Patients report a variety of experiences, ranging from vague, dreamlike states to being fully awake, immobilized, and in pain from the surgery.
However, intraoperative monitoring of anesthetic level with bispectral index (BIS) or end-tidal anesthetic concentration (ETAC) may help to reduce the incidence of intraoperative awareness, although clinical trials have yet to show a decreased incidence of AAGA with the BIS monitor.
Diagnosis is made postoperatively by asking patients about potential awareness episodes and can be aided by the modified Brice interview questionnaire.
A common but devastating complication of intraoperative awareness with recall is the development of post-traumatic stress disorder (PTSD) from the events experienced during surgery.
When paralyzed, patients may not be able to communicate their distress or alert the operating room staff of their consciousness until the paralytic wears off.
[11] One review showed that only about 35% of patients are able to report an awareness event immediately after the surgery, with the rest remembering the experience from weeks to months afterward.
[12] Depending on the awareness experience, patients may have postoperative psychological problems that range from mild anxiety to post-traumatic stress disorder (PTSD).
[7][13] PTSD is characterized by recurrent anxiety, irritability, flashbacks or nightmares, avoidance of triggers related to the trauma, and sleep disturbances.
The patient cannot signal distress and may not exhibit the signs of awareness that would be expected to be detectable by clinical vigilance, because other drugs used during anaesthesia may block or obtund these.
The anesthesia provider must weigh the need to keep the patient safe and stable with the goal of preventing awareness.
The American Society of Anesthesiologists in 2007 released a Practice Advisory outlining the steps that anesthesia professionals and hospitals should take to minimize these risks.
Current research attributes the incidence of AAGA to a combination of the risks mentioned above, together with ineffective practice from ODPs, anesthetic nurses, HCAs and anesthetists.
If nitrous oxide delivery suffers due to a leak in its regulator or tubing, an 'inadequate' mixture can be delivered to the patient, causing awareness.
This may also be caused by an empty vaporizer (or nitrous oxide cylinder) or a malfunctioning intravenous pump or disconnection of its delivery tubing.
The aim of conscious sedation or MAC is to provide a safe and comfortable anesthetic while maintaining the patient's ability to follow commands.
For instance, with a caesarean delivery, the goal is to provide comfort with neuraxial anesthetic yet maintain consciousness[19] so that the mother can participate in the birth of the child.
The decision to provide MAC versus general anesthesia can be complex, involving careful consideration of individual circumstances and discussion with the patient about their preferences.
New research has been carried out to test what people can remember after a general anesthetic, in an effort to understand anesthesia awareness more clearly and help to protect patients from experiencing it.
It was also found that some patients require a more detailed interview to jog their memories for intraoperative experiences but these are only untraumatic cases.
If awareness is reported, a case review is immediately performed to identify machine, medication, or operator error.
[citation needed] Patients who experience full awareness with explicit recall may have suffered an enormous trauma due to the extreme pain of surgery.
Some patients experience post-traumatic stress disorder (PTSD), leading to long-lasting after-effects such as nightmares, night terrors, flashbacks, insomnia, and in some cases even suicide.
[citation needed] A study from Sweden in 2002 attempted to follow up 18 patients for approximately 2 years after having been previously diagnosed with awareness under anesthesia.