The diaphragm is important in respiration. Impairment of diaphragmatic function impacts pulmonary function.
The clinical findings are:
(1) worse if bilateral
(2) worse if complete
Clinical features:
(1) dyspnea, which is worse with exertion or when supine
(2) restrictive pattern in pulmonary function tests with decrease in vital capacity
(3) rapid shallow breathing
(4) paradoxical inward motion of the abdomen during inspiration
(5) reduction in maximal static inspiratory pressure
Examinations may include:
(1) imaging studies to determine the status of left and right hemidiaphragm (paralyzed side elevated) including motion
(2) compound motor action potential (CMAP) of the phrenic nerves
Complications in severe disease:
(1) cor pulmonale
(2) respiratory failure
