Pulmonary and Critical Care

A 54-year-old man is evaluated in the intensive care unit on hospital day 3. He was initially admitted for community-acquired pneumonia and septic shock, requiring endotracheal intubation, mechanical ventilation, and vasopressor support. His empiric antibiotic regimen was de-escalated to intravenous ceftriaxone and oral azithromycin two days ago based on sputum cultures confirming *Streptococcus pneumoniae*.

Today, his blood pressure has improved to $115/75\text{ mm Hg}$ on a minimal weaning dose of norepinephrine, and his temperature is $37.4^\circ\text{C}$ ($99.3^\circ\text{F}$). He remains deeply sedated and is not initiating spontaneous breaths.

Current ventilator settings (Volume Assist-Control):
Tidal Volume: $450\text{ mL}$
Respiratory Rate: $12/\text{min}$
$\text{FiO}_2$: $0.35$
PEEP: $5\text{ cm H}_2\text{O}$

Which of the following are appropriate management steps for this patient? (Select all that apply)

A 52-year-old man presents to the clinic reporting progressively worsening swelling in his lower extremities and profound daytime fatigue over the past four months. His wife, who accompanies him, notes that he frequently falls asleep during conversations and snores loudly at night. His medical history includes obesity, essential hypertension, and diet-controlled type 2 diabetes mellitus. He has no history of tobacco use.

Vital signs show a temperature of $36.8^\circ\text{C}$ ($98.2^\circ\text{F}$), heart rate of $88/\text{min}$, blood pressure of $135/85\text{ mmHg}$, respiratory rate of $14/\text{min}$, and oxygen saturation of $89\%$ on room air. BMI is $42\text{ kg/m}^2$.

Physical examination reveals prominent jugular venous distention with noticeable *a* waves. Cardiac auscultation demonstrates a right ventricular heave, a loud pulmonic component of the second heart sound ($P_2$), and a holosystolic murmur at the left lower sternal border that increases in intensity with inspiration. The lungs are clear to auscultation bilaterally. Bilateral $3+$ pitting edema is present up to the knees.

Laboratory studies show:
Hemoglobin: $16.8\text{ g/dL}$
Thyroid-stimulating hormone (TSH): $2.5\text{ \mu U/mL}$ (Normal: $0.4-4.0\text{ \mu U/mL}$)
Free T4: $1.2\text{ ng/dL}$ (Normal: $0.9-1.7\text{ ng/dL}$)

An arterial blood gas analysis obtained on room air reveals:
pH: $7.37$
$\text{PaCO}_2$: $56\text{ mmHg}$
$\text{PaO}_2$: $60\text{ mmHg}$
$\text{HCO}_3^-$: $31\text{ mEq/L}$

Which of the following is the most appropriate next step in the diagnostic evaluation or management of this patient?

A 71-year-old man is transported to the emergency department from a local nursing facility due to the sudden onset of severe breathlessness and orthopnea that started 3 hours ago. He has a past medical history of severe chronic obstructive pulmonary disease (COPD) and ischemic cardiomyopathy with a left ventricular ejection fraction of $30\%$.

Upon arrival, he is visibly agitated and using accessory muscles of respiration. Vital signs are:
- Temperature: $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$)
- Blood pressure: $172/100\text{ mm Hg}$
- Heart rate: $118\text{/min}$ and regular
- Respiratory rate: $29\text{/min}$
- Oxygen saturation: $82\%$ on ambient air

Physical examination reveals jugular venous distention when sitting upright at 45 degrees. Chest auscultation demonstrates widespread expiratory wheezing mixed with fine bibasilar crackles. Cardiac auscultation reveals tachycardia and a prominent third heart sound (S3). There is 2+ bilateral pitting edema up to the knees.

Arterial blood gas analysis on ambient air shows:
- pH: 7.22
- $PaCO_2$: $75\text{ mm Hg}$
- $PaO_2$: $48\text{ mm Hg}$
- $HCO_3^-$: $31\text{ mEq/L}$

Which of the following are the most appropriate initial steps in the management of this patient? (Select exactly two)

A 72-year-old man with a history of chronic obstructive pulmonary disease (COPD) and hypertension is brought to the emergency department for severe, worsening shortness of breath over the past 24 hours. He reports that his breathing is especially difficult when he lies down to sleep, forcing him to sleep in a recliner chair. He denies fever, chills, or any change in the volume or color of his sputum. Blood pressure is 155/92 mm Hg, pulse is 108/min, and respirations are 26/min. Pulse oximetry shows 88% on room air. Physical examination reveals distended jugular veins, bilateral crackles at the lung bases, and an S3 gallop. There is 2+ bilateral lower extremity pitting edema.

Arterial blood gas analysis on room air shows:

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

A $64$-year-old woman is evaluated in the emergency department for severe shortness of breath and increasing leg swelling over the past week. She has a history of severe chronic obstructive pulmonary disease (COPD) requiring home oxygen therapy. Her temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), blood pressure is $105/68\text{ mm Hg}$, pulse is $118\text{ /min}$, and respirations are $28\text{ /min}$. Jugular venous pulsation is visible at $15\text{ cm H}_2\text{O}$. Cardiac examination reveals a prominent parasternal heave and a loud $P_2$. Lung auscultation shows significantly prolonged expiration and diffuse wheezing, with no crackles. The liver edge is palpable $4\text{ cm}$ below the right costal margin and is tender. Moderate pitting edema is present in the lower extremities. Arterial blood gas on $2\text{ L/min}$ supplemental oxygen shows:

pH: $7.31$
$PaCO_2$: $62\text{ mm Hg}$
$PaO_2$: $54\text{ mm Hg}$
$HCO_3^-$: $31\text{ mEq/L}$

A trial of non-invasive positive pressure ventilation (NIPPV) is initiated for acute-on-chronic hypercapnic respiratory failure. Ten minutes later, the patient becomes lethargic and her blood pressure drops precipitously to $70/40\text{ mm Hg}$. Which of the following is the most appropriate immediate next step in management?

A $72$-year-old woman is brought to the emergency department for sudden-onset severe shortness of breath, lightheadedness, and right-sided chest pain. She recently returned from a $12$-hour international flight two days ago. Her medical history includes moderate chronic obstructive pulmonary disease (COPD) and hypertension.

On arrival, she is somnolent but arousable. Temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), blood pressure is $82/50\text{ mm Hg}$, pulse is $118/\text{min}$, and respirations are $28/\text{min}$. Oxygen saturation is $85\%$ on room air.

Physical examination reveals elevated jugular venous pressure. Lung auscultation is clear bilaterally.

Bedside transthoracic echocardiography demonstrates a severely enlarged right ventricle with hypokinesis of the free wall and normal apical contraction. The left ventricle is small and hyperdynamic.

An arterial blood gas on room air shows:
pH: $7.29$
$\text{PaCO}_2$: $26\text{ mm Hg}$
$\text{PaO}_2$: $54\text{ mm Hg}$
$\text{HCO}_3^-$: $12\text{ mEq/L}$

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

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?

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)

During morning multidisciplinary rounds in the intensive care unit, the team evaluates a 73-year-old male who has been mechanically ventilated for the past $48$ hours. His initial presentation involved profound hypoxemia due to community-acquired pneumonia. The patient's medical history includes ischemic cardiomyopathy (left ventricular ejection fraction of $25\%$) and severe emphysema.

He was empirically started on intravenous vancomycin and piperacillin-tazobactam. The microbiology laboratory has just finalized the results of blood and bronchoalveolar lavage fluid cultures obtained at admission; both demonstrate heavy growth of *Streptococcus pneumoniae*. The susceptibility report confirms the isolate is sensitive to all tested antibiotics, including ceftriaxone and penicillin.

Vital signs reveal a heart rate of $112$/min and a blood pressure of $118/72$ mm Hg. He is afebrile. Physical examination shows engorged neck veins when the head of the bed is elevated. Cardiac auscultation identifies a third heart sound (S3). Lung examination yields diffuse bilateral crepitations that extend to the mid-apices, accompanied by prolonged expiratory wheezing.

An arterial blood gas analysis on current ventilator settings reveals:
- pH: $7.18$
- pCO $_2$: $56$ mm Hg
- pO $_2$: $82$ mm Hg
- HCO $_3^-$: $20$ mEq/L

Which of the following interventions are appropriate for this patient at this time? (Select all that apply)

A 22-year-old woman with a history of type 1 diabetes mellitus is admitted to the intensive care unit with a two-day history of high fever, productive cough, and progressive lethargy. She has been unable to tolerate oral intake and missed her last four doses of insulin. On arrival, her temperature is $38.9^\circ\text{C}$ ($102^\circ\text{F}$), pulse is $132\text{/min}$, respiratory rate is $36\text{/min}$, and blood pressure is $88/54\text{ mm Hg}$. Oxygen saturation is $89\%$ on ambient air. Physical examination reveals deep, rapid breathing and bronchial breath sounds with crackles in the right lower lung field. Laboratory studies show a serum glucose of $510\text{ mg/dL}$, sodium of $134\text{ mEq/L}$, potassium of $4.9\text{ mEq/L}$, chloride of $98\text{ mEq/L}$, and bicarbonate of $10\text{ mEq/L}$. A chest radiograph confirms a right lower lobe consolidation. The patient is resuscitated with intravenous normal saline, started on a continuous insulin infusion, and administered intravenous ceftriaxone and azithromycin. Two hours later, her respiratory effort wanes and she becomes severely hypoxemic, necessitating endotracheal intubation. She is placed on volume assist-control mechanical ventilation with a tidal volume of $400\text{ mL}$, a respiratory rate of $14\text{/min}$, $FiO_2$ of $0.70$, and positive end-expiratory pressure (PEEP) of $5\text{ cm }H_2O$. Thirty minutes later, arterial blood gas analysis reveals:

$pH$: $7.15$
$PaCO_2$: $38\text{ mm Hg}$
$PaO_2$: $72\text{ mm Hg}$
$HCO_3^-$: $10\text{ mEq/L}$

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

A 34-year-old woman with no significant past medical history is evaluated in the clinic for a 6-month history of progressively worsening exertional dyspnea and fatigue. She has no cough, wheezing, orthopnea, or leg swelling. She does not smoke. Vital signs are within normal limits. Physical examination reveals a prominent right ventricular heave, a loud pulmonic component of the second heart sound (P2), and a faint holosystolic murmur at the left lower sternal border that increases in intensity with inspiration. The lungs are clear to auscultation bilaterally. Electrocardiogram shows right axis deviation and right ventricular hypertrophy. Suspecting a primary pulmonary vascular disorder, the physician plans a comprehensive diagnostic workup.

Arrange the following diagnostic and management steps in the correct chronological sequence according to consensus guidelines for unexplained pulmonary hypertension, moving from initial screening to definitive management:

A $64$-year-old male construction worker presents to the emergency department for escalating breathlessness and a productive cough over the past three days. He notes that his baseline morning cough has worsened, and he is now producing thick, yellow-green sputum. His past medical history is significant for severe chronic obstructive pulmonary disease (COPD) and essential hypertension. He is currently compliant with a daily tiotropium inhaler. Vital signs demonstrate a temperature of $37.5^\circ\text{C}$ ($99.5^\circ\text{F}$), blood pressure of $132/84$ mmHg, heart rate of $94$/min, and respiratory rate of $24$/min. Pulse oximetry shows an oxygen saturation of $91\%$ on room air. Chest auscultation reveals prominent bilateral expiratory wheezing with a prolonged expiratory phase. There are no crackles. The jugular venous pressure is normal, and there is no lower extremity edema. Which of the following is the most appropriate pharmacological management for this patient?

A 26-year-old man is evaluated in the emergency department for severe shortness of breath that has progressively worsened over the past 48 hours. He has a lifelong history of asthma and uses a short-acting bronchodilator as needed. Yesterday, he moved into an apartment with a roommate who owns a cat. On arrival, the patient is fully alert but speaks in short, two-word sentences. Initial vital signs include a temperature of 37.1°C ($98.8$°F), blood pressure of 135/82 mmHg, pulse of 122/min, and respiratory rate of 30/min. Pulse oximetry shows an oxygen saturation of 93% on room air. Physical examination demonstrates prominent accessory muscle use and loud, diffuse expiratory wheezing.

He is immediately treated with continuous nebulized albuterol, ipratropium, and intravenous methylprednisolone. Two hours later, the nurse urgently alerts the physician because the patient has become drowsy and is difficult to rouse. Repeat vital signs show a blood pressure of 108/65 mmHg, pulse of 138/min, and a respiratory rate of 12/min. Oxygen saturation is 87% on 4 L/min via nasal cannula. Repeat chest auscultation reveals markedly diminished breath sounds bilaterally with absent wheezing.

An arterial blood gas analysis on the current oxygen setting shows:

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

A 32-year-old woman presents to the outpatient clinic with a 1-day history of right-sided pleuritic chest pain and mild dyspnea. Her vital signs show a temperature of 37.1°C (98.8°F), pulse of 92/min, respiratory rate of 16/min, and blood pressure of 118/76 mm Hg. Oxygen saturation is 99% on room air. She has no history of venous thromboembolism, recent surgery, or immobilization. Her physical examination is unremarkable. Arrange the following diagnostic steps in the most appropriate sequential order for the evaluation of this patient.

A 59-year-old woman is evaluated on hospital day 3 for new-onset respiratory distress. She was initially admitted for pyelonephritis complicated by septic shock and received 4 liters of intravenous crystalloid fluids over the first 24 hours. Blood cultures drawn on admission grew *Escherichia coli* that is susceptible to ceftriaxone, ciprofloxacin, and ampicillin. She has a history of type 2 diabetes mellitus and hypertension. Current medications include intravenous piperacillin-tazobactam.

Temperature is 37.2°C (99.0°F), blood pressure is 142/86 mmHg, heart rate is 112/min, and respiratory rate is 28/min. Pulse oximetry is 88% on room air. Physical examination reveals jugular venous distention to 11 cm H2O. Lung auscultation demonstrates bilateral crackles extending to the mid-scapulae and diffuse expiratory wheezes.

Arterial blood gas analysis on room air reveals:
pH: 7.25
PaCO2: 42 mmHg
PaO2: 56 mmHg
HCO3-: 18 mEq/L

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

A 68-year-old male retired teacher comes to the urgent care clinic complaining of a three-day history of increased shortness of breath and a persistent cough. He states his normally clear sputum has become thick and yellow. His medical history includes hypertension and a 45-pack-year smoking habit. He currently takes amlodipine. His temperature is 37.2°C (99.0°F), blood pressure is 134/82 mmHg, heart rate is 94/min, and respiratory rate is 24/min. Pulse oximetry reveals an oxygen saturation of 90% on room air. On auscultation, there is a prolonged expiratory phase with diffuse bilateral wheezing. Jugular venous distention is absent, and there is no dependent edema. A bedside arterial blood gas analysis on room air shows:

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

A 74-year-old male farmer is brought to the emergency department by his wife due to a 3-day history of progressively worsening shortness of breath, increased cough frequency, and a change in his sputum from clear to thick yellowish-green. He has a 45-pack-year smoking history and uses an albuterol inhaler as needed. Upon arrival, his temperature is $37.7^\circ\text{C}$ ($99.9^\circ\text{F}$), blood pressure is $145/88\text{ mmHg}$, pulse is $114/\text{min}$, and respiratory rate is $26/\text{min}$. Pulse oximetry shows an oxygen saturation of $85\%$ on room air. Physical examination reveals an anxious, mildly somnolent patient who is easily arousable and follows commands. He is using accessory muscles of respiration. Auscultation demonstrates globally diminished breath sounds with a prolonged expiratory phase and diffuse expiratory wheezing. Jugular venous pressure is normal, and there is no lower extremity edema. An arterial blood gas drawn on room air reveals:

Which of the following are appropriate initial management steps for this patient? (Select all that apply)

A 78-year-old man with end-stage idiopathic pulmonary fibrosis is admitted to the intensive care unit and intubated for acute respiratory failure. He is currently deeply sedated and unresponsive. His arterial blood gas reveals a pH of $7.21$, $PaCO_2$ of $68$ mmHg, and $HCO_3^-$ of $26$ mEq/L. The medical team determines his fibrotic lung disease is irreversible and he cannot be successfully weaned from mechanical ventilation.

The patient's medical record contains a valid advance directive clearly appointing his daughter as his sole healthcare proxy. The directive states he does not wish to be kept on life support if his condition is irreversible. However, the patient's son has just arrived at the hospital, disagrees with the daughter, and demands the team perform a tracheostomy and immediately start empirical intravenous meropenem and vancomycin to 'prevent any potential infections.' The patient has no fever, normal white blood cell count, and clear tracheal secretions.

Which of the following actions by the critical care physician are appropriate? (Select all that apply)

A $68$-year-old male is evaluated in the intensive care unit for altered mental status. He was admitted $4$ days ago for an acute exacerbation of chronic obstructive pulmonary disease (COPD) and acute decompensated heart failure. His initial treatment included noninvasive positive pressure ventilation, intravenous furosemide, and a $5$-day course of azithromycin and ceftriaxone, which he completed yesterday. He has a history of severe COPD, heart failure with preserved ejection fraction, and hypertension.

Over the past $24$ hours, he has become increasingly lethargic and is currently difficult to arouse. He is receiving oxygen at $2 \text{ L/min}$ via nasal cannula. Temperature is $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), blood pressure is $105/60 \text{ mm Hg}$, pulse is $108/\text{min}$, and respirations are $9/\text{min}$. Physical examination shows flat jugular veins when supine. Mucous membranes are dry. Cardiopulmonary examination reveals distant heart sounds and decreased breath sounds bilaterally without wheezing or crackles. There is no lower extremity edema.

Laboratory results are as follows:

Arterial blood gas analysis on $2 \text{ L/min}$ nasal cannula:

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