Halothane consumption under varying breathing circuit designs.

Thirty one patients at the Eldoret District Hospital, currently being used as a referral and teaching hospital, were anaesthetised and allowed to breathe through any of the three standard Maplesons circuits. The quantity of halothane required to maintain a satisfactory level of anaesthesia was measured and expressed in millilitres per kilogramme body weight, per minute. This value was used to compare the cost-effectiveness of the three circuits under different modes of ventilation.