Loren Levy

Desflurane Versus Propofol Anesthesia: A Comparative Analysis in Outpatients

This study compares the induction, hemodynamic, and recovery characteristics of a general anesthetic with desflurane to one with propofol. Sixty outpatients presenting for orthopedic surgery received either a propofol induction of anesthesia followed by desflurane and nitrous oxide (Group 1), a propofol induction followed by propofol infusion and nitrous oxide (Group 2), a desflurane and nitrous oxide induction and maintenance (Group 3), or a desflurane induction and maintenance (Group 4). The quality of induction was inferior in Groups 3 and 4 with more breath-holding and excitation than in Groups 1 and 2. However, there was a more rapid emergence in Group 4 patients than any of the other groups. Group 4 patients were able to say their names (5.6 +/- 2.0 min vs 10.3 +/- 3.3 min, 8.6 +/- 3.1 min, and 9.3 +/- 1.5 min for Groups 1, 2, and 3, respectively) sooner after the discontinuation of anesthesia. Nonetheless, intermediate recovery was similar in Groups 2 and 4 being numerically but not statistically more rapid than in Groups 1 and 3. This pattern of intermediate recovery was also demonstrated by psychomotor function test results. Although there was no difference between the groups in postoperative narcotic requirement, more patients in Group 3 vomited (50%) than in either Group 2 (0%) or Group 4 (12.5%). Hemodynamically, the anesthetics were very similar. Although desflurane was a difficult drug to use for induction of anesthesia, this study demonstrates that desflurane is a suitable maintenance anesthetic for ambulatory surgery because it provides a rapid awakening and an intermediate recovery similar to propofol.

Dose-response study of droperidol and metoclopramide as antiemetics for outpatient anesthesia

During the past decade the demand for outpatient surgery has grown rapidly. To keep pace with the changing surgical environment, anesthesiologists have been modifying their anesthetic techniques to ensure a more rapid and a smoother recovery. However, postoperative nausea and vomiting remain the most common anesthesia-related side effects in outpatient surgical facilities (1,2). The incidence of postoperative nausea and vomiting in female outpatients undergoing laparoscopy has been reported to be as high as 50-60% (3). The incidences after strabismus surgery (4) and after therapeutic abortions (5) are also high. A prophylactic antiemetic would be of great value in outpatient surgery and anesthesia. A large number of papers have been published suggesting the use of droperidol, a butyrophenone derivative, as a prophylactic antiemetic agent. Although the majority of the authors found droperidol to be an effective antiemetic, the recommended doses vary widely (4,643). However, side effects, especially somnolence, have been reported with larger doses (4,9). Metoclopramide, a dopaminergic receptor blocker devoid of sedative effects, has also been advocated as an antiemetic, but conflicting results have been reported regarding its efficacy (5,lO-14). A recent paper by Rao, et al. (15) reported no nausea or

Upper respiratory tract infections and general anaesthesia in children : Peri-operative complications and oxygen saturation

Conflicting reports regarding the hazards of anaesthesia in children presenting for surgery with an upper respiratory tract infection have appeared in the literature. In the present study 130 children undergoing general anaesthesia with face mask for myringotomy and grommet insertion were graded as having either an acute or recent upper respiratory tract infection or were asymptomatic according to predetermined clinical symptoms and signs. The severity of respiratory and related complications were scored during induction, emergence and recovery. The peripheral oxygen saturation was recorded during induction, emergence, transfer to the recovery ward and in the recovery ward itself. There were no significant differences (p > 0.05) in the complication scores between the three groups of children. However, the incidence of hypoxaemia (oxygen saturation ± 93%) was significantly greater during transfer in the acute infection group (p = 0.001) and the recent infection group (p = 0.02), as well as during recovery in the acute group (p = 0.03) compared with asymptomatic children.

Intraoperative ketorolac has an opioid-sparing effect in women after diagnostic laparoscopy but not after laparoscopic tubal ligation.

Ketorolac tromethamine (Toradol Registered Trademark) is a parenteral, nonsteroidal antiinflammatory drug that is being extensively used to provide postoperative analgesia.This study evaluated whether intraoperative ketorolac would act synergistically with fentanyl to decrease postoperative analgesic requirements in outpatients undergoing gynecologic procedures. The patients studied were adult ASA physical status I or II females scheduled for diagnostic laparoscopy (DL) (n = 80) or laparoscopic tubal ligation (TL) (n = 46). Each patient received fentanyl 2 micro gram/kg intravenously (IV) before induction, followed by a standardized propofol anesthetic and 2 mL of saline or ketorolac 60 mg IV in a randomized double-blind fashion 30 min before the anticipated end of the operative procedure. Patients were assessed for postoperative pain via a 10-cm visual analog scale (VAS) (0 = no pain; 10 = severe pain) before analgesic treatment in the postanesthesia care unit (PACU). Severe postoperative pain (VAS of 5 or more) was treated with incremental doses of fentanyl, 25-50 micro gram IV by a blinded PACU nurse. Ibuprofen or acetaminophen with codeine was administered for pain control once the patient tolerated oral medications. This study showed that intraoperative ketorolac (60 mg IV) with fentanyl (2 micro gram/kg IV) administered at the induction of anesthesia resulted in significant opioid sparing and a diminution in pain in the DL sample but not in the TL sample. The analgesic regimen was also associated with a lower incidence of nausea and vomiting and resulted in earlier discharge, which was not seen after TL. These results demonstrate that pain after TL is far greater than that after DL, which suggests that these procedures should be considered separately when designing analgesic regimens. (Anesth Analg 1996;82:732-7)

Propofol versus thiamylal-enflurane anesthesia for outpatient laparoscopy.

STUDY OBJECTIVE To determine whether propofol anesthesia differs from thiamylal-enflurane anesthesia in induction characteristics, intraoperative hemodynamics, postoperative side effects, and postoperative psychomotor function recovery. DESIGN A randomized, double-blind, two-group study. SETTING A large university hospital with gynecologic outpatient operations performed in an integrated operating room suite. PATIENTS Sixty adult women (ASA physical status I or II) undergoing an outpatient gynecologic laparoscopic operation with an anesthesia time of approximately 60 minutes. INTERVENTIONS No pharmacologic premedication. Pretreatment with intravenous droperidol 0.6 mg and sufentanil 0.2 micrograms/kg before induction of anesthesia. Anesthesia was induced with either thiamylal 4 mg/kg (Group 1) or propofol 2.5 mg/kg (Group 2). Anesthesia was maintained with either nitrous oxide (N2O) and enflurane, 2-0.5% inspired concentrations; (Group 1) or with a continuous infusion of propofol 200-100 micrograms/kg/min and N2O (Group 2). MEASUREMENTS AND MAIN RESULTS In psychomotor function tests (Trieger dot test and p-deletion test) administered preoperatively and postoperatively, no difference was found between the groups. No difference was found in induction time, although significantly more patients reported pain after the propofol injection, or in intraoperative hemodynamics (mean arterial pressure and heart rate). Immediate recovery time (emergence from anesthesia) and intermediate recovery time (ambulation, oral intake, and discharge time) were significantly shorter after propofol anesthesia. Fewer postoperative side effects, such as nausea and vomiting, were reported after propofol anesthesia. CONCLUSIONS Induction and maintenance of anesthesia with propofol were comparable to those with thiamylal-enflurane, except patients experienced more pain on injection after propofol. Both immediate and intermediate recovery were more rapid after propofol anesthesia compared with enflurane-based anesthesia.

Recovery characteristics of three anaesthetic techniques for outpatient orthopaedic surgery

The goals of this study are to observe prospectively the perioperative recovery characteristics associated with general anaesthesia (GA), spinal anaesthesia (SAB), and epidural anaesthesia (EPID) in 200 patients scheduled for outpatient knee arthroscopy. Patients were observed from the time they entered the recovery room until they were discharged. Patients were contacted on postoperative days (POD) 1, 3, and 5. The EPID group had the quickest recovery times (125 f 37 min, mean f SD, ANOVA P < 0.01) compared with the GA group (165 f 57 min) and SAB group (167 51 min). Comparing the side effects of the three anaesthetic techniques, GA was associated with the highest incidence of nausea (27%) and vomiting (16%) on the day of surgery that persisted into the first postoperative day (nausea 41% and vomiting 22%). There was no difference in the incidence of headache overall; however, SAB was associated with a 13% incidence of postdural puncture (PDP) headache that became apparent on POD 3. All the PDP headaches resolved with conservative therapy by the first postoperative week, except for two patients who required an epidural blood patch. The EPID group followed by the SAB and GA groups, had the highest incidence of backaches on POD 1 (respectively, 63%, 41% and 17%). By POD 3, the incidence of backache was not statistically different between groups. No specific treatment for backache was required. The ideal anaesthetic has not been developed, but our data suggests that an epidural technique is advantageous for knee arthroscopy in terms of a quick recovery and minimal adverse effects.