There was no evidence to suggest a shortened fluid fast results in an increased risk of aspiration, regurgitation or related morbidity compared with the standard 'nil by mouth from midnight' fasting policy. Permitting patients to drink water preoperatively resulted in significantly lower gastric volumes. Clinicians should be encouraged to appraise this evidence for themselves and when necessary adjust any remaining standard fasting policies (nil-by-mouth from midnight) for patients that are not considered 'at-risk' during anaesthesia.
Fluid deprivation before operation. The effect of a small drink.
The effect of oral fluids before operation, followed by intramuscular morphine, on gastric volume and pH was examined in 150 elective surgical patients, ASA physical status 1 and 2, who were randomly assigned to one of the three groups of 50 each. Group 1 (control) continued their overnight fast; patients in Groups 2 and 3 received 150 ml water 2 hours before the scheduled time of surgery. Patients in Group 3 received intramuscular morphine 0.15 mg/kg and promethazine 0.5 mg/kg one hour before operation. The residual gastric volume was obtained by suction and its volume and pH measured immediately after induction of anaesthesia. Statistically significant (p less than 0.05) decrease in residual gastric volume was observed in Groups 2 and 3 as compared to Group 1. However, the difference between these two groups was not statistically significant. There was no statistically significant difference in pH among the three groups. Overnight fluid fasting is not justified in elective surgical patients. Morphine can be safely given one hour before surgery in patients who have received water (150 ml) 2 hours before operation.