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USMLE Step 2 CK study materials
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USMLE Step 2 CK practice questions

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Question 1Internal Medicine

A 62-year-old man presents with 90 minutes of crushing substernal chest pain. ECG shows 3 mm of ST-segment elevation in leads II, III, and aVF. The nearest center capable of percutaneous coronary intervention is 30 minutes away and can accept him immediately. Which of the following is the most appropriate reperfusion strategy?

  1. Symptom-limited exercise stress testing
  2. Immediate intravenous fibrinolytic therapy
  3. Primary percutaneous coronary intervention Correct answer.
  4. Serial troponin measurement before therapy

Explanation

Primary PCI is the preferred reperfusion strategy for STEMI when it can be delivered within 90 minutes of first medical contact, or within 120 minutes when transfer is required. Fibrinolysis is reserved for patients who cannot reach a capable catheterization laboratory within that window and have no contraindication.

Question 2Internal Medicine

A 22-year-old woman with type 1 diabetes presents with vomiting and abdominal pain. Glucose is 480 mg/dL, arterial pH 7.12, bicarbonate 8 mEq/L, and serum ketones are positive. Which of the following should be given first?

  1. Intravenous potassium before fluids
  2. Subcutaneous insulin glargine injection
  3. Intravenous sodium bicarbonate infusion
  4. Intravenous 0.9% saline bolus Correct answer.

Explanation

Diabetic ketoacidosis involves profound total-body volume depletion, so isotonic crystalloid is given first to restore tissue perfusion and begin lowering glucose. An insulin infusion follows, and potassium is replaced once the serum level is known to be low or normal.

Question 3Internal Medicine

A 68-year-old man with a 40-pack-year smoking history reports a chronic productive cough and progressive exertional dyspnea. Post-bronchodilator spirometry shows an FEV1/FVC ratio of 0.62. Which diagnosis best fits these findings?

  1. Diastolic heart failure
  2. Idiopathic pulmonary fibrosis
  3. Bronchiectasis with chronic infection
  4. Chronic obstructive pulmonary disease Correct answer.

Explanation

A post-bronchodilator FEV1/FVC ratio below 0.70 confirms persistent airflow obstruction, and in a smoker with chronic cough and dyspnea this defines COPD. The obstruction is not fully reversible, which distinguishes it from asthma.

Question 4Internal Medicine

A 70-year-old man with chronic kidney disease is found to have a potassium level of 7.2 mEq/L. ECG shows peaked T waves and a widening QRS complex. Which therapy should be administered first?

  1. Intravenous furosemide
  2. Oral sodium polystyrene sulfonate
  3. Insulin with dextrose infusion
  4. Intravenous calcium gluconate Correct answer.

Explanation

Intravenous calcium stabilizes cardiac myocyte membranes and reverses electrocardiographic toxicity within minutes, making it the first drug in hyperkalemia with ECG changes. Potassium-shifting and potassium-removing therapies are given afterward.

Question 5Internal Medicine

A 48-year-old man is found to have hemoglobin 9.8 g/dL, MCV 72 fL, and ferritin 6 ng/mL. He has no bleeding symptoms and takes no aspirin or NSAIDs. Which of the following is the most appropriate next step?

  1. Colonoscopy to identify a bleeding source Correct answer.
  2. Oral iron therapy with repeat testing in one year
  3. Bone marrow biopsy with iron staining
  4. Erythropoietin injections

Explanation

Iron deficiency anemia in an adult man indicates blood loss until proven otherwise, and the gastrointestinal tract is the usual source, so endoscopic evaluation is required. Iron replacement corrects the anemia but does not identify a potentially malignant lesion.

Question 6Internal Medicine

A 34-year-old previously healthy man is diagnosed with community-acquired pneumonia and is stable for outpatient management. He has no chronic lung, liver, or heart disease and has taken no antibiotics in the past 3 months. Which of the following is the most appropriate empiric therapy?

  1. Intravenous vancomycin
  2. Intravenous meropenem
  3. High-dose oral amoxicillin Correct answer.
  4. Oral trimethoprim-sulfamethoxazole

Explanation

Previously healthy outpatients without comorbidities receive empiric coverage for Streptococcus pneumoniae, with high-dose amoxicillin or doxycycline as first-line options. Broader or parenteral regimens are reserved for patients with comorbidities, recent antibiotic exposure, or severe disease.

Question 7Internal Medicine

A 56-year-old woman reports 3 months of heartburn that is controlled with twice-daily omeprazole. She has also developed progressive dysphagia for solid foods and 5 kg of unintentional weight loss. Which of the following is the most appropriate next step?

  1. 24-hour esophageal pH monitoring
  2. Double the proton pump inhibitor dose for 8 weeks
  3. Upper endoscopy Correct answer.
  4. Twice-daily H2 receptor blocker

Explanation

Dysphagia and unintentional weight loss are alarm features that mandate prompt upper endoscopy to exclude esophageal carcinoma and to evaluate for stricture or eosinophilic esophagitis. Empiric acid suppression and pH testing are appropriate only for uncomplicated reflux without alarm features.

Question 8Internal Medicine

A 52-year-old man presents with an acutely painful, swollen, red right first metatarsophalangeal joint. Joint aspiration shows needle-shaped, negatively birefringent crystals. He takes hydrochlorothiazide for hypertension and has normal renal function. Which of the following is the most appropriate immediate management?

  1. No treatment; allow the flare to resolve
  2. Probenecid
  3. Allopurinol alone without anti-inflammatory therapy
  4. Oral naproxen Correct answer.

Explanation

Acute gout is treated with an NSAID, colchicine, or glucocorticoid to abort the inflammatory response. Urate-lowering drugs are not used as sole therapy for a flare because they do not treat the acute inflammation and can prolong the attack.

Question 9Internal Medicine

A 60-year-old man with an ejection fraction of 30% and NYHA class II symptoms is already taking lisinopril and carvedilol. Which additional medication has been shown to reduce mortality in this setting?

  1. Spironolactone Correct answer.
  2. Digoxin, for rate control
  3. Amlodipine, for blood pressure control
  4. Furosemide, for symptom relief

Explanation

Mineralocorticoid receptor antagonists reduce mortality and heart failure hospitalization in patients with reduced ejection fraction who remain symptomatic on an ACE inhibitor and a beta-blocker. Diuretics relieve congestion and digoxin reduces hospitalizations, but neither improves survival.

Question 10Internal Medicine

A 58-year-old woman is 3 days post total hip arthroplasty and develops sudden pleuritic chest pain, tachycardia of 118/min, and hypoxemia. She is normotensive. Pretest probability for pulmonary embolism is high. Which of the following is the most appropriate diagnostic test?

  1. CT pulmonary angiography Correct answer.
  2. Lower extremity compression ultrasonography
  3. Ventilation-perfusion scan
  4. D-dimer assay

Explanation

With a high pretest probability, D-dimer cannot exclude pulmonary embolism and definitive imaging is required, with CT pulmonary angiography as the test of choice. Ventilation-perfusion scanning is reserved for patients who cannot receive iodinated contrast.

Question 11Internal Medicine

A 60-year-old man presents with two episodes of melena, a heart rate of 112/min, and blood pressure of 96/60 mmHg. After intravenous access, crystalloid, and blood transfusion he remains tachycardic but hemodynamically stable. Which of the following is the most appropriate next step?

  1. Emergent exploratory laparotomy now
  2. Oral ferrous sulfate therapy
  3. Barium swallow study
  4. Endoscopy after resuscitation Correct answer.

Explanation

Upper endoscopy is both diagnostic and therapeutic for acute upper gastrointestinal bleeding and should be performed urgently once resuscitation is under way. Endoscopic hemostasis reduces rebleeding, transfusion requirements, and mortality.

Question 12Internal Medicine

A 68-year-old man has nephrotic-range proteinuria. Kidney biopsy shows diffuse thickening of the glomerular basement membrane with subepithelial immune deposits and a spike-and-dome appearance on silver stain. Which diagnosis is most likely?

  1. Focal segmental glomerulosclerosis
  2. Minimal change disease
  3. IgA nephropathy
  4. Membranous nephropathy Correct answer.

Explanation

Subepithelial deposits with basement membrane spikes in a nephrotic adult are the hallmark of membranous nephropathy, which is often associated with anti-phospholipase A2 receptor antibodies. It is the most common cause of nephrotic syndrome in white adults.

Question 13Internal Medicine

A 44-year-old woman has hypertension that persists despite three antihypertensive agents, including a diuretic, and her potassium is 3.1 mEq/L. Which of the following is the most appropriate initial screening test for the likely cause?

  1. 24-hour urinary metanephrines
  2. Overnight dexamethasone suppression test
  3. Aldosterone-to-renin ratio Correct answer.
  4. Renal artery duplex ultrasonography

Explanation

Resistant hypertension with spontaneous hypokalemia suggests primary aldosteronism, which is screened for with the plasma aldosterone concentration to plasma renin activity ratio. Hypokalemia should be corrected before testing for best accuracy.

Question 14Internal Medicine

A 65-year-old woman admitted with pneumonia has received unfractionated heparin for 6 days. Her platelet count falls from 250,000 to 95,000/µL, and she develops a new swollen, painful calf. Which of the following is the most appropriate management?

  1. Start warfarin alone immediately
  2. Continue heparin with platelet monitoring
  3. Transfuse platelets to keep count above 50
  4. Stop heparin and start argatroban Correct answer.

Explanation

A greater than 50% platelet fall 5 to 10 days after heparin exposure with new thrombosis indicates heparin-induced thrombocytopenia, caused by platelet-activating antibodies. Heparin must be stopped immediately and a non-heparin anticoagulant such as argatroban started, because thrombosis rather than bleeding is the major risk.

Question 15Internal Medicine

A 24-year-old college student presents with fever, neck stiffness, and photophobia. CSF shows 2000 white cells/µL with 90% neutrophils, glucose 30 mg/dL, and protein 180 mg/dL. Which of the following empiric regimens is most appropriate?

  1. Ceftriaxone as single therapy
  2. Vancomycin with ceftriaxone Correct answer.
  3. Ampicillin and gentamicin together
  4. Acyclovir as single therapy

Explanation

Empiric therapy for bacterial meningitis in adults combines vancomycin, to cover penicillin-resistant pneumococcus, with a third-generation cephalosporin such as ceftriaxone for meningococcus and susceptible pneumococcus; dexamethasone is given with or before the first antibiotic dose. Ampicillin is added when Listeria is a concern, such as in patients over 50 or immunocompromised patients.

Question 16Internal Medicine

A 72-year-old man with hypertension and type 2 diabetes has newly diagnosed nonvalvular atrial fibrillation. He has no prior stroke and no bleeding history. Which of the following is the most appropriate therapy to reduce stroke risk?

  1. No anticoagulation
  2. Clopidogrel
  3. Apixaban Correct answer.
  4. Aspirin 81 mg daily

Explanation

His CHA2DS2-VASc score is 3 (age 65 to 74, hypertension, diabetes), which clearly warrants oral anticoagulation, and a direct oral anticoagulant such as apixaban is preferred to warfarin in nonvalvular atrial fibrillation. Antiplatelet monotherapy is inadequate for stroke prevention.

Question 17Internal Medicine

A 25-year-old woman with asthma presents with an exacerbation. She speaks in short phrases, and peak expiratory flow is 40% of predicted. After three nebulized albuterol treatments with ipratropium and intravenous methylprednisolone she remains dyspneic with persistent wheezing. Which of the following is the most appropriate addition?

  1. Intravenous magnesium sulfate Correct answer.
  2. Oral theophylline
  3. Prophylactic antibiotics
  4. Chest physiotherapy

Explanation

Intravenous magnesium sulfate is recommended as an adjunct for severe asthma exacerbations that respond poorly to inhaled bronchodilators and systemic corticosteroids, because it relaxes bronchial smooth muscle. It is given alongside continued beta-agonist therapy.

Question 18Internal Medicine

A 45-year-old woman presents with severe epigastric pain radiating to the back, vomiting, and a lipase level 5 times the upper limit of normal. Heart rate is 118/min and blood pressure is 100/65 mmHg. Which of the following is the most appropriate initial intervention?

  1. Prophylactic intravenous antibiotics
  2. Aggressive intravenous fluid resuscitation Correct answer.
  3. Nasogastric suction
  4. Immediate endoscopic retrograde cholangiopancreatography

Explanation

Early aggressive isotonic crystalloid resuscitation, preferably with lactated Ringer's solution, is the cornerstone of initial therapy for acute pancreatitis and reduces pancreatic necrosis and organ failure. ERCP is reserved for concurrent cholangitis or persistent biliary obstruction.

Question 19Internal Medicine

A 70-year-old man with small cell lung cancer has a serum sodium of 122 mEq/L. He is clinically euvolemic. Serum osmolality is 260 mOsm/kg, urine osmolality 520 mOsm/kg, and urine sodium 60 mEq/L. Which of the following is the most appropriate initial therapy?

  1. Isotonic saline infusion
  2. Fluid restriction Correct answer.
  3. Hypertonic saline to raise sodium to 140 mEq/L
  4. Furosemide with free water intake

Explanation

These values indicate SIADH: euvolemic hypotonic hyponatremia with concentrated urine and high urine sodium. Fluid restriction is first-line for mild to moderate cases, with correction limited to roughly 8 to 10 mEq/L in 24 hours to avoid osmotic demyelination.

Question 20Internal Medicine

A 74-year-old woman reports 3 weeks of right temporal headache, scalp tenderness, and jaw pain while chewing. Her ESR is 92 mm/h. Which of the following is the most appropriate next step?

  1. NSAIDs with reassessment in one week
  2. Low-dose oral prednisone
  3. Immediate high-dose glucocorticoids Correct answer.
  4. Temporal artery biopsy before any treatment

Explanation

These features indicate giant cell arteritis, and high-dose glucocorticoids must begin immediately to prevent irreversible visual loss. Temporal artery biopsy should still be obtained, but treatment is never delayed to await it, since the biopsy remains informative for up to 2 weeks after steroids are started.

Question 21Internal Medicine

A 26-year-old male college basketball player has had two syncopal episodes during exertion. Echocardiography shows asymmetric septal hypertrophy with a resting outflow tract gradient. His father died suddenly at age 30. Which of the following is the most appropriate intervention to reduce his risk of sudden cardiac death?

  1. Long-acting verapamil for symptom relief
  2. Implantable cardioverter-defibrillator Correct answer.
  3. Digoxin to improve diastolic filling
  4. Aortic valve replacement surgery

Explanation

Hypertrophic cardiomyopathy with prior exertional syncope and a family history of sudden death places this patient at high risk, and an implantable cardioverter-defibrillator is indicated for secondary and high-risk primary prevention. Verapamil may relieve symptoms but does not reduce arrhythmic death.

Question 22Internal Medicine

A 40-year-old man with known Addison disease presents with 2 days of vomiting, blood pressure 78/50 mmHg, sodium 128 mEq/L, potassium 5.6 mEq/L, and glucose 58 mg/dL. Which of the following is the most appropriate immediate therapy?

  1. Insulin with dextrose infusion
  2. Fludrocortisone alone
  3. Oral prednisone and outpatient follow-up
  4. IV hydrocortisone plus saline Correct answer.

Explanation

This is an adrenal crisis, which requires immediate parenteral hydrocortisone together with isotonic saline for volume and glucose support, without waiting for confirmatory testing. Hydrocortisone at stress doses provides both glucocorticoid and mineralocorticoid activity, so fludrocortisone is not needed acutely.

Question 23Internal Medicine

A 24-year-old man with newly diagnosed Burkitt lymphoma began chemotherapy 48 hours ago. He is oliguric. Laboratory studies show potassium 6.4 mEq/L, phosphate 7.5 mg/dL, calcium 7.2 mg/dL, uric acid 13 mg/dL, and creatinine 2.4 mg/dL. Which of the following is the most appropriate initial therapy?

  1. Furosemide alone to increase urine output
  2. Intravenous hydration with rasburicase Correct answer.
  3. Potassium replacement therapy
  4. Calcium replacement for hypocalcemia

Explanation

These findings define tumor lysis syndrome, and management centers on vigorous intravenous hydration plus a urate oxidase such as rasburicase for the marked hyperuricemia. Calcium is given only for symptomatic hypocalcemia, because precipitation of calcium phosphate can worsen tissue injury.

Question 24Internal Medicine

A 32-year-old man is brought in after a building collapse with prolonged immobilization of both legs. He is tachycardic with blood pressure 98/60 mmHg, and his urine is dark brown. Creatine kinase is 62,000 U/L and creatinine is 1.9 mg/dL. Which of the following is the most appropriate initial management?

  1. Loop diuretics to maintain high urine output
  2. Sodium bicarbonate for all patients
  3. Fluid restriction to prevent pulmonary edema
  4. Aggressive isotonic fluid resuscitation Correct answer.

Explanation

Rhabdomyolysis releases myoglobin that obstructs tubules and causes acute kidney injury, so early aggressive isotonic crystalloid to maintain brisk urine output is the mainstay of prevention. Bicarbonate and mannitol are optional adjuncts without proven benefit, and potassium must be monitored closely.

Question 25Internal Medicine

A 55-year-old man with alcohol-related cirrhosis and ascites presents with fever and diffuse abdominal pain. Diagnostic paracentesis shows 480 polymorphonuclear cells/µL and a single organism on Gram stain. Which of the following is the most appropriate initial therapy?

  1. Oral ciprofloxacin alone
  2. IV cefotaxime plus albumin Correct answer.
  3. Therapeutic paracentesis alone
  4. Escalation of diuretic therapy

Explanation

An ascitic neutrophil count of 250/µL or more establishes spontaneous bacterial peritonitis, which is treated with a third-generation cephalosporin such as cefotaxime. Adding intravenous albumin on day 1 and day 3 reduces the incidence of hepatorenal syndrome and mortality in high-risk patients.

Question 26Internal Medicine

A 28-year-old woman presents with 3 months of fatigue and heavy menstrual bleeding. Hemoglobin is 9.6 g/dL, MCV is 72 fL, and ferritin is 6 ng/mL. Which of the following is the most appropriate initial treatment?

  1. Oral ferrous sulfate Correct answer.
  2. Intravenous iron sucrose
  3. Packed red blood cell transfusion
  4. Subcutaneous erythropoietin

Explanation

Iron deficiency anemia due to chronic menstrual blood loss is treated first with oral iron; a ferritin of 6 ng/mL confirms depleted iron stores. Transfusion is reserved for hemodynamic instability or severe symptomatic anemia, and IV iron is for malabsorption, intolerance, or inadequate oral response. Erythropoietin is not indicated in iron deficiency without chronic kidney disease.

Question 27Internal Medicine

A 62-year-old man with stage 4 chronic kidney disease presents with weakness. Serum potassium is 6.9 mEq/L. ECG shows peaked T waves and a widened QRS complex. Which of the following is the most appropriate immediate treatment?

  1. Nebulized albuterol
  2. Subcutaneous insulin with dextrose
  3. Intravenous calcium gluconate Correct answer.
  4. Oral sodium polystyrene sulfonate

Explanation

Hyperkalemia with ECG changes such as peaked T waves and a widened QRS requires immediate intravenous calcium to stabilize the myocardial membrane. Calcium does not lower serum potassium; insulin with dextrose, albuterol, and potassium binders are used afterward to shift or remove potassium.

Question 28Internal Medicine

A 24-year-old man with type 1 diabetes presents with vomiting and Kussmaul respirations. Glucose is 480 mg/dL, pH is 7.12, bicarbonate is 8 mEq/L, and serum potassium is 4.8 mEq/L. After initial intravenous fluids, which of the following is the most appropriate next step?

  1. Give potassium before starting insulin
  2. Start an intravenous insulin infusion Correct answer.
  3. Give subcutaneous insulin glargine alone
  4. Administer intravenous sodium bicarbonate

Explanation

In DKA, an insulin infusion is started after volume resuscitation when potassium is at least 3.3 mEq/L; this patient’s potassium of 4.8 mEq/L is adequate. Potassium is added to fluids when serum potassium is below 5.2 mEq/L, and bicarbonate is not routinely given.

Question 29Internal Medicine

A 68-year-old man with chronic obstructive pulmonary disease presents with 2 days of increased dyspnea and purulent sputum. Respiratory rate is 28/min, and oxygen saturation is 86% on room air. Which of the following is the most appropriate oxygen strategy?

  1. Titrate oxygen to a saturation of 88% to 92% Correct answer.
  2. No supplemental oxygen unless he becomes unresponsive
  3. Target oxygen saturation of 94% to 98%
  4. High-flow oxygen by nonrebreather mask to 100%

Explanation

In an acute COPD exacerbation with hypoxemia, supplemental oxygen should be titrated to an SpO2 of 88% to 92% to reduce the risk of hyperoxia-related worsening ventilation-perfusion mismatch. Higher targets are used in most other acute medical conditions but not routinely in COPD.

Question 30Internal Medicine

A 32-year-old woman presents with 6 months of weight loss, heat intolerance, tremor, and palpitations. TSH is suppressed, free T4 is elevated, and she has a diffuse goiter. She prefers to avoid radioactive iodine and surgery. Which of the following is the most appropriate initial pharmacologic therapy?

  1. Levothyroxine
  2. Propranolol alone
  3. Methimazole Correct answer.
  4. Radioactive iodine

Explanation

Graves disease is treated with a thionamide such as methimazole when the patient wants to avoid radioactive iodine and surgery. Beta-blockers relieve tremor and palpitations but do not treat the underlying hyperthyroidism.

Question 31Internal Medicine

A 41-year-old man who injects drugs presents with fever, a tricuspid murmur, and multiple pulmonary nodules. Blood cultures grow methicillin-susceptible Staphylococcus aureus. Which of the following is the most appropriate antibiotic therapy for native tricuspid valve endocarditis?

  1. Nafcillin Correct answer.
  2. Daptomycin
  3. Ceftriaxone
  4. Vancomycin

Explanation

Native-valve endocarditis caused by methicillin-susceptible S. aureus is treated with an antistaphylococcal penicillin such as nafcillin for 6 weeks. Vancomycin is used for MRSA or severe penicillin allergy, and daptomycin is generally an alternative rather than first-line therapy.

Question 32Internal Medicine

A 64-year-old woman with squamous cell carcinoma of the lung presents with confusion and constipation. Serum calcium is 14.2 mg/dL, creatinine is 1.0 mg/dL, and she is hemodynamically stable. Which of the following is the most appropriate initial therapy?

  1. Oral calcium carbonate
  2. Isotonic saline infusion Correct answer.
  3. Subcutaneous calcitonin alone
  4. Intravenous furosemide alone

Explanation

Symptomatic hypercalcemia of malignancy is initially managed with aggressive volume repletion using isotonic saline, followed by a bisphosphonate. Calcitonin can be added for rapid effect, but it is not used alone; loop diuretics are avoided until volume status is corrected.

Question 33Internal Medicine

A 72-year-old woman develops 6 watery stools per day after 5 days of clindamycin for a dental infection. Stool testing is positive for Clostridioides difficile toxin. Which of the following is the most appropriate initial treatment?

  1. Loperamide
  2. Oral metronidazole
  3. Intravenous vancomycin
  4. Oral vancomycin Correct answer.

Explanation

Initial Clostridioides difficile infection is treated with oral vancomycin or fidaxomicin; oral vancomycin is the best choice among these options. Intravenous vancomycin does not reach the colonic lumen, and antimotility agents can precipitate ileus or toxic megacolon.

Question 34Internal Medicine

A 58-year-old man is brought to the emergency department 45 minutes after sudden onset of right-sided weakness and inability to speak. Blood pressure is 186/108 mmHg, glucose is 118 mg/dL, and noncontrast head CT shows no hemorrhage. Which of the following is the most appropriate next step?

  1. Start a therapeutic heparin infusion now
  2. Give alteplase immediately without treating blood pressure
  3. Lower blood pressure below 185/110 mmHg, then give alteplase Correct answer.
  4. Give aspirin 325 mg immediately without thrombolysis

Explanation

This patient has an acute ischemic stroke within the thrombolytic window. Intravenous alteplase can be given only after blood pressure is lowered below 185/110 mmHg; aspirin is typically delayed for 24 hours after thrombolysis, and heparin is not used acutely.

Question 35Surgery

A 24-year-old man presents with 14 hours of periumbilical pain that has migrated to the right lower quadrant, along with anorexia and a temperature of 38.0 °C. Examination shows rebound tenderness at McBurney point. He is hemodynamically stable and has no signs of generalized peritonitis.

  1. Observation with serial abdominal examinations
  2. Intravenous antibiotics with reassessment in 24 hours
  3. Laparoscopic appendectomy Correct answer.
  4. Colonoscopy to exclude a cecal tumor

Explanation

Acute appendicitis in a stable patient without perforation or abscess is treated with prompt appendectomy, which is definitive and prevents progression to perforation. Antibiotic-only strategies carry substantially higher recurrence and failure rates and are reserved for selected patients who cannot undergo surgery.

Question 36Surgery

A 46-year-old woman presents with 10 hours of constant right upper quadrant pain radiating to the right scapula, nausea, and a temperature of 38.3 °C. She has right upper quadrant tenderness with a positive Murphy sign, leukocytosis, and a mildly elevated alkaline phosphatase.

  1. Cholescintigraphy with hepatobiliary iminodiacetic acid tracer
  2. Abdominal computed tomography with contrast
  3. Magnetic resonance cholangiopancreatography
  4. Right upper quadrant ultrasonography Correct answer.

Explanation

Right upper quadrant ultrasonography is the preferred initial study for suspected acute cholecystitis, detecting stones, wall thickening, pericholecystic fluid, and a sonographic Murphy sign. Cholescintigraphy is reserved for cases in which ultrasound is equivocal.

Question 37Surgery

A 58-year-old man presents with a 6-month history of a reducible, mildly uncomfortable right groin bulge that worsens with coughing. He has no signs of incarceration or strangulation and is otherwise healthy.

  1. Application of an external supportive truss device
  2. Elective tension-free mesh herniorrhaphy Correct answer.
  3. Emergent groin exploration
  4. Reassurance without surgical referral

Explanation

Symptomatic inguinal hernias in acceptable surgical candidates should be repaired electively to relieve symptoms and prevent incarceration. A tension-free mesh repair is the standard operation for a primary unilateral inguinal hernia.

Question 38Surgery

A 32-year-old man is brought to the emergency department after a high-speed motorcycle collision. He is agitated, with blood pressure 88/60 mmHg and heart rate 132/min. He has a distended abdomen, gurgling respirations, and active facial bleeding.

  1. Needle decompression of the left chest
  2. Focused assessment with sonography for trauma
  3. Airway control with cervical spine protection Correct answer.
  4. Rapid infusion of packed red blood cells

Explanation

The primary survey follows the ABCDE sequence, and airway with cervical spine protection always comes first; gurgling respirations and facial bleeding indicate airway compromise requiring immediate control. Hemorrhage control and circulation management follow assessment of breathing.

Question 39Surgery

A 41-year-old woman is found to have a solitary 2.0 cm solid thyroid nodule. She is euthyroid with a normal TSH. Ultrasonography shows a hypoechoic nodule with irregular margins and no cervical lymphadenopathy.

  1. Fine-needle aspiration biopsy Correct answer.
  2. Repeat ultrasonography in 12 months
  3. Total thyroidectomy
  4. Serum thyroglobulin measurement

Explanation

Nodules 1 cm or larger with suspicious sonographic features such as hypoechogenicity and irregular margins warrant fine-needle aspiration to assess for malignancy. Sonographic surveillance is appropriate only for low-suspicion nodules below the biopsy threshold.

Question 40Surgery

A 52-year-old asymptomatic man with no family history of colorectal cancer and no other risk factors presents for a routine health maintenance visit.

  1. Colonoscopy every 10 years Correct answer.
  2. Serum CEA every 2 years
  3. Colonoscopy every 3 years
  4. Fecal occult blood testing every 5 years

Explanation

Average-risk adults begin colorectal cancer screening at age 45, and colonoscopy every 10 years is a first-line strategy. Annual stool-based testing and flexible sigmoidoscopy every 5 years are acceptable alternatives.

Question 41Surgery

A 14-year-old boy presents with 2 hours of sudden severe left scrotal pain, nausea, and vomiting. The left testis is high-riding and transversely oriented, and the cremasteric reflex is absent.

  1. Elevation and application of ice packs
  2. Empiric antibiotics for epididymitis
  3. Immediate surgical exploration Correct answer.
  4. Scrotal ultrasonography with Doppler flow

Explanation

Testicular torsion is a clinical diagnosis and a surgical emergency; detorsion with bilateral orchiopexy within roughly 6 hours of symptom onset preserves viability in most cases. Imaging is appropriate only when the presentation is equivocal and must never delay exploration.

Question 42Surgery

A 60-year-old man undergoes an elective sigmoid colectomy with primary anastomosis for diverticular disease. The bowel was mechanically prepped, and no gross spillage occurred during the operation.

  1. Clean-contaminated Correct answer.
  2. Contaminated
  3. Dirty
  4. Clean

Explanation

Clean-contaminated wounds are those in which a hollow viscus is entered under controlled conditions without unusual contamination, as in an elective prepped colectomy. This classification predicts the expected wound infection rate and guides perioperative antibiotic prophylaxis.

Question 43Surgery

A 66-year-old woman presents with 2 days of crampy abdominal pain, vomiting, and distension. She had an open hysterectomy 10 years ago. Heart rate is 104/min and blood pressure 108/70 mmHg. The abdomen is distended and tympanitic with high-pitched bowel sounds. Abdominal radiographs show dilated small bowel loops with air-fluid levels and no colonic gas.

  1. Oral intake and ambulation
  2. Immediate exploratory laparotomy with bowel resection
  3. Intravenous fluids and nasogastric decompression Correct answer.
  4. Water-soluble contrast study with serial examinations

Explanation

Uncomplicated adhesive small bowel obstruction is initially managed with intravenous fluid and electrolyte resuscitation plus nasogastric decompression, and most cases resolve within 24 to 72 hours. Operative intervention is reserved for strangulation, perforation, closed-loop obstruction, or failure of nonoperative therapy.

Question 44Surgery

A 70-kg man sustains partial- and full-thickness burns over 40% of his total body surface area in a house fire. He arrives at the emergency department 2 hours after the injury.

  1. 11,200 mL
  2. 5,600 mL Correct answer.
  3. 4,200 mL
  4. 2,800 mL

Explanation

The Parkland formula gives 4 mL/kg per percent total body surface area over 24 hours, which is 11,200 mL here; half of that volume is administered in the first 8 hours from the time of injury. The remaining half is given over the subsequent 16 hours.

Question 45Surgery

A 28-year-old man is brought in after a fall from height. He is anxious and confused. Heart rate is 130/min, blood pressure 86/70 mmHg, respiratory rate 28/min, and urine output is 20 mL/h. He has a distended abdomen and a positive FAST examination.

  1. 500 to 750 mL
  2. 750 to 1500 mL
  3. 1500 to 2000 mL Correct answer.
  4. More than 2000 mL

Explanation

Class III hemorrhagic shock corresponds to 30 to 40 percent blood loss, roughly 1500 to 2000 mL in a 70-kg adult, and is characterized by tachycardia, hypotension with narrowed pulse pressure, oliguria, and confusion. Class IV hemorrhage exceeds 40 percent and produces marked lethargy with negligible urine output.

Question 46Surgery

A 38-year-old woman undergoes total thyroidectomy with central neck dissection for papillary thyroid carcinoma. Eighteen hours postoperatively she reports perioral and fingertip tingling, and a Chvostek sign is elicited.

  1. Urgent neck exploration for hematoma
  2. Oral levothyroxine replacement
  3. Intravenous calcium gluconate Correct answer.
  4. Oral calcium carbonate with vitamin D

Explanation

Symptomatic hypocalcemia from transient parathyroid ischemia after total thyroidectomy is treated with intravenous calcium to prevent tetany, seizures, and laryngospasm. Oral calcium and activated vitamin D are added once the patient is stabilized and for maintenance.

Question 47Surgery

A 54-year-old woman has a 1.8 cm invasive ductal carcinoma in the upper outer quadrant of the left breast. Clinical examination and axillary ultrasonography reveal no suspicious lymph nodes.

  1. Complete axillary lymph node dissection
  2. Fine-needle aspiration of the axilla
  3. Sentinel lymph node biopsy Correct answer.
  4. Observation of the axilla without staging

Explanation

Sentinel lymph node biopsy is the standard axillary staging procedure for clinically node-negative early breast cancer, offering accuracy comparable to dissection with far less lymphedema and nerve injury. Completion axillary dissection is reserved for clinically node-positive disease or selected patients with positive sentinel nodes.

Question 48Surgery

A 62-year-old man presents with 4 days of left lower quadrant pain, fever of 38.6 °C, and leukocytosis. Computed tomography shows sigmoid diverticulitis with a 4-cm pericolic fluid collection containing gas.

  1. Emergent sigmoid colectomy with end colostomy
  2. Intravenous antibiotics alone
  3. Percutaneous drainage with antibiotics Correct answer.
  4. Oral antibiotics and outpatient follow-up

Explanation

Diverticular abscesses of 3 to 4 cm or larger are best managed with image-guided percutaneous drainage plus intravenous antibiotics, which achieves source control and permits elective resection later if indicated. Abscesses smaller than 3 cm often respond to antibiotics alone.

Question 49Surgery

A 58-year-old man with poorly controlled diabetes presents with 2 days of rapidly spreading pain and swelling of the right thigh. Temperature is 39.1 °C, heart rate 126/min, and blood pressure 88/54 mmHg. The skin is dusky with bullae, crepitus is palpable, and pain is out of proportion to the examination.

  1. Intravenous antibiotics and ICU observation
  2. Urgent MRI to confirm the diagnosis
  3. Hyperbaric oxygen therapy as primary treatment
  4. Immediate surgical debridement and antibiotics Correct answer.

Explanation

Necrotizing fasciitis is a surgical emergency in which survival depends on early, aggressive debridement of all necrotic tissue combined with broad-spectrum antibiotics and hemodynamic support. Imaging may support the diagnosis but must never delay operative exploration when the clinical picture is typical.

Question 50Surgery

A 25-year-old man falls from a bicycle and has left upper quadrant tenderness. Blood pressure is 122/78 mmHg, heart rate 96/min, and hemoglobin is 12.4 g/dL. Contrast computed tomography shows a grade III splenic laceration with a small amount of perisplenic fluid and no active contrast extravasation.

  1. Nonoperative management with monitoring Correct answer.
  2. Diagnostic peritoneal lavage
  3. Angioembolization in all splenic injuries
  4. Immediate splenectomy

Explanation

Hemodynamically stable patients with blunt splenic injury and no active contrast extravasation are managed nonoperatively with bed rest, serial abdominal examinations, and hemoglobin monitoring. Splenic artery embolization is added for active extravasation, pseudoaneurysm, or higher-grade injuries.