General anesthesia for morbidly obese patients--an examination of postoperative outcomes

Specific postoperative outcomes were assessed in 67 morbidly obese subjects who received general anesthesia for gastric stapling. Each patient was randomly assigned to receive N2O:O2 combined with fentanyl (n = 20), enflurane (n = 24), or halothane (n = 23). Time from last skin stitch until the patient opened eyes on command was significantly less for the fentanyl group (3.0 +/- 0.7 min) than for the enflurane group (13.2 +/- 1.9 min) or the halothane group (17.4 +/- 2.9 min) with P less than 0.05. However, no significant differences in time from last skin stitch to extubation were noted among the fentanyl (16.2 +/- 7.4 min), enflurane (15.2 +/- 1.6 min), and halothane (21.6 +/- 5.8 min) groups (P greater than 0.05). Recovery room (RR) admission temperatures were similar for the three groups: fentanyl, 36.1 +/- 0.1 degrees C; enflurane, 35.7 +/- 0.2 degrees C; and halothane, 36.0 +/- 0.1 degrees C (P greater than 0.05). Total RR time was not significantly different: fentanyl, 108 +/- 6 min, enflurane, 118 +/- 4 min; and halothane, 112 +/- 10 min (P greater than 0.05). In addition, no difference in RR and 24-hour postoperative narcotic (meperidine) requirements was demonstrated among the anesthetic groups. These data suggest that increased lipid solubility of volatile anesthetics (halothane or enflurane) produces neither delayed awakening nor prolonged recovery time in morbidly obese subjects. Considering the early (24 hour) postoperative outcomes studied, there is little to commend one general anesthetic technique over another in the obese subset of the population.