All practice questions

A $62$-year-old man presents to the emergency department with a $4$-hour history of severe, unrelenting abdominal pain and nonbilious vomiting. He has a history of an open cholecystectomy $12$ years ago. His temperature is $37.3^\circ\text{C}$ ($99.1^\circ\text{F}$), blood pressure is $135/85\text{ mmHg}$, pulse is $88/\text{min}$, and respirations are $16/\text{min}$. Physical examination reveals a moderately distended abdomen. There is diffuse tenderness to deep palpation, but no involuntary guarding, rigidity, or rebound tenderness is present. Laboratory studies show a leukocyte count of $9,800/\text{mm}^3$ and a serum lactate level of $1.1\text{ mmol/L}$. Computed tomography of the abdomen and pelvis with intravenous contrast reveals a high-grade mechanical small bowel obstruction. A transition point is identified in the mid-ileum, accompanied by a cluster of dilated, fluid-filled bowel loops arranged in a U-shaped configuration. The mesenteric vessels supplying this segment demonstrate a "whirl" pattern. The bowel wall shows normal contrast enhancement, and there is no pneumatosis intestinalis or free intraperitoneal air.

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

A pharmaceutical company conducts a randomized, double-blind non-inferiority trial comparing a novel once-daily oral antibiotic to the standard thrice-daily intravenous therapy for the treatment of uncomplicated pyelonephritis. The primary endpoint is the clinical cure rate at $14$ days. The investigators establish a predefined non-inferiority margin ($\Delta$) of $-6.0\%$, meaning the new oral antibiotic will be deemed non-inferior if its cure rate is no more than $6.0$ absolute percentage points lower than the standard therapy.

Upon study completion, the absolute difference in clinical cure rates (novel antibiotic minus standard therapy) is calculated to be $-3.0\%$. The $95\%$ confidence interval (CI) for this difference is $[-5.2\%, -0.8\%]$, with a one-sided $p$-value of $0.01$ for non-inferiority.

Based on the information above, which of the following is the most accurate statistical interpretation of these trial results?

A 33-year-old gravid 3, para 2 woman at 38 weeks of gestation is evaluated in the labor unit. She was admitted in active labor 2 hours ago. Her past medical history is notable for a laparoscopic myomectomy three years ago that required extensive entry into the uterine cavity. She has been comfortable on continuous epidural analgesia until 10 minutes ago, when she reports the sudden onset of severe, tearing lower abdominal pain that radiates to her left shoulder. Her blood pressure is $82/48$ mm Hg, and her pulse is $132$/min. The tocodynamometer reveals a sudden cessation of previously regular uterine contractions. Fetal heart rate monitoring demonstrates an abrupt deceleration to $80$/min that has persisted for 4 minutes without recovery. On sterile vaginal examination, the fetal presenting part has receded from $0$ station to $-3$ station. Which of the following is the most appropriate next step in management?

A $29$-year-old woman is brought to the emergency department by her husband due to severe dizziness, lethargy, and confusion that has worsened over the past $48$ hours. She gave birth to a healthy infant $5$ months ago; the delivery was complicated by uterine atony and severe postpartum hemorrhage requiring emergent transfusion of $4$ units of packed red blood cells. Since the delivery, she has been unable to breastfeed and has not resumed menstruation. Her pulse is $115$/min, and blood pressure is $82/50$ mm Hg. Physical examination reveals delayed capillary refill, dry mucous membranes, and loss of axillary and pubic hair. Laboratory studies show:

Serum sodium: $131$ mEq/L
Serum potassium: $4.1$ mEq/L
Serum glucose: $58$ mg/dL
Thyroid-stimulating hormone (TSH): $0.3$ mU/L (Normal: $0.5$ - $5.0$)
Free thyroxine (T4): $0.5$ ng/dL (Normal: $0.9$ - $1.7$)

Which of the following is the most appropriate initial step in the management of this patient?

Match each patient's clinical presentation with the most likely corresponding finding on a peripheral blood smear.

A 52-year-old man is brought to the emergency department by his wife due to worsening confusion, unsteadiness, and a prominent tremor over the past three days. He has a history of bipolar I disorder that has been well controlled on lithium carbonate for the past five years. Two weeks ago, he was diagnosed with essential hypertension, and a new daily medication was added to his regimen. His temperature is 37.1 C (98.8 F), blood pressure is 135/85 mm Hg, and pulse is 88/min. On examination, the patient is lethargic but arousable. Neurological examination reveals dysarthria, an unsteady, broad-based gait, and a coarse resting tremor in both hands. Laboratory studies show a serum creatinine of 1.2 mg/dL (baseline 0.9 mg/dL) and a serum lithium level of 2.1 mEq/L (therapeutic range: 0.6-1.2 mEq/L). Which of the following best describes the mechanism by which the new antihypertensive medication precipitated this patient's condition?

A 28-year-old woman comes to the office with her partner for evaluation of an inability to conceive for the past 14 months. She has a history of irregular menstrual cycles occurring every 35 to 90 days. Her last menstrual period was 10 weeks ago. Recently, she has felt unusually fatigued and has experienced mild nausea upon awakening. She takes a daily prenatal vitamin. Blood pressure is $112/70 \text{ mm Hg}$, and pulse is $88/\text{min}$. BMI is $27 \text{ kg/m}^2$. Physical examination shows mild facial acne. Pelvic examination reveals a soft, slightly enlarged globular uterus and a bluish discoloration of the cervix. Laboratory studies obtained at a health fair last week show:

Thyroid-stimulating hormone (TSH): $0.1 \text{ mU/L}$ (N: $0.4-4.0 \text{ mU/L}$)
Total thyroxine (T4): $13.5 \text{ \mu g/dL}$ (N: $5.0-12.0 \text{ \mu g/dL}$)
Prolactin: $35 \text{ ng/mL}$ (N: $< 20 \text{ ng/mL}$)

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

A $24$-year-old woman is brought to the emergency department due to progressive confusion, nausea, vomiting, and severe abdominal pain over the past $24$ hours. She has a history of type 1 diabetes mellitus but reports running out of her medications three days ago. Her temperature is $37.2^\circ\text{C}$ ($99.0^\circ\text{F}$), blood pressure is $90/60\text{ mmHg}$, pulse is $128\text{/min}$, and respirations are $26\text{/min}$ and deep. Mucous membranes are dry. Laboratory studies show:

Blood glucose: $650\text{ mg/dL}$
Serum sodium: $132\text{ mEq/L}$
Serum potassium: $3.1\text{ mEq/L}$
Serum chloride: $98\text{ mEq/L}$
Serum bicarbonate: $11\text{ mEq/L}$
Arterial pH: $7.15$
Serum ketones: Positive

Arrange the following therapeutic interventions in the correct chronological order for the evidence-based management of this patient's condition.

A 74-year-old man requires evaluation in the orthopedic ward four days after undergoing a right hip hemiarthroplasty for a femoral neck fracture. Over the last 12 hours, he has experienced progressively worsening shortness of breath, chest tightness, and a new-onset cough producing small amounts of clear sputum. His past medical history is significant for hypertension and moderate chronic obstructive pulmonary disease. His home medications, which include a daily fluticasone-salmeterol inhaler, were inadvertently not restarted after the procedure. His temperature is 38.1°C (100.6°F), blood pressure is 138/86 mmHg, pulse is 108/min, and respiratory rate is 22/min. Pulse oximetry shows 91% on room air. Physical examination reveals a prolonged expiratory phase and diffuse expiratory wheezing over all lung fields. There is no jugular venous distention, and heart sounds are normal without gallops or murmurs. The surgical incision is clean, dry, and intact with no surrounding erythema. There is no unilateral lower extremity edema. A chest radiograph demonstrates hyperinflated lung fields and flattened hemidiaphragms, without focal consolidation, pleural effusion, or pulmonary vascular congestion. An electrocardiogram shows sinus tachycardia without right heart strain. Which of the following is the most appropriate next step in the management of this patient?

A 54-year-old man is brought to the emergency department by paramedics after being found stuporous in a local park. Beside him, paramedics found several empty bottles of antifreeze. His temperature is $36.5^\circ\text{C}$ ($97.7^\circ\text{F}$), blood pressure is $105/65\text{ mmHg}$, pulse is $98/\text{min}$, and respirations are $14/\text{min}$. Physical examination reveals a lethargic patient who arouses to painful stimuli but is unable to answer questions. Cardiopulmonary examination is unremarkable.

The following laboratory results are obtained:

Arterial blood gas analysis on room air reveals:

Which of the following best describes this patient's primary acid-base disturbance(s)?

A $62$-year-old woman presents to the emergency department with a sudden onset of right-sided chest pain that worsens with deep inspiration, accompanied by severe shortness of breath. Her symptoms started $2$ hours ago. She recently returned from a $12$-hour international flight. Her medical history includes hypertension and osteoarthritis. She takes amlodipine and acetaminophen.

Upon evaluation, her temperature is $37.2^\circ\text{C}$ ($99.0^\circ\text{F}$), blood pressure is $118/76\text{ mmHg}$, pulse is $118/\text{min}$, and respiratory rate is $26/\text{min}$. Oxygen saturation is $89\%$ on room air. Physical examination reveals clear lung fields bilaterally with no wheezing or crackles. Cardiac examination shows a regular, rapid rhythm with no murmurs, rubs, or gallops. The right calf is mildly swollen and tender to palpation compared to the left.

An arterial blood gas analysis on room air reveals:
pH: $7.52$
$\text{PaCO}_2$: $26\text{ mmHg}$
$\text{PaO}_2$: $60\text{ mmHg}$
$\text{HCO}_3^-$: $21\text{ mEq/L}$

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

A 38-year-old man presents to the clinic with a 3-month history of episodic, severe headaches accompanied by profuse sweating and a racing heartbeat. His blood pressure in the clinic is 178/104 mmHg, and his heart rate is 108/min. He has no other significant past medical history and takes no medications. Physical examination is unremarkable. Suspecting a specific catecholamine-secreting neuroendocrine tumor, the physician plans to evaluate and treat the patient. Arrange the following steps in the correct chronological order for the appropriate evidence-based diagnosis and management of this patient's condition.

A 71-year-old woman is brought to the emergency department from a skilled nursing facility due to progressively worsening altered mental status over the past 24 hours. Her medical history includes chronic obstructive pulmonary disease, type 2 diabetes mellitus, and hypertension. Vital signs are temperature $38.9^\circ\text{C}$ ($102.0^\circ\text{F}$), blood pressure 82/50 mmHg, pulse 118/min, and respirations 26/min. Oxygen saturation is 94% on room air. Physical examination reveals dry mucous membranes and suprapubic tenderness. The lungs are clear to auscultation bilaterally. Cardiac examination shows tachycardia with a regular rhythm and no murmurs.

Laboratory and diagnostic results are as follows:

Urinalysis shows 3+ leukocyte esterase, positive nitrites, and >50 leukocytes/hpf. A central venous catheter is placed, and aggressive intravenous fluid resuscitation is initiated. Blood and urine cultures are pending.

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

A 32-year-old G1P0 woman at 30 weeks gestation comes to the emergency department due to progressively worsening shortness of breath and orthopnea over the past two weeks. She says she has to prop herself up on three pillows at night to breathe comfortably. Medical history is significant for Hodgkin lymphoma diagnosed 5 years ago, which was successfully treated with six cycles of a chemotherapy regimen containing doxorubicin. She also has a history of mild asthma for which she uses an albuterol inhaler as needed. Her temperature is 37.0°C (98.6°F), blood pressure is 112/70 mm Hg, pulse is 108/min, and respirations are 24/min. Pulse oximetry is 94% on room air. Physical examination shows prominent jugular venous distention. Cardiac auscultation reveals a regular rate and rhythm with an apical S3 gallop. Lung auscultation reveals fine bibasilar crackles without wheezing. There is 2+ bilateral pitting edema in the lower extremities. Laboratory studies show:

Which of the following is the most likely underlying mechanism for this patient's current presentation?

A 68-year-old man comes to the clinic accompanied by his daughter to discuss the results of a recent excisional biopsy of an enlarged cervical lymph node. The pathology report confirms a diagnosis of diffuse large B-cell lymphoma. While the patient is in the restroom, the daughter approaches the physician in the hallway. She tearfully requests that her father not be told if the diagnosis is cancer. She explains, "He has a history of severe major depressive disorder. When my mother passed away five years ago, he attempted suicide and required a lengthy admission to a psychiatric facility. I am absolutely certain that if you tell him he has cancer, he will lose all hope and try to kill himself again." The patient is currently alert, cooperative, and has been actively participating in his medical workup. When the patient returns to the examination room, he sits down and says, "Alright doctor, I know we are here for the biopsy results. Please give it to me straight. Do I have cancer?" Which of the following is the most appropriate next step in management?

A primary care clinic evaluates several patients with varying medical histories. Based on current Centers for Disease Control and Prevention (CDC) guidelines, match each patient's clinical profile with the most appropriate vaccine recommendation or contraindication.

A public health task force is reviewing the performance characteristics of various screening and diagnostic tests. Match each of the following changes in test application or interpretation with its direct mathematical consequence on the test's performance parameters.

A 74-year-old retired teacher is evaluated in the emergency department for sudden, excruciating pain in his right lower extremity that began 3 hours ago. He reports that his foot feels cold and he cannot move his toes. His past medical history includes hypertension, osteoarthritis, and paroxysmal atrial fibrillation. He is not currently taking anticoagulation due to a history of peptic ulcer disease. His pulse is 112/min and irregularly irregular, and his blood pressure is 152/88 mm Hg. Physical examination reveals a pale, cold right leg from the mid-calf distally. The right femoral pulse is palpable, but the popliteal and pedal pulses are absent. There is profound sensory loss over the dorsum of the foot, and the patient is unable to actively dorsiflex his ankle. Continuous-wave Doppler ultrasound detects venous signals but no arterial signals over the dorsalis pedis artery. Which of the following is the most appropriate next step in management?

A public health task force is redesigning the diagnostic pathways for an emerging infectious disease. Match each proposed strategic or epidemiological adjustment on the left with its precise mathematical effect on diagnostic and screening test performance metrics on the right.

A $68$-year-old woman comes to the emergency department reporting severe difficulty breathing and wheezing for the past two days. She has a history of type 2 diabetes, hypertension, and severe chronic obstructive pulmonary disease (COPD). She reports a recent upper respiratory tract infection. Her home medications include metformin, lisinopril, and a tiotropium inhaler. She has been using her rescue albuterol inhaler multiple times today with minimal relief.

She reports an increase in breathlessness, but states her sputum remains clear and sparse. She denies chest pain, orthopnea, paroxysmal nocturnal dyspnea, or swelling in her legs. Temperature is $37.2^\circ\text{C}$ ($99.0^\circ\text{F}$), pulse is $118\text{/min}$, blood pressure is $138/86\text{ mmHg}$, and respiratory rate is $28\text{/min}$. Pulse oximetry shows $88\%$ on room air.

Physical examination reveals an anxious woman using accessory muscles of respiration. Lung auscultation demonstrates diffuse, bilateral expiratory wheezing with a prolonged expiratory phase. Jugular venous pressure is estimated at $6\text{ cm H}_2\text{O}$. Trace bilateral pedal edema is noted, which the patient states is chronic.

A rapid multiplex respiratory polymerase chain reaction (PCR) panel is positive for rhinovirus. Chest radiograph shows lung hyperinflation with flattened hemidiaphragms. There is no focal consolidation, pleural effusion, or cardiomegaly.

Which of the following interventions are indicated for the initial management of this patient? (Select 2)