USMLE Step 3 Quiz: Postoperative And Post Trauma Care
20 questions · exam conditions
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Postoperative And Post Trauma CareQuestion 1 of 20

Crush injury, brown urine, potassium 6.1, peaked T waves. Best first step?

IV normal saline bolus
IV calcium gluconate
IV sodium bicarbonate
IV insulin and glucose
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USMLE Step 3 Quiz

USMLE Step 3 Quiz: Postoperative And Post Trauma Care

Practice Postoperative And Post Trauma Care in USMLE Step 3 with focused quiz questions that help you check what you know, review explanations, and build confidence with test-style prompts.

What this quiz covers

This quiz focuses on Postoperative And Post Trauma Care, giving you a quick way to practice the rules, question types, and explanations that matter most for USMLE Step 3.

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

All questions

Question 1

Crush injury, brown urine, potassium 6.1, peaked T waves. Best first step?

  1. IV normal saline bolus
  2. IV calcium gluconate (correct answer)
  3. IV sodium bicarbonate
  4. IV insulin and glucose
Explanation: Peaked T waves with potassium 6.1 mean hyperkalemia is causing cardiac membrane instability, so the first step is IV calcium gluconate to stabilize the myocardium. IV insulin and glucose is tempting because it lowers potassium, but it acts too slowly to protect the heart from arrhythmia. IV sodium bicarbonate also lowers potassium gradually, and IV saline treats volume depletion but not the immediate cardiac risk.

Question 2

Postop day 2 after colectomy: temp 38.6, HR 100, lungs clear. Best initial?

  1. Blood and urine cultures
  2. CT abdomen with contrast
  3. IV broad-spectrum antibiotics
  4. Encourage early ambulation (correct answer)
Explanation: Fever on postoperative day 2 with clear lungs and only mild tachycardia is classically atelectasis, so first step is early ambulation and incentive spirometry. This improves ventilation and often resolves the fever. Blood and urine cultures are tempting but not initial unless the patient has signs of infection; broad-spectrum antibiotics and CT abdomen are reserved for suspected leak or sepsis, not routine early postoperative fever.

Question 3

Elderly patient, postop day 1 after hip arthroplasty, agitated, pulling at IV. First-line?

  1. Nonpharmacologic care (correct answer)
  2. IV haloperidol 2 mg
  3. Soft wrist restraints
  4. Lorazepam 1 mg IV push
Explanation: In postoperative delirium, your first move is supportive care: reorient, remove the IV source, involve family, and protect sleep. Haloperidol is the most tempting choice for acute agitation, but medications are reserved only after nonpharmacologic measures fail or the patient is unsafe. Lorazepam can worsen delirium in older adults and restraints are not first-line.

Question 4

Hematoma after thyroidectomy: stridor, expanding neck. Immediate?

  1. Awake fiberoptic intubation
  2. Observe and apply cold pack
  3. Open incision at bedside (correct answer)
  4. Return to operating room
Explanation: Expanding neck hematoma after thyroidectomy with stridor means tracheal compression and impending airway loss. You must open the incision at bedside immediately to evacuate the clot and decompress the airway. Returning to the operating room is tempting but delays lifesaving decompression; intubating first can fail because anatomy is distorted. Definitive hemostasis follows once the airway is secured.

Question 5

Blunt trauma, damage-control laparotomy; 12 h later bladder pressure 22 mm Hg, urine 10 mL/h, peak airway 35. Best next?

  1. Surgical decompression (correct answer)
  2. Rapid isotonic fluid bolus
  3. Norepinephrine infusion
  4. CT of abdomen and pelvis
Explanation: A bladder pressure of 22 mm Hg with oliguria and high peak airway pressure after laparotomy indicates abdominal compartment syndrome. The source is intra-abdominal pressure, so fluid or vasopressors only mask the problem while organ injury worsens. Immediate decompressive laparotomy is required. The most tempting wrong choice is an isotonic fluid bolus, but it can increase bowel edema and raise intra-abdominal pressure further.

Question 6

A 50-year-old man has been in the ICU for two weeks recovering from severe thermal burns covering 40% of his body surface area. He has been receiving total parenteral nutrition (TPN) for the past 12 days. He develops a new fever to 39.0°C (102.2°F), right upper quadrant tenderness, and a white blood cell count of 16,000/mm³. An abdominal ultrasound shows a distended gallbladder with a thickened wall (>4 mm) and pericholecystic fluid, but no gallstones are visualized.

  1. Ascending cholangitis.
  2. TPN-induced cholestasis.
  3. Acute pancreatitis.
  4. Acute acalculous cholecystitis. (correct answer)
Explanation: When you encounter a critically ill patient with gallbladder symptoms but no stones on imaging, think acute acalculous cholecystitis (AAC). This condition typically affects patients with severe illness, prolonged fasting, or TPN use—exactly what we see here. This patient's presentation perfectly fits AAC: he's critically ill with severe burns, has been on prolonged TPN (12 days), and shows the classic triad of fever, right upper quadrant pain, and leukocytosis. The ultrasound findings of gallbladder wall thickening >4mm, distension, and pericholecystic fluid without stones clinch the diagnosis. AAC occurs because critical illness and prolonged fasting lead to gallbladder stasis and ischemia, causing inflammation without obstruction. Looking at the wrong answers: (A) Ascending cholangitis would present with Charcot's triad (fever, jaundice, RUQ pain) and typically requires biliary obstruction—you'd expect dilated bile ducts on imaging. (B) TPN-induced cholestasis causes jaundice and elevated bilirubin rather than acute inflammatory symptoms with normal bile ducts. (C) Acute pancreatitis would cause epigastric pain radiating to the back with elevated lipase/amylase, not the focused RUQ tenderness and gallbladder changes seen here. For USMLE Step 3, remember that AAC is a high-yield diagnosis in ICU patients. Key associations include major surgery, burns, sepsis, prolonged fasting, and TPN use. Unlike calculous cholecystitis, stones are absent, but the inflammatory findings on imaging are the same. Early recognition is crucial since AAC can rapidly progress to perforation.

Question 7

A 35-year-old woman who underwent a Roux-en-Y gastric bypass 3 years ago presents to the emergency department with a 12-hour history of severe, cramping, periumbilical abdominal pain and non-bilious vomiting. On examination, she is tachycardic to 120/min and has diffuse abdominal tenderness without peritoneal signs. A plain abdominal x-ray is unremarkable.

  1. Internal hernia with small bowel obstruction. (correct answer)
  2. Marginal ulcer at the gastrojejunostomy.
  3. Gastric dumping syndrome.
  4. Acute calculous cholecystitis.
Explanation: When you encounter post-bariatric surgery patients with acute abdominal pain, think systematically about the unique complications these procedures create. Roux-en-Y gastric bypass creates several potential spaces where bowel can become trapped, making internal hernias a significant long-term risk. This patient's presentation strongly suggests internal hernia with small bowel obstruction. The severe, cramping periumbilical pain with non-bilious vomiting is classic for small bowel obstruction. The tachycardia indicates physiologic stress, while the absence of peritoneal signs suggests obstruction without perforation. Crucially, plain abdominal x-rays are often normal in early small bowel obstruction, especially when caused by internal hernias where bowel loops can appear deceptively normal on plain films. Option B, marginal ulcer at the gastrojejunostomy, typically presents with epigastric pain, often related to eating, and may cause hematemesis or melena rather than this obstruction pattern. Option C, gastric dumping syndrome, occurs shortly after eating and involves cramping with diarrhea, sweating, and palpitations - not the sustained severe pain described here. Option D, acute calculous cholecystitis, would cause right upper quadrant pain with possible Murphy's sign, not periumbilical cramping. For Step 3, remember that internal hernias are the most common cause of bowel obstruction in post-Roux-en-Y patients, often presenting months to years after surgery. When plain films are unremarkable but clinical suspicion is high, CT scan is the next step. Don't be fooled by normal plain films in suspected small bowel obstruction.

Question 8

A 28-year-old man is 12 hours postoperative from an intramedullary nail fixation of a right tibial shaft fracture. He is using a patient-controlled analgesia (PCA) pump with morphine. The nurse calls to report that his pain is progressively worsening and is not relieved by additional PCA doses. On examination, the patient's lower leg is tense and exquisitely tender. He reports numbness between his first and second toes. Pain is dramatically increased with passive dorsiflexion of the toes.

  1. Increase the demand dose on the PCA pump.
  2. Obtain an urgent X-ray of the tibia and fibula.
  3. Administer an intravenous bolus of ketorolac.
  4. Immediately notify the orthopedic surgeon for possible fasciotomy. (correct answer)
Explanation: When you encounter progressive, severe post-operative pain in an extremity that's unresponsive to opioids, think compartment syndrome—a surgical emergency requiring immediate recognition and intervention. This patient presents classic signs of compartment syndrome: progressively worsening pain despite adequate analgesia, tense and tender lower leg, numbness in the first web space (deep peroneal nerve distribution), and severe pain with passive toe dorsiflexion. The mechanism involves increased pressure within fascial compartments that compromises circulation and nerve function. Tibial fractures, especially with intramedullary nailing, carry significant compartment syndrome risk due to bleeding and swelling in tight fascial spaces. Option D is correct because compartment syndrome requires emergency fasciotomy to relieve pressure and prevent permanent damage to muscles, nerves, and potentially limb loss. Every hour of delay increases morbidity. Option A is wrong because increasing morphine won't address the underlying pathophysiology and may mask important clinical signs. Pain from compartment syndrome is characteristically severe and opioid-resistant. Option B wastes critical time. While hardware complications exist, the clinical picture clearly suggests compartment syndrome, not implant failure. Option C is incorrect because ketorolac, though helpful for post-operative pain, cannot relieve compartment syndrome. NSAIDs may also increase bleeding risk in this setting. Study tip: Remember the "5 P's" of compartment syndrome: Pain (especially with passive stretch), Pressure, Pallor, Paresthesias, and Pulselessness. However, don't wait for all signs—severe pain with passive stretch is the earliest and most reliable indicator requiring immediate surgical consultation.

Question 9

A 70-year-old man with a history of benign prostatic hyperplasia is in the post-anesthesia care unit 6 hours after an inguinal hernia repair performed under spinal anesthesia. He complains of significant suprapubic discomfort and has an urgent desire to void but is unable to do so. A bladder scan shows 700 mL of urine.

  1. Administer a single oral dose of tamsulosin.
  2. Encourage ambulation and increased oral fluid intake.
  3. Insert an indwelling Foley catheter to be left in for 3 days.
  4. Perform a one-time, in-and-out bladder catheterization. (correct answer)
Explanation: When you encounter postoperative urinary retention, especially after spinal anesthesia in elderly men with BPH, you're dealing with a common but urgent complication that requires immediate relief to prevent bladder injury and patient discomfort. This patient has classic acute urinary retention with 700 mL in his bladder (normal capacity is 300-500 mL) and inability to void despite strong urge. The combination of spinal anesthesia (which temporarily impairs bladder function), his age, BPH history, and recent surgery creates the perfect storm for retention. Option D is correct because immediate bladder decompression is essential. A one-time, in-and-out catheterization provides instant relief without the infection risks of an indwelling catheter. Many patients regain normal voiding function once the spinal anesthesia completely wears off. Option A (tamsulosin) won't work fast enough - alpha-blockers take days to weeks for full effect, and this patient needs immediate relief. Option B (ambulation and fluids) is counterproductive - adding more fluid to an already overdistended bladder worsens the situation, and walking won't overcome the mechanical/neurological obstruction. Option C (indwelling Foley for 3 days) is unnecessarily invasive for what might be temporary retention; it significantly increases infection risk and isn't the first-line approach. For Step 3, remember that urinary retention with volumes >500-600 mL requires immediate catheterization. Always try the least invasive effective intervention first - straight catheterization before indwelling catheters unless multiple attempts are expected.

Question 10

A 68-year-old man is on postoperative day 5 following a sigmoid colectomy for complicated diverticulitis. He develops a fever of 39.1°C (102.4°F), a heart rate of 115/min, and complains of new-onset, localized pain in the left lower quadrant. His white blood cell count is 18,000/mm³. The surgical incision appears clean and without drainage. Chest x-ray is clear.

  1. Obtain blood cultures and start empiric broad-spectrum antibiotics.
  2. Perform a CT scan of the abdomen and pelvis with oral and IV contrast. (correct answer)
  3. Administer aggressive incentive spirometry and chest physiotherapy.
  4. Request an urgent surgical consultation for exploratory laparotomy.
Explanation: The patient's presentation on postoperative day 5 with fever, tachycardia, localized abdominal pain, and leukocytosis is highly concerning for an intra-abdominal abscess or an anastomotic leak. A CT scan of the abdomen and pelvis with contrast is the most appropriate next step to confirm the diagnosis and guide further management, such as percutaneous drainage or surgical intervention. While antibiotics are necessary, they should be initiated after or concurrently with imaging to identify the source. Incentive spirometry targets atelectasis, which typically presents earlier (POD 1-2). Exploratory laparotomy is premature without first confirming the diagnosis with imaging.

Question 11

A 55-year-old woman is on postoperative day 4 following an open total abdominal hysterectomy. She reports persistent nausea, has had several episodes of bilious vomiting, and has not passed flatus since the surgery. Her abdomen is distended and tympanitic. Bowel sounds are absent.

  1. Diffusely dilated loops of both small and large bowel on abdominal x-ray.
  2. A clear transition point with dilated proximal bowel and decompressed distal bowel on CT scan. (correct answer)
  3. A serum potassium level of 3.2 mEq/L on laboratory testing.
  4. Passage of a small amount of watery stool after a suppository.
Explanation: Differentiating prolonged postoperative ileus from an early mechanical small bowel obstruction is critical. While both can present with nausea, vomiting, and distention, the key feature of a mechanical obstruction is a discrete point of blockage. A CT scan showing a transition point with proximal dilation and distal collapse is the hallmark of mechanical obstruction. In contrast, ileus is characterized by generalized hypomotility of the entire gastrointestinal tract, which appears as diffusely dilated loops of both small and large bowel on imaging. Hypokalemia can cause or worsen an ileus but is not specific for obstruction.

Question 12

A 78-year-old man is on postoperative day 2 following a right hemicolectomy for colon cancer. He develops new-onset atrial fibrillation with a heart rate of 145/min. His blood pressure is 105/65 mmHg. He is awake, alert, and denies chest pain or shortness of breath. An ECG confirms atrial fibrillation with a rapid ventricular response.

  1. Synchronized electrical cardioversion.
  2. An intravenous bolus of amiodarone.
  3. An intravenous bolus of metoprolol. (correct answer)
  4. An oral loading dose of digoxin.
Explanation: The patient has new-onset postoperative atrial fibrillation with a rapid ventricular response but is hemodynamically stable. The primary goal is rate control. Intravenous beta-blockers (e.g., metoprolol) or non-dihydropyridine calcium channel blockers (e.g., diltiazem) are the first-line agents for acute rate control in this setting. Synchronized cardioversion is reserved for hemodynamically unstable patients. Amiodarone is typically a second-line agent for rate control or can be used for rhythm control. Digoxin has a slow onset of action and is not ideal for acute management.

Question 13

A 22-year-old woman is seen for follow-up 6 weeks after hospital discharge for a pelvic fracture sustained in a severe motor vehicle accident. She reports intrusive memories of the crash, persistent nightmares, and avoids getting into cars. She states she feels detached from her friends and family and is constantly 'on edge.' These symptoms are causing significant distress and impairing her ability to return to work.

  1. Reassure her that this is a normal stress response that will resolve with time.
  2. Prescribe a short-term course of alprazolam to use as needed for anxiety.
  3. Recommend she begin a graded exposure program by sitting in a parked car daily.
  4. Refer her to a mental health professional for trauma-focused psychotherapy. (correct answer)
Explanation: When you encounter a patient presenting with trauma-related symptoms following a significant event, you need to systematically assess the duration, severity, and functional impact to distinguish between normal stress responses and clinical disorders like PTSD. This patient presents with classic PTSD symptoms occurring 6 weeks post-trauma: intrusive memories (re-experiencing), nightmares, avoidance behaviors (won't get in cars), emotional numbing (detachment from others), and hypervigilance ("on edge"). Crucially, these symptoms are causing significant functional impairment (can't return to work) and have persisted beyond the typical acute stress response timeframe. PTSD requires specialized trauma-focused psychotherapy as first-line treatment, making referral to a mental health professional (D) the most appropriate intervention. Option A is incorrect because while some initial stress response is normal, symptoms persisting 6 weeks with functional impairment indicate a clinical disorder requiring active treatment. Option B represents poor practice - benzodiazepines like alprazolam can actually worsen PTSD outcomes by interfering with natural fear extinction and increasing dependency risk. Option C is premature and potentially harmful; graded exposure should only be conducted by trained professionals as part of structured therapy, not as self-directed treatment. For USMLE Step 3, remember that PTSD diagnosis requires symptoms lasting more than one month with functional impairment. Always choose evidence-based treatments: trauma-focused psychotherapy (like CPT or EMDR) is first-line, not medications or reassurance. Watch for questions that tempt you toward benzodiazepines for trauma - they're typically contraindicated.

Question 14

A 40-year-old man is evaluated in clinic 3 months after open reduction and internal fixation of a tibial plateau fracture. He complains of persistent, severe burning pain in his lower leg and foot that is disproportionate to the initial injury. He notes extreme sensitivity to light touch, such as bed sheets on his skin. On examination, the foot is swollen, slightly dusky, and cooler than the contralateral foot.

  1. A long-acting opioid, such as oxycodone ER.
  2. An oral corticosteroid taper over two weeks.
  3. A tricyclic antidepressant, such as amitriptyline. (correct answer)
  4. A muscle relaxant, such as cyclobenzaprine.
Explanation: This patient's constellation of symptoms—severe burning pain (hyperalgesia), pain from a non-painful stimulus (allodynia), and autonomic dysfunction (changes in skin color, temperature, swelling)—following trauma is classic for Complex Regional Pain Syndrome (CRPS). Management is multimodal, including physical therapy. First-line pharmacologic treatments are aimed at neuropathic pain and include tricyclic antidepressants (e.g., amitriptyline, nortriptyline), gabapentinoids (gabapentin, pregabalin), and topical agents. Opioids are not first-line and are generally avoided for chronic neuropathic pain.

Question 15

A 60-year-old woman who takes prednisone 15 mg daily for rheumatoid arthritis undergoes a laparoscopic cholecystectomy. On postoperative day 1, she develops hypotension to 80/50 mmHg that is refractory to a 2-liter intravenous fluid bolus. She is tachycardic to 125/min and has a low-grade fever. Her laboratory results show hyponatremia and hyperkalemia.

  1. Begin an infusion of norepinephrine.
  2. Administer intravenous hydrocortisone. (correct answer)
  3. Obtain an urgent abdominal CT to rule out a bile leak.
  4. Administer broad-spectrum antibiotics for sepsis.
Explanation: This patient's chronic use of high-dose corticosteroids has likely caused suppression of the hypothalamic-pituitary-adrenal (HPA) axis. The stress of surgery can precipitate an acute adrenal crisis in such patients if they do not receive perioperative stress-dose steroids. The presentation of refractory hypotension, fever, hyponatremia, and hyperkalemia is classic for adrenal crisis. The most critical and life-saving intervention is the immediate administration of intravenous hydrocortisone. While vasopressors and antibiotics may also be needed, treating the underlying adrenal insufficiency is paramount.

Question 16

A 62-year-old woman on postoperative day 7 from a total knee arthroplasty develops the acute onset of pleuritic chest pain and dyspnea. She has been receiving prophylactic enoxaparin. Her heart rate is 110/min, respiratory rate is 24/min, and oxygen saturation is 90% on room air. Her lungs are clear to auscultation. Her surgical incision is clean.

  1. Obtain a CT pulmonary angiography (CTPA). (correct answer)
  2. Obtain a ventilation-perfusion (V/Q) scan.
  3. Measure a serum D-dimer level.
  4. Perform a transthoracic echocardiogram.
Explanation: When you encounter a patient with acute onset pleuritic chest pain and dyspnea following major surgery, pulmonary embolism (PE) should be your primary concern. This 62-year-old woman has classic risk factors: recent orthopedic surgery, immobilization, and advanced age. Despite prophylactic anticoagulation, breakthrough PE can still occur, especially after high-risk procedures like knee arthroplasty. The correct answer is A because CT pulmonary angiography (CTPA) is the gold standard diagnostic test for PE in hemodynamically stable patients. It provides rapid, accurate visualization of pulmonary vessels and can detect emboli directly. Given her clear clinical presentation and intermediate-to-high pretest probability, immediate imaging is warranted. Option B, V/Q scanning, is primarily used when CTPA is contraindicated (renal insufficiency, contrast allergy) or unavailable. It's less specific and takes longer to complete. Option C, D-dimer measurement, would likely be elevated but lacks specificity in postoperative patients due to ongoing inflammation and healing processes. A negative D-dimer might be useful to rule out PE in low-risk patients, but this patient's high pretest probability makes it unhelpful. Option D, echocardiography, might show right heart strain in severe PE but cannot diagnose PE directly and wouldn't be the initial diagnostic test. Remember: In postoperative patients with suspected PE and intermediate-to-high pretest probability, proceed directly to CTPA rather than using screening tests like D-dimer. Time is critical, and definitive imaging provides both diagnosis and guides immediate treatment decisions.

Question 17

A 45-year-old man is in the ICU on postoperative day 3 following an emergency laparotomy for a perforated duodenal ulcer. He remains intubated and sedated. He has been NPO with maintenance IV fluids. His abdomen is distended with absent bowel sounds. His hemodynamic status is stable on low-dose vasopressors.

  1. Continue IV fluids alone until bowel sounds return.
  2. Initiate total parenteral nutrition (TPN) via his central line.
  3. Place a nasojejunal feeding tube and begin trophic enteral feeds. (correct answer)
  4. Initiate full-strength gastric feeds via his nasogastric tube.
Explanation: Early enteral nutrition (within 24-48 hours) is strongly recommended in critically ill patients to maintain gut mucosal integrity, reduce septic complications, and modulate the stress response. Waiting for bowel sounds to return is an outdated practice. TPN is associated with more complications (e.g., infection, cholestasis) and should be avoided if the gut is usable. Since the patient likely has a gastric ileus, post-pyloric feeding via a nasojejunal (or dobhoff) tube is the preferred method to deliver enteral nutrition. Starting with trophic ('trickle') feeds is a common strategy to assess tolerance.

Question 18

A 58-year-old man underwent a low anterior resection with a diverting loop ileostomy for rectal cancer. His postoperative course was complicated by a small, contained anastomotic leak diagnosed on POD 7, which was successfully managed non-operatively with bowel rest and IV antibiotics. He is now 4 weeks post-surgery, feeling well, and tolerating a diet. He is being seen to discuss the next steps in his care.

  1. He can be scheduled for ileostomy reversal in 2 to 4 weeks.
  2. He will require lifelong total parenteral nutrition.
  3. A contrast enema or flexible sigmoidoscopy should be performed prior to ileostomy reversal. (correct answer)
  4. The anastomosis should be resected and a permanent end colostomy created.
Explanation: Before reversing a diverting ileostomy, especially after an anastomotic leak, it is mandatory to confirm the integrity and healing of the downstream anastomosis. This is typically done with a contrast study (e.g., water-soluble contrast enema) or endoscopy to ensure there is no persistent leak, stricture, or other pathology. Proceeding with reversal without this confirmation would be unsafe. Scheduling reversal is premature. Lifelong TPN is not indicated. A permanent colostomy is not necessary if the leak has healed and the anastomosis is intact.

Question 19

An 82-year-old woman with dementia undergoes a hip hemiarthroplasty for a femoral neck fracture. On postoperative day 2, she becomes acutely agitated, disoriented to time and place, and is attempting to pull out her IV lines. Her vital signs are stable, oxygen saturation is 98% on room air, and a recent metabolic panel is unremarkable. Non-pharmacologic interventions like reorientation have failed.

  1. Administer a low dose of intravenous haloperidol. (correct answer)
  2. Apply soft wrist restraints to both arms.
  3. Administer a low dose of intravenous lorazepam.
  4. Request a neurology consultation for an emergent head CT.
Explanation: This patient is experiencing postoperative delirium, a common complication in elderly surgical patients. After ruling out and correcting underlying medical causes (hypoxia, electrolyte imbalance, infection, etc.), management focuses on non-pharmacologic strategies. When these fail and the patient's agitation poses a safety risk, a low-dose antipsychotic agent like haloperidol is the preferred pharmacologic treatment. Benzodiazepines (e.g., lorazepam) should be avoided as they can worsen delirium in the elderly (unless treating alcohol withdrawal). Restraints are a last resort and can exacerbate agitation.

Question 20

Two days after knee surgery, a 45-year-old woman on prophylactic LMWH develops sudden dyspnea and syncope; BP 82/50, HR 128; bedside echo shows RV dilation. Which intervention is most critical at this stage of care?​

  1. Administer systemic thrombolysis if no absolute contraindications are present (correct answer)
  2. Schedule outpatient V/Q scan because CT contrast may worsen kidney function
  3. Give nebulized bronchodilators for presumed postoperative bronchospasm
  4. Start oral anticoagulation only and avoid parenteral therapy initially
Explanation: This question tests USMLE Step 3 competencies in postoperative and post-trauma care, focusing on management strategies and complication prevention. Understanding the principles of postoperative care involves recognizing common complications and appropriate interventions based on clinical guidelines. In this scenario, the patient presents with sudden dyspnea, syncope, hypotension, tachycardia, and RV dilation on echo two days after knee surgery, necessitating consideration of massive pulmonary embolism management. Choice A is correct because it directly addresses the patient's current clinical needs, aligning with best practices for thrombolysis in hemodynamically unstable PE. Choice B is incorrect because it reflects a common misconception, such as delaying for outpatient imaging, leading to inadequate management and mortality risk. To enhance learning, students should focus on mastering complication recognition and prioritization of care, utilizing scenario-based practice to reinforce decision-making skills and prevent common clinical pitfalls.