All practice questions

A 68-year-old man is brought to the emergency department by his neighbor after collapsing in his driveway. The patient is awake but lethargic, complaining of agonizing, tearing pain in his left flank that radiates to his groin. His medical history includes hypertension, severe chronic obstructive pulmonary disease (COPD), and atrial fibrillation. He states he ran out of all his medications two weeks ago.

Vital signs are temperature 36.8°C (98.2°F), blood pressure 76/48 mmHg, heart rate 134/min and irregularly irregular, respiratory rate 28/min, and oxygen saturation 92% on room air.

Physical examination reveals a pale, diaphoretic patient who is oriented only to person. Pulmonary auscultation reveals diffuse expiratory wheezes. The abdomen is distended, firm, and diffusely tender with absent bowel sounds. Deep palpation reveals a prominent pulsatile mass in the periumbilical region. A bedside ultrasound demonstrates a 7.2-cm infrarenal aortic aneurysm with a surrounding hypoechoic collection in the retroperitoneum.

Which of the following is the most appropriate next step in management?

A surgical clerkship student is reviewing the classic presentations of cardiovascular and thoracic disorders. For each clinical scenario described below, select the most accurate diagnosis.

Match each patient's clinical presentation with the most appropriate next step in diagnosis or surgical management. Assume initial standard resuscitation (e.g., intravenous access, basic labs) has been initiated for all patients.

A $65$-year-old man presents to the clinic complaining of left-sided scrotal swelling and discomfort that he first noticed $1$ month ago. The patient describes a dull, heavy ache in the scrotum that worsens after standing for prolonged periods. Over the past $2$ weeks, he has also experienced intermittent left flank pain and noticed that his urine occasionally appears pink. His medical history is significant for hypertension and a $40$-pack-year smoking history. Vital signs are within normal limits. Physical examination in the standing position reveals a soft, irregular, cord-like mass superior to the left testicle. When the patient is placed in the supine position, the scrotal mass does not decrease in size. The testicles are bilaterally smooth, non-tender, and without discrete nodules. Which of the following is the most appropriate next step in the management of this patient?

A 28-year-old woman presents to the emergency department with a severe, diffuse headache, nausea, and three episodes of projectile vomiting that began 12 hours ago. She has a history of congenital hydrocephalus treated with a ventriculoperitoneal shunt placed during infancy; her last shunt revision was five years ago. Vitals show a blood pressure of 155/95 mmHg, heart rate of 52/min, respiratory rate of 12/min, and temperature of 37.0°C. Her Glasgow Coma Scale score is 14 (confused conversation). Neurologic examination reveals bilateral papilledema and impaired upward gaze, with no focal motor weakness in the extremities. Which of the following is the most appropriate next step in management?

A 68-year-old woman with a history of permanent atrial fibrillation and hypertension presents to the emergency department with a 3-hour history of sudden-onset, severe right leg pain. She admits to running out of her oral anticoagulant medication a week ago. On physical examination, the right foot and distal calf are pale and cool to the touch. Sensation to light touch is intact, and she can move all her toes without difficulty. Capillary refill is delayed. Palpation reveals a normal femoral pulse, but popliteal and pedal pulses are absent.

Arrange the following steps in the most appropriate sequential order for the evidence-based management of this patient's condition.

Match each clinical research scenario with its accurately calculated epidemiological measure.

A 72-year-old man is brought to the emergency department after experiencing a sudden onset of severe, tearing pain in his lower back and left flank. His wife states that he briefly lost consciousness at home. His medical history includes hypertension, hyperlipidemia, type 2 diabetes mellitus, and a 45-pack-year smoking history. He does not take any anticoagulant medications. On arrival, he is lethargic, pale, and diaphoretic. Vital signs are temperature 36.8°C (98.2°F), blood pressure 75/40 mmHg, heart rate 128/min, and respiratory rate 24/min. Physical examination reveals cold extremities with weak distal pulses. Abdominal examination demonstrates a tender, pulsatile mass in the periumbilical region. A bedside ultrasound confirms the presence of an infrarenal abdominal aortic dilation measuring 7.2 cm with an adjacent retroperitoneal hypoechoic fluid collection. Which of the following is the most appropriate next step in management?

A 64-year-old man is transported to the emergency department by ambulance following a sudden collapse at his residence. His spouse notes that prior to collapsing, he described an explosive pain in the back of his head, followed by severe vertigo, intractable emesis, and an inability to stand. His past medical history is significant for long-standing hypertension and medication nonadherence. On presentation, his blood pressure is 210/115 mm Hg, heart rate is 88/min, and respiratory rate is 16/min. He is immediately started on a continuous intravenous nicardipine infusion. Neurologic examination reveals a lethargic patient who arouses only to loud voice. He exhibits prominent left-sided finger-to-nose ataxia and horizontal nystagmus. A noncontrast CT scan of the head demonstrates a 4.2-cm hyperdense collection in the left cerebellar hemisphere with complete effacement of the fourth ventricle and marked enlargement of the lateral and third ventricles. Which of the following is the most appropriate definitive management for this patient?

A 45-year-old man is brought to the emergency department after a heavy concrete pipe rolled over his lower torso at a construction site. On arrival, his airway is patent, and breath sounds are equal bilaterally. His blood pressure is 78/45 mmHg and his pulse is 132/min. There is no visible external hemorrhage. Physical examination reveals ecchymosis over the perineum and severe instability of the pelvic ring upon gentle lateral compression. A focused assessment with sonography for trauma (FAST) examination reveals no intraperitoneal free fluid. Which of the following is the most appropriate next step in management?

To evaluate the efficacy of a novel sodium-glucose cotransporter-2 (SGLT2) inhibitor in preventing cardiovascular mortality, a multicenter, double-blind trial enrolls patients with chronic heart failure. Participants are randomly assigned to receive either the SGLT2 inhibitor or a placebo. After a median follow-up of three years, the data are analyzed. Among the $2,000$ patients in the intervention group, $240$ experienced a cardiovascular mortality event. In the control group, which also consisted of $2,000$ patients, $320$ experienced a cardiovascular mortality event. Based on these findings, what is the number needed to treat to prevent one cardiovascular mortality event over the study period?

Match each epidemiological research scenario with the specific type of bias or confounding it best represents.

Match each epidemiological scenario or study result with the specific research concept (bias or confounding) it best illustrates.

A research group conducts a randomized, double-blind, placebo-controlled trial to evaluate the efficacy of a novel biologic agent for patients with severe, treatment-resistant rheumatoid arthritis. The study's primary endpoint is the proportion of patients achieving clinical remission at $6$ months. During the trial design phase, the researchers determine that $500$ patients are required to achieve $80\%$ power to detect a $10\%$ absolute difference in remission rates, with an $\alpha$ level of $0.05$. The trial ultimately enrolls $500$ patients; however, due to unforeseen logistical challenges during the study period, $35\%$ of the enrolled participants are lost to follow-up and excluded from the final primary analysis. The final results show a $9\%$ absolute higher remission rate in the treatment group compared to the placebo group, with a $p$-value of $0.07$ and a $95\%$ confidence interval for the difference ranging from $-1\%$ to $+19\%$. Which of the following best explains why the trial failed to demonstrate a statistically significant benefit for the novel biologic agent?

Match each infectious disease presentation to the most appropriate mandatory public health action or infection control protocol.

A 65-year-old man is evaluated on postoperative day 4 following a robotic-assisted laparoscopic radical prostatectomy for localized prostate adenocarcinoma. A urethral catheter was left in place at the end of the procedure. On postoperative day 2, he developed a fever of 38.8°C (101.8°F), chills, and suprapubic discomfort. Blood and urine cultures were obtained, and empiric intravenous piperacillin-tazobactam was initiated. Today, the patient is afebrile, and his vital signs are within normal limits. He reports complete resolution of his chills and suprapubic pain. The abdomen is soft and non-tender, and the urethral catheter is draining clear yellow urine. The blood cultures show no growth. The urine culture from postoperative day 2 returns with the following results:

Which of the following is the most appropriate next step in management?

Public health officials review data from a large population registry to investigate the relationship between residential proximity to major highways and the development of childhood asthma. An initial unadjusted analysis reveals a relative risk of 2.1 (95% CI: 1.6-2.8) for asthma in children living within 100 meters of a highway compared to those living farther away. The researchers subsequently conduct a stratified analysis based on household income levels. The relative risk for asthma among children in low-income households is 1.1 (95% CI: 0.8-1.4), and the relative risk among children in high-income households is 1.2 (95% CI: 0.9-1.5). Which of the following epidemiologic phenomena best explains the discrepancy between the initial and stratified findings?

Match each clinical research scenario with the most appropriate epidemiologic study design.

A randomized, double-blind, placebo-controlled trial evaluates a new calcitonin gene-related peptide (CGRP) antagonist for the prevention of chronic migraines. A total of 1,000 adult patients with a history of chronic migraines are enrolled and randomized in a 1:1 ratio to receive either the CGRP antagonist or a matched placebo. The primary study endpoint is the proportion of patients achieving at least a 50% reduction in monthly migraine days over a 12-week period.

At the conclusion of the 12-week study, the following results are reported:
- Placebo group: 150 out of 500 patients met the primary endpoint.
- Treatment group (CGRP antagonist): 275 out of 500 patients met the primary endpoint.

The findings are determined to be statistically significant ($p < 0.01$). Based on these trial results, what is the number needed to treat (NNT) to achieve the primary endpoint in one additional patient? (Provide the exact whole number).

Match each brain herniation syndrome with its most characteristic clinical presentation or pathophysiologic consequence as seen in acute neurotrauma or expanding intracranial mass lesions.