Surgery Book MCQs - Final Exam

A 42-year-old woman with a history of alcohol abuse is admitted to the intensive care unit with active bleeding from esophageal varices. The medication most useful for decreasing the risk of rebleeding, with the least side effects, is A. octreotide B. proton pump inhibitor C. beta-blocker D. vasopressin E. nitroglycerin

Answer: A Although proton pump inhibitors are useful for bleeding ulcers and are usually given to patients with variceal bleeds, they do not decrease the bleeding. Beta-blockers and nitrates help prevent recurrent bleeds but are dangerous while the patient is bleeding. Vasopressin, used for years to help treat variceal bleeding, is a nonspecifi c vasoconstrictor and thus is risky. Octreotide can decrease rebleeding with few side effects.

A 62-year-old man is in the operating room undergoing an open left inguinal hernia repair. A large indirect sliding hernia is found, and during the dissection, the sigmoid colon is inadvertently injured. The colotomy is easily repaired with sutures. Which of the following hernia repairs should be used in this situation? A. Bassini repair B. Halsted repair C. Marcy repair D. Cooper's repair E. Lichtenstein repair

Answer: A An unexpected injury to the colon during an open hernia repair will change the wound classifi cation to a contaminated procedure and signifi cantly increase the risk of wound infection. Thus, mesh placement with a Lichtenstein repair should be avoided. Performing the more traditionalBassini repair that involves suturing Poupart's ligament to the conjoint tendon will be associated with a higher risk of hernia recurrence but avoids signifi cant wound complications. The Halsted repair is a largely historical procedure, which left the spermatic cord in the subcutaneous tissues. A Cooper repair (also known as a McVay repair) is more diffi cult to perform than a Bassini repair and would not offer additional benefi t in the repair of a sliding hernia, while the Marcy repair would be insuffi cient to offer any meaningful prevention of recurrence of a sliding hernia.

A 30-year-old man is in the hospital recovering from splenectomy for a ruptured spleen sustained in a motor vehicle collision. He has otherwise been healthy and was not taking medications prior to the injury. A temperature of 102°F is noted on the second postoperative day. Vital signs are BP 130/80 mm Hg, pulse 100/minute, and respirations 18/minute. His pain is moderately controlled with morphine using patient-controlled analgesia (PCA). Breath sounds are diminished at both bases, more so on the left. His abdomen is mildly distended, soft and tender near the incision. The incision appears to be healing without a problem. What is the most likely cause for his fever? A. Atelectasis and pulmonary infection B. Peritonitis C. Urinary tract infection D. Suppurative thrombophlebitis E. Cardiac contusion

Answer: A Early postoperative fever is usually the result of atelectasis and subsequent pulmonary infection (Table 8-6). In this scenario, because of the close proximity of the left hemidiaphragm to the spleen, an infi ltrate in the left lower lobe of the lung is a high probability. An adequately drained urinary tract in a young person seldom gives a high fever this early in the postoperative period. Although peritonitis from injury to a surrounding structure during the splenectomy (i.e., pancreas, stomach, or bowel) is a possibility, it is much less likely than a pulmonary source. Cardiac contusion does not elicit a febrile response

A 50-year-old man is started on IV heparin for a peripheral arterial thrombosis. Three days later, it is noted that his platelet count has dropped from 200 to 35. What is the next best step in management? A. Discontinue heparin and administer lepirudin B. Continue heparin and administer argatroban C. Discontinue heparin and administer aspirin D. Discontinue heparin and administer Coumadin E. Continue heparin and administer a platelet transfusion

Answer: A Heparin-induced thrombocytopenia (HIT) is a hypercoagulable state manifest by arterial and venous thromboses. HIT occurs as a result of antibody formation to heparin-platelet complexes and results in thrombocytopenia due to intravascular platelet activation and aggregation. There is no indication for platelet transfusion. It can occur due to administration of any type of heparin. Patients must be anticoagulated with an alternative agent such as argatroban, lepirudin, or danaparoid. In this setting, starting Coumadin without starting one of these alternative agents is contraindicated as the initiation of Coumadin therapy is associated with a transient hypercoagulable state.

A 65-year-old man is seen in the emergency department with a 5-day history of nausea and vomiting. He has been drinking only water for the last 2 days. His BP is 100/75 mm Hg with a heart rate of 105/minute. He has a distended abdomen with no bowel sounds but no signs of peritonitis. A diagnosis of a bowel obstruction is made after x-rays of the abdomen reveal distended loops of small bowel. Which of the following abnormalities would you expect to find in this patient? A. Na+—110 mEq/L, Cl−—90 mEq/L, K+—2.8 mEq/L, CO2—20 mEq/L B. Na+—150 mEq/L, Cl−—120mEq/L, K+—5.5 mEq/L, CO2—20 mEq/L C. Na+—140 mEq/L, Cl−—110 mEq/L, K+—4.0 mEq/L, CO2—26mEq/L D. Na+—120 mEq/L, Cl−—120 mEq/L, K+—5.5 mEq/L, CO2—18 mEq/L E. Na+—135 mEq/L, Cl−—105 mEq/L, K+—3.5 mEq/L, CO2—24 mEq/L

Answer: A In a patient with a bowel obstruction who begins vomiting, the initial acid-base abnormality would be a hypochloremic, hypokalemic metabolic alkalosis due to the loss of hydrogen ion, chloride, and potassium from the stomach. The bowel will continue to secrete fl uid into the small intestine, which will initially lead to hypovolemia that is compounded by the loss of gastric fl uid. This results in an increase in aldosterone, which will result in increased reabsorption of sodium and chloride from the kidney, but since the vomiting results in a loss of chloride, eventually a reduction in chloride in the renal tubule will result in absorption of bicarbonate with the sodium. The resulting alkalosis may be associated with a mild respiratory acidosis to compensate for the metabolic acidosis. As the fl uid sequestration in the small intestine increases, hypovolemia increases, which increases ADH and stimulates thirst. The kidneys reabsorb more water and sodium and the patient tries to drink but in this case only tolerates water. This results in an increase in water in relation to sodium in the extracellular fl uid (even though both are reduced compared to the normal state) and a hyponatremia occurs. Now the patient has a hyponatremic, hypokalemic, hypochloremic metabolic acidosis, which is compensated partly by a respiratory acidosis. As the hypovolemia progresses due to the sequestration of fl uid in the intestine and perhaps into the peritoneal cavity, the patient may develop a stage 2 shock state that results in a mild cellular acidosis, which eventually causes a metabolic acidemia superimposed on the metabolic alkalemia. Hence, the fi nal presenting electrolyte and acid-base abnormality seen on the electrolytes in this patient is a hyponatremic, hypokalemic, hypochloremic metabolic acidemia. The fi rst priority in the treatment of this condition is to correct the hypovolemia, in this case with normal saline since there is also a chloride defi cit, and add potassium to the fl uids since the patient has a profound potassium defi cit that may be slightly masked by a lower than normal pH. (See relation between acidosis and potassium in text.) Since the patient is stable without signs of peritonitis, there is time to correct the fl uid and electrolyte disorders before taking the patient to surgery. Failure to correct before surgery could result in multiple complications including a more profound hypotension and arrhythmias due to the low potassium. In general, correction of vascular volume takes precedence followed by correction of acid-base and potassium abnormalities and fi nally correction of any other fluid and electrolyte problems.

A 72-year-old man comes to clinic because his wife noticed that his eyes are yellow. Recently he has found that his urine is dark and the stool light in color. He has recently had a diminished appetite, but otherwise feeling well without other complaints. His past medical history is unremarkable. He smoked cigarettes for 30 years, but quit 15 years ago. He is afebrile. Vital signs are normal. He is deeply jaundiced. There is a nontender smooth globular mass consistent with an enlarged gallbladder in the right upper quadrant of his abdomen. The rest of his examination is normal. Which of the following is the most likely diagnosis in this patient? A. Pancreatic cancer B. Choledocholithiasis C. Choledochal cyst D. Biliary stricture E. Gallstones

Answer: A In order for the patient to present with jaundice and acholic stools, a bile duct obstruction must be present. Gallstones alone do not cause a bile duct obstruction. The other diagnoses may be associated with obstructed jaundice. Given the patient's age and the presentation, it is most likely that this patient has a pancreaticobiliary malignancy.

A 41-year-old woman presents to the emergency department with 18 hours of nausea, right upper quadrant abdominal pain, and fever. She ate a heavy meal the night before and has never experienced similar symptoms. Laboratory evaluation reveals an elevated white blood cell count, normal bilirubin, and slightly elevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The most appropriate imaging study to determine the etiology of her symptoms is a(n) A. plain abdominal radiograph. B. ultrasonography. C. endoscopic retrograde cholangiopancreatography (ERCP). D. contrast CT scan. E. HIDA scan.

Answer: B The patient likely presents with acute cholecystitis. The most sensitive and least invasive imaging study to document the signs of gallbladder wall thickening and pericholecystic fluid is an ultrasound.

A 65-year-old man is severely injured in a dump truck rollover accident. He has sustained bilateral femur fractures, a pelvic fracture, and a pulmonary contusion. A pulmonary artery catheter is placed in order to guide you in the optimization of his hemodynamic status and guide his resuscitation. Correction of which current value will have the most dramatic impact on his oxygen delivery? A. Measured cardiac output of 2 L/minute B. Serum hemoglobin of 12 mg/dL C. Arterial PO2 of 82 mm Hg D. Arterial oxygen saturation of 93% E. Pulmonary capillary occlusive pressure of 10 mm Hg

Answer: A Oxygen delivery is delineated by the relationship O2D = (CO × CaO2 × 10). 10 is a factor to convert mL O2/100 mL blood to mL O2/L blood. The key components of the relationship are CO (measured cardiac output, which in turn is defi ned by the relationship CO = HR × stroke volume) and arterial oxygen content (CaO2, defi ned as CaO2 = 1.39 × Hgb × SaO2 + (PaO2 × 0.0031) ). Of the answers listed, the most deranged from baseline is a CO of 2L/minute (average adult normal values are 4.5 L/minute for women and 5 L/minute for men), and, given the mathematical relationship of the O2D equation, it will have the greatest impact on this value when corrected. The values given for hemoglobin (B), arterial oxygen saturation (C), and pulmonary artery occlusive pressure (E) are all near or within normal values. Even relatively dramatic changes in arterial PO2 will have a minimal impact on O2D given the correction factor of 0.0031 as delineated in the CaO2 equation (answer C).

A 22-year-old man is in the emergency department after a highspeed motor vehicle collision. He complains of back pain. He is alert and oriented and is breathing normally. His oxygen saturation is normal and hemodynamically stable. There are ecchymoses on the left chest. Chest x-ray shows fractures of the left fi rst and second ribs. The aortic knob is not clearly visible, and the mediastinum measures 10 cm. Further evaluation should include which of the following? A. Contrast-enhanced chest CT B. Repeat chest x-ray C. Diagnostic thoracoscopy D. Pericardial window E. Diagnostic mediastinoscopy

Answer: A The high-speed deceleration mechanism and chest x-ray fi ndings are highly concerning for blunt aortic injury (BAI), which is most effi ciently diagnosed by contrast-enhanced chest CT. Repeat chest x-ray would likely reveal the same fi ndings but would not establish the diagnosis. Thoracoscopy is useful for evaluating the pleural space, lungs, and diaphragm, but not the aorta and great vessels. Pericardial window may be utilized to diagnose hemopericardium in suspected penetrating cardiac trauma, but not aortic injury. Mediastinoscopy is used for evaluating lymph node status in lung cancer staging but has no role in trauma. (Taken from Thoracic Injury: Potentially Severe Injuries Detected During Secondary Survey).

A 50-year-old woman has severe gallstone pancreatitis. She is receiving IV fluid and is receiving nothing by mouth in an effort to slow pancreatic secretion to decrease the amount of active pancreatic enzyme leaking into the disrupted glandular tissue. Which of the following enzymes is produced by the pancreas and secreted in its active form? A. Amylase B. Trypsin C. Chymotrypsin D. Cholecystokinin E. Gastrin

Answer: A The pancreas secretes a variety of digestive enzymes including amylases, lipases, and proteases. The majority of enzymes including trypsin and chymotrypsin are secreted in their inactive form (trypsinogen and chymotrypsinogen). Amylase is secreted in its active form. Cholecystokinin (CCK) is secreted by the duodenum and leads to the secretion of several pancreatic enzymes, while gastrin is a hormone primarily produced in the antrum. (Taken from Exocrine).

A 24-year-old woman is seen in clinic with anal pain. Examination shows a fissure in the anterior midline of the anal canal. Digital rectal exam cannot be performed due to pain. The next step in management should be A. sitz baths, bulking agent, and reassurance. B. intramuscular penicillin and oral tetracycline for sexually transmitted disease. C. evaluation for Crohn's disease. D. evaluation for leukemia. E. biopsy to rule out neoplasm.

Answer: A The presentation is classic for traumatic anal fissure. Fissures off the midline generally prompt evaluation for other etiologies.

A 25-year-old otherwise healthy woman is found to have a serum calcium of 10.9 mg/dL (normal 8.2 to 10.2 mg/dL) during a wellwoman preventive medicine visit. A parathyroid hormone (PTH) level returns 75 pg/mL (normal 13 to 65 pg/mL). She is asymptomatic. She takes no chronic medications. Family history discloses that her mother has hypercalcemia that has never required medication or operation. Physical examination is normal. The patient is most likely to have which of the following laboratory findings? A. Low calcium:creatinine clearance ratio B. Decreased serum vitamin D level C. Elevated serum PTHrP level D. Hypomagnesemia E. Hyperphosphatemia

Answer: A This asymptomatic patient with mild elevations of calcium and intact PTH levels and a family history of benign hypercalcemia most likely has FHH, familial hypercalcemic hypocalciuria. The diagnosis can be confi rmed by a 24-hour urine collection for calcium and creatinine, which should show calcium <100 mg/24 hours and a calcium:creatinine ratio <0.05. FHH does not affect vitamin D, magnesium, or phosphorus levels in the serum. FHH is not associated with production of parathyroid hormone-related protein. (Parathyroid/Secondary and Tertiary Hyperparathyroidism/Clinical Presentation and Evaluation)

A 28-year-old man is undergoing an operation for right inguinal hernia. The anesthesiologist notices that his end-tidal CO2 value rises abruptly, and the patient's jaw is stiff. The patient's temperature is 41°C, his heart rate is 130 beats/minute, and his blood pressure (BP) is 130/75 mm Hg. Which of the following abnormalities would be expected if a sample of his blood were tested at this point in the operation? A. Hyperkalemia B. Hypocalcemia C. Alkalosis D. Anemia E. Hypoalbuminemia

Answer: A This is a classic description of malignant hyperthermia. The typical electrolyte picture is that of rhabdomyolysis, with hyperkalemia, hypercalcemia, and acidosis. Malignant hyperthermia is not known to affect red cell mass or albumin levels. The patient should be given 100% oxygen, the operation should be stopped and the wound closed, and dantrolene should be administered.

A 35-year-old woman is seen in clinic because of weight gain and abnormal hair growth. She has gained 15 kg in 6 months, most notably in her torso. She denies increased appetite and has not changed her daily activity patterns. She has been emotionally labile and her previously regular menses have become irregular (periods are shorter or missed altogether). On examination, she has truncal obesity and hirsutism. The most likely primary cause of her symptoms is due to hyperfunction of which one of the following? A. Pituitary basophils B. Pulmonary enterochromaffin (Kulchitsky) cells C. Adrenal medullary cells D. Adrenal cortical cells E. Ovarian epithelial cells

Answer: A This patient has symptoms and signs of hypercortisolism (Cushing's syndrome). The most common cause of Cushing's syndrome in adults is an adrenocorticotropic hormone (ACTH)-secreting tumor of the pituitary basophils (Cushing's disease). Women in the third and fourth decades of life are the typical patients. Cushing's disease accounts for 70% of cases of Cushing's syndrome. Bronchial carcinoid tumors (arising from Kulchitsky cells) are a source of ectopic ACTH production. Ectopic ACTH syndrome causes about 15% of Cushing's syndrome in adults. The adrenal medulla does not produce glucocorticoids; tumors of the medulla are pheochromocytomas and produce excess catecholamines. A tumor of ovarian epithelial cells could lead to menstrual irregularities through excess sex steroid production but would not produce hypercortisolism. (Adrenal Glands/Disease States/Hyperadrenocorticism/Clinical Presentation/Diagnosis)

A 66-year-old man presented to the clinic with painless jaundice. Further evaluation with CT imaging and endoscopic ultrasonography (EUS) showed a small resectable tumor in the head of the pancreas and no evidence of metastatic disease. EUS-guided biopsy confirmed the diagnosis of pancreatic adenocarcinoma. Pancreaticoduodenectomy is planned. Which of the following statements regarding the role of adjuvant or neoadjuvant therapy for this patient is true? A. Adjuvant and neoadjuvant strategies can include radiation and/ or chemotherapy. B. There is no role for chemotherapy in the adjuvant or neoadjuvant setting. C. Neoadjuvant strategies are the standard of care for patients with pancreatic cancer. D. The use of neoadjuvant and adjuvant strategies is usually not indicated due to the low recurrence rates in patients with resected disease. E. Neoadjuvant therapy is given postoperatively.

Answer: A Unfortunately, even after successful surgical resection, the majority of patients with pancreatic cancer will develop recurrence of their disease— both locally and systemically. Due to the high recurrence rates, efforts aimed at developing adjuvant and neoadjuvant strategies have been pursued. Treatment can consist of either chemotherapy alone or with radiation. Treatment can be given preoperatively (neoadjuvant) or postoperatively (adjuvant). Although there are several theoretical advantages of neoadjuvant strategies with promising results, no randomized comparisons have been done versus adjuvant therapy. (Taken from Pancreatic Neoplasms, Adjuvant and Neoadjuvant Treatment for Pancreatic Cancer)

A 40-year-old woman is admitted with a 3-day history of diarrhea. She has a history of chronic renal insufficiency due to diabetic nephropathy. She is mildly acidotic. Serum potassium is 6.8 mEq/L. An ECG shows peaked T waves. Which of the following is the most appropriate initial treatment of the hyperkalemia? A. Subcutaneous administration of 10 units of insulin plus 25 g of glucose over 5 minutes B. Administration of a bicarbonate infusion or by injecting 45 mEq sodium bicarbonate intravenously over 5 minutes C. Intravenous administration of sodium polystyrene sulfonate, a cation-exchange resin, to bind extracellular potassium D. Transferring the patient to a center with hemodialysis and peritoneal dialysis capability E. Rapid intravenous infusion of 50 mL of 10% calcium gluconate under continuous ECG monitoring

Answer: A Hyperkalemia <6 mEq/L or hyperkalemia without ECG abnormalities usually needs minimal intervention other than stopping any potassium infusion, deciding if this increase in potassium is due to a signifi cant metabolic acidosis (since the potassium will increase at least 0.3 mEq/L for every 0.1 decrease in pH), checking to make sure the increased potassium was due to hemolysis of the blood sample, and monitoring the cardiac rhythm. If the patient has ECG evidence of peaked T waves, then prompt administration of 25 g of glucose plus 10 units of insulin is recommended followed by hemodialysis if necessary. If the T waves are higher than the R wave or if there is widening of the QRS complex and a decrease in the P-wave amplitude, immediate treatment is indicated with either infusion of 10 mL of 10% calcium chloride over 10 minutes or 10 mL of calcium gluconate over 3 to 5 minutes. Calcium chloride freely dissociates upon infusion resulting in 13 mEq of free calcium, whereas calcium carbonate results in only 4 mEq of free calcium. The remainder of the calcium is released as the carbonate is metabolized. Intravenous infusion of 50 mEq or more of sodium bicarbonate over 20 minutes may also be used. The amount of bicarbonate infused is proportional to the degree of acidosis but is usually not used unless the pH is <7.20. Rapid increase in potassium such as occurs with sudden renal failure or rhabdomyolysis may be lethal if not diagnosed and treated quickly.

A 52-year-old man with sigmoid colon adenocarcinoma is being evaluated for surgery. Preoperative workup reveals two liver mets. One met encases the right hepatic vein, and the other is in segment 4. There is no evidence of intrinsic liver disease and he is fit for surgery. From an anatomical prospective, which of the following surgical recommendations is most appropriate regarding his liver findings? A. No appropriate surgical option due to burden of disease B. Right trisectionectomy C. Right posterior sectionectomy and resection of segment 4 D. Right anterior sectionectomy and resection of segment 4 E. Right hepatectomy and adjunct treatments for segment 4

Answer: B A. Incorrect. Resection of all disease is achievable via a right trisectionectomy. If further concern regarding the function of the remnant liver exists, the surgeon may choose to employ techniques that hypertrophy the remnant liver (portal vein embolization or two-stage surgery). B. Correct. It will result in complete surgical removal of liver disease (see answer for "A"). C. Incorrect. The right hepatic vein is encased, thus making a right posterior sectionectomy oncologically unsound. D. Incorrect. The right hepatic vein is encased, thus making a right anterior sectionectomy oncologically unsound. E. Incorrect. Inappropriate treatment since segment 4 met is resectable.

A 60-year-old woman with chronic hepatitis C is brought to an acute care clinic by her family because of increasing confusion. Physical examination identifies jaundice, spider angiomata, and splenomegaly. Neurologic examination shows the patient to be lethargic; asterixis is present. Which of the following pharmacologic agents is most appropriate for treatment of this condition? A. Spironolactone B. Lactulose C. Somatostatin D. Ammonia E. Midodrine

Answer: B A. Incorrect. Spironolactone is a potassium-sparing diuretic used in patients with chronic liver disease and fluid retention (peripheral edema and ascites). B. Correct. Lactulose is a nonabsorbable disaccharide that acts to increase stool transit and convert ammonia to a nonabsorbable ammonium (NH4+). The goal of administration is for patients to have three to five soft stools per day. C. Incorrect. Somatostatin is a GI peptide that regulates endocrine function. It can be used to decrease mesenteric blood flow in patients with portal hypertensive bleeding. D. Incorrect. Increased levels of ammonia are associated with the development of hepatic encephalopathy, although it is unclear whether ammonia or an associated middle molecule is responsible for the alterations observed in mental status. E. Incorrect. Midodrine is a vasoactive antihypotensive oral peptide used in patients with symptomatic orthostatic hypotension.

A 25-year-old man is seen in the emergency department because of a painful swollen forearm. Two days ago, he sustained a small laceration to his left forearm while clearing brush. It caused only minor discomfort until about 12 hours ago when the area around the laceration became more red and swollen. He has otherwise been healthy. He takes no medications. His temperature is 38°C. There is a 2-cm superfi cial laceration on the dorsum of his left forearm with 15-cm diameter surrounding erythema that is quite tender. The edges of the erythema were marked and 20 minutes later the erythema has extended another cm beyond the mark. The most likely causative organism is A. methicillin-resistant Staphylococcus aureus. B. β-Hemolytic Streptococcus A. C. Escherichia coli. D. Streptococcus faecalis. E. Candida albicans.

Answer: B Although cellulitis may be caused by any organism, the most likely early organism would be ß-hemolytic Streptococcus A. Methicillinresistant Staphylococcus aureus more commonly causes local infl ammation and pus formation. The other three species are rarely isolated from skin infections but more commonly are seen in infections involving the gastrointestinal tract

Two weeks following a severe motorcycle crash, a 25-year-old woman remains intubated in the surgical ICU. You are called to the bedside to evaluate a change in her condition. On evaluation, her vital signs include temperature of 39°C, heart rate of 110 beats/minute, respiratory rate of 22, blood pressure of 88/50, and arterial oxygen saturation of 96%. Her urine output has been 20 mL over the past 8 hours. On exam, she is in moderate distress and appears confused. She has crackles posteriorly in her left lung fields and her extremities are warm. A bronchoalveolar lavage is performed revealing Gram-negative rods. What is your diagnosis? A. Atelectasis B. Septic shock C. Systemic inflammatory response syndrome D. Allergic reaction to penicillin E. Pulmonary embolus

Answer: B Although infl ammation is a normal response to tissue injury, the patient in the above scenario is displaying evidence of a dysfunctional infl ammatory response. The derangements noted are too severe for atelectasis (answer A), which is associated with slight fever and normal blood pressure. Although allergic reactions (answer D) can be associated with cardiovascular collapse, there is no history of recent medication administration given. Pulmonary embolus (answer E) may present as tachycardia and hypotension but is typically also associated with hypoxia.To meet the definition of the systemic inflammatory response syndrome, or SIRS, a patient must have two or more of the following conditions: (1) temperature >38.5°C or <36°C; (2) heart rate >90 beats/minute; (3) respiratory rate >20 breaths/minute or PaCO2 < 32 Torr; and (4) total leukocyte count >12,000 cells/mm3 , <4000 cells/ mm3 , or >10% immature forms. Although the patient in the scenario meets these criteria (answer C), the additional presence of end-organ dysfunction (hypotension, oliguria) and infection (Gram-negative rods on bronchoalveolar lavage [BAL]) make the diagnosis of septic shock more appropriate (answer B).

A 53-year-old man sustains a severe traumatic brain injury after an assault. His GCS score is 6, and an intracranial pressure monitor is inserted. Vital signs are heart rate—92 beats/minute, blood pressure (BP)—152/88 mm Hg, mean arterial pressure—109 mm Hg, and respiratory rate—16/minute. His intracranial pressure is 32 mm Hg. The patient's cerebral perfusion pressure is A. 120 mm Hg. B. 77 mm Hg. C. 60 mm Hg. D. 56 mm Hg. E. 32 mm Hg.

Answer: B Cerebral perfusion pressure (CPP) is calculated by subtracting the intracranial pressure (ICP) from the mean arterial pressure (MAP). (Taken from Head Injury: Anatomy and Physiology).

A 55-year-old woman is scheduled for a craniotomy to remove a brain tumor. She has a history of hypertension and hypercholesterolemia, and she underwent coronary artery angioplasty with a stent placed 6 months ago. Current medications include enalapril, pravastatin, and clopidogrel. Which one of the following would most likely be prolonged? A. Activated partial thromboplastin time (APTT) B. Bleeding time C. Prothrombin time (PT) D. Thrombin time E. Activated clotting time (ACT)

Answer: B Clopidogrel is a platelet-inhibitor medication that is often used after the placement of intravascular stents to prevent thrombosis. Like aminopsalicylic acid (ASA), clopidogrel is nonreversible; therefore, it should be stopped 7 to 10 days before surgery if normal coagulation is required. Prolonged bleeding time is associated with platelet dysfunction. The APTT (intrinsic and common pathways), PT (extrinsic and common pathway), and thrombin time (formation of fi brin from fi brinogen) evaluate specifi c aspects of the coagulation cascade.

A 45-year-old woman is seen in clinic because of skin nodules on the upper portion of the breast and over the clavicle. One year ago, she underwent lumpectomy and sentinel node biopsy for Stage IIA invasive ductal carcinoma, ER+, PR−, and HER-2/neu-. She then received a full course of whole-breast radiation with a boost to the tumor bed. After four cycles of cytotoxic chemotherapy, she was started on tamoxifen by her oncologist. Physical exam shows several clusters of firm nodules in the skin over the clavicle and along the upper portion of the left breast. Biopsy of one of these nodules shows metastatic breast cancer. What is the best treatment now? A. An aromatase inhibitor B. Cytotoxic chemotherapy C. Immediate mastectomy D. Radiation treatment to the affected area E. Trastuzumab

Answer: B Cytotoxic chemotherapy should be started as soon as possible. An aromatase inhibitor is not indicated. The patient has already failed hormonal treatment, as her cancer has advanced while she was taking tamoxifen. This is not a single skin nodule but rather several clusters extending beyond the breast. Mastectomy is a local treatment and may be considered, including excision of the entire area of involved skin and possible skin graft, if she responds to systemic treatment (cytotoxic chemotherapy). The breast has already been radiated once and should not be radiated again. Trastuzumab is only effective in HER2/neu-positive breast cancers; it is a monoclonal antibody that binds selectively to the Her-2 protein, a regulator of cell growth. This patient is HER-2/neu negative. Section: Treatment for recurrent and metastatic breast cancer.

A 60-year-old woman is being evaluated for surgery to repair an abdominal aortic aneurysm under general anesthesia. She smoked a pack of cigarettes daily for 35 years, but quit 5 years ago when she had a myocardial infarction (MI) complicated by congestive heart failure. She still has occasional orthopnea. She also has hypercholesterolemia and hypertension. Which one of the following factors suggests the greatest risk for a cardiac complication following her surgery? A. History of cigarette smoking B. Congestive heart failure with orthopnea C. General anesthesia D. Hypertension E. Hypercholesterolemia

Answer: B General anesthesia does not itself increase risk of cardiac complications.The factors that do increase such risk include ischemic heart disease, congestive heart failure, chronic kidney disease, cerebrovascular disease, or high-risk operations such as major vascular surgery.

A 25-year-old man suffers burns to 40% total body surface area (TBSA) in an explosion at a natural gas drilling site. He requires emergent intubation and fl uid resuscitation. During his fi rst week of hospitalization, he undergoes a major operative procedure for excision and skin grafting. By the end of the third week in the hospital, his weight (which originally increased with resuscitation) has come back down, and he weighs 12 pounds less than before the injury. What is the most likely cause for his weight loss? A. Decreased nitrogen excretion and resulting catabolism B. Increased nitrogen excretion and resulting catabolism C. Protein malnutrition with respiratory muscle building D. Immune system building with increased risk of pneumonia and bacteremia E. Indirect calorimetry readings to support positive nitrogen balance

Answer: B In response to the increased metabolic demands of a major burn, skeletal muscle is broken down to provide an available energy substrate. This results in increased nitrogen excretion, and loss of lean body mass, which can exceed a half pound per day. Cardiac muscle and respiratory muscles are not immune from these effects, and as muscle wasting continues, both heart failure and respiratory failure can occur. Loss of as little as 15% lean body mass can lead to a fatal degree of inanition within a few weeks of injury. Section: Defi nitive Care of Burn Injuries. Subsection: Nutritional Support.

A 52-year-old man was admitted to the hospital with bilateral femur fractures and rib fractures following a motor vehicle crash. He developed a deep vein thrombosis involving the left femoral vein and was started on intravenous heparin 4 days after admission. His platelet count decreased and concern was raised for heparininduced thrombocytopenia. Which of the following would be the best alternative anticoagulant? A. Clopidogrel B. Argatroban C. Warfarin D. Enoxaparin E. Aspirin

Answer: B In this setting, any heparin product should be stopped immediately, including low molecular weight heparin, such as enoxaparin. Use of warfarin is appropriate in the long term but will not be effective immediately. Antiplatelet therapies, such as aspirin and clopidogrel, have no proven role as substitutes for anticoagulants. The best choice is argatroban, a direct thrombin inhibitor.

A 52-year-old man is in the clinic to discuss treatment of a newly diagnosed pancreatic cancer. He has no significant past medical history. He takes no medications. There is no evidence of metastatic disease, and the tumor is small and appears to be resectable by pancreaticoduodenectomy (Whipple procedure). Optimal treatment would also include adjuvant radiation therapy and chemotherapy. Informed consent for this patient is best defined as A. a form that can be used as a legal defense should a complication occur during the treatment of the patient's problem. B. a process in which the physician and patient discuss the risks and benefits of different approaches to the patient's problem. C. a process in which every possible complication of treatment is enumerated. D. a theoretical construct with little practical utility. E. a philosophical principle that applies to surgical procedures but not medication administration.

Answer: B Informed consent is a process in which the physician and patient discuss the risks and benefits of different approaches to the patient's problem. This includes discussion of the most likely outcomes of treatment (including the decision to observe rather than operate). Informed consent permeates most of the discussions physicians have with their patients, although the discussions may not be labeled as such. It applies to medication choices as much as to surgical decision making, although a separate consent form is generally not obtained each time a new medication is prescribed.

A patient is scheduled to undergo open abdominal aortic aneurysm repair. During preoperative testing, it is determined that his blood type is B negative. This means A. he has circulating antibodies to Rh antigens. B. he has circulating antibodies to A antigens. C. he has circulating antibodies to B antigens. D. he has no circulating antibodies to ABO antigens. E. his red blood cells have A antigens.

Answer: B Multiple blood cell antigens exist; however, the ABO and Rh antigens are most clinically relevant. A person with blood type B means his red cells have the B antigen. His plasma will have antibodies to the A antigen. In patients who are Rh negative, they will not have circulating antibodies to the Rh antigens unless they have been previously exposed (e.g., during pregnancy of an Rh-negative mother with an Rh-positive fetus). Hence, in this case, although he is Rh negative, he will not have circulating Rh antibodies.

A 20-year-old man comes to the emergency department with severe epigastric pain. He has a history of pancreatitis 8 months ago, but no cause was identified. He has otherwise been healthy. He does not smoke or drink alcohol. He takes no medications. His vital signs are temperature—38°C, blood pressure (BP)—130/80 mm Hg, pulse—110/minute, and respirations—18/minute. He has severe epigastric tenderness with guarding. There is no scleral icterus. An ultrasound does not show gallstones. The bile ducts are not dilated. Laboratory studies show: Lipase—20,000 units; Total bilirubin—0.9 mg/dL; Calcium—9/0 mg/dL. Which of the following additional findings is most likely to support the diagnosis of pancreas divisum? A. An absent duct of Santorini B. Separate dorsal and ventral ducts C. The majority of pancreatic secretions enter the duodenum via the duct of Wirsung. D. Separate common bile duct and pancreatic duct E. Dilatation of the pancreatic duct

Answer: B Pancreatic divisum generally encompasses a variety of anatomic abnormalities whereby the majority of the dorsal pancreas empties into the duodenum via the duct of Santorini and a portion of the pancreatic head and uncinate empty via the major papilla. The abnormalities can include an absent duct of Wirsung and separate dorsal and ventral ducts that do not fuse as well as a fi lamentous connection between the dorsal and ventral ducts. In the absence of divisum, that is, in the normal state, the dorsal and ventral ducts join and the majority of secretions enter the duodenum via the duct of Wirsung through the major papilla. The common bile duct is separate from the pancreatic duct until they merge at near the ampulla. (Taken from Embryology and Ductal Anatomy).

A 48-year-old woman is in the hospital because of nausea, vomiting, and abdominal pain. She has a history of multiple abdominal surgeries for small bowel obstruction. On admission, she was quite thin with temporal and thenar muscle wasting. Her albumin level was 1.7 g/dL. A nasogastric tube was inserted and she has been receiving TPN for 2 days. You are now called by her nurse because, in addition to nausea and abdominal pain, she's begun to feel short of breath and have tingling in her fingers. She suddenly goes into cardiac arrest. Laboratory values now show potassium—2.4 mEq/L, magnesium—1.3 mEq/L, phosphorus—1 mg/dL, and glucose—350 mg/dL. What nutritional complication may have resulted in this patient's condition? A. Marasmus B. Refeeding syndrome C. Overfeeding D. Underfeeding E. Kwashiorkor

Answer: B Refeeding syndrome occurs when chronically starved patients lose the ability to tolerate acute changes in volume or caloric load. This results in a constellation of fluid, micronutrient, electrolyte, and vitamin imbalances within the first hours to days following nutrient infusion. These patients are typically hypokalemic, hypophosphatemic, hypomagnesemic, and hyperglycemic. This may result in symptoms, including hemolytic anemia, respiratory distress, paresthesias, tetany, and cardiac arrhythmias including sudden cardiac death. (Complications of Initiating Nutritional Therapy)

A 45-year-old man with a 25-year history of hepatitis C and cirrhosis is found to have a small hepatocellular carcinoma of the right lobe of the liver. In order to assess his risk for surgical therapy, an estimate of liver dysfunction given by the model for end stage liver disease (MELD) score is needed. Which one of the following laboratory studies is needed to calculate a MELD score for this patient? A. Alkaline phosphatase B. Serum creatinine C. Serum ammonia D. Serum albumin E. Serum gamma glutamyl transpeptidase (γ GT)

Answer: B The MELD score formula is (0.957 × ln(Serum Creatinine) + 0.378 × ln(Serum Bilirubin) + 1.120 × ln(INR) + 0.643 ) × 10 (if hemodialysis, value for creatinine is automatically set to 4). Albumin is a component of the Childs-Pugh classification, but not the MELD score. Alkaline phosphatase is useful in determining biliary tract obstruction. Gamma GT is very sensitive for hepatobiliary disease and is best used to determine if an isolated elevation of alkaline phosphatase is due to liver rather than bone disease.

A 46-year-old man is in the intensive care unit following surgery for multiple gunshot wounds to the chest and abdomen sustained 2 days ago. He has bilateral chest tubes inserted for hemopneumothoraces. Damage control surgery including packing his liver and performing an ileostomy was done at that time. His urine output has decreased to 90 mL over the past 4 hours. His temperature is 38°C, blood pressure (BP) 110/85 mm Hg, and pulse 100/minute. What is the most likely cause for the drop in urine output? A. Congestive heart failure B. Hypovolemia C. Acute renal failure D. Diabetes insipidus E. Sepsis

Answer: B The most common cause for a drop in urine output after surgery is hypovolemia. This can be caused by inadequate fl uid replacement to correct the sequestration of fl uid into the site(s) of injury, continuing blood loss, and stimulation of various endocrine responses including an increase in aldosterone, which results in renal sodium retention and an increase in antidiuretic hormone (ADH), which result in reduced free water clearance in the kidney. Atrial natriuretic factor may be inhibited due to the reduction in atrial volume and distention. The patient has a narrow pulse pressure and increased heart rate consistent with a low stroke volume and perhaps reduced cardiac output. The latter could be due to a combination of an absolute hypovolemia and/or a relative hypovolemia if he is developing an abdominal compartment syndrome, which could also contribute to decreasing urine output. The patient is relatively young to have congestive heart failure. Acute renal failure would be possible but is unusual only 2 days after surgery. Diabetes insipidus would result in increased urine output. Sepsis or an infl ammatory response syndrome would result in an increase in heart rate and a wider pulse pressure due to the vasodilation that occurs as a result of the release of various cytokines. In this patient, treatment would begin by performing a detailed physical exam followed by increased fl uid infusion.

A 27-year-old man is sprayed with concentrated sulfuric acid while working in an oil refi nery, sustaining burns to his face, hands, and forearms. He is brought immediately to the emergency room. On initial exam, he is awake and in pain. His clothes are soaked with acid. In addition to providing appropriate protection for all health care workers, the fi rst step in management should be to A. debride his burns and complete a Lund and Browder chart. B. immediately place the patient in a decontamination shower. C. perform a secondary survey. D. begin fluid resuscitation. E. contact the local burn center for referral.

Answer: B The patient illustrates the danger that health care workers face when dealing with hazardous material spills. Unwary physicians and nurses who attempt to help this man could suffer serious burns from the acid on his clothing, which is continuing to burn the patient as well. This chemical must be neutralized before a primary survey can be conducted safely. All of the other answers are appropriate steps in treatment but should not be performed until after the patient is decontaminated. Section: Special Problems in Burn Care. Subsection: Chemical and Electrical Burns.

A 42-year-old woman comes to the emergency room with epigastric pain radiating to right upper quadrant. She underwent a laparoscopic adjustable gastric band 6 months ago. She has lost approximately 80 lbs over the 6 months. She is afebrile with stable vital signs. A right upper quadrant ultrasound is shown below. Which of the following medications would have been most effective in preventing this complication? A. Sucralfate B. Ursodeoxycholic acid C. Cholestyramine D. Calcium citrate E. Omeprazole

Answer: B This patient has developed symptomatic cholelithiasis following rapid weight loss after a bariatric procedure. The ultrasound shows several echogenic stones within the gallbladder. Without pharmacotherapy, the risk of gallstone formation during this period approaches 30%. The prophylactic use of ursodeoxycholic acid decreases the risk of gallstone formation to approximately 2%. Sucralfate is used to promote healing of anastomotic ulcers. Cholestyramine is used in the treatment of alkaline reflux gastritis to bind bile salts. Calcium citrate is given to bariatric patients to prevent calcium defi ciency and subsequent osteoporosis. Omeprazole is a proton pump inhibitor used in the treatment of anastomotic ulcers. (Surgical Treatment of Obesity/Complications of Bariatric Operations/Late Complications)

A 6-year-old girl was burned in a house fi re and unable to escape. She was found unconscious by fi refi ghters, who intubated her at the scene. On arrival in the burn center, she is found to have carbonaceous sputum, elevated carboxyhemoglobin levels, and burns to 30% TBSA. You should inform her parents that inhalation injury signifi cantly increases the mortality rate of patients with major burns mostly due to A. increased metabolic rate and protein-calorie malnutrition. B. persistent pulmonary infection and eventual development of multiple organ failure. C. hypoxia. D. airway obstruction. E. increased fluid requirements for resuscitation.

Answer: B Though inhalation injury can produce immediate death from carbon monoxide poisoning and hypoxia, patients who survive the initial event should survive this problem. Similarly, airway obstruction is usually a treatable problem with limited time course. Pneumonia is the most worrisome complication of smoke inhalation, because it is often persistent/recurrent, and diffi cult to treat. Persistent infection—including pneumonia—often leads to development of the multiple organ failure syndrome, which is usually fatal. Section: Pathophysiology of Burn Injury. Subsection: Pathophysiology of Inhalation Injury.

A 35-year-old woman comes to clinic because of a 2-month history of thickening in the upper outer quadrant of her left breast. The patient's mother had breast cancer at age 48. Physical examination shows a slight retraction of the skin in the upper outer quadrant when the patient is upright. The breast tissue in that quadrant is rather firm, with the impression of a poorly demarcated thickening. A mammogram also shows dense tissue with no distinct mass or suspicious microcalcifications. What is the next step in the evaluation? A. Reexamine in 3 months B. Ultrasound of the palpable area C. Excisional biopsy D. Stereotactic biopsy E. Give a 2-week course of the antibiotic, clindamycin

Answer: B Ultrasound is an adjunct to mammography that is useful to characterize palpable masses; ultrasound of the palpable area may give the most useful information at this time. The radiographic finding is discordant with suspicious clinical presentation; further diagnostic workup is required. Excisional biopsy without prior attempted needle biopsy can lead to suboptimal management of a breast cancer. Stereotactic biopsy can only be performed on a lesion demonstrated by mammography. A breast abscess is exquisitely tender and demonstrable by ultrasonography. Section: Evaluation of the patient with breast mass.

A 32-year-old man is seen in the emergency department 45 minutes after a motor vehicle collision. His only injury is a long linear laceration beginning on the left temporal forehead at the hairline and extending posteriorly for 10 cm. The edges are still bleeding briskly and the EMTs described a large amount of blood at the scene. He did not lose consciousness. His last tetanus booster was 4 years ago. Which of the following is required for tetanus prophylaxis in this patient? A. Tetanus immune globulin only B. Nothing further at this time C. Tetanus toxoid only D. Tetanus immune globulin followed by a single tetanus toxoid booster E. Tetanus immune globulin followed by three tetanus boosters

Answer: B Wounds prone to the development of tetanus include those with extensive contamination with soil, deep puncture wounds from metal objects, exposure injury complicated with frostbite, and wounds >6 hours from time of injury (Table 8-8.). Linear lacerations in general are not prone to tetanus. The extent of blood loss does not affect the need for tetanus booster administration. The patient last received tetanus toxoid <5 years ago, so nothing further is required.

A 46-year-old man presents to the emergency department with hematemesis. There have been no prior episodes. He admits to drinking a pint of hard liquor daily for more than 10 years. Upper gastrointestinal endoscopy is performed and shows bleeding esophageal varices. Which of the following is the best management for this patient's bleeding? A. Emergency surgical portosystemic shunt B. Luminal tamponade C. Endoscopic rubber band ligation D. Transjugular intrahepatic portacaval shunt (TIPS) E. Peritoneovenous shunt

Answer: C A. Incorrect. Emergency surgical portosystemic shunt procedures are associated with a very high morbidity and mortality rate, especially liver failure. In addition, other measures are usually able to control bleeding so that invasive procedures can be performed on a semielective basis under optimized conditions. B. Incorrect. Luminal tamponade with a Sengstaken-Blakemore (or similar device) tube is usually employed as a last ditch effort in patients who have failed medical management and endoscopic therapy. C. Correct. Endoscopic therapy with rubber band ligation has become the procedure of choice in patients with bleeding esophageal varices and should be performed as soon as the diagnosis is made and the patient initially stabilized. D. Incorrect. Transjugular intrahepatic portacaval shunt (TIPS) is associated with a high rate of liver failure when performed as an emergency procedure in unstable patients. For this reason, TIPS should be performed on an elective basis in patients with well-compensated liver disease. E. Incorrect. Peritoneovenous shunt placement is occasionally used for patients with intractable ascites but will have no effect on portal hypertension or variceal bleeding.

A 65-year-old woman with severe symptomatic anemia secondary to chronic renal disease is being transfused with packed red blood cells. A couple of minutes into the transfusion, she complains of back pain, chest pain, and shortness of breath. The most likely diagnosis is A. transfusion-related acute lung injury (TRALI). B. delayed hemolytic transfusion reaction. C. acute hemolytic transfusion reaction. D. transfusion-related volume overload. E. transfusion-related hyperkalemia.

Answer: C Acute hemolytic transfusion reactions are usually caused by clerical error resulting in the administration of ABO mismatched blood. Host antibodies bind to antigens in donor red blood cells resulting in hemolysis. This may result in renal failure and shock. Patients complain of shortness of breath, chest pain, and back pain. The most appropriate course of action is to stop the transfusion, provide supportive therapy, and have the blood rechecked. TRALI usually occurs after completion of transfusions. Volume overload and hyperkalemia are unlikely only minutes into a transfusion.

A 38-year-old man has undergone four operations for Crohn's disease in the last 10 years and recently underwent the last of these for treatment of recurrent disease proximal to a prior ileocolic anastomosis. Which of the following agents is most useful for managing acute exacerbations rather than helping to maintain him in remission from active disease? A. Azathioprine B. Infliximab C. Prednisone D. Methotrexate E. 6-mercaptopurine

Answer: C All other agents have been successfully used in remission maintenance strategies.

A 48-year-old man is being evaluated in the emergency department with fevers, chills, and abdominal pain for the past 24 hours. He has a history of hepatitis C infection following a blood transfusion 14 years ago for a large scalp laceration and orthopedic injuries sustained in a motor vehicle collision. He has not been to a physician for 5 years. He does not smoke or drink alcohol. He takes no medications. His temperature is 39°C and vital signs are: blood pressure (BP) 90/50 mm Hg, pulse 110/minute, and respirations 26/minute. A CT scan shows a single stone in the gallbladder that does not appear to be obstructing. The bile ducts are normal caliber and the gallbladder wall is not thickened. There is a moderate amount of fluid, mild small bowel distention, and stranding around the sigmoid colon as well as a small amount of free intraperitoneal gas around the liver. An aspirate of the peritoneal fluid shows leukocytes and mixed Gram positives and negatives on Gram stain. Laboratory values show a WBC of 19,000/mm3, total bilirubin 1.2 mg/dL, and alkaline phosphatase 40 U/L. In addition to fluid resuscitation and broad-spectrum antibiotics, what is the best step in management? A. Laparoscopic cholecystectomy B. Long-term antibiotics only C. Laparotomy D. Magnetic resonance cholangiopancreatography (MRCP) E. Endoscopic retrograde cholangiopancreatography (ERCP)

Answer: C This patient has secondary peritonitis. This usually involves perforation of a hollow viscus and thus involves contamination of the peritoneal cavity with multiple organisms. Gram stain and culture of the peritoneal fl uid usually shows a single organism in patients with primary peritonitis and this can be treated with antibiotics without surgical intervention. In this scenario, the CT scan shows stranding around the sigmoid and fl uid and evidence of free air suggestive of a diverticulitis with fecal peritonitis. Patients with underlying liver disease are prone to gallstones and are a common fi nding. There is no evidence of common bile duct obstruction that warrants further investigation since the alkaline phosphatase is normal.

A 34-year-old woman is being evaluated for epigastric pain and is found to have an ulcer in the anterior duodenal bulb on upper endoscopy. Rapid urease testing of a mucosal biopsy of the antrum of the stomach is positive. In addition to omeprazole, appropriate therapy at this time would include a 2-week course of omeprazole, metronidazole, and A. amoxicillin and metronidazole. B. tetracycline and cephalexin. C. clarithromycin and amoxicillin. D. cephalexin and metronidazole. E. bismuth and cephalexin.

Answer: C All patients presenting with duodenal ulceration should undergo testing for the presence of Helicobacter pylori infection. The rapid urease test can be performed on antral stomach biopsies and is indicative of infection if positive. If H. pylori infection is present, it should be eradicated. First-line therapy includes acid suppression with clarithromycin and amoxicillin or clarithromycin and metronidazole for a minimum of 7 days. Traditional quadruple therapy is a second-line treatment and consists of acid suppression with bismuth, metronidazole, and tetracycline for a minimum of 7 days. (Benign Duodenal Ulcer/Uncomplicated Duodenal Ulcer Disease)

A 22-year-old man is transported emergently to the hospital after sustaining a stab wound to the left chest. On initial survey, his airway is patent and he is breathing spontaneously, but he appears to be in shock. Which of the following findings best supports your working diagnosis of pericardial tamponade? A. Central venous pressure of 8 mm Hg B. Crisp S1S2 on cardiac auscultation C. Paradoxical pulse of 18 mm Hg D. Left atrial distention E. Increased QRS voltage on ECG

Answer: C As the disease process progresses, pericardial tamponade results in decreased venous return, with resultant decreased stroke volume, hypoperfusion, and shock. Clinical evidence of tamponade includes an increased paradoxical pulse (>15 mm Hg; answer C). Other signs include elevated central venous pressure (rather than normal, answer A), muffl ed heart sounds (rather than crisp S1S2, answer B), left atrial collapse (rather than distension, answer D), and decreased QRS voltage on ECG (answer E).

A 43-year-old woman is being considered for antireflux surgery. She has a long history of reflux symptoms that are now only partially controlled with lifestyle changes and a proton pump inhibitor. Upper endoscopy showed a small hiatal hernia and a short segment of intestinal metaplasia, but no evidence of dysplasia. She wants to know the possible advantage of the Toupet (partial) fundoplication as compared to the Nissen (full) fundoplication. The theoretical advantage for the Toupet fundoplication procedure is A. decreased morbidity and mortality when compared to the Nissen procedure. B. better long-term relief from gastroesophageal reflux disease (GERD). C. decreased postoperative symptoms of dysphagia and gas bloat. D. prevention of malignant progression of Barrett's disease. E. avoidance of a thoracotomy incision.

Answer: C Because the Toupet procedure is a partial fundoplication, there is less risk for developing dysphagia or from having diffi culty burping as compared to a full encircling fundoplication. Both the Toupet and Nissen procedures can be performed laparoscopically with minimal morbidity and mortality. Because the Nissen is a full fundoplication, many proponents argue that it provides better protection from recurrent refl ux. No antirefl ux procedure has been conclusively shown to prevent or reverse Barrett's disease, and continued periodic endoscopic monitoring is recommended. Both the Toupet and Nissen procedures are usually performed through an abdominal incision.

A 42-year-old woman is seen in the infectious disease clinic because of a small laceration. She is a surgeon and was assisting a surgical resident with a colon resection when she was accidentally cut with a scalpel blade during the procedure. She has received all required immunizations. Antibodies against which virus could be measured in order to assess the effectiveness of the only vaccine to prevent infection potentially transmitted from the patient to the surgeon during the operative procedure? A. Human immunodeficiency virus B. Hepatitis C C. Hepatitis B D. Cytomegalovirus E. Tuberculosis

Answer: C HIV, hepatitis B, hepatitis C, and cytomegalovirus are transmitted by body fl uids and blood; therefore, they pose an occupational risk to the surgeon. There is currently a highly effective vaccine for the prevention of hepatitis B in the host. No such vaccine is available for the other viral infections. Tuberculosis is not a virus but also poses a risk to health care workers.

A 35-year-old woman comes to clinic because of right breast pain for the past 3 months. The pain is cyclical in nature. Her mother and two maternal aunts were all diagnosed with breast cancer in their 30s. There are no abnormal findings on exam and a recent diagnostic mammogram and ultrasound are normal. Which of the following would be the most appropriate option for management? A. Prophylactic right breast mastectomy B. Chemoprevention with an oral contraceptive C. High-risk screening and genetic counseling D. Reassurance and routine observation E. Prophylactic hysterectomy

Answer: C High-risk screening and genetic counseling is the best option for this patient. Prophylactic mastectomy is one of several options for the management of women at high risk for developing breast cancer and has been associated with a 90% reduction in relative risk. However, both breasts are potentially at risk; therefore, a unilateral prophylactic mastectomy would not be most appropriate for achieving this risk reduction. Evidence from clinical trials has demonstrated successful chemoprevention of breast cancer in high-risk women treated with tamoxifen or raloxifene. These agents are associated with an approximately 50% reduced risk of breast cancer. Although oral contraceptive use has not been defi nitely linked to increased breast cancer risk, there have been no clinical trials demonstrating its effectiveness in breast cancer prevention. The patient described has a concerning family history of breast cancer in that she has two fi rst-degree relatives diagnosed with breast cancer at a young (presumably premenopausal) age. The patient's family history suggests that she may carry an inherited genetic mutation, such as BRCA1/2, which increases her lifetime risk of developing breast and ovarian cancer. High-risk screening and further genetic assessment would be appropriate management strategies rather than reassurance and routine observation. There are several risk-reduction strategies including high-risk screening, lifestyle modifi cation, genetic testing, chemoprevention, prophylactic bilateral mastectomy, and prophylactic bilateral oophorectomy. BRCA is not associated with a signifi cant increase in the risk of endometrial cancer, and hysterectomy alone has not been associated with reduced risk of breast cancer. Section: Assessment of breast cancer risk.

A 25-year-old woman is brought to the emergency department after involvement in a low-speed motor vehicle collision. She complains of feeling light-headed and states that she is 33 weeks pregnant. Vital signs are heart rate—90 beats/minute and BP—82/44 mm Hg. Abdominal examination reveals a gravid uterus but no tenderness. Chest x-ray is unremarkable, and FAST reveals no intraperitoneal fl uid. A viable intrauterine pregnancy is noted, and fetal heart tones are observed. The next step in management should be A. cesarean section. B. induction of labor with vaginal delivery. C. left lateral tilt positioning. D. diagnostic peritoneal lavage. E. MRI of the abdomen and pelvis.

Answer: C In the supine position, the gravid uterus compresses the inferior vena cava (IVC), resulting in decreased venous return to the heart and hypotension. Visibly pregnant trauma patients should be placed in the left lateral tilt position (while maintaining spinal precautions) to displace the gravid uterus from the IVC. Induction of labor and cesarean section would not be indicated in the absence of fetal distress. Diagnostic peritoneal lavage (DPL) is relatively contraindicated in pregnancy, as uterine or fetal injury may occur. MRI is not utilized in the acute evaluation of abdominal trauma.

A 51-year-old woman comes to clinic because of a mass in the left breast for 2 weeks. She has no previous history of breast problems. Her last menstrual period was 1 week ago, menarche was at age 12 and she had her first child at age 30. She has no history of any major medical illness. Her paternal aunt had breast cancer at age 75. On physical examination, she has a 1-cm mass in the upper outer quadrant of the left breast. The mass is firm and freely movable with indistinct borders. There is minimal tenderness and skin dimpling over the mass. There is no nipple discharge and no axillary lymphadenopathy. The mammogram and breast ultrasound are normal. A biopsy shows cancer. Which of the following is the most likely histologic type of cancer causing these findings? A. Inflammatory B. Infiltrating ductal C. Infiltrating lobular D. Lobular carcinoma in situ E. Paget's disease

Answer: C Infiltrating lobular often presents as described in this patient. Inflammatory breast cancer will have red edematous skin. Infi ltrating ductal carcinoma will be hard with irregular borders and will usually be seen on mammogram and ultrasound. Lobular carcinoma in situ does not usually present as a mass. It is usually found incidentally when excising other breast pathology. Paget's disease involves the nipple. Section: Histologic types of breast cancer.

A 52-year-old woman comes to clinic because of a bloody nipple discharge. She has noticed spontaneous bloody nipple discharge from her left breast every 2 to 3 days for the last month. She has no pain and takes no medications. Menarche was at age 12. She has four children and was 22 years old when her first child was born. There is no family history of breast cancer. There are no palpable breast masses, but a small amount of bloody discharge can be expressed from the upper inner quadrant of the left nipple. A mammogram done earlier today was read as normal. What is the most important next step in her evaluation? A. Breast MRI B. Ductography C. Duct excision D. Cytology of the discharge E. Additional mammographic views with the focus on the retroareolar region

Answer: C MRI is not useful in the evaluation of nipple discharge. Ductography will not avoid the need for duct excision. Cytology has been shown to be unhelpful in the workup and diagnosis of nipple discharge. A signifi cant percentage of patients with nipple discharge have no mammographic abnormalities. Section: Benign conditions of the breast: nipple discharge.

A 54-year-old man presents to the clinic with abdominal pain over the past 8 hours. The pain is mid-abdominal and getting worse. Your evaluation has found an elevated white blood cell count, an amylase of 792 U/L, and normal liver function tests. An ultrasound reveals gallstones. Which of the following is the most appropriate management at this time? A. Give the patient a prescription for pain medicine and have the patient return to the clinic in 1 week for a checkup. B. Admit the patient to the hospital, start antibiotics, monitor the amylase levels, and discharge the patient when the amylase levels have returned to normal. C. Admit the patient to the hospital, hold any intake by mouth, and schedule the patient for a cholecystectomy before discharge. D. Schedule the patient for emergency exploratory laparotomy. E. Call a code, intubate the patient, and admit the patient for treatment in the intensive care unit.

Answer: C Most patients with gallstone pancreatitis resolve the episode of pancreatitis with bowel rest and hydration. The incidence of recurrent pancreatitis is high unless the gallbladder is removed. Patients should have a cholecystectomy, therefore, before discharge as long as the patient is a reasonable operative candidate

A 43-year-old woman comes to the emergency department with a 3-day history of abdominal distention, nausea, and vomiting. She also reports decreased urine output over the last 24 hours. She has a history of total abdominal hysterectomy 5 years ago for benign disease. She does not take any medications. Her pulse is 110 beats/minute. Her abdomen is distended and there is mild diffuse tenderness. Bowel sounds are hyperactive. The rest of her exam is normal. Serum electrolytes are sodium—140, chloride—90, bicarbonate—32, and potassium—4.0. Which of the following is the most appropriate initial intravenous fluid to administer to this patient? A. D5 ½ normal saline with 40 mEq KCl/L B. Lactated Ringer's solution C. Normal saline D. Colloidal starch solution E. 5% albumin in normal saline

Answer: C Potassium should not be added until volume restoration is achieved, lactated Ringer's may worsen metabolic alkalosis because the lactate is converted to bicarbonate in the liver, and colloidal solutions do not correct the hypochloremia and electrolyte imbalances and are not called for in resuscitating the hypovolemic dehydrated patient.

A 42-year-old man comes to the emergency department with severe abdominal pain. He takes no medications. He drinks a quart of vodka daily and smokes one to two packs of cigarettes daily. Temperature is 38°C, BP is 110/90, pulse is 20/ minute, and respirations are 24/minute. He has severe epigastric tenderness. Which of the following variables is included in Ranson's criteria on admission to predict the severity of this patient's illness? A. Calcium B. Arterial PO2 C. WBC D. Base deficit E. Total bilirubin

Answer: C Ranson's criteria is one of the grading systems for the severity of pancreatitis that relies on clinical and laboratory values on admission and during the initial 48 hours. On admission, the criteria include age, WBC, serum glucose, serum LDH, and SGOT. Arterial PO2, calcium, and base deficit are three of six criteria measured during the initial 48 hours. Total bilirubin, although often measured, is not part of the criteria. (Taken from Acute Pancreatitis, Prognosis).

A 25-year-old man is in the hospital recovering from open surgery for perforated appendicitis performed 5 days ago. Postoperatively his wound was left open with daily debridement and local dressing changes. Today, local anesthesia is applied and the wound is closed with a nylon suture at the bedside. This represents an example of A. primary closure. B. composite graft closure. C. delayed primary closure. D. healing by secondary intent. E. local flap closure.

Answer: C Surgical wounds can heal in several ways. An incised wound that is clean and suture closed is said to heal by primary intention. Primarily closed wounds are of a smaller volume in a clean surgical fi eld. Often, because of bacterial common contamination or tissue loss, a wound will be left open to heal by granulation tissue formation. This is healing by secondary intent, and the wound must synthesize granulation tissue, contract at the wound periphery, and eventually cover the surface area with epithelial cells. Delayed primary closure represents a combination of the fi rst two, consisting of the placement of sutures, allowing the wound to stay open for a few days, and then subsequent closure of the sutures. Delayed primary closure requires that the wound be free of excess bacteria. This is generally accomplished by good local wound care with irrigation and debridement if necessary during a postoperative interval. Wounds heal faster following delayed primary closure than by secondary intent.

A 50-year-old man has the onset of chest pain shortly after he undergoes pneumatic dilatation of the lower esophageal sphincter to treat achalasia. An upper gastrointestinal (GI) water-soluble contrast study shows free extravasation of the contrast material at the level of the distal esophagus. The decision is made to take the patient to the operating room for immediate repair. The best surgical incision to use is a(n) A. median sternotomy. B. right thoracotomy. C. left thoracotomy. D. abdominal incision. E. left thoracoabdominal incision.

Answer: C The best exposure of the distal thoracic esophagus is through a left thoracotomy.Anatomically, the upper and middle thoracic esophagus runs along the right side of the aorta, but the distal esophagus swings anterior and then to the left of the aorta to exit into the abdomen. The esophagus is not accessible through a median sternotomy because it lies in the posterior mediastinum with the heart lying anterior to it. A right thoracotomy is used to expose the proximal and middle thoracic esophagus. A left thoracoabdominal incision is a large morbid incision and is not necessary for the repair of the perforation and to perform a myotomy.

A 63-year-old woman comes to clinic with symptoms of nonspecific abdominal pain. Her past medical history is unremarkable. She takes vitamins and calcium supplements. A recent CT scan shows a small bowel mass lesion. Laboratory evaluations show an elevated serum level of c-kit protein, with normal chromogranin A. Which of the following intestinal tumors is this consistent with? A. Hamartomas B. Brunner's gland adenoma C. Gastrointestinal stromal tumor D. Carcinoid tumor E. Osler-Weber-Rendu lesion

Answer: C The elevated c-kit level is specific to gastrointestinal stromal tumor (GIST) tumors and is the key information leading to this answer. The other small bowel lesions mentioned could present with similar vague symptoms but are not associated with the c-kit proto-oncogene mutation and associated serum protein marker. Carcinoid tumors may be associated with elevated levels of 5-HIAA (5-hydroxyindole acetic acid) on 24 urine testing. Osler-Weber-Rendu lesions are telangiectasias and may be associated with bleeding and characteristic visible telangiectasias in other mucosal areas including the oral cavity and skin. Hamartomas may be associated with Peutz-Jeghers syndrome. Brunner's gland adenomas are seen in the proximal duodenum, where these glands are part of the mucus and alkaline mucosal protection mechanism of the proximal small intestine.

A 70-year-old woman is brought to the clinic by her family because of jaundice. She has also had a 20-pound weight loss over the past few months and has recently noticed very dark urine and light-colored stools. She does not have any pain. She is thin. There is a nontender, globular mass in the right upper quadrant. An ultrasound shows dilated intrahepatic and extrahepatic bile ducts with a dilated pancreatic duct and a mass in the head of the pancreas. Mutations in which of the following is most likely associated with this patient's diagnosis? A. p53 B. p16 C. K-ras D. DNA mismatch repair E. Retinoblastoma (RB) gene

Answer: C The most commonly expressed genetic mutation in pancreatic cancer occurs in the K-ras oncogene. It is present in at least 75% of pancreatic carcinomas. Mutations in the p53 tumor suppressor gene are the second most common mutation in pancreatic cancer and the most common genetic event in all human cancers. Mutations in other genes including p16, the retinoblastoma gene, and in the DNA mismatch repair genes also occur but are less common. (Taken from Pancreatic Neoplasms, Genetic Mutations Associated with Pancreatic Cancer).

A 52-year-old man is in the operating room undergoing an emergent laparotomy because of a perforated ulcer. There is free intraperitoneal perforation and approximately 2 L of murky green fl uid with obvious vegetable matter is suctioned from the peritoneal cavity. A Graham patch is performed to close the perforation. The abdomen is irrigated with normal saline and suctioned until all return is clear of green fl uid and vegetable matter. After closing the fascia the next most appropriate step would be A. interrupted skin closure. B. closure of skin with a skin closure polymer (i.e., Dermabond). C. wound left open and wound care until clean and granulating and then delayed closure. D. closure of skin with staples. E. subcuticular suture skin closure.

Answer: C This is a contaminated surgical fi eld. Wound infection in this setting can be as high as 15% of wounds, regardless of irrigating until clear. Allowing the wound to stay open with wound care until robust granulation is occurring and the wound bed is clean reduces this risk once the delayed closure is done. If the wound granulates but continues to have a high bacterial load, it can be allowed to heal by secondary intention.

A 63-year-old man with chronic obstructive pulmonary disease (COPD) caught his home on fi re while smoking in bed. He was trapped in the house for an unknown time period before fi refi ghters extricated him. He presents to the Emergency Center with severe facial blistering, singed nasal hairs, black intraoral mucosa, a swollen tongue, and carbonaceous sputum. His pulse oximetry reads 85% on room air, and he is obtunded. What is the next best step in management? A. Administer racemic epinephrine and steroids. B. Draw an arterial blood gas for carboxyhemoglobin levels. C. Secure his airway by endotracheal intubation. D. Place him on 10 L oxygen by humidifi ed facemask. E. Transfer him to the hyperbaric oxygen chamber.

Answer: C This man presents with every manifestation of inhalation injury, which is the most frequent cause of death in victims of structural fi res. Oxygen therapy is essential, but this man likely does not have an adequate airway. Securing his airway is the fi rst principle of treatment. Section: Initial Care of the Burn Patient. Subsection: Primary Survey

A 19-year-old man is seen in the emergency department 20 minutes after a high-speed head-on collision with a tree, in which his car caught fi re. He was not wearing a seat belt and was ejected from the vehicle. In the emergency department, he is alert, but he does not remember what happened. He admits to drinking a few beers earlier. Blood pressure is 75/40 mm Hg and heart rate 140. His airway is patent. Breath sounds are equal bilaterally. Arterial blood gases reveal a PaO2 of 140, SaO2 of 98%, PaCO2 of 34, and pH of 7.33. He has burns to 15% TBSA, involving his anterior trunk and legs. His abdomen is covered with burns but appears distended; tenderness is hard to determine because of painful burn wounds. What is the most likely cause of his hypotension? A. Smoke inhalation injury B. Burn shock C. Intra-abdominal hemorrhage D. Ethanol intoxication E. Closed head injury

Answer: C This patient illustrates the importance of the secondary survey in victims of burn injury. This man's burns are too limited in extent to cause severe shock, especially so soon after injury. Smoke inhalation is doubtful, especially with good blood gases. There is no evidence for ethanol intoxication or closed head injury. Unless a second injury (i.e., abdominal trauma) is considered, it will not be diagnosed. Section: Initial Care of the Burn Patient. Subsection: Secondary Survey

A 55-year-old man is seen in clinic prior to undergoing elective repair of a large umbilical hernia. He is otherwise healthy and has had no previous surgery. He takes no medications. He does not smoke and does not drink alcohol. Except for a large reducible umbilical hernia, his physical exam is normal. Which micronutrient supplementation would NOT be beneficial to this patient to improve wound healing? A. Vitamin C B. Vitamin E C. Vitamin K D. Vitamin A E. Zinc

Answer: C Vitamins integral for wound healing are vitamin C and vitamin A. Vitamin C is required for the conversion of proline and lysine to hydroxyproline and hydroxylysine. Vitamin C defi ciency or scurvy leads primarily to the failure of collagen synthesis. Vitamin E is an antioxidant, aids in immune function and fi broblast stimulation, and inhibits prostaglandin synthesis. Selenium is important for lymphocyte function and protects membranes from free radical damage. Zinc is possibly the most essential element for wound healing. Zinc defi ciency leads to decreased fi broblast proliferation, decreased collagen synthesis, and likely decreased lymphocyte, cellular, and immunity. While vitamin A defi ciency impairs wound healing, supplemental vitamin A benefi ts wound healing. Vitamin A enhances immune function, macrophage proliferation, collagen synthesis, and epithelial integrity. Supplemental vitamin A therapy can improve wound healing in patients receiving corticosteroids, cancer patients, diabetics, and patients undergoing chemotherapy. Vitamin K is involved in coagulation factor formation.

A 46-year-old man with an enterocutaneous fistula has been maintained on TPN for several weeks. The fistula has healed and prior to removing the central line, the patient is given a unit of packed red blood cells through his central line for his chronic anemia. Two hours into his red cell infusion, a rapid response is called when the nurse discovers the patient comatose and hypotensive. What is the most likely cause of the patient's condition? A. Hypokalemia B. Transfusion reaction C. Hypoglycemia D. Air embolus E. Catheter-related sepsis

Answer: C When long-term infusion of highly concentrated glucose solutions is suddenly discontinued, the increased endogenous insulin levels precipitate hypoglycemia. A blood transfusion would be more likely to elevate rather than depress potassium levels. Transfusion reactions cause fever, back pain, hemolysis, and hypotension, but not coma. The air embolus could cause both shock and unconsciousness and is unlikely to be associated with a blood transfusion. Catheter-related sepsis could induce fever and hypotension, but not coma. (Transition from Parenteral to Enteral Nutrition)

A 68-year-old woman in the surgical intensive care unit is comatose 10 days after a motor vehicle crash during which she sustained a fractured right femur treated with an intramedullary rod within 24 hours of the injury. There were no other injuries noted on admission. She remains intubated due to hypoventilation. Vital signs are blood pressure (BP)—100/60 mm Hg and pulse—52 beats/minute. Her temperature is 35.4°C. Her chest is clear. There are no heart murmurs. Her abdomen is mildly distended but soft. There are no bowel sounds. The surgical site is healing well with no signs of infection. An electrocardiogram shows sinus rhythm with low-voltage QRS. Computed tomographic scan of her head is normal for her age. Laboratory studies show: Hemoglobin—8.2 g/dL Sodium—138 mEq/L Potassium—3.7 mEq/L Thyroid-stimulating hormone (TSH)—16.4 μU/mL (ref—0.5 to 5.0 μU/mL) T4—0.5 μg/dL (ref—5 to 12 μg/dL) What is the most likely diagnosis for her condition? A. Sick euthyroid syndrome B. Thyroid storm C. Myxedema coma D. Adrenal insufficiency of critical illness E. Graves' disease

Answer: C While rare, myxedema coma is the most severe form of hypothyroidism. Typical features of this condition include mental status changes ranging from lethargy to coma, hypothermia, sinus bradycardia, low-voltage QRS complex on electrocardiogram (ECG), hypoventilation, and ileus. An elevated TSH and severely depressed T4 levels confi rm the diagnosis. Sick euthyroid syndrome may be an adaptation to critical illness and is noteworthy for a depressed T3 level. Thyroid storm is severe hyperthyroidism and has features opposite of myxedema coma, including fever, high-output cardiac failure, and nearly nondetectable TSH with elevated T3 and T4 levels. The hallmark of adrenal insuffi ciency of critical illness is hypotension refractory to fl uids and vasoactive medications.

A 55-year-old man with known cirrhosis presents to the emergency department with severe abdominal pain. He appears ill. Blood pressure (BP) is 90/50 mm Hg, pulse is 110 beats/minute, respirations are 24/minute, and temperature is 38.8°C. The abdomen is distended and tender; a fluid wave is present. Blood test results are Hgb—13 g/dL, WBC—16,500/μL, normal electrolytes, urea nitrogen—10 mg/dL, and creatinine—1.1 mg/dL. A CT scan shows a small shrunken liver, an enlarged spleen, and a large volume of ascites. The ascites is sampled by paracentesis and the results of this analysis are WBC—750 cells/mL with 90% neutrophils; cultures are positive for a single Gram-negative aerobic organism. Which of the following is the most likely diagnosis? A. Perforated viscus B. Carcinomatosis C. Mallory-Weiss tear D. Spontaneous bacterial peritonitis E. Hepatorenal syndrome

Answer: D A. Incorrect. A perforated viscus is usually associated with free air on CT and plain fi lms and will almost always show a polymicrobial infection on wound culture. In addition, the WBC count of the ascites in this setting is much greater, typically higher than 10,000. B. Incorrect. Carcinomatosis can present with ascites, but this is usually gradual in onset and unassociated with severe pain. In addition, the liver size should be normal in size and contour and tumor nodules are usually visible throughout the abdomen. C. Incorrect. A Mallory-Weiss tear occurs following forceful vomiting and results in signifi cant upper GI hemorrhage. Ascites should not occur in this setting. D. Correct. Spontaneous bacterial peritonitis (SBP) is thought to occur in the setting of ascites with immunosuppression (cirrhosis) and is a marker of advanced, end-stage liver disease. Bacterial translocation across the gut is thought to be the leading cause in most cases. E. Incorrect. Hepatorenal syndrome (HRS) may occur in patients with advanced liver failure (cirrhosis) or fulminant liver failure. This condition is usually fatal unless the patient receives a liver transplant. In HRS, the kidneys are grossly and microscopically normal and usually have return of normal renal function, once a normal liver is in place.

A 55-year-old man with known cirrhosis presents to the emergency department with severe abdominal pain. He appears ill. BP is 90/50 mm Hg, pulse is 110 beats/minute, respirations are 24/ minute, and temperature is 38.8°C. The abdomen is distended and tender; a fl uid wave is present. Blood test results are Hgb—13 g/dL, WBC—16,500/μL, normal electrolytes, urea nitrogen—10 mg/dL, and creatinine—1.1 mg/dL. A CT scan shows a small shrunken liver, an enlarged spleen, and a large volume of ascites. The ascites is sampled by paracentesis and the results of this analysis are WBC—750 cells/mL with 90% neutrophils; cultures are positive for a single Gram-negative aerobic organism. Which of the following is the most appropriate immediate therapy? A. Exploratory laparotomy B. Intraluminal antibiotics C. Protein restriction D. Intravenous antibiotics E. Albumin

Answer: D A. Incorrect. Exploratory laparotomy is never required for SBP, since the cause is bacterial contamination of the ascitic fl uid, and this almost always resolves with appropriate antibiotic therapy. In addition, exploratory laparotomy will place the patient at great risk to wound breakdown and ascitic fl uid leak, which can be associated with disastrous consequences. B Incorrect. Intraluminal antibiotics (e.g., neomycin) are sometimes used for treatment of hepatic encephalopathy, but because they are not absorbed from the GI tract, they are ineffective for treatment of systemic infection. C. Incorrect. Protein restriction is sometimes required for treatment of hepatic encephalopathy but will have no effect on SBP. D. Correct. In cases of SBP, culture of the ascitic fl uid often shows a single organism but may not result in positive growth and clinical treatment decisions are made on an empiric basis, with antibiotic selection usually targeted toward enteric organisms. E. Incorrect. Intravenous albumin has been shown to be benefi cial for the treatment of associated renal insuffi ciency in patients with cirrhosis and SBP. However, this therapy would be considered an adjunct in their management and not primary treatment of the SBP per se.

A 70-year-old woman is transferred from the surgery ward to the surgical intensive care unit because of hypotension 2 days after undergoing an open low anterior resection for a sigmoid cancer. The surgery went well with minimal blood loss. The tumor was found on routine colonoscopy, and she had no symptoms and was quite healthy and active prior to surgery. Her preoperative medications were multiple vitamins and calcium supplements. Since surgery she has been receiving maintenance intravenous fl uids and was stable until a few hours ago when she became hypotensive. Despite receiving boluses of normal saline and starting pressors (norepinephrine and vasopressin), she remains hypotensive. She is intubated because of lethargy and tachypnea. Her temperature is 37.4°C. Pupils are equal and reactive. Her chest is clear bilaterally. There are no heart murmurs. Her abdomen is soft and tender only near the lower midline incision. There are no localizing neurological findings. There is minimal urine output from a Foley catheter. Laboratory studies show: Hematocrit—33% (36% the day before) Sodium—129 mEq/L Potassium—5.1 mEq/L Glucose—108 mg/dL Arterial blood gases (ABGs) on 40% FiO2-pH—7.39 PCO2—38 mm Hg PO2—130 mm Hg U/A—no bacteria, negative leukocyte esterase What is the most likely diagnosis? A. Hemorrhage B. Anastomotic leak C. Pulmonary embolism D. Acute adrenal insufficiency E. Urosepsis

Answer: D Adrenal insuffi ciency of critical illness typically presents with hypotension refractory to fl uid resuscitation and vasoactive medications. Ventilator dependence, hyponatremia, hyperkalemia, and hypoglycemia can occur but are less commonly attributed to the adrenal dysfunction. While frequently seen with chronic adrenal insuffi ciency, hyperpigmentation, abdominal pain, nausea, weight loss, and fatigue are not typical symptoms in the critical care setting.

A 65-year-old woman comes to clinic with a vague history of diffuse abdominal discomfort over the past 3 weeks. She denies any history of trauma or prior abdominal surgery and has no known stigmata of peripheral vascular disease. She takes vitamin D and calcium supplements. On exam, she has diffuse mild to moderate subjective tenderness without guarding or peritoneal signs. She is in sinus rhythm on EKG. Which of the following is the most likely diagnosis? A. Superior mesenteric artery thrombosis B. Superior mesenteric artery embolus C. Nonocclusive mesenteric ischemia D. Mesenteric venous thrombosis E. Aortic dissection

Answer: D Others typically present with more acute or sudden symptomatology

A 35-year-old man is admitted for a sigmoid colectomy due to repeated episodes of acute diverticulitis. He weighs 140 kg, but his ideal body weight is 80 kg. Which of the following body compositions should be used as a basis for calculating basic maintenance fluids for this patient? Total Body Water (L) Intracellular Water (L) Extracellular Water (L) Blood Volume (L) A. 84 55 28 9.8 B. 70 55 15 8.4 C. 56 35 21 8.4 D. 54 32 22 5.4 E. 60 40 20 7.5

Answver: D The composition of the body varies with lean body mass (muscle) and the fat content. If one assumes that "ideal body weight" is related to the theoretical "young healthy male" discussed in most textbooks where total body water is 60% of weight and intracellular volume is 60% of total body water, then for 80 kg, the patient would have 48 L of total body water, 32 L of intracellular water, and 16 L of extracellular water. Since fat is only about 10% water, the extra 60 kg of fat only adds 6 L of water. Therefore in this patient, total body water would only be 54 L. Intracellular water changes little and therefore the ICF would be about 32 L and the ECF about 22 L. Vascular volume for the 80-kg weight would only be a little more than 6% of weight (6.3 ± 0.4%) or about 5 L. The additional 6 L of fat would add little to the blood volume so 5.4 L total blood volume would be a close approximation. The clinical signifi cance of these "estimations" relates to numerous clinical scenarios. For example, if one estimates that there is a serum sodium defi cit of 10 mEq/L in this patient but assumes total body water is 60% of total weight, the patient would get 10 × 84 L of total body water or 840 mEq of sodium instead of 10 × 54 L of total body water or 540 mEq of sodium. The extra and unnecessary 300 mEq of sodium is equivalent to 2 L of normal saline. If one calculates total body water requirements for daily maintenance using the standard "70-kg male" as a reference, then the 140-kg male would receive 35 mL/kg (Table 2-2) or about 4.9 L of fl uid. However, using "ideal body weight" for the calculation and adding only about 10% for the increased fat content, the total fl uid would instead be about 3 L. If the extra 1.9 L is given over 3 or 4 days and if the kidneys do not excrete this fl uid due to numerous conditions such as syndrome of inappropriate antidiuretic hormone (SIADH), the patient in 3 days is up almost 6 L that may not be visible in this obese patient. This increased total body water could result in a host of effects including peripheral edema, pleural effusions, and cardiac and pulmonary dysfunction; lead to subtherapeutic drug levels (since many drugs such as antibiotics have volumes of distributions equivalent to extracellular or total body water); cause secondary complications from each of these effects and overall delay in discharge from hospital; and increase costs. In other words, a more accurate "guesstimate" using a similar thought process for patients decreases complications, reduces hospital stay, and reduces costs.

A 30-year-old man is in the intensive care unit where he is being treated for injuries sustained in a motor vehicle crash. He sustains multiple orthopedic injuries and a severe head injury. On hospital day 4, vital signs are BP—120/70 mm Hg, pulse—76/minute, and respiratory rate on a ventilator of 12/minute. His urine output is 20 mL/hour. Serum sodium is 120 mEq/L, BUN is 18 mg/dL, and creatinine is 1 mg/dL. What is the most likely diagnosis? A. Water intoxication due to inappropriate fluid infusion B. Central diabetes insipidus C. Lab error D. SIADH E. Increased aldosterone secretion due to hypovolemia

Answer: D Although water intoxication due to inappropriate fl uids is possible, in this patient it is unlikely since he has normal renal function as refl ected by his BUN and creatinine. If he were given inappropriate fl uids, he would diurese the extra fl uid. Central diabetes insipidus usually results in a marked increase in urine (free water) output and would result in an increase in sodium concentration. Laboratory error is always possible, and if there is any question of this possibility, the electrolytes should be rechecked prior to initiating therapy. Increased aldosterone secretion would result in sodium retention and therefore would maintain serum sodium concentration. The most likely scenario is an increase in ADH, in this case due to the increase in intracranial pressure due to the head injury. Since the patient has a wide pulse pressure and normal output, he is at least euvolemic. Therefore, an increase in ADH is "inappropriate" for the situation. If, however, the patient had signs of decreased vascular volume including a narrow pulse pressure and increased heart rate, then the increased ADH secretion would be "appropriate".

A 46-year-old man comes to your office 6 months after an open inguinal hernia repair complaining of pain, which has never resolved after his surgery. On further questioning, he complains of radicular pain into the testicle, which worsens with sitting for longer than 10 minutes. On exam, he is hyperesthetic overlying his scar and has numbness over the ipsilateral scrotum and medial thigh. All else is normal. Injury to which nerve is the most likely cause for his pain? A. Femoral nerve B. Hypogastric nerve C. Lateral femoral cutaneous nerve D. Ilioinguinal nerve E. Vagus nerve

Answer: D Because of its path alongside the spermatic cord, lying on top of the internal oblique muscle, the ilioinguinal nerve is susceptible to entrapment by most anterior repair techniques. The symptoms described by this patient are most consistent with the distribution of sensory innervation of the ilioinguinal nerve.

A 57-year-old man comes to clinic with complaints of foul-smelling urine and two urinary tract infections treated with antibiotics by his primary care physician over the past 6 weeks. He has no pain at this time. Two months ago, he was seen in the emergency department with 2 days of left lower quadrant pain and constipation and was treated with oral antibiotics for diverticulitis. His past history is otherwise negative. His only medication is ciprofloxacin. He is afebrile and vital signs are normal. A urine sample is cloudy with sediment. What is the next best step in diagnosis? A. Plain radiographs of the abdomen B. Ultrasound of the abdomen and pelvis C. Barium enema D. CT scan of the abdomen and pelvis E. Diagnostic cystoscopy

Answer: D CT scan remains the most sensitive test for diagnosis of enterovesical fistula and location of the portion of the intestinal tract involved. Plain radiographs may show air in the bladder, but not the etiology. Ultrasound has no role. Barium enema identifi es the fi stula <50% of the time. Cystoscopy usually identifi es only bullous edema within the bladder.

A 28-year-old ultimate fighter is seen in clinic 2 weeks after undergoing splenectomy for a ruptured spleen sustained during a prize fi ght. He is feeling well with minimal incisional pain. There is a midline laparotomy incision that appears to be healing well without evidence of infection or other problems. He wants to know when his incision will be healed enough for him to return to professional fi ghting. Regarding the tensile strength of his wound, A. it will increase steadily over the first 6 weeks and achieve maximal strength by 12 weeks. B. it will achieve maximal tensile strength at the point of maximal collagen deposition. C. it will take a full year for the wound to regain the same tensile strength as preoperatively. D. wound tensile strength reaches 90% at 26 weeks and this is its plateau. E. collagen deposition reaches a maximum level in the fi rst 6 weeks and is quickly degraded thereafter.

Answer: D Collagen secretion is initiated by fi broblasts in the fi rst 24 to 72 hours after injury. Peak collagen production begins by 1 week postinjury. By 3 weeks after injury, collagen synthesis and collagen deposition/degradation achieve a steady state. After 3 weeks, wound tensile strength remains <30%. As the maturation process takes place, tensile strength increases consistently until it plateaus approximately 6 months (26 weeks) after injury. This strength is generally around 90% of original tensile strength, and preinjury tensile strength will never be reached.

A 30-year-old man is brought to the emergency department after crashing his motorcycle at high speed into a concrete divider. He sustains severe trauma to the mid face and mandible and is lethargic upon arrival. He has copious amounts of bloody airway secretions and pulse oximetry reveals oxygen saturation levels of 82% to 85%. Two unsuccessful attempts have been made to place an orotracheal tube. The next step should be A. bag-valve mask ventilation. B. nasotracheal intubation. C. resuscitative thoracotomy. D. surgical cricothyroidotomy. E. bronchoscopy.

Answer: D In the primary survey, obtaining a patent airway is of paramount importance. The patient in this scenario has an unstable airway and poor systemic oxygenation, making the establishment of a defi nitive airway an urgent matter. Since orotracheal intubation attempts have failed, the next step is to perform a cricothyroidotomy. Bag-valve mask ventilation is unlikely to be successful in this circumstance and does not provide a defi nitive airway. Nasotracheal intubation is contraindicated in severe facial trauma as false passage into the cranium may occur. Resuscitative thoracotomy may restore circulation but does not provide an airway. Bronchoscopy may be utilized after establishment of an airway to clear blood or secretions. (Taken from Primary Survey: Airway).

A 51-year-old woman comes to the emergency department because of fever and abdominal pain. Her temperature is 38.4ºC. She is tender with guarding in the right upper quadrant of her abdomen. Her WBC is 17,000/mm3. LFTs and lipase levels are within the normal range. Ultrasound of the right upper quadrant identifies gallstones, a gallbladder wall of 5 mm, and fluid surrounding the gallbladder. The most appropriate antibiotic to treat this condition is A. penicillin. B. ciprofloxacin. C. metronidazole. D. cefoxitin. E. linezolid.

Answer: D Most bacteria that infect the biliary tree are Gram-negative rods and include E. coli and Klebsiella. A second- or third-generation cephalosporin will effectively cover these bacteria. The other choices may target these bacteria as effectively or are reserved for advanced complex infections.

A 66-year-old man is in the intensive care unit 10 days following colon resection for perforated diverticulitis. He has a history of chronic obstructive pulmonary disease (COPD) and is unable to wean from the ventilator. He has been maintained on total parenteral nutrition (TPN) and has started tube feeding. The most likely nutritional cause for failure to wean from the ventilator would be A. too much protein. B. refeeding syndrome. C. underfeeding. D. overfeeding. E. hyperphosphatemia.

Answer: D Patients with COPD have diffi culty weaning from the ventilator secondary to CO2 retention. Feeding with both TPN and enteral feeding is likely to provide glucose loads far in excess of 4 g/kg/day, resulting in lipogenesis. The respiratory quotient (RQ) for lipogenesis is 8.7, which signifi es a high CO2 production. This additional CO2 could make it very diffi cult for a COPD patient to wean from the ventilator. (Parenteral Nutrition Advantages and Disadvantages)

A 28-year-old man comes to clinic because of an inguinal hernia. He works as a stonemason and first noticed the hernia when he developed a painful bulge while lifting a bag of cement. He has otherwise been healthy and takes no medications. An open inguinal hernia repair with mesh has been recommended. During a discussion of the anticipated risks, which of the following represents the most common complication? A. Recurrence B. Urinary retention C. Reduced fertility D. Chronic pain E. Ischemic orchitis

Answer: D Recurrence after open inguinal hernia repair is reported to be between 1% and 6%. Urinary retention is observed in approximately 10% of patients—particularly older men—and patients should be able to urinate before discharge home. Chronic neuropathic pain from nerve entrapment is observed in 6% to 13% of patients. Impaired fertility and ischemic orchitis from injury to the vas deferens and spermatic vessels, respectively, are rare complications (<5%).

A 42-year-old woman is seen in clinic 2 weeks after undergoing left partial mastectomy and sentinel lymph node biopsy for stage 1 breast cancer. Whole breast radiation is recommended. She is concerned about the effects of radiation on her incision. Which of the following statements is least accurate regarding radiation effects and wound healing? A. Rapidly dividing cells are the least affected by radiation therapy. B. Radiation effects on fibroblasts should be negligible. C. Radiation causes increased amounts of collagen deposition. D. Long-term effects of radiation are often reversible after 24 months. E. Wound healing is impaired postradiation secondary to venous injury.

Answer: D The effects of external beam radiation often cause local tissue damage and impaired wound healing. Given the sensitivity of radiation to the various phases of the cell cycle, rapidly dividing cells are the most sensitive to radiation. Two major manifestations of impaired wound healing secondary to radiation are the result of direct injury to fi broblasts, leading to a lack of collagen, and endothelial cell injury resulting in ineffi cient wound healing. The effects of radiation are permanent and irreversible cell damage, as manifested by progressive fi brosis and obliterate endarteritis.

A 27-year-old man is in the intensive care unit 24 hours after an automobile collision. He has a left pneumothorax, multiple broken ribs, a ruptured spleen requiring splenectomy, a pelvic fracture, and bilateral femur fractures. He is intubated. He has received 6 units of PRBCs and is currently receiving IV fluids. Which one of the following best describes his metabolic response? A. Insulin is the major mediator of the stress response. B. Glycogen stores can be used for 7 days. C. Energy expenditure is decreased by 30%. D. Hepatic reprioritization of protein synthesis favors acute-phase proteins. E. Epinephrine and adrenocorticotropic hormone (ACTH) production are reduced.

Answer: D The injury stress response is mediated by the counter-regulatory hormones, including ACTH, epinephrine, glucagon, and cortisol, along with the proinfl ammatory cytokines such as interleukins 1 and 6. Insulin is diminished during this response. The stress response results in the marked increase of energy expenditure, which is proportional to the size of the stress. Glycogen stores are rapidly depleted within 12 to 24 hours. Protein synthesis in the liver is reprioritized to produce acute phase proteins.

A 34-year-old woman is thrown from a horse during a trail ride and brought to the emergency department 60 minutes after the accident. She is awake but appears to be mildly confused. She complains of left chest pain that is worsened with inspiration as well as generalized abdominal pain. On exam, her airway is patent and breathing unlabored. Her pulse is 110 beats/minute. Her blood pressure is 85/62. Her breath sounds are equal bilaterally. Her neck veins are fl at and her skin is cool. She is tender over her left lower ribs and left upper quadrant. You suspect that she has sustained an injury to her spleen with resultant hemorrhage. Approximately what percentage of intravascular volume loss has she experienced? A. 0% B. 10% C. 20% D. 30% E. 50%

Answer: D The patient described in the scenario has suffered a splenic injury and progressive hemorrhage over the course of the hour leading up to presentation. She is demonstrating progressive hemodynamic effects from volume loss as described in Table 5-12, including mild tachycardia and hypotension, altered mental status, and decreased skin perfusion. Blood volume loss of 0% to 10% produces little change in hemodynamics or physical exam (answers A and B). Blood loss of 20% over 1 hour results in increased pulse, but normal blood pressure, mentation, and skin palpation (answer C). Blood loss of 30% is associated with mild hypotension, tachycardia, altered mental status, skin vasoconstriction, and decreased urine output (answer D; correct answer). Loss of 50% of blood volume is associated with severe physiological derangements, including profound hypotension, severe tachycardia, obtunded mental status, and anuria (answer E).

A 50-year-old woman is seen in clinic because of weight loss, restlessness, and palpitations. She also has noted leg swelling and excessive hair loss. Her past medical history is unremarkable. She takes no medications. She is afebrile. On exam, she is tachycardic and has a fine tremor. She has mild exophthalmos. Her thyroid is smooth and uniformly enlarged. TSH levels are low and T3 and T4 levels are elevated. What is the next best step in management? A. Radioactive iodine B. Early operation C. Propranolol D. Antithyroid medication E. Thyroxine suppression

Answer: D The patient has Graves' disease. Initial treatment should be with antithyroid medication to suppress thyroxine production. Radioactive iodine as the fi rst line of treatment is inappropriate because as many as 75% of patients have been reported to have sustained remission after 3 to 6 months of treatment with antithyroid drugs. Early operation is too aggressive when nonoperative methods of treatment are available. Propranolol may be used as an adjunct to antithyroid medications but used alone does not help suppress the thyrotropin receptor antibodies (TRAbs) that are responsible for Graves' disease. The highest rates of remission are associated with elimination of these antibodies. Thyroxine suppression will be ineffective since the patient already has high levels of T4. (Hyperthyroidism/Graves' Disease/Treatment)

A 60-year-old man comes to the emergency room because of hematemesis and bright red blood per rectum. He reports a history of gnawing epigastric pain radiating to the back and improved with eating. His past medical history is significant only for frequent headaches and back pain, for which he takes nonsteroidal anti-inflammatory drugs (NSAIDs) and over-the-counter medications. On physical exam, he is pale, hypotensive, and tachycardic. After resuscitation, initial upper endoscopy reveals evidence of an upper gastrointestinal hemorrhage and an ulcer in the posterior duodenal bulb. Which blood vessel is the most likely source of bleeding? A. Left gastric artery B. Right gastric artery C. Common hepatic artery D. Gastroduodenal artery E. Superior mesenteric artery

Answer: D The patient presents to the emergency room with evidence of a massive upper gastrointestinal hemorrhage (hematemesis with bright red blood with hypotension and tachycardia). His symptoms of gnawing epigastric pain radiating to the back and improved with eating suggest a posterior bulb duodenal ulcer. Ulcers in this location can erode into the gastroduodenal artery as it passes behind the fi rst portion of the duodenum, causing massive gastrointestinal hemorrhage. The left gastric artery arises from the celiac axis. The common hepatic artery divides into the gastroduodenal and proper hepatic arteries. The right gastric artery arises from the proper hepatic artery. The superior mesenteric artery is a branch off the aorta. (Anatomy; Benign Duodenal Ulcer/Uncomplicated Duodenal Ulcer/ Clinical Presentation and Evaluation; Complicated Duodenal Ulcer/ Clinical Presentation and Evaluation)

A 24-year-old female graduate student comes to the emergency department because of abdominal pain for the past 12 hours. Initially she had vague mid-abdominal pain that has localized to the RLQ about 3 hours ago. She is otherwise healthy and takes no medications. Her temperature is 37°C. There is guarding and rebound tenderness in the right lower quadrant and a positiveRovsing's sign. A CT scan shows fat stranding around a dilated appendix. At surgery, there is a 2.5-cm firm, smooth yellowish mass at the base of an infl amed appendix. There is no evidence of perforation and no other abnormalities are found. Frozen section biopsy is consistent with a neuroendocrine tumor. Which of the following is the most appropriate management at this time? A. Appendectomy to include the tumor B. Cecectomy C. Subtotal colectomy D. Right hemicolectomy E. Appendectomy followed by chemotherapy

Answer: D This patient has a carcinoid tumor. A right hemicolectomy is needed because of the heightened risk of lymph node metastases. A simple appendectomy would not be appropriate for a carcinoid at the base of the appendix but would be appropriate for a carcinoid tumor <2 cm at the tip of the appendix. Cecectomy would not adequately sample the regional lymph nodes, and a subtotal colectomy is not necessary. Adjuvant chemotherapy is not indicated for a localized carcinoid tumor.

A 62-year-old woman is seen in the emergency department with dark red rectal bleeding and hypotension. Initial hemoglobin is 7.2. She is given intravenous fluids and two units of packed red blood cells but continues to have large amounts of bloody stools. Nasogastric tube effluent is clear bilious fluid. The best choice for identification of the bleeding site at this time is A. rigid proctoscopy. B. bowel prep followed by colonoscopy. C. tagged red blood cell nuclear scan. D. mesenteric angiography. E. diagnostic laparoscopy.

Answer: D While rigid proctoscopy may be done, it is unlikely to identify a source of massive bleeding. The patient is unlikely to be sufficiently stable for the colonoscopy prep or the time required for it. Tagged RBC scan is more sensitive than angiography for identifying active bleeding, but much less specifi c for identifying the source of bleeding and is not as useful in massive bleeds. Diagnostic laparoscopy would not elucidate the bleeding source. Mesenteric angiography is much more specific for identifying the source and offers the potential for therapy (angiographic embolization) to control bleeding as well in selected cases.

A 32-year-old man comes to the emergency department with an acutely incarcerated inguinal hernia. With sedation, the hernia is reduced and he feels better. Eighteen hours later, he complains of increasing abdominal pain and has diffuse tenderness on examination. He most likely had which of the following? A. Diastasis recti B. Petit's hernia C. Epigastric hernia D. Amyand's hernia E. Richter's hernia

Answer: E A Richter's hernia involves only a portion of the circumference of a bowel wall and typically is recognized with bowel incarceration or strangulation (sometimes after reduction of the hernia, causing an acute abdomen when the bowel perforates). Diastasis recti is a fascial weakness, not a true fascial defect, and does not require surgical intervention. Petit's hernia is a broad, bulging hernia that usually does not incarcerate. Amyand's hernia contains the appendix and sometimes can present with fi ndings of appendicitis. Epigastric hernias typically are small and often contain preperitoneal fat only. They are often recognized early by the patient in the event that the hernia becomes incarcerated, and strangulation is unlikely to ensue.

An 83-year-old woman presents to the emergency department with a 2-day history of nausea and vomiting. She has a prior history of a hysterectomy, and on exam, her abdomen is slightly distended and nontender on palpation. Her laboratory evaluation reveals a normal white blood cell count and a metabolic alkalosis. Abdominal x-rays show a small bowel obstruction and air in the biliary tree. Which of the following is the most likely diagnosis? A. Colon cancer B. Perforated duodenal ulcer C. Acute cholangitis D. Small bowel obstruction secondary to adhesions E. Gallstone ileus

Answer: E By definition, a gallstone ileus results in air in the biliary tree since there is a fistula between the gallbladder and duodenum. If the stone is large enough to obstruct the ileocecal valve, the patient will manifest a bowel obstruction.

A frail 85-year-old man underwent upper endoscopy with dilation and biopsy of a distal esophageal stricture. Concerned about a perforation, the endoscopist obtained a water-soluble contrast upper GI study that confirmed a perforation. Nonsurgical management is acceptable if A. the patient has a new left pleural effusion. B. the patient has an obstructing carcinoma. C. the patient develops pain. D. the perforation is over 24 hours old. E. the upper GI study shows leak of contrast, which drains back into the esophagus.

Answer: E Conservative management is acceptable if contrast study shows a contained leak that drains back into the esophageal lumen. A new left pleural effusion is indicative of a more severe leak, which should not be managed conservatively. Obstructing lesions cannot be ignored, as any obstruction will exacerbate the leak. Pain is indicative of excessive leak of GI contents into the mediastinum and pleura, which cannot be managed conservatively. Duration of perforation should not dictate whether surgical intervention is or is not pursued.

A 71-year-old man is admitted to the intensive care unit in septic shock secondary to pneumonia. His BP is 85/40 mm Hg and heart rate 95 beats/minute. Which of the following medications would be the most appropriate to use to treat his hypotension? A. Epinephrine B. Dobutamine C. Milrinone D. Dopamine E. Norepinephrine

Answer: E Dobutamine is a beta-agonist. Milrinone is a phosphodiesterase inhibitor. Both are commonly used for the management of cardiogenic shock. Epinephrine and dopamine have mixed alpha- and beta-receptor activity. Dopamine also stimulates dopaminergic receptors. Tachycardia is a frequent side effect. Norepinephrine stimulates mainly alpha receptors, with some beta-receptor activity. Thus, it is the drug of choice for patients with distributive shock, for example, sepsis.

A 50-year-old woman comes to the clinic because of severe heartburn and regurgitation after meals and on lying down. She has been on long-term proton pump inhibitors with good relief of symptoms but now wants to have antireflux surgery. Her body mass index (BMI) is 32.4. The preoperative study most useful in predicting symptomatic relief from antireflux surgery is a(n) A. contrast barium swallow. B. CT scan of the chest and abdomen. C. upper endoscopy. D. esophageal manometry study. E. 24-hour pH monitoring study

Answer: E Evidence of abnormal acid reflux obtained from a positive 24-hour pH study is the best indicator for likely benefit of an antireflux procedure in gastroesophageal reflux disease (GERD). The other studies offered above can provide additional information on GERD but are not as sensitive in identifying potential surgical candidates for antirefl ux procedure. A barium swallow can identify a hiatal hernia, associated strictures, or shortened esophagus. A CT scan provides very little additional information but may demonstrate the presence of a hiatal hernia. Upper endoscopy is useful in identifying and monitoring progression of Barrett's disease. Manometric study, when abnormal, is useful in identifying motility dysfunction, which may affect surgical outcome.

A 26-year-old man is brought to the emergency department (ED) after being stabbed in the left arm in a fight. Brisk bleeding from the wound was controlled by the EMTs with a pressure bandage. Fifteen minutes later in the emergency department, the bandage is removed and only slight oozing is noted.The most likely mechanism for decreased bleeding at this time is A. platelet activation and aggregation. B. activation of the extrinsic coagulation cascade pathway. C. activation of prothrombin to thrombin. D. activation of the intrinsic coagulation cascade pathway. E. local peripheral vascular vasoconstriction.

Answer: E Hemostasis involves the blood vessel wall, platelets, and the coagulation cascade leading to fi brin deposition. After injury, local vasoconstriction is the fi rst hemostatic process to occur. This is followed by platelet adherence, activation, and aggregation. Finally, the coagulation cascade leads to the deposition of fi brin.

A 40-year-old man comes to clinic because of a large incisional hernia. One year ago, he underwent a splenectomy for a ruptured spleen following a motor vehicle crash. There is a large hernia in the epigastrium in the central portion of a long midline incision. A laparoscopic incisional hernia repair is recommended to the patient. Which of the following should be included in the discussion with the patient while obtaining informed consent? A. Risk of conversion from a laparoscopic procedure to a handassist procedure B. Whether the patient has insurance coverage C. The type of sutures used for mesh fixation D. The manufacturer of the prosthetic material E. The hernia recurrence rate

Answer: E In general, informed consent for a hernia repair should include the most common risks, which would include recurrence, chronic pain, urinary retention, and possible numbness of the area. If one needed to convert from a laparoscopic repair, the conversion would be to open, not hand assisted. While insurance coverage may be an issue for payment for the hospital, it is not part of informed consent, nor are the types and manufacturers of the materials used for the repair

A 41-year-old man is seen in clinic with bright red rectal bleeding, seen on the toilet tissue intermittently over the last several months. He is an insurance agent, exercises regularly, and eats a well-balanced diet. He denies changes in bowel habits. Family history is unremarkable. His vital signs are normal. His abdomen exam is normal. Digital rectal exam is normal, and blood is identified on the examining finger. Anoscopy shows no other pathology. What is the next best step in diagnosis? A. Fecal occult blood test B. Complete blood count (CBC): if normal, no further evaluation is indicated C. Barium enema D. Flexible sigmoidoscopy E. Colonoscopy

Answer: E In the absence of an obvious source in the anus or distal rectum, further evaluation of the colon is needed. Fecal occult blood test (FOBT) is irrelevant with a history of visible rectal bleeding. CBC is unlikely to be helpful. Flexible sigmoidoscopy only examines part of the colon. While barium enema may identify an abnormality anywhere in the colon, it is not as specific as colonoscopy.

A 22-year-old man is brought to the emergency department after falling from a 10-foot ladder, landing on his left side. He has multiple left-sided rib fractures and a pneumothorax requiring a chest tube. Physical examination of the abdomen is unremarkable. He remains hemodynamically stable throughout the primary and secondary surveys and undergoes contrast-enhanced CT scanning of the abdomen and pelvis. CT scan reveals a grade II laceration of the spleen, with no evidence of active contrast extravasation. The next appropriate step in management is A. exploratory laparotomy with splenectomy. B. exploratory laparotomy with splenorrhaphy. C. splenic angioembolization. D. video-assisted thoracoscopy with evacuation of hemothorax. E. observation with serial abdominal examinations.

Answer: E Most low-grade splenic injuries can be managed nonoperatively. The key factor is hemodynamic stability of the patient. In this patient, splenectomy and splenorrhaphy would represent unnecessary surgical options, and interventional techniques such as angioembolization should be reserved for cases of high-grade splenic injury with active extravasation of intravenous contrast. Thoracoscopy is indicated for evacuation of residual hemothorax or diagnosis of penetrating diaphragmatic injury. (Taken from Abdominal Injury: Injury to Specifi c Organs: Spleen).

An 85-year-old male nursing home resident is brought to the emergency department with 3 days of painless abdominal distention and obstipation. He appears to be in no pain, but his abdomen is massively distended and tympanitic. Plain abdominal films show a kidney-bean-shaped air-filled structure suspicious for cecal volvulus. The best management at this point is A. observation if the cecum is <12 cm in diameter. B. contrast enema decompression. C. colonoscopic detorsion, leaving a rectal tube. D. operative detorsion and fixation of the cecum to the abdominal wall. E. right colon resection.

Answer: E Observation occurs in Ogilvie's, not volvulus. Contrast enema decompression is not useful in cecal volvulus. Colonoscopic detorsion is useful for sigmoid volvulus, but considered unwise in cecal volvulus due to associated risks. Cecopexy carries a high rate of revolvulus.

Which of the following patients is at the lowest risk for postoperative deep vein thrombosis? A. An 18-year-old male with femur and lumbar fractures B. A 55-year-old morbidly obese female undergoing total knee replacement C. A 62-year-old man undergoing prostatectomy for cancer D. A 45-year-old woman undergoing hysterectomy and bilateralsalpingo-oophorectomy and debulking for ovarian carcinoma E. A 38-year-old woman undergoing carpal tunnel release

Answer: E Patients who are immobile, who have congestive heart failure or malignancy, who undergo pelvic or joint replacement operations, or who have vertebral, pelvic, or long bone fractures are at highest risk. Carpal tunnel release does not confer increased risk of deep vein thrombosis.

A 45-year-old man was admitted to the hospital 3 days ago with nausea and vomiting due to a gastric outlet obstruction. Further studies have confirmed a gastric cancer involving the antrum of the stomach. He has a history of alcohol abuse and being homeless. The patient is thin and has temporal wasting and exposed ribs. He has an albumin of 1.9 g/dL. A nasogastric tube was placed on admission, and he was started on TPN. What is his surgical risk for perioperative complications? A. Moderate risk for developing surgical complications B. Moderate risk for developing wound complications only C. Low risk for developing surgical complications D. Cannot assess risk for surgical complications E. High risk for developing surgical complications

Answer: E Patients with a poor baseline nutritional status undergoing surgery are more likely to have increased morbidity and mortality. There is a linear increase in complications in patients undergoing elective gastrointestinal surgery as preoperative albumin decreases from normal to levels below 2 g%. Criteria to consider when screening surgical patients for nutritional risk include magnitude of the procedure, medications, recent weight changes, cachexia, changes in diet or appetite, and serum albumin. (Assessment of Nutritional Status)

A 75-year-old woman with a history of congestive heart failure underwent elective sigmoid resection for severe recurrent diverticulitis. Postoperatively, she experiences shortness of breath. Physical exam and chest radiography suggest the presence of pulmonary edema. Which of the following parameters is the most accurate determinant of her left ventricular preload? A. Central venous pressure B. Pulmonary artery occlusive pressure C. Systemic vascular resistance D. Pulmonary venous pressure E. Left ventricular end-diastolic volume

Answer: E Preload is defi ned as the amount of myocardial stretch prior to myocardial contraction. Increased stretch leading to increased myocardial contraction is described by the Frank-Starling mechanism. Preload is most closely related to end-diastolic volume (answer E). Several other factors, including central venous pressure, pulmonary artery occlusive pressure, and pulmonary venous pressure, may also be used to estimate preload, but they are not as accurate as left ventricular end-diastolic volume for this purpose (answers A, B, and D). Systemic vascular resistance (C) is not mathematically related to preload.

A 74-year-old man has a recent diagnosis of adenocarcinoma of the distal esophagus. He has a long history of reflux and Barrett's esophagus, and a recent upper endoscopy and biopsies confirmed the diagnosis. A staging workup is planned. What is the best study for assessing T (tumor invasion depth)? A. Barium swallow B. CT scan with oral and intravenous contrast C. Upper endoscopy with rebiopsy D. Positron emission tomography (PET) scan E. Endoscopic ultrasound

Answer: E The endoscopic ultrasound is the best way to assess the depth of tumor invasion (T stage) and is also useful in identifying adjacent abnormal lymph node for fine needle aspiration (N stage). A barium swallow is a good initial study in the workup of dysphagia and helps locate the level of the lesion. A CT scan may show gross invasion of adjacent structures but cannot differentiate tumor depth. Upper endoscopy is used to obtain biopsies to confi rm carcinoma, but depth of invasion cannot be determined from the biopsy specimen. A PET scan is used to identify distant metastasis but does not have the resolution to determine tumor depth.

A 63-year-old man came to the office because of epigastric pain of 2 months' duration not relieved with antacids. He has a history of an adenomatous gastric polyp removed 3 years ago. At upper endoscopy, he was found to a have another gastric polyp in his antrum that, on endoscopic ultrasound, appeared to be superficial and not associated with any enlarged lymph nodes. Pathological analysis of the polyp reveals evidence of adenocarcinoma invading into the submucosa. On clinical staging, there is no evidence of distant metastasis. The next step in therapy for this patient is A. repeat endoscopy in 1 year. B. chemotherapy. C. chemoradiotherapy. D. gastric wedge resection. E. subtotal gastrectomy.

Answer: E This patient has an early stage gastric cancer (i.e., no evidence of metastasis or perigastric lymph nodes) on clinical staging and is a candidate for potentially curative resection. Patients with minimal evidence of gastric wall invasion (i.e., mucosal or submucosal invasion) do not require any preoperative therapy and should proceed straight to surgical resection. In this patient with an antral lesion, a subtotal gastrectomy is indicated with frozen section analysis of surgical margins to ensure adequate resection. Wedge resection is not recommended. In patients with evidence of greater gastric wall invasion (i.e., invasion to and beyond the lamina propria), perioperative chemotherapy with epirubicin, cisplatin, and 5-fl uorouracil has been demonstrated to provide a survival benefit. (Malignant Gastric Disease/Adenocarcinoma of the Stomach)

A 40-year-old healthy woman is found to have a serum calcium level of 11 mg/dL during a preventive medicine visit. She is otherwise healthy and takes no medications. There is no family history of endocrine disease. Serum phosphorus is 2.4 mg/dL and PTH level is 90 pg/mL. Sestamibi scan is without focal uptake. Cervical ultrasonography demonstrates a 15-mm ovoid hypoechoic solid soft tissue mass immediately adjacent and lateral to the inferior pole of the right thyroid lobe. Which one of the following is the most appropriate treatment recommendation for this patient? A. Observation and repeat laboratory studies in 6 months B. Begin daily oral furosemide C. Begin saline and bisphosphonates intravenously D. Radioguided parathyroidectomy E. Targeted parathyroidectomy with intraoperative PTH monitoring

Answer: E This patient has early sporadic primary hyperparathyroidism. While she is asymptomatic, she meets the NIH consensus criterion for parathyroid operation of age <50 years. The absence of focal sestamibi uptake precludes radioguided parathyroidectomy since the gamma probe cannot be used to guide the surgeon to the lesion. The sonogram shows a mass consistent with an enlarged right inferior parathyroid gland, so that a targeted approach to parathyroidectomy using ioPTH monitoring is possible. (Primary Hyperparathyroidism/Treatment Surgical)

A 53-year-old woman comes to clinic for evaluation for weight loss. She has recently diagnosed diabetes, asthma, sleep apnea, and hypertension. Her BMI is 38 kg/m2. Which of the following weight loss options is most appropriate for this patient? A. A very low calorie diet B. A low-calorie diet C. Sibutramine D. Orlistat E. Gastric bypass

Answer: E This patient has type II obesity with the life-threatening comorbidity of sleep apnea. As such, she qualifies for surgical intervention according to 1998 NIH guidelines. Weight loss surgery is the only treatment option to demonstrate sustained, substantial weight loss. Gastric bypass, therefore, is indicated. Very low calorie diets are not recommended for weight loss by the NIH guidelines. Although lowcalorie diets, sibutramine, and orlistat are all options in treating obese patients, those individuals who qualify for surgery should undergo it if they are deemed appropriate candidates. (Surgical Treatment of Obesity/Treatment)

A 20-year-old woman is seen in clinic because of a thyroid nodule. She is asymptomatic and her past medical history is unremarkable. She takes no medications. There is a 1-cm firm, solitary, nodule in the lateral aspect of the left lobe of the thyroid. A radionuclide scan showed no uptake of tracer in the nodule. Ultrasonography shows a solid, homogenous 1-cm mass. Fine-needle aspiration cytology shows a follicular neoplasm. What is the next best step in management? A. Irradiation (radioactive iodine) B. Thyroid suppression with thyroxine C. Incisional biopsy and enucleation if benign D. Total thyroidectomy E. Left thyroid lobectomy

Answer: E This patient should undergo a thyroid lobectomy. Even though an FNA showing follicular cells is only 5% likely to be a malignancy, most endocrine surgeons would recommend excision because of that concern. Radioactive iodine is inappropriate because it would destroy normal thyroid and leave the nodule. Suppression with levothyroxine to suppress thyroid-stimulating hormone (TSH) to below normal limits is associated with accelerated osteoporosis and cardiac irregularities. Suppression to within normal range could be a temporizing maneuver. Incisional biopsy and enucleation are inappropriate because neither will allow examination of the interface between the nodule and normal thyroid and potentially not allow the diagnosis of a follicular variant of papillary thyroid carcinoma. Total thyroidectomy is unnecessarily aggressive. (Thyroid Nodule)