It is common for doctors and surgeons to advise patients not to eat for at least eight hours prior to surgery and sometimes up to 12 hours. While this might sound excessive, there is a very good reason for it. Eating even a single cracker or taking a sip of water significantly increases the likelihood of complications during or after your surgery.
If you do have anything to eat or drink after midnight or the cut-off time given in your surgical instructions, we will need to cancel the procedure. Even if you are able to reschedule the surgery, it means you must go for a longer time with the pain or other issues that led to the recommendation for surgery in the first place.
Since most surgeries take place in the morning, you will likely be sleeping for a good portion of the time that you must fast from food and liquid. Depending on your specific surgery, it may be necessary to complete a bowel preparation procedure as well. This removes stool and food from the inside of your digestive tract to ensure that neither prevents you from receiving the surgery you need.
Why Not Eating Before Surgery is So Important
One of the biggest risks of having food or liquid in your stomach right before surgery is that it could lead to aspiration. Most people have had the experience of taking a bite of food or sip of liquid and having it go down the wrong tube or get stuck in the throat. Even though it’s unpleasant, your body will automatically trigger a coughing mechanism to keep you from choking or aspirating. You may also vomit or gag. This process can happen when you swallow saliva wrong as well.
Your body knows what to do when this situation happens while you are awake. However, it is a different story when you are in a deep sleep due to anesthesia. You are unconscious and your muscles are temporarily paralyzed, which means that your body cannot react in the same manner as when you are awake. Additionally, you have an endotracheal tube in your throat that increases the likelihood of aspiration. If it does happen, it will be difficult for the medical staff to detect.
Aspiration can also happen when you are not under anesthesia. This includes when you feel too weak or sick to cough, gag, or vomit in response to food, liquid, or saliva going down the wrong tube.
Another thing to consider is that nausea and vomiting are common after coming out of anesthesia after surgery. When food or liquid is in your stomach in an undigested state during surgery, it increases the likelihood that you will vomit during a deep sleep.
This can be very dangerous as you could inhale and draw the vomit into your lungs. It can even lead to a condition known as aspiration pneumonia. The fact that you are under anesthesia and have an endotracheal tube in your throat greatly increases the chances of this happening. You can feel rest assured that your nurse will provide you with medication for nausea or vomiting if you come out of surgery with these problems.
If you did need to complete bowel preparation, eating or drinking anything less than eight hours before your surgery will undo the procedure altogether. It would be a shame to go through all that for nothing.
Eating Choices in the Days Leading Up to Surgery
Eating a high-protein diet in the days or even weeks before surgery will help you heal faster after the procedure. Some good choices include low-fat dairy products, tofu, beans, chicken, pork, and seafood. We also recommend that you drink a lot of water to stay hydrated. You should produce urine that looks colorless and clear. Adequate water intake also helps to decrease aches and pains and increase your overall well-being. Getting enough to eat and drink before you need to fast will help you feel less hungry and thirsty when you cannot have anything.
Be sure to eat a light meal as the last thing you consume prior to surgery. Soup is a great option, while a heavy meal with a lot of fat will take longer for your body to digest.
Medications and Special Instructions for Diabetics
Your surgeon will let you know if you should take any of your regular medications on the day of surgery. If so, drink as little water as possible to get the pills down. You should refrain from taking your medication until after surgery unless your doctor or surgeon specifically tells you to do so. Additionally, use extra caution to ensure that you do not swallow any water when you brush your teeth.
If you have diabetes, fasting from all food and beverages could present challenges for blood sugar control. Your doctor or surgeon should discuss expectations for fasting with you in detail prior to your procedure. Please do not hesitate to ask if you feel unclear about this.
Please note, the information provided throughout this site is not intended or implied to be a substitute for professional medical advice, diagnosis or treatment. All content, including text, graphics, images, and video, on or available through this website is for general information purposes only. If you are experiencing related symptoms, please visit your doctor or call 9-1-1 in an emergency.