Which patient is at highest risk for developing atelectasis?

• A. Neonate with respiratory distress syndrome
• B. Child after tonsillectomy
• C. Postoperative abdominal or thoracic surgery, immobile, smoker, elderly
• D. Young healthy athlete

Answer: (C)

Atelectasis arises when alveoli collapse due to inadequate ventilation, leading to reduced gas exchange. The postoperative abdominal or thoracic patient who is immobile, a smoker, and elderly is at the highest risk because multiple interacting factors stack up to impair lung expansion and clearance of secretions. Abdominal or chest incisions limit diaphragmatic movement and deep breathing due to pain, so tidal volumes drop and areas of the lung aren’t adequately ventilated. Immobility keeps the lungs from regularly inflating fully, allowing mucus to pool and plug small airways. Smoking further disrupts ciliary function and increases mucus production, making mucus clearance less efficient and promoting secretions that can block airways. Age brings decreased chest wall compliance and weaker cough effort, compounding the problem. Together, these elements create a scenario in which alveoli are more prone to collapse than in the other situations.

In contrast, a neonate with respiratory distress syndrome primarily faces a surfactant deficiency causing widespread alveolar collapse from a different mechanism, which is serious but not the same combination of post-op factors that most strongly predict atelectasis in an older patient. A tonsillectomy is less likely to cause significant shallow breathing or mucus plugging affecting large portions of the lungs, and a young healthy athlete typically has robust ventilation and clearance, making atelectasis much less likely.