Continuous spinal anesthesia/analgesia for perioperative management of morbidly obese patients undergoing laparotomy for gastroplastic surgery

Background: The authors determined prospectively the safety of continuous s pinal anesthesia combined with general anesthesia and the efficacy of posto perative pain relief with continuous spinal analgesia for morbidly obese pa tients undergoing vertical banded gastroplasty. Methods: 27 patients (13 men, 14 women) with a mean body mass index (BMI) o f 50.4 +/- 7.8 and several co-morbidities were studied. All patients were a nesthetized with the same anesthetic regimen, which included midazolam, fen tanyl, propofol, muscle relaxants, N2O, isoflurane and intrathecal bupivaca ine. Postoperative pain relief was provided for 5 days and all patients rec eived the same regimen, which included intrathecal buplvacaine, fentanyl an d intravenous tenoxicam. The intrathecal analgesic regimen was administered continuously through a pump which had the facility of providing bolus dose s when requested in predetermined lockout intervals. Intra-operative monito ring included hemodynamic and respiratory parameters. Additional postoperat ive monitoring included respiratory rate, degree of sedation, sensory level of anesthesia, motor response and intensity of pain. Results: Intraoperative anesthetic technique was safe and provided satisfac tory results in the immediate postoperative period. Furthermore, the postop erative analgesia regimen provided effective analgesia in all patients. The mean doses of fentanyl and bupivacaine infused intrathecally for the first 24 postoperative hours were 14.1 +/- 2.0 mu g.h(-1) and 0.7 +/- 0.1 mg.h(- 1) respectively, while the requirements of analgesia decreased progressivel y with time. The technique provided effective analgesia with low pain score s, which was reflected by ease in mobilizing and performing physical exerci ses with the physiotherapist. Only minor complications related to anesthesi a and analgesia were encountered. Conclusion: To our knowledge, this technique of anesthesia and postoperativ e analgesia has not been described before in morbidly obese patients. This regimen merits further controlled trials to establish its place in the peri operative management of morbidly obese patients.