Comparing Conventional Endotracheal Cuff Inflation to Commercially Available Syringe Device: A Randomised Open Label Study

Introduction and background: 

Endotracheal intubation constitutes a routine part in providing general anaesthesia in OR and care of critically ill patients in ICU .A critical function of the endotracheal tube cuff is to seal the airway, thus preventing aspiration of pharyngeal contents into the trachea and to ensure that there are no leaks past the cuff during positive pressure ventilation. Different cuffs exist, high-volume low-pressure cuffs are the most used ones. High pressures exerted by cuff on tracheal mucosa can lead to reduction in blood flow to tracheal wall. Cuff pressure should be sufficient to prevent aspiration at the same time without compromising the tracheal blood flow. ETT cuff pressure between 20 and 30 cmH2O is considered to be the standard (safe) ETT cuff pressure range.  Over inflation of cuff is associated with ischemia of tracheal wall mucosa, mucosal irritation, post operative sore throat, acquired laryngeal stenosis etc. Under inflation of cuff is associated with increases the risk of micro-aspirations and the passage of gastric contents and contaminated secretions of the oral cavity into the trachea; this potentially causing aspiration pneumonitis, accidental extubation and self extubation. Various methods of cuff inflation are present, stethoscope guided, palpation guided and audible leak guided method. Current practice widely followed at our institute is palpation guided technique. There are several commercial syringe devices available, designed for ETT cuff inflation with pressure values shown on the syringe device. The Cuffsure â„¢ syringe is a cuff inflation device, with a colour belt indicator showing safe cuff pressure range. The syringe is FDA approved for use in humans. 

Rationale of the study:

Numerous studies comparing different techniques for cuff inflation report a high incidence of cuff pressure out of range in a great proportion. Developing an objective way to inflate endotracheal cuff that is reasonable, simple, and accurate would be helpful. Further research examining objective methods is warranted.