Fewer Patients Awake During Operations
Rob Hicks, MD
March 14, 2013 -- Being aware of what's going on during an operation under general anesthesia sounds scary. The good news is a new study suggests it happens less often than had been thought.
Previous research has found that about 1 in 500 patients is aware or awake under general anaesthesia. The new report, from the U.K.'s Royal College of Anaesthetists, finds it is far less common, about 1 case in 15,000.
Researchers also found that even where brain monitoring equipment is available, fewer than 2% of anesthesiologists routinely use it to check the effectiveness of the anesthetic.
The findings come from the biggest study of its kind. It surveyed 7,125 anesthesiologists and coordinators at 329 hospitals across the U.K.
There were 153 cases of "accidental awareness" reported in 2011:
- 30% happened during surgery.
- 23% happened after surgery but before the full recovery time.
- 47% happened after anesthesia has begun but before surgery had started.
Awareness during surgery was more likely to lead to pain or distress.
"Waking up during surgery is a fear," says researcher Jaideep Pandit, DPhil, a consultant anaesthetist at Oxford University Hospitals in the U.K. "It's a legitimate fear."
He hopes the study will calm some concerns: "Anything to use data to be reassuring is always a good thing."
He admits some under-reporting is possible in the study. Anesthesiologists may have forgotten how many awareness cases they'd seen. Since anesthesiologists don't routinely see patients after operations, they may not always learn about the awareness report. Sometimes patients may forget the incident or think it is too trivial to mention.
From Terrified to Interested
How do patients describe the experience of being aware during an operation? These vary greatly, from "the very, very severe adverse experiences of a combination of pain, paralysis, terror," Pandit says, to anecdotal reports of patients almost being fascinated by what's happening around them: "Completely unconcerned and untroubled and almost interested in the proceedings."
He and colleagues are planning more research to focus on patient experiences. "Even for someone who reports they are not particularly bothered by it, at the very least it must be surprising for them."