Oxygenation of patients undergoing ophthalmic surgery under local anaesthesia.

The oxygenation of 30 patients undergoing elective ophthalmic surgery without sedation whilst breathing air was studied and was compared with two methods of oxygen supplementation. Arterial oxygen saturation, inspired and expired oxygen and carbon dioxide were analysed. The delivery of oxygen at 21.min-1 via nasal cannulae was shown to be superior to a method which directed oxygen from under the surgical drapes.