If you or your loved one has needed to go for surgery, you are told not to eat or drink anything from the night before your surgery. In some cases, you are permitted to have clear liquids only.
Why are we told to do this?
Research has shown that having a meal or non-clear fluid or alcohol preoperatively (prior to anesthesia) has caused pulmonary aspiration (food enters the lungs and windpipe), nausea, vomiting, and has increased risk of choking.
In 2011, American Society of Anesthesiologists (ASA) published guidelines which allowed patients to have clear liquids up to 2 hours before surgery requiring anesthesia (general, regional or sedation).
Why clear liquids?
Clear liquids are permitted because of the way our stomach’s digestion system operates. Clear liquids do not put a strain on the stomach and intestines because it is predominantly made up of carbohydrates and has minimal amount of protein and fat.
Some examples of clear liquids discussed in the literature are water (flavoured water (e.g., Gatorade), carbonated water), coffee or tea (without milk or sweeteners) and apple or orange juice (without pulp).
Encouraging clear liquids can serve two important roles: it can help patients’ feel less dehydrated or decrease the risk of hypoglycemia (blood glucose lower than normal) and can increase patient satisfaction. For example, in cases when surgeries get postponed or cancelled, patients might not be very pleased with continuation of fasting from the night before their scheduled procedure, the clear liquid intake in this scenario serves almost like a buffer.
*This post is not medical advice. Please speak to your doctor to find if clear liquids are safe to ingest before your surgery.
