Measurement of recovery from outpatient general anaesthesia with a simple ocular test

Measurements of extraocular muscle balance with a Maddox wing can be a useful clinical test of the rate of recovery from general anaesthesia. In 65 dental outpatients recovery was found to be most rapid in those patients given only nitrous oxide, oxygen, and halothane, whereas the previous administration of methohexitone, propanidid, or thiopentone for induction was associated with slower recovery. Recovery rates after methohexitone and propanidid were similar and rapid enough to confirm their choice for intravenous induction of anaesthesia in outpatients, but delayed recovery after thiopentone showed that this agent is best avoided in these circumstances.