Preoperative fasting in healthy adults

Healthy is defined as ASA I-II without gastrointestinal disease or disorders.

Please note: the letters indicated in brackets on this page refer to the relevant classifications in the Grading Scheme.

The intake of oral fluids during a restricted fasting period

  • Intake of water up to two hours before induction of anaesthesia for elective surgery is safe in healthy adults, and improves patient wellbeing [A]
  • Apple juice and newsprintOther clear fluid (i.e. one through which newsprint can be read), clear tea and black coffee (without milk) can be taken up to two hours before induction of anaesthesia in healthy adults [A]
  • Tea and coffee with milk are acceptable up to six hours before induction of anaesthesia [B]
  • The volume of administered fluids does not appear to have an impact on patients' residual gastric volume and gastric pH,when compared to a standard fasting regimen. Therefore, patients may have unlimited amounts of water and other clear fluid up to two hours before induction of anaesthesia. [A]

The intake of solid foods during a restricted fasting period

  • A minimum preoperative fasting time of six hours is recommended for food (solids and milk). [D]

Chewing gum and sweets during a restricted fasting period

  • Chewing gum should not be permitted on the day of surgery [B]
  • Sweets are solid food. A minimum preoperative fasting time of six hours is recommended. [D]

Pharmacological interventions

Concurrent medications

  • Regular medication taken orally should be continued preoperatively unless there is advice to the contrary [D(GPP)]
  • Up to 30 ml water (2 tablespoons) may be given orally to help patients take their medication. [D(GPP)]

Premedication

  • Administration of premedication as currently practised, for example benzodiazepines, does not appear to affect the fasting recommendations for water and other clear fluid. [A]

Histamine-2 receptor antagonists (H2RAs)

  • The routine use of H2-receptor antagonists (H2RAs) is not recommended for healthy adults. [D]

Delayed operations

  • If an elective operation is delayed, consideration should be made to giving the patient a drink of water to prevent excessive thirst and dehydration. [D(GPP)]

For further information on the above grading classifications see Grading Scheme.