repair carries an unacceptable recurrence rate. Similar poor results are seen with inlay mesh repair, whether synthetic or biologic mesh is used. Synthetic mesh has high infection risk when bowel must be resected and should not be used under these circumstances. The best results in a contaminated field are seen with an underlay of biologic mesh with the patient’s primary tissue brought together in the midline.
CHAPTER 33
1A. Laparoscopy. Laparoscopic adrenalectomy is safe for small adrenal tumors. Large incisions are not necessary for most adrenal tumors and are associated with more morbidity.
2A. Plasma-free metanephrines. Plasma-free metanephrines or 24-hour urinary fractionated metanephrines are the most sensitive and specific test for diagnosis of pheochromocytoma/paraganglioma.
3C. Fine-needle biopsy of the adrenal tumor. Fine-needle biopsy of an adrenal tumor is almost never necessary, is associated with significant false positive and false negative results, can be dangerous (for pheochromocytoma) and risks seeding of tumor (adrenocortical cancer).
4B. A feminizing tumor. Feminizing adrenal tumors are rare, large, and almost always adrenal cortical cancer. Laparoscopic resection would be both difficult and risk local recurrence and seeding of the cancer. In contrast, metastatic cancer to the adrenal gland can usually be resected safely by laparoscopy.
5E. 5-HIAA. Adrenal tumors do not secret 5-HIAA as do some carcinoid tumors.
CHAPTER 34
1D. Typically occurs with at least a 50% reduction in arterial diameter, which correlates with a 75% narrowing of cross-sectional area
2D. Pain occurs at rest
3B. Can be caused by a major arterial dissection
4A. Cannot be performed when the carotid artery is completely occluded
5C. Is defined as a localized dilation of an artery to at least 1.5 times its normal diameter
CHAPTER 35
1C. Thermal ablation is an effective approach to the treatment of saphenous veins. The 2011 consensus opinion recommends thermal ablation to surgical or chemical ablation for GSVs. Selective treatment of incompetent perforating veins is not recommended in patients with simple varicose veins, though is an option for pathologic perforating veins. Vein absorption occurs over the course of months.
2D. Three months’ anticoagulation is similarly recommended in patients with (i) PE/proximal DVT of the leg provoked by a nonsurgical transient risk factor, (ii) in patients with PE/an isolated distal DVT of the leg provoked by surgery or by a nonsurgical transient risk factor. This is recommended over a longer or shorter duration of anticoagulation. Not all patients with DVT require anticoagulation for this period of time.
3D. Upper extremity venous duplex ultrasound. Upper extremity venous duplex ultrasound is both sensitive and reliable in the diagnosis of axillary-subclavian vein thrombosis. A chest x-ray is obtained to exclude the presence of cervical ribs which can contribute to the compression of the subclavian vein, but cannot be used solely in diagnosis. A CT venogram is not an appropriate initial evaluation modality. A CT angiogram will not properly image the subclavian vein.
4B. Up to 40% of presentations have associated acute DVT. Less than 10% and up to 40% of patients with superficial thrombophlebitis have been reported to have associated acute DVT. Generalized edema is present only if the deep veins are involved. Ambulation is encouraged along with NSAIDs, local heat, elevation, and support stockings. Most episodes of septic thrombophlebitis respond to conservative management and do not require operative treatment.
5C. Venous duplex scans aid in ruling out venous insufficiency and venous obstruction. The distribution of edema from lymphedema is centered around the ankle and is most pronounced on the dorsum of the foot. It often involves the toes, a characteristic not seen in venous stasis disease. Venous duplex scans are helpful in ruling out venous causes of edema, especially in patients with unilateral edema. Due to its minimal risk and ability to provide information on lymph transport and reflux, lymphoscintigraphy is the gold standard for evaluation of lymphatic function. Diuretics are not effective in the long-term treatment of lymphedema, though may be useful for acute exacerbations.
CHAPTER 36
1D. Is normally maintained at a stable level by displacement of CSF
2D. Trendelenburg position
3B. Is accompanied by initial hyporeflexia
4A. Occurs with axonal regeneration after wallerian degeneration at a rate of 1 mm per day
5C. Can cause symptoms related to the compression of the pituitary stalk causing increased prolactin levels
CHAPTER 37
1C. Medically manage the patient’s pain and nausea and arrange an urgent ophthalmology consult. Sudden onset of severe unilateral eye pain with decreased visual acuity, a dilated, unreactive pupil, hazy cornea, and elevated intraocular pressure is the classic presentation of acute angle-closure glaucoma. This is a vision threatening condition that must be managed urgently. It is necessary to treat the patient’s pain and nausea and lower the patient’s intraocular pressure with topical, oral, and IV medications; however, definitive treatment consists of performing a peripheral iridotomy.
2C. Obtain a maxillofacial CT scan and start on IV antibiotics. Acute onset of eyelid swelling with the additional signs of eyelid warmth and redness is highly suggestive of an infectious process. Double vision and limitation of extraocular movement on the affected side indicates that there is orbital involvement. Imaging is indicated to rule out abscess formation and IV antibiotics should be initiated. Oral antibiotics would be appropriate for a preseptal cellulitis; however, there are signs of orbital involvement in this case. Thyroid ophthalmopathy is a common cause of chronic, progressive unilateral proptosis and herpes zoster ophthalmicus can present with eyelid swelling and a vesicular rash.
3D. HSV keratitis classically presents with a dendritic corneal lesion. Ocular HSV infection is most commonly caused by HSV-1 and presents with eye irritation, reduced vision, and a dendritic corneal lesion on fluorescein staining. Herpes zoster virus (HZV) infection typically presents differently from HSV, often with vesicular skin lesions around the eye. If a vesicular lesion is found on the tip of the nose (Hutchinson sign) this is suggestive of intraocular involvement with HZV. Postherpetic neuralgia can be a painful sequela of HZV—not HSV.
4C. Nonexudative “dry” macular degeneration. VEGF targeting agents are used to treat a variety of ophthalmic conditions including diabetic macular edema, exudative macular degeneration, and other diseases in which neovascularization occurs such as neovascular glaucoma. VEGF-targeting agents are not used in nonexudative or “dry” macular degeneration.
5C. Instill tetracaine 0.5% and irrigate with ~2 liters of saline (or any other immediately available fluid) immediately. Ocular burns with the alkali ammonia are serious because of rapid penetration of ocular tissue and the significant tissue damage caused. Immediate steps should be taken to make the patient comfortable and irrigate the eye with large volumes of saline. Ophthalmology can be consulted while the patient is being irrigated and eventually, after the pH has normalized, topical dilating drops and antibiotic ointments may be instilled.
CHAPTER 38
1A. Prenephros
2A. Just outside the external ring
3D. Have a history of urinary tract infections
4A. Hyperoxaluria
5C. Transurethral prostatectomy
CHAPTER 39
1D. Luteal cyst
2D. Carcinoma occurs most frequently in women between the ages of 20 and 30 years
3B. Consists of radiation therapy and chemotherapy for advanced disease
4A. Are present in 20-30% of women of reproductive age
5D. A, B, and C
CHAPTER 40
1C. An open fracture is defined as an osseous disruption with a break in the overlying skin and soft tissues resulting in communication between the fracture and the external environment. Open fractures can be classified using the Gustillo and Anderson classification: Grade 1, clean skin opening less than 1.0 cm, Grade 2, traumatic wound greater than 1.0 cm but less than 10 cm in size, and Grade 3, extensive soft tissue injury requiring flap and/or vascular repair. Antibiotic treatment, tetanus prophylaxis and urgert irrigation and debridement in the operation is necessary. Fractures should be stabilized with internal or external fixation and/or splinting to minimize additional soft tissue injury.
2C. The clinical findings in spinal cord injury depend on the level, mechanism and severity of injury. Injuries are classified as complete or incomplete. A complete spinal cord injury refers to lack of motor or sensory function below the level of the lesion. Incomplete spinal cord injuries may demonstrate a variable pattern of sensory and motor preservation. The American Spinal Injury Association published a scale to classify the severity of SCI: ASIA A – complete, ASIA B- sensory incomplete, ASIA C- motor incomplete, ASIA D- motor incomplete, more than half muscles below lesion have > grade 3 strength, ASIA E – normal. Spinal shock is a spinal cord dysfunction due to physiologic disruption, resulting in hypotonia, areflexia and paralysis. Resolution usually occurs within 24 hours and the bulbocavernosis reflex is the first to come back.
3D. Pelvic fractures are among the most serious orthopaedic injuries, resulting in life-threatening hemorrhage, neurologic and genitourinary injury. Hemodynamically unstable patients have a mortality of 40-50%. Immediate care of the patient with a pelvic fracture must address the retroperitoneal hemorrhage, pelvic ring stability and injuries to the GU system. General resuscitation principles are applied and active bleeding from the pelvic can be controlled by wrapping a pelvic binder or sheet circumferentially around the pelvis to close down the pelvic volume.
4A. Traumatic knee dislocations can be limb-threatening because of disruption to the popliteal vasculature. If the knee remains dislocated at presentation, immediate reduction should be performed. Postreduction neurologic and vascular exam is critical. If there is any indication of abnormal arterial inflow (ABI < 0.9, diminished or absent pulses, delayed capillary refill) then arteriography is indication. If the limb is frankly ischemic, emergent vascular exploration is indicated.
5C. Supracondylar humerus fractures are among the most common injuries in children ages 4-8 years. The typical mechanism is a hyperextension injury after a fall onto an outstretched arm. If displaced, supracondylar fractures require urgent reduction and stabilization in the operating room. The anterior interosseous nerve is the most commonly injured with extension type fractures. Most nerve injuries represent neuropraxias that resolve with observation over the subsequent 3-6 months.
CHAPTER 41
1C. Full-thickness skin grafts are indicated for multiple reconstructive procedures. Long term, they have less of a contracture rate than split-thickness grafts. Due to the fact that it is full thickness, the number of skin appendages is actually increased. This allows for improved graft incorporation. This also makes them more resilient to trauma in both the immediate and long-term recovery. The aesthetics of a FTSG are generally better than a STSG due to the factors noted.
2B. A random pattern flap does not have a truly dedicated vascular pedicle to keep it alive. Therefore, due to its random pattern the length to width ratio is crucial for its survival. For example, if a 3-cm-long flap is required, the width should not be less than 2 cm, meaning a 1.5:1 ratio.
3B. The ischial pressure sore is a commonly encountered problem for the plastic surgeon. Adequate tissue coverage is mandatory, meaning skin graft and primary closure is not adequate. The rectus femoris would not be best suited to reach the ischium. The gracilis flap is a versatile flap that has been thoroughly described for pressure sore management.
4C. An AVM develops from arterial and venous misconnections. Over time this can lead to significant health consequences. Glut-1 is associated with hemangiomas. AVMs usually grow in proportion with the patient and do not usually express a rapid growth phase. In most cases, AVMs do not undergo involution on their own.
5E. the TRAM flap has been shown to be extremely versatile and provides the best aesthetic breast reconstruction for those patients with radiation therapy. When radiation therapy is involved, implants in general have been shown to cause more complications and less than desirable results.
CHAPTER 42
1D. The hand should be in the position of rest
2D. Zigzagged across lines of tension
3B. Can include camptodactyly
4A. Can be treated by local injections of corticosteroid
5C. Should usually incision of the transverse carpal ligament, which forms the roof of the tunnel
CHAPTER 43
1B. Bilious emesis is indicative of a proximal bowel obstruction. In a 2 month old who has been thriving, the abnormality that must be ruled out is a midgut volvulus. This typically occurs in the setting of malrotation with a narrow-based mesentery that is susceptible to clockwise rotation and strangulation of the mesenteric vessels. While Ultrasound has been used in the diagnosis of malrotation based on the relationship of the superior mesenteric vessels, it is not currently the test of choice with acute obstruction. CT scan can make the diagnosis, but it is unnecessarily costly and time consuming. Contrast enema can be indicative of malrotation, but will not confirm midgut volvulus. Esophagram will show neither malrotation nor midgut volvulus. Upper GI series is the current test of choice. The study classically shows a “corkscrew” sign with twisting of the small intestine near the ligament of Treitz, which may be displaced medially in the setting of malrotation.
2D. Thyroglossal duct remnants are the most common midline cervical congenital anomaly. Complete excision is indicated because of the risk of infection and the possibility of the development of papillary carcinoma later in life. Acute infection in thyroglossal tracts should be treated with antibiotics. Abscesses should be incised and drained. After complete subsidence of the inflammatory reaction (approximately 6 weeks), a thyroglossal cyst and its epithelial tract should be excised. The mid portion of the hyoid bone should be removed en bloc with the thyroglossal tract to the base of the tongue (Sistrunk procedure). Recurrences occur when the hyoid is not removed and when the cyst was previously infected or drained. Lymph nodes, dermoid cysts, and enlarged Delphian nodes containing tumor metastases may be confused with thyroglossal remnants in the midline of the neck. However unlike thyroglossal duct cysts, they do not move with swallowing.
3E. CDH is a physiological emergency, not a surgical emergency. Newborns should be stabilized and pulmonary hypertension managed prior to repair. ECMO is still used to manage severe respiratory failure and pulmonary hypertension, although its use is less common with advanced ventilator strategies and inhaled nitric oxide. CT scan can be used to differentiate CDH from cystic lung disease if there is a question, but the diaphragmatic defect cannot be visualized. Small defect are amenable to primary repair and mortality is determined by the degree of pulmonary hypoplasia.
4A. Tracheoesophageal fistula is associated with other congenital anomalies in 50% of cases and with the VACRERL association (vertebral, anorectal, cardiac, tracheoesophageal, renal, and limb anomalies) in 25% of cases. Workup of associated anomalies should be undertaken prior to surgery. Cerebral anomalies are not part of the association, thus screening head ultrasound is not necessary.
5B. N-myc amplification is a predictor of poor prognosis independent of stage. Young age, differentiation, and low LDH are all positive predictors. Stage IVs have favorable outcomes to older children with stage III and IV.
CHAPTER 44
1D. Cancer point prevalence describes the number of people with cancer at a given time
2D. Both A and C
3B. Can be described according to its absolute or relative benefit
4A. Have tumor size and tumor grade as the most important prognostic variables
5D. Should be excised with a 2 cm skin margin if greater than 2 mm thick
CHAPTER 45
1C. IFN-γ
2B. B-cell
3A. Two
4E. All of the above
5D. Metastatic colon cancer