Table 3: Summary of Findings From Studies on Awareness and Recall (cont).

Study (year) and location	Recart et al. (2003) United States (27)	Puri and Murphy (2003) India (28)	Schneider et al. (2003) Germany (29)
Type of study	RCT Group 1: BIS Group 2: AEP Group 3: SP	RCT Group 1: BIS Group 2: SP	RCT Patients were randomized into 4 groups according to 4 different anesthetic techniques.
Quality of evidence	2	2	4-c
Primary purpose	To evaluate the impact of intraoperative monitoring with the BIS monitors or AEP on the use of desflurane, recovery time, and patient satisfaction	To investigate the impact of BIS monitoring on the hemodynamic stability and recovery time	To measure the ability of BIS monitoring to differentiate consciousness from unconsciousness during induction and emergence from anesthesia To measure the incidence of recall in surgical patients
Number of patients and type of surgery	90 healthy patients undergoing laparoscopic general surgery	30 adult patients undergoing valve replacement or coronary artery bypass grafting	40 adult patients undergoing elective surgery
Mean age, years (SD)	BIS: 47 (17) AEP: 42 (14) SP: 46 (15)	BIS: 38.25 (14.02) SP: 32.08 (13.84)	Group 1: 35 (range, 22–54) Group 2: 53 (range, 22–72) Group 3: 44 (range, 28–66) Group 4: 51 (range, 21–79)
Female/male	BIS: 21/9 SP: 20/10	Not reported	Group 1: 2/8 Group 2: 6/4 Group 3: 2/8 Group 4: 6/4
Premedication	Midazolam	Midazolam & morphine	None
Anesthetic agent	Propofol, fentanyl, and desflurane	Morphine, midazolam, thiopental, isoflurane, and nitrous oxide	Groups 1 & 2: Sevoflurane and remifentanil (different doses) Groups 3 & 4: Propofol and remifentanil (different doses)
Tracheal intubation	Yes	Yes	Yes
Muscle relaxant	Yes	Yes	No
Methods	In the SP group, the anesthesiologists were not permitted to observe BIS or AEP index values during the intraoperative period.	In the BIS group, the anesthesiologist adjusted the isoflurane concentration using BIS. In the control group, the anesthesiologist was blinded to the BIS scores. Patients were interviewed on the first day after their operations to determine any recall. Planned BIS scores: During the surgery: 45–55 Last 30 minutes: 65–75	Every 30 seconds after the induction of anesthesia, investigators twice asked the patients to squeeze the investigators’ hands. • At the induction stage, anesthetics were given until loss of consciousness (LOC1) • After tracheal intubation, the anesthetics were stopped until return of consciousness (ROC1) • For surgery, anesthetics were restarted until LOC2 • After surgery, anesthetics were discontinued (ROC2) Patients were interviewed in the recovery room, within 48 hours after surgery, and 2–3 weeks after surgery.
Intraoperative measurements	AEP, HR, BP, ECG, pulse oximetry, and capnography	HR, ECG, BP, and pulse oximetry	PSI, SEF, MF, HR, MAP, O2saturation, and CO2
Mean BIS values (SD)	BIS group: 49 (13) SP group: 40 (11)	BIS group: 75 (5.59) SP group: 67.42 (15.24)	LOC1 & LOC2: 66 (17) ROC1 & ROC2: 79 (14) LOC1: 62 (19) LOC2: 70 (16) ROC1: 78 5) ROC2: 81 4) Range of BIS values (these are approximate; the numbers were derived from the graph): LOC1: 25100 LOC2: 3395 ROC 1: 45100 ROC2: 53100 Between anesthetic groups: BIS values in patients receiving sevoflurane with dose remifentanil were significantly different from those in patients with propofol/remifentanil (groups 3 & 4 [P <.01])
Incidence of recall	At the time of discharge from the PACU, and at the 24-hour follow-up evaluation, none of the patients reported recall of any intraoperative events.	BIS: 0 SP: 1	No patient remembered being aware.
Accuracy data/prediction probability	N/A	N/A	For detection of consciousness and BIS threshold of 60: Sensitivity: 90.6% Specificity: 26.3% PPV: 55.1% NPV: 73.7% Prediction probability (Pk) For detection of consciousness in the 4 groups (mean [SEM]): Group 1: 0.684 (0.61) Group 2: 0.668 (0.061) Group 3: 0.743 (0.056) Group 4: 0.721 (0.057)* *Significantly different from group 1, P <.01