The phrase “NPO After Midnight” is one of the most common in medicine. It is present not only in physician’s pre-operative orders, but repeated by nurses, ward secretaries and dietary workers. Indeed NPO, nil per os in latin, maybe one of the oldest phrases in the western medical lexicon. Where did the midnight part come from and does it still serve us and our patients? I believe it does not, and should be replaced by more meaningful, understandable and evidence-based instructions.
In the olden days, patients having almost every kind of elective surgery requiring general or regional anesthesia, even the most minor, were admitted to the hospital (the only kind of institution where surgery was performed) the night before the scheduled procedure. The nursing staff prepared them that evening in appropriate ways, for the morning procedure and understood that the goal of “NPO after midnight” was to ensure an empty stomach. Patients were taken to the OR in the morning directly from their ward rooms.
Nowadays, patients sleep at home or in a hotel the night before surgery, get up in the morning at an hour that only farmers and fisherman would find reasonable, and arrive at the hospital or surgery center several hours before their scheduled procedure. Many of these patients have been told by the surgeon’s office staff or the surgery center pre-op phone caller, “Be sure not to eat or drink anything after midnight.” I’m sure I’m not the only anesthesiologist to discover that my 7:30 a.m. patient, who slept barely 4 hours, had a substantial meal at 11:45 p.m., much of which is still settled uncomfortably in their stomach. When I ask if they normally eat at that hour, the reply is something like, “no but they told me nothing after midnight and I thought that would be my last meal for quite a while.” There may be an ominous truth to that, which of course is completely beyond the patient’s understanding. This never happened in the olden days, but that’s why we should not be living in the past and should adopt protocols that work in today’s world.
I try to call my patients the night before surgery, which is pretty much a routine in my group’s practice, and when we get to the NPO part, they often ask something like, “So I shouldn’t eat anything after midnight?” I reply, “You should have a regular dinner at the normal time, unless your surgeon has given you other special instructions, and then don’t eat anything after that. If you are thirsty anytime in the night, you can have water to drink. Please don’t eat or drink anything once you get up in the morning before coming.” If they are scheduled for later than the first case, I tell them they can have small sips of water until they leave home. Most of us who have patients scheduled for surgery after 3 p.m., tell them they can have a light breakfast before 7 a.m., but there are surgeons who, when cancelations of earlier cases occur, will be upset that these patients can’t be moved up into the mid morning slot. You have to know how much to trust your surgical schedule and the surgeons with whom you work.
In an upcoming article in the CSA Bulletin, Dr. Korpman points out how much, often unhelpful, influence surgeons and others have in these issues, and gives us a clear iteration of the ASA recommendations for fasting before elective anesthesia. These become almost irrelevant if the patient hears from the surgeon’s office staff and the facility staff that they should “not eat or drink after midnight.” It’s always best for an anesthesia provider to give the NPO instructions, but unfortunately that does not always happen. We have to improve the way patients receive this important information and the reasons for it. I would rather have the non-anesthesia advisors tell patients, “Don’t eat or drink anything after dinner,” and leave midnight for sleeping.