Intra-abdominal hypertension can impact the respiratory system by causing which of the following?

Intra-abdominal hypertension can impact the respiratory system by causing which of the following?

• A. Increased lung compliance
• B. Decreased tidal volume
• C. Decreased airway pressures
• D. Increased chest wall flexibility

Answer: (B)

Elevated intra-abdominal pressure pushes the diaphragm upward, limiting how far the chest and lungs can expand on inspiration. With less diaphragmatic excursion, the lungs cannot take in as much air per breath, so the tidal volume decreases. This effect occurs because the respiratory system becomes less compliant overall and the diaphragm and chest wall have to work harder to achieve inspiration. In contrast, lung or chest wall compliance isn’t improved by this condition, and airway pressures tend to rise as the system becomes stiffer, not decrease.

Elevated intra-abdominal pressure pushes the diaphragm upward, limiting how far the chest and lungs can expand on inspiration. With less diaphragmatic excursion, the lungs cannot take in as much air per breath, so the tidal volume decreases. This effect occurs because the respiratory system becomes less compliant overall and the diaphragm and chest wall have to work harder to achieve inspiration. In contrast, lung or chest wall compliance isn’t improved by this condition, and airway pressures tend to rise as the system becomes stiffer, not decrease.