Recall of surgery for major trauma.

Major traumatic injury frequently causes hemodynamic instability that necessitates reducing the usual dose of anesthetic given for surgery. Nevertheless, a lower dose may be sufficient to provide anesthesia because of conditions present in trauma victims that are known to reduce anesthetic requirement (hypotension, hypothermia, and acute alcohol intoxication). To determine the incidence and patient perception of recall of surgery, 51 patients were interviewed after surgery for major trauma. Patients were assigned to one of two groups. Thirty-seven patients were given an anesthetic for endotracheal intubation and had continuous or almost continuous anesthesia during surgery. Of the four who recalled surgery (11%), two considered this awareness their worst hospital experience. Fourteen other patients, who were more severely injured, were not given an anesthetic for endotracheal intubation and/or for 20 or more consecutive minutes during surgery. Of the six patients in this group who recalled surgery (43%), two considered this awareness their worst hospital experience. No condition known to reduce anesthetic requirement did so reliably enough that recall of surgery did not occur when the anesthetic dose had to be reduced because of major trauma. The authors conclude that the incidence of recall of surgery in victims of major trauma is considerable, and that reducing the dose of anesthetic increases this incidence, despite the presence of conditions known to reduce anesthetic requirement.