Gastric contents at induction of anaesthesia. Is a 4-hour fast necessary?

Br J Anaesth. 1983 Dec;55(12):1185-8. doi: 10.1093/bja/55.12.1185.


The study was undertaken to ascertain whether a light standard breakfast would influence the volume and median pH of gastric contents. Comparisons were obtained between a group of patients (n = 22) fasted overnight and a group (n = 23) allowed a light breakfast. There were no significant differences between the groups in respect of the volume of gastric contents aspirated, the median pH of the gastric contents or the number of patients with a pH of less than 3.0 unit.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Analgesics, Opioid
  • Anesthesia, General*
  • Fasting
  • Female
  • Food*
  • Humans
  • Hydrogen-Ion Concentration
  • Parasympatholytics
  • Preanesthetic Medication
  • Stomach / physiology*
  • Time Factors


  • Analgesics, Opioid
  • Parasympatholytics