Propofol-nitrous Oxide Research Articles

Efficacy of Esmolol Versus Alfentanil as a Supplement to Propofol-Nitrous Oxide Anesthesia

In 97 outpatients undergoing ambulatory arthroscopic procedures, we compared esmolol with alfentanil when used to supplement propofol-N2O-atracurium anesthesia according to a randomized, double-blind protocol. After an initial intravenous dose of 16 micrograms/kg alfentanil, or 2 mg/kg of esmolol, a variable-rate infusion of alfentanil or esmolol was administered to maintain a stable heart rate. After induction of anesthesia with 2.5 mg/kg of propofol, mean arterial pressure decreased to a larger extent in the alfentanil-treated patients. Although heart rate and mean arterial pressure increased in both groups after tracheal intubation, alfentanil more effectively blunted the hemodynamic response to this stimulus. Maintenance of anesthesia was adequate in both treatment groups. After discontinuation of anesthesia, patients in the esmolol group opened their eyes earlier (7.2 +/- 2.4 min vs 9.8 +/- 4.6 min) than those in the alfentanil group. Esmolol-treated patients also reported less sedation in the first 15 min of recovery than those receiving alfentanil. However, there were no differences in times to ambulation and discharge between the groups. Esmolol-treated patients reported more postoperative pain for the first 15 min of recovery and more esmolol-treated patients required postoperative opioid analgesia than those treated with alfentanil. There were no significant differences in the incidences of nausea and vomiting between the two groups. The authors conclude that esmolol may be used in place of alfentanil to supplement propofol-N2O-atracurium anesthesia in outpatients undergoing arthroscopic procedures. However, hemodynamic responses to tracheal intubation were larger with esmolol, and avoidance of alfentanil did not decrease the incidence of postoperative nausea and vomiting in this outpatient population.

The differential cost of anesthesia and recovery with propofol-nitrous oxide anesthesia versus thiopental sodium-isoflurane-nitrous oxide Anesthesia

Study Objective: To assess the recovery room profile of Propofol in outpatient anesthesia and to compare it to the profile of a standard technique. Design: A comparative, randomized, double-blind, third-party open .study. Setting: Ambulatory Surgery Center at The Emory Clinic. Patients: Ninety-nine ASA physical status I, II, or III nonpregnant female patients who had been diagnosed as needing breast biopsies. Interventions: All patients were given 1 μg/kg of fentanyl prior to induction. Those in the Propofol group were induced with 2.0 to 2.5 mg/kg of propofol and maintained with a 100 to 200 μg/kg/min infusion of Propofol with nitrous oxide (N 2O) in oxygen (0 2). In the thiopental sodium-isofurane group, patients were induced with 4.0 to 5.0 mg/kg of thiopental sodium and maintained with isoflurane and N 20 in 0 2. Measurements and Main Results: Recovery from anesthesia was assessed by an evaluator who was unaware of the anesthetic technique used for each patient. Immediate recovery time was measured in terms of awakening, response to verbal command, and orientation to time and place. A brief postoperative follow-up questionnaire was completed to assess the patients' subjective feelings regarding their ability to eat, concentrate, and resume normal activities. In the thiopental sodium-isofurane group, 15 of 50 patients (30%) had nausea and vomiting, but in the propofol group, only 4 of 49 patients (8.1%) had nausea and vomiting ( p < 0.01). The latter group resumed normal activity (i.e., reading and watching television) 7.93 ± 0.76 hours postanesthesia, whereas the thiopental sodium-isoflurane group resumed normal activity 17.02 ± 1.21 hours postanesthesia ( p < 0.001). Patients in the propofol group returned to work in an average of 1.5 ± 0.09 days, compared with 2.0 ± 0.09 days for the thiopental sodium-isoflurane group ( p < 0.001). Conclusions: The propofol group needed less nursing care and returned to more productive activity earlier than did the thiopental sodium-isoflurane group.

Use of Desflurane for Outpatient Anesthesia A Comparison with Propofol and Nitrous Oxide

Desflurane's induction and recovery characteristics were compared to those of propofol-nitrous oxide in outpatients undergoing laparoscopic procedures. Ninety-two healthy patients were randomized to receive either: 1) propofol induction and propofol-nitrous oxide maintenance (control), 2) propofol induction and desflurane-nitrous oxide maintenance, 3) desflurane-nitrous oxide, or 4) desflurane alone for induction and maintenance of anesthesia. Inhalation induction with desflurane-nitrous oxide was faster than with desflurane alone (100 +/- 35 vs. 124 +/- 43 s). Inhalation inductions were associated with a high incidence of apnea (17 and 26%), breath-holding (26 and 39%), and coughing (30 and 22%) in groups 3 and 4, respectively. The emergence time after discontinuation of desflurane in oxygen (4.5 +/- 2.1 min.) was significantly less than that after propofol-nitrous oxide (7.3 +/- 3.9 min.). However, times from arrival in the recovery room until the patients were judged fit for discharge were similar for all four treatment groups. Digit-symbol substitution test results and sedation visual analogue scores also were similar during the first 2 h in the recovery room. A lower incidence of moderate-to-severe nausea was reported in group 1 (15% vs. 52, 52, and 59% in groups 2, 3, and 4, respectively). In conclusion, induction of anesthesia with desflurane was rapid but is associated with a high incidence of airway irritation. Emergence and recovery profiles after maintenance of anesthesia with desflurane compared favorably to a propofol-nitrous oxide combination. However, propofol was associated with a lower incidence of nausea than was desflurane after outpatient anesthesia for laparoscopic surgery.

Randomized Comparison of Outcome After Propofol-Nitrous Oxide or Enflurane-Nitrous Oxide Anesthesia in Operations of Long Duration

Randomized Comparison of Outcome After Propofol-Nitrous Oxide or Enflurane-Nitrous Oxide Anesthesia in Operations of Long Duration