Video Stethoscope???A Simple Method for Assuring Continuous Bilateral Lung Ventilation during Anesthesia

Abstract

Complications of endotracheal intubation and mechanical ventilation are infrequent but important causes of intraoperative morbidity and mortality. We have developed a simple method of monitoring the ventilation of both lungs during general anesthesia and have evaluated this technique in 25 patients undergoing surgery under general anesthesia. A small plastic electrocardiographic electrode casing fitted with a microphone was affixed to the skin overlying each hemithorax in a location where preliminary auscultation showed that breath sounds could be heard. The sounds from each microphone were amplified and displayed on an oscilloscope screen in an X-Y format. The patterns seen on the screen allowed easy identification of right mainstem intubation, esophageal intubation, or proper endotracheal tube placement. This preliminary study suggests that our technique is feasible and provides more information about the position of the endotracheal tube than presently used methods.