Ingestion of Clear Fluids Is Safe for Adolescents up to 3 H Before Anaesthesia

We have studied the effect of ingestion of unlimited clear fluids by adolescents up to 3 h before anaesthesia to determine the effect this fluid ingestion would have on thirst, hunger and gastric contents at induction of anaesthesia. We studied prospectively 152 adolescents (ages 13-19 yr) undergoing elective surgery. Fifty percent of the patients had nothing by mouth after midnight. The other 50 % were instructed to ingest unlimited clear fluids up to 3h before surgery. On arrival in the operating room, subjects were asked to assess thirst and hunger with a linear analogue scale of 0-10 (0 cor-responding to no thirst or no hunger). After induction of anaesthesia, gastric contents were aspirated via a 16-French gauge orogastric tube. Gastric fluid volume (GV) was measured with a syringe and gastric pH (GpH) was assessed with Merck pH strips. GV, GpH and subject hunger were unaffected by ingestion of clear fluids. Subject thirst was reduced by clear fluids. It is concluded that unlimited clear fluid ingestion by healthy adolescents up to 3 h before operation decreases thirst and does not affect gastric contents. KEY WORDS Anaesthesia • general. Gastrointestinal tract: gastric fluid volume, gastric pH, preoperative fluids. The ingestion of clear fluids by patients on the day of surgery is being reviewed [1-8]. There is no physiological evidence to support the guidelines suggesting 4-6 h abstention from clear fluids by healthy patients before elective surgery. It has been shown that healthy adults may ingest limited volumes (only 150 ml) of clear fluids up to 2-3 h before anaesthesia [7,8]. For adolescents, there is no evidence for or against the view that abstention from clear fluid is necessary on the day of surgery. Also, it has not been established if preoperative ingestion of clear fluids would benefit adolescents. This study was designed to determine if adolescents could ingest unlimited volumes of clear fluids up to 3 h before surgery without affecting gastric contents, and to determine if this would decrease patient thirst and hunger. Also, we wished to examine if the gastric content of adolescents was influenced by gender, age, weight and inpatient/outpatient status.