Optimization of desflurane administration in morbidly obese patients: a comparison with sevoflurane using an ‘inhalation bolus’ technique

Abstract

Immediate recovery was significantly faster in the desflurane group. Overall hypnotic controllability measured by BIS was less accurate with desflurane. Overall haemodynamic controllability was better when using desflurane. Fewer episodes of hypotension were found in the desflurane group. The use of the inhalation bolus was found to be appropriate in both groups without causing severe haemodynamic side effects. Minimal BIS values were significantly lower after a desflurane bolus.

Postoperative recovery after anesthesia in morbidly obese patients: a systematic review and meta-analysis of randomized controlled trials

“…Among these studies, De Baerdemaeker et al evaluated 50 obese patients and reported distinct outcome measurements in two studies. 3,15 In all trials, the recruited patients were American Society of Anesthesiologists (ASA) status I-III who underwent general anesthesia with endotracheal intubation. In addition, in all trials except one, the patients underwent elective bariatric operations; the one exception included obese patients who underwent intraabdominal, orthopedic, or other surgery.…”

“…In seven trials, desflurane was compared with sevoflurane for maintenance of anesthesia. 3,[13][14][15][16][17][18] Two studies compared the recovery profiles of patients given sevoflurane vs isoflurane for maintenance of anesthesia. 19,20 Another two studies compared the recovery parameters of patients given intravenous anesthesia with those given propofol and inhalational anesthesia.…”

“…Three studies used acceptable methods of randomization, 17,18,20 and four studies clearly described the method of allocation concealment. 3,13,20,21 Three studies did not mention the blinding procedure, 15,19,22 and only one reported no blinding of the outcome assessors. 18 Eight studies incorporated an intention-to-treat analysis, 3,13,15,16,[18][19][20]22 and in all trials, an acceptable number of patients (\ 20%) withdrew during the follow-up periods .…”

Brief review: Theory and practice of minimal fresh gas flow anesthesia

“…At 1 LÁmin -1 , the average time to control the MAP was significantly shorter with desflurane [17 (12) min] than with isoflurane [29 (16) min], with 60% of the patients in the isoflurane group requiring rescue therapy. De Baerdemaeker et al 55 studied fifty morbidly obese patients undergoing laparoscopic gastroplasty who received BIS-guided sevoflurane or desflurane anesthesia in combination with a remifentanil target-controlled infusion. Intraoperative hemodynamic stability and BIS control were measured.…”

“…Returning the fresh gas to minimal flow but keeping the vaporizer setting about 25% greater than the previous setting is a bolus technique shown to improve stability and avoid overcorrection. 55 Likewise, reducing the anesthetic depth requires a major change in the vaporizer setting. A full closure of the vaporizer alone will lead to a slow decrease in Etaa; a bolus of fresh gas under observation of the Fiaa and Etaa is recommended if a more rapid reduction in anesthetic depth is required.…”