Immediate mucosal effects of short-term, soft-cuff, endotracheal intubation. A light and scanning electron microscopic study.

Little is known regarding the early pathogenesis of intubation-induced laryngotracheal damage or the effects of presently used soft-cuff endotracheal tubes. We have examined the pathological changes of short-term intubation (four hours) in six mongrel dogs. Interaction of the endotracheal tube with the mucosa produced a variety of lesions ranging from superficial abrasions to ulcerations with the most severe lesions in the respiratory epithelium. Changes are present at the free surfaces of ciliated cells that include flattening, fusion, and erosion of cilia of sufficient extent to compromise ciliary function. The ischemic and mechanical modes of injury are compared; the latter is considered causal with modern soft-cuff tubes. These studies reveal tube-induced mucosal damage of an extent and nature not previously appreciated.