A patient with unilateral diaphragmatic paralysis would be MOST at risk for:

A patient with unilateral diaphragmatic paralysis would be MOST at risk for:

• A. Gastroesophageal reflux
• B. Cheyne Stokes breathing
• C. Hypoventilation
• D. Sleep disordered breathing during REM

Answer: (D)

During REM sleep the chest wall muscles are largely atonic, so breathing becomes heavily dependent on the diaphragm. If one half of the diaphragm is paralyzed, the able half must supply most of the inspiratory work, and REM’s reduced neuromuscular tone further limits ventilation. This combination commonly leads to hypoventilation with nocturnal desaturation, i.e., sleep-disordered breathing that is most evident during REM. Gastroesophageal reflux can occur with various conditions and isn’t specifically driven by unilateral diaphragmatic weakness. Cheyne-Stokes breathing is a pattern seen with central control issues like heart failure or brain injury, not typically linked to unilateral diaphragmatic paralysis. While overall hypoventilation can occur, the REM-related reduction in ventilatory reserve makes sleep-disordered breathing during REM the most likely finding.

During REM sleep the chest wall muscles are largely atonic, so breathing becomes heavily dependent on the diaphragm. If one half of the diaphragm is paralyzed, the able half must supply most of the inspiratory work, and REM’s reduced neuromuscular tone further limits ventilation. This combination commonly leads to hypoventilation with nocturnal desaturation, i.e., sleep-disordered breathing that is most evident during REM.

Gastroesophageal reflux can occur with various conditions and isn’t specifically driven by unilateral diaphragmatic weakness. Cheyne-Stokes breathing is a pattern seen with central control issues like heart failure or brain injury, not typically linked to unilateral diaphragmatic paralysis. While overall hypoventilation can occur, the REM-related reduction in ventilatory reserve makes sleep-disordered breathing during REM the most likely finding.