Q&A: Anesthesia Awareness During Surgery




Why does awareness during surgery happen and why are some patients at risk?

Anesthesiologists are committed first and foremost to protecting the life of the patient and making the patient as comfortable as possible. In some high-risk surgeries, such as trauma, cardiac surgery, emergency cesarean delivery, or in situations involving a patient whose condition is unstable, using the usual dose of anesthetic drugs could harm the patient. In these and other critical or emergency situations, there can be a greater risk of awareness during surgery because the patient cannot be put safely into a deeper anesthetic state.

In addition, some patients may react differently to the same level or type of anesthesia. Different medications can mask important signs that anesthesia professionals monitor to help determine the depth of anesthesia. In other rare instances, technical failure or human error may contribute to unexpected episodes of awareness.

What should the patient do before surgery to minimize the risk of intraoperative awareness?

There are several steps the patient should take before surgery to ensure the safest and most comfortable outcome:

  • Meet with your anesthesiologist before surgery to discuss all anesthesia options.
  • Tell your anesthesiologist about any problems with previous anesthetics, including any history of intraoperative awareness.
  • Discuss all medications you are taking, both prescription and over-the-counter. This information is vital to creating an anesthetic plan specifically for your needs.
  • If you are concerned about awareness during surgery, tell your anesthesiologist and ask questions about what precautions are taken to avoid it. Don’t be afraid to voice your concerns.

What will the anesthesiologist do during surgery to keep the patient safely under general anesthesia?

During surgery, your anesthesiologist will carefully monitor your vital signs, such as your heart rate, breathing rate, and blood pressure to help gauge the depth of anesthesia. In addition, sophisticated technology is available to gauge the presence of anesthetic in the administered gas mixture. Your anesthesiologist may also use brain function monitors intended to measure the depth of anesthesia. The impact of these technologies on the risk of awareness is unclear, so the decision to use them is often made on a case-by-case basis by the anesthesiologist.

No monitor can completely guarantee a patient will not experience awareness during surgery. But you should feel confident relying on your anesthesiologist to guide you safely through your surgery by relying on his or her clinical experience, training and judgment combined with appropriate technology.

What should I do if I think I have experienced intraoperative awareness?

If you believe you experienced an episode of awareness during surgery, tell your anesthesiologist or another health care professional as soon as you are able. Your anesthesiologist will tell you the events in the operating room and whether any of them would have contributed to awareness. If necessary, you will be referred to a counselor right away to help deal with the feelings associated with awareness. It is important to note that a variety of anesthetic agents are often used, some of which may create false memories or no memory at all of the various events surrounding surgery.

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The ASA does not employ physician anesthesiologists on staff and cannot respond to patient inquiries regarding specific medical conditions or anesthesia administration. Please direct any questions related to anesthetics, procedures or treatment outcomes to the patient’s anesthesiologist or general physician.