A simple method to control tracheal cuff pressure in anaesthesia and in air evacuation

The pressure within latex balloons remains constant despite the balloons be ing inflated to more than 40 times their initial volume. We used this prope rty to enable improved tracheal cuff pressure control. A latex balloon with an initial volume of 5 mi was connected via a vinyl duct attached with a r oller clamp and three-way stopcock to a standard tracheal tube cuff. The 5 mi latex balloon was then inflated with 250 mi of air. The pressure within the tracheal tube cuff was monitored throughout anaesthesia with the inflat ed latex balloon acting as a pressure controller. Throat symptoms were reco rded on the first four postoperative days. The controller kept the tracheal tube cuff pressures constant, and reduced the incidence of postoperative t hroat symptoms. Variations in cuff pressures with and without the controlle r were investigated in an altitude chamber to simulate flight. In the altit ude chamber, cuff pressure reached over 200 cmH(2)O at 10 000 feet without the controller, whereas such variations were practically eliminated when th e controller was used.