Preparing for Surgery
Hungry? Thirsty? It’s for your own good.
The time just before experiencing surgery or an invasive procedure is often accompanied by anxiety. The hospital gowns and feelings of nervousness are nearly unavoidable. Yet, some may ask, “Why can’t I eat or drink before my procedure?” The simple answer is for your safety, but a more detailed explanation may make the required period of fasting more tolerable.
Nearly all surgeries (and many procedures) involve the administration of medications. All medications have a desirable or intended effect. Unfortunately, medications also have side effects or effects beyond their primary purpose. Medications used for anesthesia or sedation are not exceptions.
Risk of Reflux
Technically, anesthesia is an induced condition of not feeling. More often, anesthesia is referred to as “being put out.” While an anesthetic may or may not involve being “put out,” it nearly always involves the administration of medications that partially or completely diminish the body’s reflexes. Without protective reflexes (such as coughing and gagging), it is possible for food or fluids consumed before surgery to “reflux” from the stomach into the esophagus. These partially digested materials may then pass down into the lungs. In the lungs, partially digested stomach contents can cause serious inflammation problems resulting in Asthma-like reactions, pneumonia, poor oxygen delivery to the brain or heart, or even death.
The potential for serious injuries is so high that people scheduled for surgeries or procedures requiring sedation are held “NPO” or without food, fluids and other substances such as chewing tobacco, gum or hard candy. While gum or chewing tobacco may not always be swallowed, they stimulate the production of saliva, which is swallowed. Smoking avoidance is also strongly recommended. Smoking delivers substances to the body, which then facilitates gastric fluid reflux into the esophagus and (again) cause problems in the lungs. Further, carbon monoxide from smoking aggressively “competes” with oxygen in the blood stream making less oxygen available to tissues. Tissues receiving less than maximal amounts of oxygen can be more extensively damaged in surgery, take longer to heal after surgery and are more likely to become infected.
The period of time people are asked to not eat, drink or smoke prior to surgery may vary with age and situation. Generally, there will be some period of fasting specified in your pre-procedure instructions. If you are unsure about what to do or have special considerations such as diabetes or other conditions effected by not eating or drinking for some period of time, contact your physician a few days prior to your procedure.
Lastly, if you make a mistake and eat or drink prior to your surgery or procedure, be honest with your health care providers. They would much rather you tell them about your mistake. Unfortunately, such mistakes may result in delaying or rescheduling your procedure. However, making an honest mistake like eating or drinking before your surgery should not jeopardize your health. In the end, everyone wants your procedure to go smoothly and for your recovery to go well.