Oxford Miniature Vaporiser output with reversed gas flows

This study was undertaken to investigate and calibrate the isoflurane output of an Oxford Miniature Vaporiser (OMV) draw-over vaporiser with reversed gas flows. Plenum or Boyles type machines have gas flowing left to right through the apparatus. Draw over anaesthesia systems, in contrast, traditionally have the carrier gas, air plus oxygen, flowing right to left through the vaporiser. There are a number of variations in the external design of the OMV vaporiser: 1) a back bar mounted draw-over vaporiser with 23-mm taper and left to right gas flow, 2) the Tri-Service with 22-mm taper and left to right gas flow, and 3) the traditional draw-over OMV with right to left gas flow with a variety of tapers. Non-uniformity leads to a variety of possible connections. The predictable output of the OMV vaporiser assumes the correct direction of gas flows for the device. There are many second hand right to left OMV vaporisers for sale to developing countries where the nuances of vaporiser orientation add unnecessarily to the desired simplicity of anaesthesia. A simple calibration scale for reversed gas flows through the OMV vaporiser would be useful.

Arrival and departure

As the small jet circled the dirt landing strip, I felt apprehensive. The briefing in Nairobi had been very detailed but hadn't really allayed my fears. I struggled with my emotions and too many unanswerable questions. Why was I going to Somalia in the middle of a civil war, a war about which I knew so very little? What were the risks and what did I hope to achieve?

Sevoflurane drawover anaesthesia with two Oxford Miniature Vaporizers in series

The output of sevoflurane from a drawover system utilizing two Oxford Miniature Vaporizers (OMVs) in series has been shown in bench-testing to be predictable. We have shown that adequate anaesthesia can be achieved with one vaporizer in most situations if an intravenous induction is used. Occasionally a second vaporizer is necessary to deepen the level of anaesthesia. For an inhalational technique to be successful it is necessary to use both vaporizers from the outset. Under these conditions, adequate operating conditions are easily produced. The method could be useful in field or military applications.

Anaesthesia and mitochondrial disease

Mitochondrial diseases, or encephalomyopathies, are an uncommon, heterogeneous group of disorders with variable clinical course and presentation. Many of these patients present for surgery, or undergo anaesthesia in the course of investigation of their illness. Unfortunately, little information exists on their management in anaesthetic texts and the literature. We report on the anaesthetic management of a paediatric patient with mitochondrial disease, and briefly discuss the pathophysiology and anaesthetic implications of these disorders.

Spinal anaesthesia for caesarean section in the Solomon Islands

Results were kept on 43 spinal anaesthetics performed for caesarean section in the Solomon Islands, a developing tropical country in the Pacific Ocean. A 25-gauge Quincke needle was used and either 2.5 ml of heavy bupivacaine 0.5% or 2.0-2.5 ml of plain bupivacaine 0.5% were injected. Hypotension down to 85 mmHg occurred in four patients and there were no spinal headaches. Five patients had to be given a general anaesthetic. We recommend this technique to other doctors working in the Pacific Islands.