In this systematic review we focused on postoperative recovery and complications using four different anesthetic techniques. The database MEDLINE was searched via PubMed (1966 to June 2002) using the search words "anesthesia" and with ambulatory surgical procedures limited to randomized controlled trials in adults (>19 yr), in the English language, and in humans. A second search strategy was used combining two of the words "propofol," "isoflurane," "sevoflurane," or "desflurane ". Screening and data extraction produced 58 articles that were included in the final meta-analysis. No differences were found between propofol and isoflurane in early recovery. However, early recovery was faster with desflurane compared with propofol and isoflurane and with sevoflurane compared with isoflurane. A minor difference was found in home readiness between sevoflurane and isoflurane (5 min) but not among the other anesthetics. Nausea, vomiting, headache, and postdischarge nausea and vomiting incidence were in favor of propofol compared with isoflurane (P < 0.05). A larger number of patients in the inhaled anesthesia, groups required antiemetics compared with the propofol group. We conclude that the differences in early recovery times among the different anesthetics were small and in favor of the inhaled anesthetics. The incidence of side effects, specifically postoperative nausea and vomiting, was less frequent with propofol.

Study Objective: To determine if remifentanil would offer a superior hemodynamic and recovery Profile compared to the current standard of care, which implements a fentanyl-based technique.Design: Randomized, single-blind study.Setting: Outpatient center associated with tertinuy rare centerPatients: 75 outpatients undergoing microsuspension laryngoscopy.Interventions: Patients were randomized to either a remifentanil induction (0.5 mug/kg/min) and maintenance (0.25 mug/kg/min) versus fentanyl (maximum of 250 muh) as the only opioid. All patients received propofol as part of the induction and maintenance with or without the use of nitrous oxide.Measurements: Assessment of hemodynamics [heart rate (HR) and blood pressure(BP)], presence of perioperative myocardial ischemia on ambulatory electrocardiographic monitoring, and time to discharge.Main Results: Significantly fewer patients in the remifentanil group demonstrated episodes of tachycardia (HR > 100 beats per min) compared to the fentanyl group (14 % vs. 40 %, p < 0.05), with significantly fewer episodes of tachycardia and hypertension per patient. Recovery profiles between the two groups did not show clinically significant differences.Conclusions: Remifentanil, a new short-acting opioid, offers excellent hemodynamic control for brief intense outpatient procedures Performed in high-risk patients; however, its use was not associated with any improvement in recovery profiles. (C) 2000 by Elsevier Science Inc.

This study was designed to determine and compare the dose-response characteristics, speed of onset, and relative potency of single-dose epidural fentanyl (F) and sufentanil (S) for postoperative pain relief. Eighty women undergoing cesarean section (C/S) with epidural 2% lidocaine with epinephrine (1:200,000) were randomly assigned to receive double-blind epidural administration of F (25, 50, 100, or 200 micro g) or S (5, 10, 20, or 30 micro g) (n = 10 per group) upon complaint of pain postoperatively. Visual analog scales (VAS, 0-100 mm) were used to assess pain and sedation at baseline; at 3, 6, 9, 12, 15, 20, 25, 30, 45, and 60 min; and every 30 min until further analgesia was requested. The study was terminated at 30 min if satisfactory analgesia was not achieved. Side effects were recorded. A dose-response was demonstrated for both opioids. F 25 micro g and S 5 micro g were ineffective, with significantly fewer women achieving VAS scores <10 mm (P < 0.05 compared with F 100 or 200 micro g and S 20 or 30 micro g). F 100 and 200 micro g and S 20 and 30 micro g all achieved VAS scores <10 mm in all women with no differences in time to 50% reduction in VAS (mean 11-16 min) and no differences in duration of analgesia (mean 117-138 min). The 50% and 95% effective dose values for each opioid to achieve a VAS score <10 mm were F 33 micro g and 92 micro g and S 6.7 micro g and 17.5 micro g. There were no differences among groups in sedation scores or side effects. Our data suggest that the relative analgesic potency of epidural S:F is approximately 5 and that there are no differences between the opioids in the onset, duration, and effectiveness of analgesia when equianalgesic doses are administered postoperatively after lidocaine anesthesia for C/S. (Anesth Analg 1997;85:365-71)

Background and Objectives. The authors studied the efficacy of sufentanil patient-controlled epidural analgesia (PCEA) for postoperative analgesia after cesarean delivery and compared these results to a morphine intravenous-patient-controlled-analgesia (IV-PCA) regimen. Methods. Fifty patients were randomized into two groups to receive sufentanil PCEA or morphine IV-PCA after cesarean delivery under epidural anesthesia. Visual-analog-scale pain scores (0-100 mm: 0 mm = no pain, 100 mm = worst pain), sedation, side effects, recovery times, and patient satisfaction were assessed through 4 p.m. on postoperative day (POD) 2. Results. Analgesia was similar in the two groups, except following the initial physician-administered loading dose when pain was rated significantly lower by patients in the PCEA group at 30 minutes (6 +/-2 mm versus 38 +/- 6 nun; P < .01) and at 2 hours (7 +/- 2 mm versus 27 +/- 5 mm; P < .05). Sedation was rated lower by patients in the PCEA group at 2 hours (P < .05). The incidence of nausea and vomiting was similar in both groups. The incidence of pruritus requiring treatment was greater in the PCEA group (57% versus 12%; P < .01). Length of hospitalization was not different. Patients were equally satisfied in both groups. Conclusions. Although sufentanil PCEA provided satisfactory sustained postoperative analgesia, sufentanil PCEA appears to offer no clear advantage over morphine IV-PCA beyond the effects of the initial physician-administered loading dose.

Some of the topics which have generated particular interest in obstetric anesthesia recently include the effects of epidural anesthesia on the progress of labor, the efficacy of volume preloading prior to spinal anesthesia for cesarean section, and the use of intraspinal opioids and of alpha-2 adrenergic agonists for labor analgesia.

The combination of catecholamines and halothane has long been recognized as arrhythmogenic. The purpose of this study was to evaluate whether the mechanism of this interaction originates at the single cell level. The incidence of spontaneous contractile waves occurring between stimulated beats (interbeat waves), early aftercontractions, and late aftercontractions was measured in rat myocytes exposed to sympathomimetics with and without halothane. Each of these endpoints in single cells has the potential to produce arrhythmias in multicellular preparations. Interbeat waves and late aftercontractions were observed with isoproterenol (1 X 10(-7) M) and norepinephrine (1-3 X 10(-7) M). The incidence of these phenomena was significantly reduced in the presence of 0.30 mM halothane. Early aftercontractions occurred in the presence of isoproterenol (1 X 10(-7) M), norepinephrine (1-3 X 10(-7) M), and phenylephrine (5-10 X 10(-6) M). There was a statistically significant decrease in the incidence of early aftercontractions in the presence of 0.30 mM halothane. These results indicate that the mechanism behind the clinically observed increased arrhythmogenicity of catecholamines with halothane does not arise at the level of single ventricular cells because halothane inhibited sympathomimetic-induced arrhythmogenic activity in this model. The probable mechanisms rather include altered impulse propagation, which might lead to phenomena such as reentry.