Correspondence

Abstract

A Y-piece is inserted s o r l5cm before the respirator control, one limb of which is occluded by a normal 0 . 5~1 gas tap. This enables the respirator to be turned on and off without switching the con pressor, which is normally located outside the theatre to lessen noise. A Vitalograp condenser humidifier is placed between the patient and the respirator. Tested against a 'dummy lung' with a n 8mm endotracheal tube and a compliance c 50ml/cm H 2O gauge the output of the EMO is 0.5 % higher than indicated at the 3 mark with a minute volume of 6 litresimin reducing to plus 0.4% at 10 litres/min.