Frequently Asked Questions

Awareness

Why can't I alert anyone during surgery?

Patients under general anesthesia may be paralyzed by medications, with their breathing assisted by machine. This means they can’t talk or alert anyone through gestures.

What is awareness during general anesthesia?

"Awareness during general anesthesia" is unintentional consciousness or awareness of events happening during an operation either with or without pain sensations. A person may be physically unable to notify the doctors or nurses of awareness during the surgery, but might be able to hear conversations, statements, and experience other sensations related to the operation. This has also been called “recall during anesthesia” and “explicit awareness” by some authors. If you were supposed to be awake or just sedated for surgery, it is not “awareness during general anesthesia”. Awareness is to be expected at these times.

What types of anesthesia are there?

There are three types of anesthesia; local, regional, and general. Local anesthesia is specific; a small area of the body is numbed while one is conscious or awake. Regional anesthesia is administered to numb a specific region of nerves on the body. The patient may be awake/ conscious or receive a sedative for a light sleep during the operation. The patient may remember parts of the procedure, but should be free of pain. General anesthesia is a state of regulated unconsciousness that results in a loss of body sensation through anesthetic drugs, such as gases or vapors inhaled through a mask or breathing tube or drugs given through an IV. It is rare for patients to have any memory during a general anesthesia.

Why does “awareness during general anesthesia” occur?

Awareness could occur for a number of different reasons. It may be necessary to give fewer drugs during anesthesia if there are problems or complications. The risk of awareness may be weighted against the risk of life-threatening complications. Sometimes certain medications are necessary, but they can make it difficult for the anesthetic provider to monitor the depth of anesthesia. Drugs affect people in different ways. Some people may need more anesthesia than others to stay asleep and unaware. Unfortunately, there are other rare times that technical or human error occurs.

How often does “awareness during general anesthesia” occur?

Research suggests that for approximately 15 years the incidence rate for awareness during general anesthesia has been 0.1% to 0.4% (1-4 per 1000 patients). The exact frequency with which awareness during general anesthesia occurs is difficult to know because patients may not discuss their experience with health care providers. Avoidance of discussion about this problem can be a behavioral response that is either conscious or unconscious. Sometimes, patients have some lasting emotional or psychological consequences that occur after surgery, but do not know about the awareness until some time later.

How was I monitored during anesthesia?

Oxygen sensors, blood pressure, heart rate, anesthetic gas measurements, temperature, and breathing monitors are some of the ways the anesthetic provider monitored you during anesthesia. More recently, brain electrical activity monitoring (EEG) has been developed to measure more directly anesthesia depth.

How can I avoid/prevent “awareness during general anesthesia”?

Talking with your anesthetic provider is the most beneficial way to help prevent awareness during general anesthesia. During the preoperative meeting, you and your anesthesia provider should discuss your anesthesia options and select the best and safest treatment for you during your operation. At this time, you should be open and honest about your medical history, medication use, and lifestyle habits. Lifestyle habits may include but are not limited to alcohol and drug use.

Who should I tell if I experience “awareness during general anesthesia”?

An anesthesia provider, which includes the anesthesiologist or nurse anesthetist, or mental health providers, which includes counselor, psychiatrist, psychologist or social worker, and family and friends should hear about your awareness experience.

What should I tell the anesthetic provider about my “awareness during general anesthesia”?

You should be as open and honest as possible about your awareness during general anesthesia.  Talking about the experience will likely be difficult; however, the more information or descriptions you can recall from your surgery will be helpful.  This includes thoughts, feelings, and things you heard or smelled.

When should I tell them I have experienced “awareness during general anesthesia”?

When you inform your anesthesia providers of your awareness experience may depend on when you remember. If you have recall after the surgery, you should inform them during the postoperative meeting. If you have recall before the discharge meeting, you should inform them. If you have recall once you are home, you can either wait until your next health appointment or call to find out who you can speak with about your awareness during general anesthesia. If you experience a significant change in your mood, emotions or general feeling, you can speak with a health professional(s).

If I have more questions after my surgery, who should I contact?

Your anesthetic provider or health care provider should provide you with contact information.

What are the consequences of “awareness during general anesthesia”?

The consequences of awareness during general anesthesia vary from person to person. The continuum of consequences may be minor such as no psychological consequences or negative effects, to some level of psychological or emotional stress, anxiety, or effects, to a severe level of psychological or emotional injury. Some individuals are even diagnosed with posttraumatic stress disorder. The duration of the mental trauma can be from a few days or months, to years. Regardless of how much or little, or the length of time for psychological consequences, a person should talk with a health provider about his/her concerns.

Are teenagers more likely to experience awareness during general anesthesia?

The simple answer is that we do not know. Awareness is such an uncommon problem that a very large study would have to be done to understand how frequently it occurs in teens, and this kind of study has not been done.

Is it possible that when a teen talks about memories during general anesthesia that they might actually just be describing dreams during anesthesia?

People of all ages have described dreams during anesthesia. Most studies about dreams during anesthesia suggest that the dreams are usually not about things that are happening during the surgery and are usually not unpleasant or that different from dreams during non-anesthetic sleep. If the memories are upsetting, they should not be dismissed.

Will my parents/guardians be able to read my survey responses?

Once the Anesthesia Awareness Registry receives your survey in paper form or from ONLINE, only the members of the study team will have access to your survey. You parents would only be able to see your survey responses if you show them your paper form or the ONLINE survey before you hit send.

Brain Function Monitors

What is brain function monitoring?

Brain function monitors measures the very small waves of activity produced by the brain. They are designed to give an additional method of assessing when a patient is unconscious from anesthesia. Brain function monitors have also been called depth of anesthesia monitors. They are only one among the many monitors, such as heart rate, blood pressure, and anesthetic gas monitors that anesthesiologists use to assess the depth of anesthesia.

How do brain function monitors work?

When a person is asleep or anesthetized, brain wave activity is different than when a person is awake.  The monitor is attached to the patient’s forehead by taping a strip. This strip detects the brain wave activity which is displayed on a monitor screen. Then the anesthesiologist uses it along with other monitors during surgery to assist in assessing the depth of anesthesia.

Do brain function monitors reduce anesthesia awareness?

Awareness is difficult to study because it is a rare event. One study (Myles et al., 2004) found that use of a brain function monitor in patients who were at high risk for awareness reduced the number of patients with anesthesia awareness. The people who are at high risk include people with medical conditions or types of surgeries in which only lower doses of anesthesia may be safely given. However, there have not been any studies in people who are at low risk for anesthesia awareness. The American Society of Anesthesiologists (ASA) recommended that the decision of whether or not to use a brain function monitor should be made by the anesthesiologist individually for each patient.

Can I request that a brain function monitor be used for my anesthetic?

The brain function monitors are used in many, but not all operating rooms.  You should talk about any of your concerns regarding anesthesia, including awareness and brain function monitors with your anesthesiologist.