What is the effect of diaphragmatic paralysis on the respiratory system?

Diaphragmatic paralysis has a significant impact on the respiratory system, primarily leading to impaired normal ventilation. The diaphragm is the primary muscle responsible for breathing, particularly during inhalation. When it is paralyzed, it cannot contract effectively, which diminishes the ability to generate negative pressure in the thoracic cavity necessary for normal inhalation. This results in reduced lung expansion and ultimately impaired ventilation—the process of moving air in and out of the lungs.

With compromised diaphragm function, patients may rely more on accessory muscles for breathing, which are less efficient. This can lead to inadequate gas exchange due to reduced air movement into the lungs and ventilation-perfusion mismatches. Overall, the inability of the diaphragm to function properly creates difficulties in maintaining adequate ventilation and oxygenation, impacting overall respiratory efficiency and leading to potential hypoxemia and hypercapnia.

This understanding underscores the critical role of the diaphragm in the respiratory process and highlights why its paralysis affects ventilation so severely.