Internal Medicine

Match each primary acid-base disorder to its corresponding expected physiological compensatory response.

A 75-year-old man presents to the emergency department with acute-onset, severe dyspnea that woke him from sleep. He has a history of a myocardial infarction 5 years ago and a 45-pack-year smoking history. His blood pressure is 165/95 mmHg, heart rate is 112/min, and respiratory rate is 28/min. Pulse oximetry is 88% on room air. He is visibly distressed, sitting on the edge of the stretcher, and coughing up pink, frothy sputum. Pulmonary auscultation reveals diffuse bilateral wheezes and scattered crackles. Which of the following physical examination findings would most strongly support a primary cardiac etiology for this patient's acute respiratory distress over a primary pulmonary exacerbation?

Paramedics bring a 72-year-old man to the emergency department due to a 1-day history of severe dyspnea and increasing somnolence. His medical history includes severe chronic obstructive pulmonary disease (COPD) requiring continuous home oxygen, heart failure with a left ventricular ejection fraction of $35\%$, and essential hypertension. Upon arrival, his temperature is $37.1^\circ$ C ($98.8^\circ$ F), blood pressure is $165/95$ mm Hg, heart rate is $118$/min, and respiratory rate is $28$/min. Oxygen saturation is $84\%$ on his baseline $2$ L/min via nasal cannula. He is lethargic but arouses to loud verbal stimuli. Physical examination reveals an elevated jugular venous pressure of $13$ cm $H_2O$. Lung auscultation demonstrates diffuse, bilateral expiratory wheezing and prominent bibasilar fine crackles. Cardiac auscultation reveals a regular tachycardia with a distinct third heart sound ($S_3$). There is $2+$ bilateral pitting edema of the lower extremities. Laboratory studies show a leukocyte count of $8,500/mm^3$. An arterial blood gas analysis obtained on $2$ L/min of oxygen reveals:

$pH$: $7.22$
$PaCO_2$: $72$ mm Hg
$PaO_2$: $52$ mm Hg
$HCO_3^-$: $30$ mEq/L

A trial of noninvasive positive pressure ventilation (NIPPV) is immediately initiated. Which of the following is the most appropriate additional next step in the management of this patient?

Match each patient's clinical presentation with the most appropriate antimicrobial stewardship-guided management step.

A 55-year-old man is brought to the emergency department by his wife due to progressively worsening shortness of breath and lethargy over the past week. His wife reports he recently had a mild viral upper respiratory tract infection and has been falling asleep mid-conversation for the past two days. His medical history is significant for morbid obesity, hypertension, and type 2 diabetes mellitus. He has a 5-pack-year smoking history but quit 15 years ago.

Vital signs are:
Temperature: $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$)
Pulse: $98\text{/min}$
Blood pressure: $145/90\text{ mmHg}$
Respiratory rate: $22\text{/min}$
$SpO_2$: $84\%$ on room air
BMI: $46\text{ kg/m}^2$

Physical examination shows a somnolent but easily arousable obese man. Jugular venous pulsation is visible $9\text{ cm}$ above the sternal angle. Chest auscultation reveals shallow, distant breath sounds bilaterally with no crackles or wheezes. Cardiac examination shows a regular rhythm with a prominently split second heart sound and a loud pulmonic component ($P_2$). The abdomen is protuberant. There is 3+ pitting edema of the bilateral lower extremities extending to the knees.

Laboratory results reveal a leukocyte count of $8,500/\mu\text{L}$ and a B-type natriuretic peptide (BNP) level of $110\text{ pg/mL}$ (normal: $<100\text{ pg/mL}$). Chest radiography shows an enlarged main pulmonary artery but clear lung fields without infiltrates, effusions, or cardiomegaly.

Arterial blood gas analysis on room air reveals:
pH: $7.31$
$PaCO_2$: $62\text{ mmHg}$
$PaO_2$: $55\text{ mmHg}$
$HCO_3^-$: $31\text{ mEq/L}$

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

A 45-year-old woman is being evaluated for progressive weight gain, proximal muscle weakness, and easy bruising. Physical examination reveals central adiposity, wide purple abdominal striae, facial plethora, and a blood pressure of 160/100 mmHg. The physician suspects Cushing syndrome. Assuming each step dictates the need for the subsequent one to identify an occult etiology, arrange the following diagnostic procedures in the correct sequential order, from initial confirmation to final localization.

Match each esophageal motility disorder with its most characteristic finding on high-resolution esophageal manometry.

A 32-year-old woman is evaluated in the urgent care clinic due to severe nausea, diffuse abdominal discomfort, and a persistent "ringing" sensation in her ears for the past day. She reports a history of chronic lower back pain and admits to taking a large handful of over-the-counter analgesic tablets recently to manage a severe flare-up.

Vital signs show a temperature of 38.1°C (100.6°F), blood pressure of 114/72 mm Hg, pulse of 116/min, and respiratory rate of 28/min. She appears flushed and diaphoretic. Lungs are clear to auscultation.

Laboratory results are as follows:

Which of the following best characterizes this patient's current acid-base disturbance?

A $64$-year-old man with a history of alcohol-related cirrhosis and major depressive disorder is hospitalized for worsening abdominal distension and fever. His home medications include spironolactone, furosemide, lactulose, and citalopram. On admission, his temperature is $38.1$°C ($100.6$°F) and blood pressure is $105/65$ mmHg. Physical examination reveals shifting dullness and trace bilateral pedal edema.

Diagnostic paracentesis yields ascitic fluid with a leukocyte count of $1,100$/mm³ ($85\%$ neutrophils). Arterial blood gas analysis on room air reveals:
pH: $7.29$
pCO $_2$: $29$ mmHg
HCO $_3^-$: $14$ mEq/L

The patient is empirically started on intravenous piperacillin-tazobactam and vancomycin, and he receives intravenous albumin on hospital day 1. On hospital day 3, his temperature has decreased to $37.1$°C ($98.8$°F) and his abdominal pain has resolved. The ascitic fluid culture from admission grows *Escherichia coli* that is resistant to ampicillin but susceptible to ceftriaxone, cefepime, piperacillin-tazobactam, and ciprofloxacin. Blood cultures show no growth.

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

A 34-year-old man with a history of intravenous drug use presents to the emergency department with a 4-day history of high fever, chills, and profound fatigue. His temperature is 39.2°C (102.6°F), blood pressure is 110/65 mm Hg, and heart rate is 112/min. Physical examination reveals a new holosystolic murmur at the left lower sternal border that increases in intensity with inspiration, as well as painless, erythematous macules on his palms.

Arrange the following diagnostic and therapeutic management steps in the most appropriate chronological sequence for this patient.

Match each patient's clinical presentation and laboratory evaluation to the most likely underlying diagnosis or pathophysiologic mechanism.

While rounding in the surgical intensive care unit, a physician is called to the bedside of a $72$-year-old male who has developed abrupt respiratory distress and confusion. The patient underwent an open right hemicolectomy for colon adenocarcinoma three days prior. Until this morning, his recovery was unremarkable. Current vital signs include a temperature of $38.1^\circ\text{C}$ ($100.6^\circ\text{F}$), heart rate of 134/min, respiratory rate of 28/min, and blood pressure of 82/48 mmHg. Pulse oximetry reveals an oxygen saturation of 85% on room air.

Physical examination shows profound diaphoresis and jugular venous distention visible up to the angle of the mandible while sitting at a 45-degree angle. The surgical incision appears clean and intact with no surrounding erythema. Pulmonary ausculation yields clear breath sounds bilaterally without wheezes or crackles. Cardiac auscultation reveals a loud pulmonic component of the second heart sound (P2) and an S3 gallop best heard at the lower left sternal border.

A 12-lead electrocardiogram displays sinus tachycardia with new T-wave inversions in leads V1 through V4 and a rightward shift of the QRS axis. Which of the following is the most appropriate next step in the management of this patient?

A 73-year-old woman is brought to the emergency department at 2:00 AM by ambulance due to severe, worsening shortness of breath. She reports waking up abruptly gasping for air and feeling a tight sensation in her chest. Her medical history includes type 2 diabetes mellitus, hypertension, hyperlipidemia, and a 45-pack-year smoking history. She currently smokes half a pack of cigarettes daily. Temperature is 36.8°C (98.2°F), blood pressure is 178/102 mm Hg, pulse is 114/min, and respirations are 28/min. Pulse oximetry is 85% on room air. The patient is sitting upright on the edge of the stretcher, diaphoretic, and using accessory muscles of respiration. Physical examination reveals a jugular venous pressure estimated at 11 cm $H_2O$. Lung auscultation demonstrates diffuse expiratory wheezes and crackles halfway up both posterior lung fields. Cardiac auscultation reveals a regular tachycardia and a prominent third heart sound ($S_3$). The bilateral lower extremities exhibit 2+ pitting edema extending to the shins. Electrocardiogram shows sinus tachycardia and left ventricular hypertrophy. Which of the following is the most appropriate initial pharmacological management for this patient?

Match each of the following clinical and laboratory profiles with the most likely pathophysiologic diagnosis.

Match each patient's preoperative medication profile with the most appropriate perioperative management strategy for that specific medication.

A 54-year-old man presents to the clinic reporting a 4-month history of persistent fatigue, sluggishness, and increased sensitivity to cold. He also mentions a recent decline in his sexual drive and difficulty maintaining an erection. He has no past medical history and takes no medications. His temperature is $36.2^{\circ}\text{C}$ ($97.2^{\circ}\text{F}$), blood pressure is $108/68\text{ mm Hg}$, and pulse is $55\text{/min}$. Physical examination demonstrates pale, dry skin and a noticeable delay in the relaxation phase of the patellar reflexes. Confrontational visual field testing detects a deficit in the temporal fields bilaterally.

Laboratory results are as follows:
Thyroid-stimulating hormone (TSH): $1.8\text{ }\mu\text{IU/mL}$ (normal: $0.4-4.0\text{ }\mu\text{IU/mL}$)
Free thyroxine (T4): $0.5\text{ ng/dL}$ (normal: $0.9-1.7\text{ ng/dL}$)
Total testosterone: $140\text{ ng/dL}$ (normal: $300-1,000\text{ ng/dL}$)

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

A 72-year-old man is brought to the emergency department from a long-term care facility due to a 4-day history of profuse, watery diarrhea and progressive lethargy. His medical history includes hypertension, benign prostatic hyperplasia, and moderate chronic obstructive pulmonary disease. His medications include amlodipine, tamsulosin, and an albuterol inhaler as needed. Temperature is $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), blood pressure is 98/62 mm Hg, pulse is 114/min, and respirations are 24/min. Physical examination shows dry mucous membranes, delayed capillary refill, and decreased skin turgor. Lungs are clear to auscultation bilaterally.

Which of the following best describes this patient's acid-base status?

Emergency medical services bring a 67-year-old man to the hospital due to profound lethargy and reduced urine output over the last 24 hours. His medical history includes severe chronic obstructive pulmonary disease (COPD) and ischemic cardiomyopathy. A legally binding advance directive in his electronic medical record designates his wife as his healthcare proxy; she has previously consented to all life-saving interventions. Currently, his son is at the bedside and explicitly demands that no breathing tubes be placed. Vital signs reveal a temperature of 38.9°C (102.0°F), blood pressure of 82/45 mm Hg, pulse of 126/min, and respirations of 32/min. Physical examination shows a somnolent patient who only localizes to painful stimuli. Jugular venous pressure is 5 cm H₂O. Lung auscultation demonstrates diminished breath sounds bilaterally with shallow inspiratory efforts. The patient receives 3 liters of intravenous crystalloids, broad-spectrum antibiotics, and a norepinephrine infusion. A brief accidental disconnection of his oxygen tubing by a staff member is noted and immediately corrected. Arterial blood gas analysis on room air shows:

pH: $7.23$
PaCO₂: $35 \text{ mm Hg}$
PaO₂: $72 \text{ mm Hg}$
HCO₃⁻: $14 \text{ mEq/L}$

Based on these findings, which of the following is the most appropriate next step in management?

A 65-year-old man is brought to the emergency department by his family due to a 2-day history of worsening shortness of breath and an increase in the volume and purulence of his sputum. His medical history includes chronic obstructive pulmonary disease and mild heart failure with preserved ejection fraction. Vital signs show a temperature of 37.4°C (99.3°F), blood pressure of 138/86 mm Hg, heart rate of 108/min, respiratory rate of 24/min, and oxygen saturation of 89% on room air. Physical examination reveals a prolonged expiratory phase with diffuse expiratory wheezing bilaterally. There is no jugular venous distention, and no lower extremity edema is appreciated. A chest radiograph demonstrates hyperinflated lung fields and flattened diaphragms without focal consolidations or pleural effusions. An arterial blood gas analysis on room air shows a pH of 7.32, PaCO2 of 54 mm Hg, and PaO2 of 58 mm Hg. Which of the following are appropriate initial management steps for this patient? (Select all that apply)

A 65-year-old woman is evaluated in the emergency department due to a two-day history of progressively worsening shortness of breath, a cough productive of yellow sputum, and a sensation of a racing heartbeat. Her medical history includes chronic obstructive pulmonary disease (COPD) and essential hypertension. Her daily home medications include an inhaled long-acting muscarinic antagonist and a low-dose thiazide diuretic. Vital signs show a temperature of 37.5°C (99.5°F), blood pressure of 132/84 mmHg, pulse of 128/min, and respiratory rate of 24/min. Pulse oximetry on room air is 88%. Physical examination reveals a prolonged expiratory phase with diffuse bilateral expiratory wheezing, but no inspiratory crackles. The jugular venous pressure is 8 cm H2O. Cardiac auscultation reveals an irregularly irregular rhythm with a loud P2, but no S3 gallop or murmurs are appreciated. Trace bilateral lower extremity edema is present. An electrocardiogram demonstrates a narrow QRS complex tachycardia with an irregular R-R interval, varying PR intervals, and three distinct P-wave morphologies in lead II. Which of the following is the most appropriate initial management for this patient's condition?