COMPARISON OF ISOFLURANE AND SEVOFLURANE FOR SHORT-TERM ANESTHESIA IN MEERKATS (SURICATA SURICATTA)-ARE THERE BENEFITS THAT OUTWEIGH COSTS?

Meerkats ( Suricata suricatta ) are routinely anesthetized with isoflurane in zoo and field settings. Twenty healthy adult meerkats of mixed age and sex held in the Zoological Society of London's collection were anesthetized with 4% isoflurane by face mask for routine health examinations. The procedure was repeated 5 mo later in the same group of animals utilizing sevoflurane at 5% for induction, and again 3 mo later with sevoflurane at 6.5% for induction to approximate equipotency with isoflurane. The speed and quality of induction and recovery were compared between the two volatile anesthetic agents. There was no statistically significant difference in the speed of induction across any of the anesthetic regimes. There was a significant difference in recovery times between isoflurane and 6.5% sevoflurane (427 ± 218 and 253 ± 65 sec, respectively [mean ± SD]). Under the conditions of this study, sevoflurane at 6.5% induction dose resulted in better quality induction and recovery than sevoflurane at 5% induction or isoflurane. The mean heart and respiratory rates during anesthesia were higher using 5% sevoflurane for induction but there was no significant difference in either rate between isoflurane and sevoflurane used at a 6.5% induction dose. This study suggests that sevoflurane at a dose of 6.5% for induction and 4% for maintenance is a safe and effective anesthetic agent in healthy adult meerkats. Rapid return to normal behavior after anesthesia is important in all zoo species but particularly so in animals with a complex social and hierarchical structure such as meerkats. For this species, the advantage afforded by the speed of recovery with sevoflurane may offset the cost in certain circumstances.

Limiting the accessibility of cost-prohibitive drugs reduces overall anesthetic drug costs: a retrospective before and after analysis.

PURPOSE: Cost effectiveness is becoming increasingly important in today's healthcare environment. Remifentanil, dexmedetomidine, and desflurane are costly agents that often have suitable alternatives to their use. We sought to identify changes in cost and outcomes following interventions that limited the availability of these drugs. METHODS: We calculated anesthetic drug costs for all operating room procedures performed before and after the accessibility interventions. We retrospectively compared drug costs per case and the frequency of agent use before and after the interventions. In addition, we analyzed the incidence of adverse outcomes, including delayed out-of-room times, postoperative nausea and vomiting (PONV), unplanned intubations, use of naloxone, and reintubations. Wilcoxon-Mann-Whitney and Chi square analyses were used to quantify differences in cost, use, and outcomes between cohorts. RESULTS: Of the 27,233 cases we identified, 24,201 cases were analyzed. The mean anesthetic drug costs per case were significantly lower after the interventions vs before at ($21.44 vs $32.39, respectively), a cost savings of $10.95 (95% confidence interval, $9.86 to $12.04; P < 0.001). Additionally, a comparison of data after vs before the interventions revealed the following results: remifentanil use was significantly lower (3.5% vs 9.2% of cases; P < 0.001). Dexmedetomidine use did not differ significantly (0.4% vs 0.5% of cases; P = 0.07), and desflurane use was significantly lower (0.6% vs 20.2% of cases; P < 0.001). There was no significant relationship between the interventions and the frequency of delayed out-of-room times (15.5% vs 15.9%; P = 0.41), unplanned intubations (0.02% vs 0.03%; P = 0.60), and reintubations (0.01% vs 0.03%; P = 0.28). Postoperative nausea and vomiting decreased significantly after the interventions (22.8% vs 24.4%; P = 0.003), and naloxone use showed a significant increase (0.22% vs 0.11% of cases; P = 0.04). CONCLUSIONS: Reducing the accessibility of these cost-prohibitive agents resulted in significant anesthetic drug cost savings and decreased utilization of remifentanil and desflurane. The interventions had no significant effect on patient recovery time, incidence of unplanned intubations, or incidence of reintubation, but they were associated with a decrease in PONV and an increase in naloxone use.

Effect of transversus abdominis plane block on cost of laparoscopic cholecystectomy anesthesia.

BACKGROUND: Use of transversus abdominis plane (TAP) block for postoperative analgesia is continuously increasing. However, few studies have investigated intraoperative effects of TAP block. We aimed to study the effects of TAP block in terms of cost-effectiveness and consumption of inhalation agents. MATERIAL AND METHODS: Forty patients undergoing laparoscopic cholecystectomy were enrolled in this study. Patients were randomly divided into 2 groups: Group 1 (n=20) patients received TAP block and Group 2 (n=20) patients did not receive TAP block. Standard anesthesia induction was used in all patients. For the maintenance of anesthesia, fractional inspired oxygen (FIO2) of 50% in air with desflurane was used with a fresh gas flow of 4 L/min. All patients were monitored with electrocardiography and for peripheral oxygen saturation (SpO2), end-tidal carbon dioxide (ET), heart rate (HR), noninvasive mean blood pressure (MBP), and bispectral index (BIS). Bilateral TAP blocks were performed under ultrasound guidance to Group 1 patients. The BIS value was maintained at between 40 and 50 during the surgery. The Dion formula was used to calculate consumption of desflurane for each patient. RESULTS: There was no difference between the groups with respect to demographic characteristics of the patients. Duration of anesthesia, surgery time, and dosage of fentanyl were similar in the 2 groups. However, the cost and consumption of desflurane was significantly lower in Group 1. CONCLUSIONS: Total anesthesia consumption was lower and the cost-effectiveness of anesthesia was better in TAP block patients with general anesthesia than in non-TAP block patients undergoing laparoscopic cholecystectomy.

Calculation of volatile anaesthetics consumption from agent concentration and fresh gas flow.

BACKGROUND: The assessment of volatile agents' consumption can be performed by weighing vapourisers before and after use. This method is technically demanding and unavailable for retrospective analysis of anaesthesia records. Therefore, a method based on calculations from fresh gas flow and agent concentration is presented here. METHODS: The presented calculation method herein enables a precise estimation of volatile agent consumption when average fresh gas flows and volatile agent concentrations are known. A pre-condition for these calculations is the knowledge of the vapour amount deriving from 1 ml fluid volatile agent. The necessary formulas for these calculations and an example for a sevoflurane anaesthesia are presented. RESULTS: The amount of volatile agent vapour deriving from 1 ml of fluid agent are for halothane 229 ml, isoflurane 195 ml, sevoflurane 184 m, and desflurane 210 ml. The constant for sevoflurane is used in a fictitious clinical case to exemplify the calculation of its consumption in daily routine resulting in a total expenditure of 23.6 ml liquid agent. CONCLUSIONS: By application of the presented specific volatile agent constants and equations, it becomes easy to calculate volatile agent consumption if the fresh gas flows and the resulting inhaled concentration of the volatile agent are known. By this method, it is possible to extract data about volatile agent consumption both ways: (1) retrospectively from sufficiently detailed and accurate anaesthesia recordings, as well as (2) by application of this method in a prospective setting. Therefore, this method is a valuable contribution to perform pharmacoeconomical surveys.

Halothane: how should it be used in a developing country?

The anaesthetic agent halothane is still widely used in developing countries including the Islamic Republic of Iran because of its low price. Because of halothane-induced hepatitis, a rare complication, it has been replaced by other inhalation anaesthetics in Western countries; it has been suggested by some Iranian professionals that the Islamic Republic of Iran should do the same. We evaluated various dimensions of this replacement through a literature review to assess the incidence of halothane-induced hepatitis and costs of anaesthetics in the country. We also conducted a questionnaire survey of 30 anaesthesiology/gastroenterology experts about their views on the subject. The results indicate that the incidence of halothane hepatitis in the Islamic Republic of Iran is very low and could mostly be avoided by strict adherence to guidelines. Complete withdrawal of halothane in the Islamic Republic of Iran might not be appropriate at present. Comprehensive cost-effectiveness studies are needed before a decision is made on complete replacement of halothane with other anaesthetics.

Effects of lidocaine infiltration on cost of rhinoplasty made under general anesthesia.

This study aimed to compare the effects of combined and noncombined lidocaine with adrenaline infiltration in general anesthesia (GA) procedures, in which the standard anesthesia depth is monitored by Bispectral Index monitoring, on minimum alveolar concentration (MAC) levels and the costs. Following approval by the local ethics committee, an American Society of Anesthesiologists physical status I­II group of 40 adult patients for whom elective rhinoplasties under GA were planned was divided into 2 double-blind randomized groups. In group 1, GA and lidocaine + adrenaline were administered, whereas in group 2, only GA and adrenaline were administered. All the patients who had been taken to the operation room underwent electrocardiography and measurements of the peripheral oxygen saturation, end-tidal carbon dioxide, heart rate, mean blood pressure, and Bispectral Index monitoring. Using the operation time and the MAC% values, the total consumed inhalation agent amounts were calculated, and the cost difference was determined. The mean blood pressure values were lower in group 1 (P < 0.05). In group 1, the MAC% was 20.83% lower than that of group 2; the consumed desflurane amount was 20.29%, and the cost was 20.29% lower than that of group 2 (P < 0.05). In rhinoplasties under GA, the lidocaine + adrenaline combination infiltration not only decreased inhaled anesthetic requirement and cost but also supported the hemodynamic stability. In addition, surgical satisfaction increased in the lidocaine + adrenaline group because of small number of agitated patients during the recovery period.

Meta-analysis of average and variability of time to extubation comparing isoflurane with desflurane or isoflurane with sevoflurane.

BACKGROUND: We recently determined how to use anesthesia information management system data to model the time from end of surgery to extubation. We applied that knowledge for meta-analyses of trials comparing extubation times after maintenance with desflurane and sevoflurane. In this study, we repeated the meta-analyses to compare isoflurane with desflurane and sevoflurane. METHODS: A Medline search through December 2009 was used to identify studies with (1) humans randomly assigned to isoflurane or desflurane groups without other differences (e.g., induction drugs) between groups, and (2) mean and SD reported for extubation time and/or time to follow commands. The search was repeated for random assignment to isoflurane or sevoflurane groups. We considered extubation times >15 minutes (representing 15% of cases in the anesthesia information management system data) to be prolonged. RESULTS: Desflurane reduced the mean extubation time by 34% and reduced the variability in extubation time by 36% relative to isoflurane. These reductions would reduce the incidence of prolonged extubation times by 95% and 97%, respectively. Sevoflurane reduced the mean extubation time by 13% and reduced the SD by 8.7% relative to isoflurane. These reductions would reduce the incidence of prolonged extubation times by 51% and 35%, respectively. CONCLUSIONS: The pharmacoeconomics of volatile anesthetics are highly sensitive to measurement of relatively small time differences. Therefore, surgical facilities should use these values combined with their local data (e.g., mean baseline extubation times) when making evidence-based management decisions regarding pharmaceutical purchases and usage guidelines.

Efficacy and costs of 3 anesthetic regimens in the prevention of postoperative nausea and vomiting.

STUDY OBJECTIVE: The aim of the study was to compare the antiemetic efficacy and costs associated with 3 different anesthesia regimens used in gynecologic laparoscopy. DESIGN: This was a randomized, controlled study. SETTING: The study was conducted at a university hospital. PATIENTS: We studied 150 ASA physical status I or II patients, undergoing elective gynecologic laparoscopy with general anesthesia. INTERVENTION: Patients were allocated into the following 3 groups: group P-preoperative placebo tablet, propofol induction, propofol-air/O2 maintenance; group I + O-preoperative 8-mg ondansetron tablet, thiopental induction, isoflurane-N2O maintenance; group I (control)-preoperative placebo tablet, thiopental induction, isoflurane-N2O maintenance. MEASUREMENTS: The frequency of postoperative nausea and vomiting (PONV), number needed to treat to prevent PONV, and the costs of the anesthetic drugs to prevent PONV in one additional patient were evaluated. MAIN RESULTS: The frequency of PONV within the 24-hour study period was lowest in group I + O (P, 38%; I + O, 33%; and I, 59%; P < 0.05 I + O vs I). The number needed to treat was 5 in group P and 4 in group I + O, compared with group I. The median costs of anesthetic drugs to prevent PONV in one additional patient were $65 in group P and dollar 68 in group I + O, compared with group I. CONCLUSIONS: We conclude that in gynecologic laparoscopy, propofol-air/O2 anesthesia alone, and isoflurane-N2O anesthesia combined with an oral 8-mg dose of ondansetron had similar efficacy and costs to prevent PONV. Isoflurane-N2O anesthesia without ondansetron was less expensive, but was also less efficacious.

Cost minimisation and cost effectiveness in anaesthesia for total hip replacement surgery, in Belgium? A study comparing three general anaesthesia techniques.

The aim of the prospective randomised study is to compare the cost effectiveness of three general anaesthesia techniques for total hip replacement surgery and the cost minimisation by use of anaesthetics. For induction propofol was used in the three techniques. For maintenance, we used desflurane, or sevoflurane, or propofol. There was no significant difference in consumption of drugs for pain treatment, treatment of nausea and vomiting or cost of hospital stay or total cost for pharmacy. In terms of cost-effectiveness we can consider that the three techniques are similar. The cost of an i.v. technique was always higher than inhaled anaesthetics. The major cost in anaesthesia is the fee for the anaesthesiologist. But all in, the cost of anaesthesia was only 15.1% of the total cost of the procedure. Cost of inhaled or i.v. anaesthetics was 0.55% to 1.0% of the total cost. There was a discrepancy between the measured consumption of inhaled anaesthetics and the consumption (and cost) on the invoice. Cost minimisation based on anaesthetic medication is ridiculously by small considering the total cost of the procedure.

Inhalation anesthesiology and volatile liquid anesthetics: focus on isoflurane, desflurane, and sevoflurane.

Clinical pharmacists rarely are involved in the selection and dosing of anesthetic agents. However, when practicing evidence-based medicine in a cost-conscious health care system, optimizing drug therapy is imperative in all areas. Thus, we provide general information on anesthesiology, including the different types of breathing systems and the components of anesthesia machines. Modern inhalation anesthetics that are predominantly used in clinical practice include one gas--nitrous oxide--and new volatile liquid agents--isoflurane, desflurane, and sevoflurane. Desflurane and sevoflurane are the low-soluble inhalation anesthetics, and they offer some clinical advantages over isoflurane, such as fast induction and faster recovery with long procedures. However, efficient use of isoflurane can match the speed of induction and recovery of the other agents in certain cases. In addition, the patient characteristics, duration and type of procedure, type of breathing system, and efficiency in monitoring must be considered when selecting the most optimal therapy for each patient. Maximizing the clinical advantages of these agents while minimizing the waste of an institution's operating room and pharmacy budget requires an understanding of the characteristics, pharmacokinetics, and pharmacodynamics of these anesthetic agents and the collaborated effort from both the anesthesia and pharmacy departments. An anesthetic agent algorithm is provided as a sample decision-process tree for selecting among isoflurane, desflurane, and sevoflurane.

Pharmacoeconomic analysis of sevoflurane versus isoflurane anesthesia in elective ambulatory surgery.

This study investigated the economic aspects of sevoflurane and isoflurane anesthesia in 47 healthy women undergoing elective ambulatory surgery, as part of a randomized, prospective clinical trial. Patient records were analyzed for anesthetic; duration of surgery, anesthesia, and recovery room stay; and associated charges. Sevoflurane is shorter acting than isoflurane, but it was not associated with a shorter duration of anesthesia or surgical unit stay, or earlier hospital discharge. Total charges associated with sevoflurane anesthesia were greater than those for isoflurane ($2641 and $2230, respectively) and primarily related to prolonged anesthesia and surgical unit stay. A minor decrease in recovery room charges ($15) associated with earlier discharge was observed with sevoflurane (p>0.05), but the agent was not associated with lower hospital charges. Larger trials and assessment of other patient populations may show sevoflurane to be more pharmacoeconomically advantageous than isoflurane.

Inhalation versus total intravenous anesthesia for lumbar disc herniation: comparison of hemodynamic effects, recovery characteristics, and cost.

The clinical effects, recovery characteristics, and costs of total intravenous anesthesia (TIVA), sevoflurane, and isoflurane anesthesia have been measured in various out-patient operations, but have not been evaluated in patients undergoing laminectomy or discectomy. In the current study, the authors assessed the hemodynamic characteristics, recovery, and cost analyzes after laminectomy and discectomy operations, comparing TIVA, sevoflurane, and isoflurane anesthesia. Sixty American Society of Anesthesiologists I and II patients were randomly divided into three groups, each consisting of 20 patients. Group I received propofol-alfentanil, Group 2 received sevoflurane-N2O, and Group 3 received isoflurane-N2O. At the end of surgery, the anesthetics were discontinued, and recovery from anesthesia was assessed by measuring the time until spontaneous eye opening and the time until response to verbal commands. The drug and delivery costs were calculated in United States dollars. No significant differences were found in the demographic data. Heart rate and mean arterial pressure decreased significantly after induction of anesthesia in the TIVA group, compared to the two other groups ( P < .05 for both comparisons). The fastest recovery was seen in the TIVA group. Incidences of postoperative nausea, vomiting, and pain were significantly reduced after TIVA ( P < .05 for both comparisons). Thus, TIVA patients required fewer additional drugs and showed the lowest additional costs in the post-anesthesia care unit. However, the total cost was significantly higher in the TIVA group than in the sevoflurane and isoflurane groups (52.73 dollars, 29.99 dollars, and 24.14 dollars, respectively) ( P < .05). Total intravenous anesthesia was associated with the highest intraoperative cost but provided the most rapid recovery from anesthesia, and the least frequent postoperative side effects.

Cost-effectiveness of propofol anesthesia using target-controlled infusion compared with a standard regimen using desflurane.

The cost-effectiveness of propofol anesthesia using target-controlled infusion (TCI) versus a standard regimen using desflurane for anesthesia maintenance was analyzed. This observational study consisted of 100 inpatients 18 to 75 years old with an American Society of Anesthesiologists physical status of I or II who were scheduled for otological surgery lasting less than four hours. Patients received one of two treatments. The desflurane-maintenance group received propofol 2-4 mg/kg and sufentanil 0.15-0.30 microg (as the citrate)/kg. A constant fresh gas flow of 1 L/min was used during maintenance of anesthesia. The propofol-maintenance group received TCI propofol and an additional infusion of sufentanil. Anesthesia was induced with 0.15-0.30 microg/kg. One blinded evaluator assessed the postoperative recovery from anesthesia for all patients. The cost of drugs and medical devices used during the intraoperative and postoperative periods was calculated. Effectiveness was defined as the absence of postoperative nausea and vomiting (PONV), while the cost-effectiveness of each procedure was the cost per PONV-free episode. The efficiency of each procedure represented the production of effectiveness per dollar invested. Chi-square and t tests, sensitivity analysis, and logistic regression were also performed. The only intergroup difference detected was the frequency of PONV occurring in the early recovery phase (11 in the desflurane group versus 2 in the propofol group). Of those patients requiring antiemetic rescue, 9 were in the desflurane group and only 2 were in the propofol group (p < 0.05). The TCI propofol regimen was more expensive than the desflurane regimen ($45 versus $28 per patient, respectively) (p < 0.001). The differential cost-effectiveness ratio was $94.7 per PONV-free episode. PONV 24 hours after surgery and patient satisfaction were similar between groups. A standard regimen of desflurane was more cost-effective than TCI propofol for anesthesia maintenance in achieving PONV-free episodes.

Comparison of 3 different anesthetic techniques on 24-hour recovery after otologic surgical procedures.

Intravenous propofol anesthesia is better than inhalational anesthesia for otologic surgery, but cost and intraoperative movement make this technique prohibitive. This study compares a propofol sandwich anesthetic with a total propofol or inhalational anesthetic for otologic surgery to determine which produces the best perioperative conditions and least expense. One hundred twenty patients undergoing ear surgery were randomly chosen to receive an anesthetic with either isoflurane (INHAL), total propofol (TPROP), or propofol used in conjunction with isoflurane (PSAND). Postoperative wakeup and the incidence and severity of nausea, vomiting, and pain were compared among groups. Antiemetic administration and discharge times from recovery and the hospital were also compared. The groups were similar, but anesthesia times were longer in the INHAL group. Emergence from anesthesia after PSAND or TPROP was more rapid than after INHAL. Recovery during the next 24 hours was associated with less nausea and vomiting with PSAND than with INHAL. The cost of the PSAND anesthetic was similar to that of INHAL, and both were less than TPROP. PSAND anesthesia may be similar to TPROP and better than INHAL for otologic procedures. PSAND was less expensive than TPROP and produced a similar recovery profile and antiemetic effect in the 24-hour period after surgery.

Cost analysis of xenon anesthesia: a comparison with nitrous oxide-isoflurane and nitrous oxide-sevoflurane anesthesia.

STUDY OBJECTIVE: To determine the cost of xenon (Xe) anesthesia in relation to the anesthetic duration by conducting a cost analysis of this relatively expensive inhaled anesthetic. DESIGN: Cost analysis based on the literature on Xe anesthesia. SETTING: Anesthetic simulation based on data obtained in the operating rooms at a university hospital. PATIENTS: A 40-year-old, ASA physical status I adult patient model weighing 70 kg, undergoing elective minor surgery with endotracheal intubation and mechanical ventilation. INTERVENTIONS: Anesthesia was given in the following four techniques: 1) closed-circuit technique with Xe; 2) closed-circuit technique with nitrous oxide (N2O)-isoflurane; 3) semi-closed technique with N2O-isoflurane; and 4) semi-closed technique with N2O-sevoflurane. MEASUREMENTS AND MAIN RESULTS: Cost of each anesthetic technique was compared in U.S. dollars. The cost of Xe anesthesia was consistently higher than that of N2O-isoflurane or N2O-sevoflurane (for 240-min anesthesia; $356 with Xe, $52 with closed-circuit N2O-isoflurane, $94 with semi-closed N2O-isoflurane, and $84 with semi-closed N2O-sevoflurane). The major cost of Xe anesthesia was a result of the cost of priming and flushing; the cost of Xe used for its anesthetic effects was comparable with the other semi-closed techniques after 240 minutes. CONCLUSIONS: For Xe to be widely used in routine anesthesia, the methods of minimizing the amount of Xe necessary for priming and flushing must be developed.

Desflurane is not associated with faster operating room exit times in outpatients.

STUDY OBJECTIVE: To determine the influence of anesthetic technique and primary drug on operating room (OR) exit time (time between end of surgery until time patient exists the OR) after addition of desflurane to the hospital formulary. DESIGN: Prospective study. SETTING: Ambulatory surgery unit of a university hospital. PATIENTS: 1,568 outpatients requiring anesthesia. INTERVENTIONS: Addition of desflurane to the hospital formulary, and substitution of desflurane vaporizers for enflurane vaporizers in the ambulatory surgery unit. MEASUREMENTS AND MAIN RESULTS: The following information was recorded for all anesthetic encounters over a six-month time interval: demographics, duration of surgery, primary anesthetic technique, primary anesthetic drug, and exit times. General anesthesia was used in 907 patients [desflurane: 209 patients, isoflurane: 429 patients, halothane: 192 patients, propofol: 72 patients, other intravenous (i.v.): 5 patients], major conduction anesthesia (spinal and epidural) in 43 patients, peripheral nerve blocks in 90 patients, and i.v. sedation in 528 patients. The exit time was significantly greater ( < 0.05) in patients who received general anesthesia (mean +/- SEM 14 +/- 0.2 min) compared with spinal/epidural (8 +/- 0.7 min), nerve blocks (8 +/- 0.4 min) and i.v. sedation (7 +/- 0.2 min). Exit times were longer in older patients receiving general anesthesia (exit time = 12.3 + 0.04 x age, SE = 6.7 min, p < 0.0009), whereas exit times were shorter in older individuals receiving i.v. sedation (exit time = 8.97 - 0.038 x age, SE = 3.6 min, p < 0.0001). For patients receiving i.v. sedation, exit times were shorter as duration of surgery increased (exit time = 7.86 - 0.015 x duration of surgery, SE = 3.6 min, p < 0.0002). Primary anesthetic drug did not affect exit times. CONCLUSION: Regional anesthesia and i.v. sedation were associated with faster OR exit times compared with general anesthesia. Despite desflurane's shorter elimination kinetics and recovery characteristics, use of this drug did not result in shorter exit times.

Sevoflurane-N2O versus propofol/isoflurane-N2O during elective surgery using the laryngeal mask airway in adults.

STUDY OBJECTIVES: To compare a sevoflurane-nitrous oxide (N2O) general anesthetic technique with a standard technique of propofol for induction, and isoflurane-N2O for maintenance. DESIGN: Prospective, randomized study. SETTING: University-affiliated tertiary-care hospital. PATIENTS: 62 adults undergoing elective surgery using the laryngeal mask airway (LMA). INTERVENTIONS: Patients received either the standard technique of propofol for induction and isoflurane-N2O for maintenance (controls) or sevoflurane-N2O for both induction and maintenance of general anesthesia. MEASUREMENTS: Induction and emergence times, heart rate, blood pressure, oxygen saturation, and end-tidal carbon dioxide were recorded. MAIN RESULTS: Time to loss of consciousness was faster after propofol (mean +/- SEM: 51 +/- 3 sec) than after sevoflurane-N2O (85 +/- 10 sec; p < 0.05). Ready for surgery times, were however, similar between groups (10 +/- 1 vs. 11 +/- 1 min, respectively). All patients in the control group had apnea after LMA insertion compared with 4 patients in the sevoflurane-N2O group (p < 0.05). Heart rate was lower 5 and 10 minutes after LMA insertion in the sevoflurane-N2O group (69 +/- 3 and 66 +/- 3 bpm) versus the control group (81 +/- 3 bpm and 74 +/- 3 bpm, p < 0.05). After cessation of anesthetic gases, there were no differences in time to LMA removal, eye opening, or exiting the operating room (OR) between the control group (7, 8, and 10 min) and sevoflurane-N2O groups (7, 8, and 12 min, respectively). The majority of patients in both groups (92% to 97%) rated their anesthetic experience as excellent or good. CONCLUSIONS: Sevoflurane-N2O and propofol provided comparable conditions for LMA insertion. Sevoflurane-N2O was not associated with a faster return of consciousness or faster time to exit the OR compared with isoflurane-N2O.

Providing comfort to critically ill pediatric patients: isoflurane.

Isoflurane is a fluorinated ether used primarily as an inhalation anesthetic. Rapid titratable effects, limited metabolism, and a reliable mode of administration make isoflurane an appealing alternative to the use of intravenous sedatives and narcotics in critically ill patients requiring prolonged mechanical ventilation. This article, in reviewing this novel approach to management of patient discomfort, focuses on nursing practice issues and provides a critical analysis of isoflurane use in the intensive care unit.

Propofol vs isoflurane for neurosurgical anesthesia in Thai patients.

Sixty Thai patients, ASA class I-II, Glasgow coma score of 15 undergoing elective intracranial surgery were randomly assigned to 2 groups. In group I, 30 patients were induced with thiopental 3-5 mg/kg, intubation with succinylcholine 1-2 mg/kg and then maintained with 60 per cent N2O in O2, isoflurane and vecuronium as a muscle relaxant. In group II, 30 patients received fentanyl 50 micrograms, propofol 1.0-2.5 mg/kg for induction and vecuronium 0.08 mg/kg for intubation then maintained with 60 per cent N2O in O2, continuous infusion of propofol 2-12 mg/kg/h and vecuronium as a muscle relaxant. Controlled ventilation in both groups was set to maintain PET CO2 in the range of 28-35 mmHg. 3 patients (1 in group I and 2 in group II) were excluded from the study due to surgical problems. There was no statistical difference in age, sex, ASA status, weight, duration of anesthesia. Group II had a more stable systolic BP, Diastolic BP and Pulse rate than Group I during induction and emergence from anesthesia. Glasgow coma scores in the recovery period, Group II had higher scores than Group I at 5 and 15 minutes but not at 30 minutes. Mean recovery times (eye opening) was 14.03 +/- 4.85 minutes in group I which is significantly different from 10 +/- 5.17 minutes in group II. The cost of anesthesia in group II was 1.3 times that of group I. In conclusion, although neurosurgical anesthesia for Thai patients with fentanyl-propofol technique produces more stable blood pressure during intubation and emergence, rapid recovery from anesthesia and a higher Glasgow coma score, the cost of anesthesia is more expensive. Furthermore, this technique is more difficult and needs more experience.