Why empty stomach before surgery

Before having an operation, it's likely that you'll be given either a local or a general anaesthetic. A local anaesthetic numbs the area being treated, so you do not feel any pain. A general anaesthetic makes you unconscious so you cannot feel anything and you're not aware of what's going on during the operation.

Usually, before having a general anaesthetic , you will not be allowed anything to eat or drink. This is because when the anaesthetic is used, your body's reflexes are temporarily stopped. If your stomach has food and drink in it, there's a risk of vomiting or bringing up food into your throat. If this happens, the food could get into your lungs and affect your breathing, as well as causing damage to your lungs.

The amount of time you have to go without food or drink fast before you have your operation will depend on the type of operation you're having. However, it is usually at least 6 hours for food, and 2 hours for fluids. You'll be told how long you must not eat or drink for before your operation. Of these, the rules about medications can be particularly confusing. Simply put, patients may be asked to stop taking some medications, but to continue taking others.

Additionally, they may actually be given a different medication right before surgery as part of an advanced pain management protocol. But for others, it's important that you keep taking them as usual. You may also get new medicines to take before surgery. In short, the instructions given to patients prior to surgery have been established for a patient's safety, according to Hoberg. They instructions also are designed to minimize risk, lower complications like infection and enhance a patient's recovery process.

Facebook Twitter Email. Maggie O'Neill Health Source. A heavier meal takes longer to digest and negates the effect of abstaining from food and drink prior to surgery. If your surgeon has said you should take your regular medications on the morning of your surgery, plan to do so with the smallest sip of water possible. Do not take your medication if the surgeon has not instructed you to do so.

If you are unsure, call the doctor's office or take them with you to the surgical center. Also, take care not to swallow water when you brush your teeth. For some patients, particularly those with diabetes, fasting can cause additional issues.

Talk to your surgeon about how they would like you to handle low blood sugar issues should they happen during your period of fasting. In the past, the eight- to hour rule wasn't necessarily based in science but was more of an educated guess about how long it would take to empty the stomach fully with some additional time built in to be sure.

That said, research in the last decade has been more scientific and has produced some interesting results. One study even said that drinking clear fluids up to two hours before anesthesia actually led to the stomach being more empty than fasting.

At this time, most surgeons and anesthesia providers are still recommending a fast—refraining from both foods and fluids—of at least six hours prior to anesthesia. As research continues, you can expect the guidelines for fasting to change based on clear evidence. In the meantime, your surgeon and anesthesia provider will give you clear instructions on what they want you to do in the hours before surgery. You should avoid it if possible. The American Society of Anesthesiologists says that gum chewing can significantly increase the production of saliva and the volume of liquids in the stomach, but that it shouldn't be enough to have to cancel a surgery.

However, they don't encourage gum chewing for patients undergoing procedures with anesthesia. It's a good idea to eat healthy, nutrient-rich foods in the days before surgery. Choose fresh fruits and vegetables as much as possible.

Avoid processed foods and red meats, since they can be difficult for your body to break down and may increase inflammation. It seems simple—don't eat before surgery to prevent problems. It is simple, but a truly amazing number of patients do not follow instructions when preparing for their surgery.

The risks of eating and drinking when you have been instructed not to do so are higher than you might imagine. It is important to avoid all food and drink at least eight hours prior to having anesthesia, as the alternative may be aspiration pneumonia or other serious complications after surgery if instructions are not followed. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life.

Drinking mL of clear fluid two hours before surgery has no effect on gastric fluid volume and pH in fasting and non-fasting obese patients. Can J Anaesth. American Society of Anesthesiologists. Chewing gum while fasting before surgery is safe, study finds. Published October 12, Cleveland Clinic.

Best ways to prepare yourself for surgery. Published April 14, Your Privacy Rights. To change or withdraw your consent choices for VerywellHealth.