How Long Is Long Enough? If you\’ve ever undergone surgery, you probably received the traditional pre-op order: Don\’t eat or drink anything after midnight prior to the day of surgery. Some experts agree that the length of the recommended fast is needlessly long. Fasting guidelines have been relaxed in recent years, but it\’s not uncommon for patients to be given the traditional after-midnight order. While it\’s always best to
follow your doctor\’s advice, it\’s perfectly reasonable to ask about relaxing the fasting requirements especially if you\’re scheduled for an afternoon procedure. In that case, you might be asked to go without food for more than 12 hours! Doctors and anesthesiologists are often willing to accommodate your wishes. The after-midnight order has been the norm for decades. It\’s a precautionary measure to prevent pulmonary aspiration, which occurs when stomach contents enter the lungs, potentially blocking airflow and putting patients at risk for serious infections like pneumonia. However, modern anesthesia techniques make pulmonary aspiration much less likely. And when it does happen, it almost never results in long-term complications or death.
What\’s more, research has demonstrated that the stomach empties much faster than previously believed, and a long fasting period probably won\’t reduce aspiration any better than a short fast. A long fast may add to discomfort during recovery. Fasting can lead to headaches, nausea, dizziness and dehydration. Dehydration can be serious and makes it difficult for nurses to draw blood for necessary tests. In its preoperative fasting guidelines, the American Society of Anesthesiologists says it\’s safe for healthy people of all ages Clear liquids, including water, clear tea, black coffee, carbonated beverages and fruit juice without pulp, up to two hours before surgery Very light meals, like toast and tea with milk, up to six hours before surgery Heavy meals, including fried or fatty foods and meat, up to eight hours before surgery Despite these guidelines, don\’t be surprised if you schedule an elective procedure and are given after-midnight instructions. Many surgeons and hospitals continue to recommend the traditional after-midnight order on the assumption that it\’s easier to give everyone the same instructions.
Therefore, patients don\’t need to count down the hours before surgery when making decisions about what to eat or drink, and health care professionals don\’t need to sort out which patients should have different fasting times. Some patients do need to follow the after-midnight rule. These include people who have gastroesophageal reflux disease (GERD) and people with gastric paresis (paralysis of the stomach that can occur in people who have diabetes). These individuals have an increased risk of vomiting and aspiration during surgery and should be instructed to fast for a longer period as should people undergoing gastric or intestinal surgeries. A blanket after-midnight order protects people who might have undiagnosed GERD or diabetes. Source: Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50 Q. Is it really necessary to prevent patients from drinking water for many hours before surgery? A. The well-known rule that a preoperative patient should have Бnothing by mouth after midnightБ was not based on scientific evidence, and many medical organizations now have more flexible guidelines.
For example, American Society of Anesthesiologists guidelines generally permit clear liquids until two hours before surgery. A ban on eating and drinking too close to the time of general anesthesia has a practical reason: to prevent aspiration of stomach contents, resulting in pneumonia. But it turns out that this problem is Бrare in healthy patients having elective surgery,Б according to a 2000 in the online journal Update in Anesthesia. The midnight cutoff was applied to both eating and drinking sometime in the 1960s, Бalthough the reasons for it have been lost in the mists of time,Б the authors wrote. Before that, clear liquids had long been permitted until two hours before surgery. In the 1980s, randomized double-blind studies were begun to find out how long it takes to empty the stomach after eating or drinking, and the effects on patients. A 2003 found that Бdrinking clear fluids up to a few hours before surgery did not increase the risk of regurgitation during or after surgeryБ and that drinking water actually reduced gastric volume. C. CLAIBORNE RAY