Fasting guidelines of international anesthesia societies
|Country, year||Fasting requirements at time of induction||Comments|
|American Society of Anesthesiologists, 2011||* 2 hours clear liquids||Healthy patients, elective surgery, pregnant patients not in labor|
|6 hours nonhuman milk, light meal||Light meal defined as toast or cereal with clear liquid|
|8 hours or more fried or fatty food or meat|
|European Society of Anesthesiology, 2011||2 hours clear liquids|
|6 hours solid food|
Chewing gum and sucking hard candy allowed up until time of induction Applies to patients with obesity, diabetes, GERD, nonlaboring pregnant patients Encourages oral fluid up to 2 hours prior to induction
|Canadian Anesthesiologists' Society, 2014||2 hours clear liquids|
|6 hours light meal or nonhuman milk|
|8 hours meat, fried or fatty food|
|Association of Anaesthetists in Great Britain and Ireland, 2001||2 hours clear liquids||Gum chewing should be treated as clear|
|6 hours solid food and nonhuman milk|
|Scandinavian Society of Anaesthesiology and Intensive Care Medicine, 2005||2 hours clear liquids||Up to 1 hour prior to induction, 150 mL water|
|6 hours solid food and milk|
|2 hours chewing gum and any form of tobacco|
2 hours for preoperative carbohydrate drinks intended for preoperative nutrition
|German Society of Anesthesiology and Intensive Care, 2008||2 hours clear liquids|
|6 hours meal|
ASA Summary of Fasting Recommendations
|Ingested Material||Minimum Fasting Period|
|Clear liquids||2 h|
|Breast milk||4 h|
|Infant formula||6 h|
|Nonhuman milk||6 h|
|Light meal||6 h|
These recommendations apply to healthy patients who are undergoing elective procedures.
They are not intended for women in labor.
Following the Guidelines does not guarantee complete gastric emptying.
The fasting periods noted above apply to patients of all ages.
- Examples of clear liquids include water, fruit juices without pulp, carbonated beverages, clear tea, and black coffee.
- Because nonhuman milk is similar to solids in gastric emptying time, the amount ingested must be considered when determining an appropriate fasting period.
- light meal typically consists of toast and clear liquids.
- Meals that include fried or fatty foods or meat may prolong gastric emptying time. Additional fasting time (e.g., 8 h or more) may be needed in these cases. Both the amount and type of food ingested must be considered when determining an appropriate fasting period.