To the Editor: In the article entitled "Poliomyelitic Paralysis and Tonsillectomy Reconsidered" by Ravenholt, which appeared in the May issue of the American Journal of Diseases of Children, the author states that poliomyelitis patients were considered to have bulbar paralysis if there was difficulty in breathing. This implies that bulbar involvement is the sole cause of respiratory inadequacy in patients with poliomyelitis. Not only is it not the sole cause; it is not even the most common cause.
Respiratory inadequacy with poliomyelitis occurs most often in patients who have the spinal type of the disease. Neuronal damage of spinal cord anterior horn cells which contribute to the phrenic and intercostal nerves results in partial or complete paralysis of the muscles of respiration.
In bulbar poliomyelitis damage of the medullary respiratory center results in loss of the central regulation of breathing. Patients so involved have inadequacy of ventilation because of irregularity