Diaphragmatic paralysis

It is the loss of movement of the diaphragm. The diaphragm is a dome-shaped muscle that separates the thoracic cavity from the abdominal cavity that inserts at the level of the dorsolumbar vertebrae, costal arches, and sternum. It has openings that allow the passage of the aorta, the esophagus and the vena cava.

Under normal conditions, during inspiration, the diaphragm moves downward allowing the lungs to fully expand, and during exhalation, the diaphragm rises to allow the lungs to empty of air. It is therefore the most important muscle of respiration. It is innervated by the phrenic nerve.

Diaphragmatic paralysis can be bilateral or, more often, unilateral.

How is it produced?

The most common causes of unilateral diaphragmatic paralysis are tumors, including lung cancer and idiopathic patients. Other causes include:

• Neurological diseases: Myelitis, Herpes zoster, Poliomyelitis, Amyotrophic Lateral Sclerosis (ALS).
• Trauma: thoracoabominal, childbirth, thoracic surgery.
• Compressions: Goiter, Aortic Aneurysm.
• Infections: Pneumonia, Tuberculosis.

The most frequent causes of bilateral paralysis are spinal cord diseases (ALS, poliomyelitis, Syringomyelia), peripheral neuropathies (Guillén-Barré disease, Diphtheria, Alcoholism, Trauma), and muscular diseases (Myotonic dystrophy, Polymyositis).

Symptoms

In healthy individuals, unilateral diaphragmatic paralysis is asymptomatic. In patients with chronic lung diseases, it tends to aggravate their respiratory symptoms. Bilateral paralyzes usually present with orthopnea and respiratory disorders during sleep, consequently causing daytime sleepiness.

Physical examination shows inward chest wall displacement on inspiration.

Diagnosis

The chest radiograph suggests the diagnosis by showing an elevated diaphragm (or both). It is not uncommon for it to be a chance finding on an X-ray that is requested from the patient for another reason.

The confirmatory diagnostic test is dynamic fluoroscopy that shows the paradoxical movement of the diaphragm during respiration (the diaphragm rises during inspiration, and falls during expiration).

Treatment

If the involvement is unilateral, it is generally not treated because it is usually asymptomatic. respiratory physiotherapy is also used to try to restore the functionalism of the diaphragm. In bilateral cases, it may be necessary to resort to surgery with diaphragmatic plication.