Intrapleural cough pressure in patients after thoracotomy

Quantitative studies of cough strength seem to be valuable in evaluating cough dynamics and the effectiveness of various procedures designed to raise the cough force. To evaluate cough strength in 20 patients after thoracotomy intrapleural cough pressures were measured with a balloon catheter inserted in the ipsilateral pleural space toward the apex. A balloon catheter designed to measure intraluminal esophageal pressure was used in this study. The balloon was inflated with 1 ml of air and the transmitted intrapleural pressure was measured during the maximum voluntary cough effort in the supine and/or sitting position. The pressure change during coughing seems to serve as an index in evaluating the strength of the respiratory muscles. It was observed that the cough pressure increased progressively following thoracotomy, and that it was higher in the sitting position than in the supine position. The most effective procedure to raise the maximum cough pressure was manually assisted compression of the chest wall in the sitting position during voluntary coughing. Epidural anesthesia following thoracotomy seemed to be effective in inducing higher cough pressure changes.