A comparison of the effect of three anaesthetic techniques on postoperative arterial oxygenation in the elderly.

Ninety patients (age range 49--99 yr) with a fracture of the neck of the femur were anaesthetized by a technique using halothane in oxygen in a closed circuit, halothane and 66% nitrous oxide in oxygen in a Magill circuit or artificial ventilation with 66% nitrous oxide in oxygen ("IPPV group"). In all three groups, there was a small decrease in PaO2 from an overall mean of 9.07 kPa before operation to 8.13 kPa at 60 min after anaesthesia. There was no significant difference between the groups in respect of the decrease; it was concluded that closed-circuit halothane in oxygen anaesthesia for this type of surgery was not accompanied by a significant degree of absorption collapse.