Evaluation of dynamic compliance of lungs and disturbances of breathing mechanics in patients following laryngectomy for carcinoma of the larynx.

Abstract

The purpose of study was to observe changes which may develop in the mechanics of breathing following laryngectomy in patients with carcinoma of the larynx as compared with the pre-operative conditions. The studies were carried out on a group of 29 patients, performing the measurements twice, i.e. before operation and after laryngectomy and tracheostomy. The measurements were done using a Godart Compliance-Test type 121 apparatus. The value of the coefficient of dynamic compliance of the lungs was determined together with the magnitude and type of work necessary to overcome respiratory resistance. It was found that after the operation the coefficient of dynamic compliance of the lungs increased by 63.7% while the total work of breathing decreased by 38.7% and the work necessary to overcome the elastic resistance of the lungs fell by 33.7% and that for overcoming the non-elastic resistance fell by 49.3%. The most significant changes in breathing mechanics observed after the operation concerned the ratio or breathing work necessary to overcome the non-elastic resistance to the total breathing work. This ratio was 43.35% pre-operatively and 34.11% post-operatively. The obtained results suggest that impairment of laryngeal patency caused by the tumour raises the breathing work and reduces the coefficient of dynamic compliance of the lungs due mainly to an increased non-elastic breathing resistance.