The Ohmeda Universal PAC drawover apparatus. A technical and clinical evaluation.

The Ohmeda Universal PAC drawover apparatus, a modification of an earlier series of vapour-specific vaporizers, was assessed with regard to its output under varying gas flows and temperatures and its clinical usage with isoflurane and enflurane. The device tended to over-deliver vapour, particularly at low flows and at high temperatures. Its clinical performance during spontaneous and positive pressure ventilation was satisfactory, although adequate concentrations were not achieved using enflurane in the spontaneous ventilation mode. The device was not assessed with ether or halothane. The robust construction, relatively large capacity and thermocompensation make it suitable for field or military anaesthesia.