A 13-year-old boy with a history of asthma and seasonal allergies is currently using albuterol to manage his asthma symptoms. Recently, his use of albuterol increased from 1–2 days/week to 4 times/week over the past several weeks, though he does not experience his symptoms daily. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 74/min, and respiratory rate 14/min. His physical examination shows clear, bilateral breath sounds and normal heart sounds. What change should be made to his current treatment regimen?

Add formoterol + budesonide twice daily

A 28-year-old man makes an appointment with his general practitioner for a regular check-up. He has recently been diagnosed with asthma and was given a short-acting β2-agonist to use during acute exacerbations. He said he usually uses the medication 1–2 times per week. Which of the following is the most appropriate treatment in this case?

Inhaled corticosteroids should be added as controller therapy.

He should start using a short-acting β2-agonist every day, not just when he has symptoms.

Long-acting β2-agonists should be added to his treatment regimen.

Systemic corticosteroids should be added to his treatment regimen.

He should continue with current treatment.

A 23-year-old man presents to his physician's office with increasing breathlessness over the past one month. He was diagnosed with asthma when he was a child and has been able to keep his symptoms under control with a Ventolin inhaler. However, over the past year or so he has found that he gets out of breath on several occasions during the week. He wakes up at least once a week with breathlessness. He finds that he feels out of breath during his weekly football matches, which never used to happen before. He has to sit down and take a couple of puffs of his inhaler to feel better. He has no other pertinent history at this moment, except that he started on a new job painting houses about 5 months ago. His physical examination does not show anything significant. His peak expiratory flow rate during spirometry averages about 85% of the normal value, after conducting the test 3 times. Which of the following would be the next best step in management?

Methacholine bronchoprovocation test

Follow up spirometry in 2 months

A 24-year-old woman presents with episodic shortness of breath, chest tightness, and wheezing. She has noticed an increased frequency of such episodes in the spring season. She also has a history of urticaria. She has smoked a half pack of cigarettes per day over the last 5 years. Her mother also has similar symptoms. The physical exam is within normal limits. Which of the following findings is characteristic of her condition?

Decrease in forced expiratory volume in 1 second (FEV1) after methacholine

Decreased forced vital capacity (FVC) on pulmonary tests

Chest X-ray showing hyperinflation

A 20-year-old man comes to the physician because of recurrent episodes of shortness of breath and a nonproductive cough for the past 4 months. He has two episodes per week, which resolve spontaneously with rest. Twice a month, he wakes up at night with shortness of breath. His pulse is 73/min, respirations are 13/min, and blood pressure is 122/70 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. Physical examination shows no abnormalities. Spirometry shows an FVC of 95%, an FEV1:FVC ratio of 0.85, and an FEV1 of 81% of predicted. Which of the following is the most appropriate initial pharmacotherapy?

Mometasone inhaler and oral zafirlukast

Budesonide and formoterol inhaler

A 40-year-old man with persistent moderate asthma presents for a pulmonary function test. His ratio of forced expiratory volume in one second (FEV1) to forced vital capacity (FVC) is 0.69, and his FEV1 is 65% of his predicted values. What other findings can be expected in the remainder of his pulmonary function test?

Increase in fractional exhalation of nitric oxide

Decreased diffusion capacity of carbon monoxide (DLCO)

Decrease in FEV1 with albuterol

Decrease in total lung capacity

Increase in FEV1 with methacholine

Asthma management and exacerbations for USMLE Step 3: High-Yield Internal Medicine Lessons

Asthma Diagnosis - The Wheezing Workup

History & Physical: Look for classic triad: wheeze, cough (esp. nocturnal), dyspnea.
Pulmonary Function Tests (PFTs) / Spirometry:
- ↓ FEV₁/FVC ratio (< 0.7)
- Reversibility post-bronchodilator: ↑ FEV₁ by ≥ 12% AND ≥ 200 mL.
Peak Expiratory Flow (PEF): Useful for home monitoring; diurnal variation > 20% is suggestive.
Chest X-ray (CXR): Usually normal; rules out mimics.

Spirometry flow-volume loops: normal vs. obstructive pattern

⭐ Fractional Exhaled Nitric Oxide (FeNO): A high FeNO level (> 50 ppb) suggests eosinophilic airway inflammation, supporting an asthma diagnosis and predicting response to inhaled corticosteroids.

Stepwise Management - Climbing the Ladder

The goal is to use the minimum step required to maintain control. Treatment is escalated if symptoms persist and de-escalated if control is maintained for >3 months. The preferred approach (Track 1) uses ICS-formoterol as both controller and reliever.

ICS: Inhaled Corticosteroid (e.g., Budesonide, Fluticasone)
SABA: Short-Acting β2-Agonist (e.g., Albuterol)
LABA: Long-Acting β2-Agonist (e.g., Formoterol, Salmeterol)
LAMA: Long-Acting Muscarinic Antagonist (e.g., Tiotropium)

⭐ Exam Favorite: The biggest shift in recent GINA guidelines is the move away from SABA-only reliever therapy. As-needed low-dose ICS-formoterol is now the preferred reliever across all steps to reduce exacerbation risk.

Acute Exacerbation - Gasping for Air

Triggers: Viral URI (most common), allergens, air pollution, exercise.
Severity Assessment: Based on symptoms, PEF, and vitals.
- Mild-Moderate: PEF >40%, speaks in phrases.
- Severe: PEF <40%, speaks in words, accessory muscle use.
- Life-Threatening: Silent chest, confusion, cyanosis - impending respiratory failure.

⭐ A "normal" PaCO₂ in a tiring, tachypneic asthmatic is an ominous sign of impending hypercapnic respiratory failure. Prepare for intubation.

Tripod position and accessory muscle use in dyspnea

High‑Yield Points - ⚡ Biggest Takeaways

Asthma diagnosis hinges on demonstrating reversible airway obstruction with spirometry (>12% and 200 mL increase in FEV1).

Management is a stepwise approach: SABA PRN, then add a low-dose ICS, then a LABA.

Viral URIs are the most common trigger for acute exacerbations.

Treat exacerbations with systemic corticosteroids, high-dose SABA, and oxygen.

Aspirin-exacerbated respiratory disease (AERD) presents with asthma, nasal polyps, and aspirin/NSAID sensitivity.

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