Common Anesthesia Side Effects: What to Expect
General Anesthesia Side Effects and Complications
As a board-certified anesthesiologist, I’ve walked hundreds, if not thousands, of patients through the process of anesthesia, explaining to them how it works and what the possible side effects and complications might be. In this article, I will share with you what I tell my patients. I’ll give you the rundown on what to expect and how to prevent some potentially unpleasant after-effects.
Before going on, though, it might be helpful to distinguish a "side effect" from a "complication." A side effect is an annoying and perhaps unpleasant outcome that accompanies the desired effect of a treatment. However, side effects typically do not cause any lasting harm. For instance, weight gain is a side effect of certain medications. Once you go off the medication, however, the weight gain typically goes away.
A complication, on the other hand, is an undesirable outcome of a treatment that causes harm to the patient. Complications are sometimes avoidable and sometimes not, depending on any pre-existing conditions and other factors.
General anesthesia is the most frequently used anesthesia in surgery. General anesthesia puts you into a deep sleep so that you will not feel any pain or have any awareness of what’s happening. Since general anesthesia involves the use of IV and inhaled medicines to induce and maintain an unconscious state, it is not surprising that it is associated with side effects, and less commonly, complications. Given the significant changes induced by these powerful medications, though, the safety record of general anesthesia is particularly impressive.
Although the safety record is remarkable, side effects often cannot be avoided. Most people experience one or more of the most common anesthesia side effects.
Side Effect #1: Sore or Scratchy Throat
Many people report a scratchy or sore throat after anesthesia. This side effect is often the result of the anesthesiologist’s efforts to monitor and regulate your breathing when you’re under. Some anesthetized patients are able to breathe on their own while others require some intervention. Moreover, there are some surgeries, particularly those in the abdomen or chest, that require the muscles used to breath to stay relaxed and not contract. In those instances, you will absolutely need some external support to keep breathing.
In order to help you breathe or control breathing, the anesthesiologist can choose among several methods.
- Breathing tube. This is the most common method for abdominal, chest, brain, or other major surgery. The doctor will slide an endotracheal tube between the vocal cords and into your windpipe after you are unconscious. While this is usually an easy, gentle procedure, the back of the throat and the windpipe are super-sensitive areas. As a result, the insertion of the tube often causes a sore throat. It usually lasts just a day or two, can be relieved with lozenges and ice water, and then typically resolves on its own.
Anesthesiologist Placing a Breathing Tube
- Laryngeal Mask Airway (LMA). This is a soft rubber mask made to fit inside the back of the throat. There is an opening for oxygen to pass through that sits over the entrance to the windpipe. The LMA allows you to breathe on your own and can be used for surgeries on areas outside the body cavities. The LMA may be associated with a lower incidence of, or lower severity of sore throat, but sore throats still occur fairly frequently. (Side Note: Although an LMA sounds better, there are some factors that make it less desirable than an endotracheal tube, such as if you have acid reflux. Since the windpipe isn't blocked off from the esophagus, as it is with a breathing tube, acid could potentially enter the lungs if you have this condition. Likewise, obese patients have a tougher time getting sufficient oxygen under the influence of the anesthesia drugs. So if your anesthesiologist has to use a breathing tube there is usually a medically sound reason why.)
Regardless of the breathing device used, oxygen and the anesthesia gases still dry out the mucosa of the throat contributing to that sore, scratchy feeling.
What Does an Anesthesiologist Do?
Side Effect #2: Post-Operative Nausea and Vomiting (PONV)
One of the most dreaded side effects of general anesthesia is nausea followed by vomiting. It’s such a frequent side effect that it has its own name: post-operative nausea and vomiting, or PONV. The nausea is triggered in some way by how the anesthesia affects the brain centers and the gastrointestinal system.
Patients with the following characteristics are more prone to PONV:
- A history of motion sickness
- A personal or family history of PONV
Surgeries more likely to lead to PONV include:
- Any surgery lasting longer than 30 minutes
- Abdominal and gynecological surgeries
- Ear, nose, and throat surgeries
- Laparoscopic surgeries
- Breast surgery
- Eye surgery
- Some orthopedic surgery
This list would appear to include almost every kind of surgery. Even in the few kinds of surgery not included, there are additional, unavoidable factors such as the such as use of narcotic and gas medications that contribute to PONV. So if we can't change many of these risk factors, what can we do about this particularly unpleasant side effect?
How to Prevent PONV
- Talk to your doctors. Follow pre-op instructions about not eating. Tell your anesthesiologist or the pre-op nurse about your risk factors (they will probably ask anyway). Also be sure to follow post-op instructions to the letter.
- Acupressure relief bands. Some people say they have been helped by the acupressure relief bands that are sold over the counter. Bring one with you and ask that it be applied as soon as it is safe (usually after surgery, but sometimes before).
- Start slow and go easy. When you get home, even if you feel hungry, start slowly with eating. Start with soft, easy-to-digest foods. Eat little bits at a time—and wait to see how you feel before moving on to harder-to-digest meals.
- Liquid diet. Some people prefer to stay on liquid diets for the first day after anesthesia. If you have had abdominal or gastrointestinal surgery, your diet will be restricted as ordered by your surgeon and advanced at their discretion.
- Ginger. The herb is often recommended as another over-the-counter nausea reliever. Follow your post-op instructions, as well.
- Preventative medications. We can give prophylactic (preventative) medications to help reduce the risk of PONV. There are various drugs we can give alone or in combination, based on the level of risk and the risk/benefit ratio of each drug, because, yes, they have side effects, too. Sometimes, we can alter the type of anesthetic or the medications used if the risk is significant.
- Hydration. We also try to make sure you are properly hydrated, especially if you have gone a long period of time before your surgery without liquids.
Surgeons need to get the surgery done and cannot make significant alterations in procedure to avoid nausea and vomiting.
- Anti-nausea medication. Surgeons can, at your request, prescribe an anti-nausea medicine along with the pain medicine that you will be taking. If you are prone to nausea and vomiting from the anesthetic, there is a good chance that the narcotic pain meds will make you sick, as well. So ask your surgeon in pre-op (before you are too out of it to remember) to prescribe the anti-nausea medicine.
Side Effect #3: Confusion
When coming out of anesthesia in the recovery, most people experience a profound sense of confusion and disorientation. It takes a while for the brain to actually wake up, even after you are conscious. Most people don't remember much after the pre-op sedative has been given.
However, some people remain confused for days or weeks, or longer, after their surgery and anesthetic. This is an active field of study right now, called Post-Operative Cognitive Dysfunction (POCD). One interesting thing to note is that this effect doesn’t just occur with general anesthesia. Indeed, even patients who had other types of anesthesia that should not affect the brain profoundly have experienced POCD. It seems that other factors, such as the stresses of surgery and recovery on the body, may also play a role.
At this point we know only that older patients and patients of lower socio-economic status have a higher risk for POCD. Active and diligent research continues to try to pinpoint who is at risk, why it occurs, and what, if anything, can be done to prevent it.
Side Effect #4: Muscle Aches
Often, if muscle aches accompany a sore throat, patients become concerned that they have the flu or that they “caught” something in the hospital. However, rest assured that both muscle aches and sore throats are relatively common side effects.
Muscle aches result from one of the medicines used to relax or "paralyze" the muscles so as to make it easier to insert the breathing tube and perform the surgery. Succinylcholine causes the muscles to "fasiculate," or rapidly contract and relax. This response to the medication may make the muscles feel sore for a day or two after surgery.
Heating pads and tylenol can be used for symptom relief, if anything at all is needed. Ask your surgeon before taking medicines like aspirin or ibuprofen, as these can contribute to bleeding from recent surgical sites.
Muscle and joint soreness can also result from lying motionless on the operating bed for extended periods of time. Unlike normal sleep, your body can't even make minor positional adjustments while you are under anesthesia. If you have pre-existing problems with soreness or stiffness, tell your nurse and anesthesiologist. If it doesn't interfere with the surgery, they may be able to pad or support that area differently to try to help.
Side Effect #5: Itching
A curious side effect of narcotic pain medication (often used as part of the anesthetic) is itching. Most people complain of itching on their face, especially the tip of the nose. Sometimes, people will have significant, all-over body itching and believe they are having an allergic reaction—and it can be hard to tell the difference—but most of the time, it's just a side effect.
Luckily, Benadryl can easily treat this side effect. However, first make sure it's okay to take over-the-counter medicines with the prescriptions you have been given. In the hospital, patients can get a special medicine that block the receptor responsible for itching but not pain relief, which is even more effective.
Narcotics are routinely used during anesthetics to block pain receptors and often cannot be avoided. Tell you anesthesia provider if you have had this bothersome side effect in the past.
Side Effect #6: Emotional Outbursts
A rather curious and common, although less-researched, side effect of anesthesia is emotional displays or outbursts after awakening. It should be stressed that these displays of emotion are not under the patient's voluntary control. If you have one of these extreme emotional reactions, it will not be held against you in any way. We know it's the meds.
A young man may wake up combative and in "fight" mode. Very often, their occupation or background gives clues that this may be an issue. With certain patients, particularly those in the military, law enforcement, or former prison inmates, I make sure to have extra medication on hand in order to calm an overly aggressive emergence from anesthesia. Luckily, the patient’s aggression usually resolves in less than five minutes; as they wake up, they are able to “reorient” to where they are and settle down on their own. Even when someone is very agitated, I probably give a sedative less than 10% of the time and only if I feel the patient may hurt himself or someone else (I got thumped in the sternum pretty hard once, so I have the medication ready, just in case!).
Young women are more likely to fall at the other end of the spectrum. Women from puberty on seem more likely to wake up tearful and crying. When they are awake enough to talk, they cannot explain why they are crying, and they often report that they don't feel particularly sad. They just can't stop crying. If this happens, it usually lasts less than 15 or 30 minutes.
Anesthesia may sound potentially scary and unpleasant, but keep in mind that all medications have side effects. The very powerful, potent, anesthetic agents are certainly no exception. No one, not even your anesthesiologist, can predict how you will feel or which side effects you may experience. If you are having surgery, talk to the pre-op nurse or the anesthesiologist (or both) about any concerns that you have. They will be able to discuss all of the risks and benefits with you. Chances are, though, that even with the possibility of side effects, you will still likely decide to have your surgery with anesthesia—rather than without it!