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.

Economic Evaluation of Pharmacologic Pre- and Postconditioning With Sevoflurane Compared With Total Intravenous Anesthesia in Liver Surgery: A Cost Analysis.

BACKGROUND: Pharmacologic pre- and postconditioning with sevoflurane compared with total IV anesthesia in patients undergoing liver surgery reduced complication rates as shown in 2 recent randomized controlled trials. However, the potential health economic consequences of these different anesthesia regimens have not yet been assessed. METHODS: An expostcost analysis of these 2 trials in 129 patients treated between 2006 and 2010 was performed. We analyzed direct medical costs for in-hospital stay and compared pharmacologic pre- and postconditioning with sevoflurane (intervention) with total IV anesthesia (control) from the perspective of a Swiss university hospital. Year 2015 costs, converted to US dollars, were derived from hospital cost accounting data and compared with a multivariable regression analysis adjusting for relevant covariables. Costs with negative prefix indicate savings and costs with positive prefix represent higher spending in our analysis. RESULTS: Treatment-related costs per patient showed a nonsignificant change by -12,697 US dollars (95% confidence interval [CI], 10,956 to -36,352; P = .29) with preconditioning and by -6139 US dollars (95% CI, 6723 to -19,000; P = .35) with postconditioning compared with the control group. Results were robust in our sensitivity analysis. For both procedures (control and intervention) together, major complications led to a significant increase in costs by 86,018 US dollars (95% CI, 13,839-158,198; P = .02) per patient compared with patients with no major complications. CONCLUSIONS: In this cost analysis, reduced in-hospital costs by pharmacologic conditioning with sevoflurane in patients undergoing liver surgery are suggested. This possible difference in costs compared with total IV anesthesia is the result of reduced complication rates with pharmacologic conditioning, because major complications have significant cost implications.

Irrigation with Liquid Sevoflurane and Healing of a Postoperative, Recurrent Epidural Infection: A Potential Cost-Saving Alternative.

BACKGROUND: The general inhalation anesthetic sevoflurane can be used for the topical treatment of complicated wounds. It is applied in liquid form and may be used to irrigate the inside of cavities. Sevoflurane also exhibits in vitro antimicrobial activity. Therefore, sevoflurane may be used as an alternative to typical antibiotic or surgical treatment of complicated, localized infections. CASE DESCRIPTION: The case of a 61-year-old male patient who suffered a cranioencephalic trauma 18 years previously is presented. The patient underwent surgeries related to the trauma on numerous occasions. To date, he has suffered various recurrent epidural abscesses, which have been treated with surgical cleaning and antibiotic treatment. In the most recent episode, he presented a frontal epidural abscess 25 mm in diameter with fistulization of the skin. The patient gave written informed consent to be treated with sevoflurane irrigation, and the Pharmacy Service authorized the off-label use. Sevoflurane was applied via a catheter placed inside the cavity during weekly outpatient procedures. The procedures began 8 weeks after the clinically and radiologically verified recovery of the abscess. By avoiding surgery and the associated hospital admission, this novel alternative may prevent patient morbidity and, furthermore, may produce important economic savings. CONCLUSIONS: The treatment of complicated wounds with liquid sevoflurane may be an effective and economically efficient clinical alternative for some patients.

Economic and Environmental Considerations During Low Fresh Gas Flow Volatile Agent Administration After Change to a Nonreactive Carbon Dioxide Absorbent.

BACKGROUND: Reducing fresh gas flow (FGF) during general anesthesia reduces costs by decreasing the consumption of volatile anesthetics and attenuates their contribution to greenhouse gas pollution of the environment. The sevoflurane FGF recommendations in the Food and Drug Administration package insert relate to concern over potential toxicity from accumulation in the breathing circuit of compound A, a by-product of the reaction of the volatile agent with legacy carbon dioxide absorbents containing strong alkali such as sodium or potassium hydroxide. Newer, nonreactive absorbents do not produce compound A, making such restrictions moot. We evaluated 4 hypotheses for sevoflurane comparing intervals before and after converting from a legacy absorbent (soda lime) to a nonreactive absorbent (Litholyme): (1) intraoperative FGF would be reduced; (2) sevoflurane consumption per minute of volatile agent administration would be reduced; (3) cost savings due to reduced sevoflurane consumption would (modestly) exceed the incremental cost of the premium absorbent; and (4) residual wastage in discarded sevoflurane bottles would be <1%. METHODS: Inspired carbon dioxide (PICO2), expired carbon dioxide, oxygen, air, and nitrous oxide FGF, inspired volatile agent concentrations (FiAgent), and liquid volatile agent consumption were extracted from our anesthesia information management system for 8 4 week intervals before and after the absorbent conversion. Anesthesia providers were notified by e-mail and announcements at Grand Rounds about the impending change and were encouraged to reduce their average intraoperative sevoflurane FGF to 1.25 L/min. Personalized e-mail reports were sent every 4 weeks throughout the study period regarding the average intraoperative FGF (i.e., from surgery begin to surgery end) for each agent. Batch means methods were used to compare FGF, volatile agent consumption, net cost savings, and residual sevoflurane left in bottles to be discarded in the trash after filling vaporizers. The time from reaching a PICO2 = 3 mm Hg for 3 minutes until agent exhaustion (PICO2 = 5 mm Hg for 5 minutes) was evaluated. RESULTS: A total of N = 20,235 cases were analyzed (80.2% sevoflurane, 15.1% desflurane, and 4.7% isoflurane). Intraoperative FGF was reduced for cases in which sevoflurane was administered by 435 mL/min (95% confidence interval [CI], 391 to 479 mL/min; P < 10). Hypothesis 1 was accepted. Sevoflurane consumption per minute of administration decreased by 0.039 mL/min (95% CI, 0.029 to 0.049 mL/min; P < 10) after the change to the nonreactive absorbent. Hypothesis 2 was accepted. The difference in mean cost for the sum of the sevoflurane and absorbent purchases for each of the 10 4-week intervals before and after the absorbent switch was -$293 per 4-week interval (95% CI, -$2853 to $2266; P = 0.81). Hypothesis 3 was rejected. The average amount of residual sevoflurane per bottle was 0.67 ± 0.06 mL (95% CI, 0.54 to 0.81 mL per bottle; P < 10 vs 2.5 mL). Hypothesis 4 was accepted. Once the PICO2 reached 3 mm Hg for at least 3 consecutive minutes, the absorbent became exhausted within 95 minutes in most (i.e., >50%) canisters. CONCLUSIONS: We showed that an anesthesia department can transition to a premium, nonreactive carbon dioxide absorbent in a manner that is at least cost neutral by reducing FGF below the lower flow limits recommended in the sevoflurane package insert. This was achieved, in part, by electronically monitoring PICO2, automatically notifying the anesthesia technicians when to change the absorbent, and by providing personalized feedback via e-mail to the anesthesia providers.

A simple intervention to reduce the anesthetic pharmacy budget; the effect of price list stickers placed on vaporizers.

STUDY OBJECTIVE: The study objective is to investigate the effects of a simple price list sticker placed on vaporizers on anesthetic use and costs. The price list only showed the cost per hour of the annually most expensive drugs, which had a low-cost alternative. DESIGN: The design is a prospective database study with historical controls. SETTING: The setting is at operating rooms. PATIENTS: All patients are undergoing a surgical procedure under anesthesia in both study periods, except cardiothoracic and day care patients. INTERVENTIONS: The intervention is application of a price list sticker on the vaporizers. MEASUREMENTS: Monthly cost and amount of anesthetic agents used during the 9 months before and after the intervention. MAIN RESULTS: After application of the price stickers, the use of both the annually most expensive agents and the anesthetic budget decreased substantially. Most notable was a decrease of 28% in the use of sevoflurane. CONCLUSIONS: Price sticker on vaporizers may be an effective, simple, and cheap method to reduce anesthetic costs.

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.

Sevoflurane induction procedure: cost comparison between fixed 8% versus incremental techniques in pediatric patients.

This study compared 2 well-accepted and safe methods of pediatric inhalation induction using sevoflurane. Incremental and fixed 8% induction methods were evaluated for economic outcomes by comparing the amount of liquid sevoflurane consumed. We also tried to establish the relation between cost of induction and demographic parameters in both groups. One hundred pediatric patients scheduled for ophthalmologic examination under anesthesia were randomly divided into 2 equal groups. The amount of sevoflurane consumed in both groups was computed using the Dion method. Although the time to loss of consciousness was significantly lower using the 8% method (75.98 vs 135 seconds), the liquid sevoflurane consumption using the incremental method (2.25 mL) was almost half that of the fixed 8% method (4.46 mL). The overall procedural cost of induction (loss of consciousness plus intravenous cannulation and insertion of a laryngeal mask airway) was also almost double using the fixed 8% method. Use of the incremental method preferably over the fixed 8% method could save almost $18 US for each procedure. The volume of sevoflurane consumed during anesthesia induction was found to be independent of age, weight, or sex of pediatric patients. Both induction methods proved to be equally safe and acceptable to the patients.

[Impact of the decrease of nitrous oxide use on the consumption of halogenated agents]. / Impact de la diminution d'utilisation du protoxyde d'azote sur la consommation d'agents halogénés.

OBJECTIVE: Nitrous oxide (N2O) toxicity and its impact on pollution lead to restrict its use. A decrease of N2O consumption should increase the hypnotic inhaled consumption. This monocentric study estimated consumptions and costs of halogenated agents (HA) and N2O over 5 years when the N2O consumption was reduced. STUDY DESIGN: Retrospective from a computerized database. PATIENTS: Between 2006 and 2010, 34,097 procedures were studied after two meetings exposing the risks of the N2O. METHODS: At the end of anesthesia, consumptions of hypnotic agents (millilitres transmitted by the injectors and the blender) were archived in the database. The annual consumption of agents was obtained by adding the individual consumptions, then divided by the annual number of cases. The costs were given by the hospital pharmacy from invoices. RESULTS: N2O consumption per anesthesia constantly decreased during the study, from 75.1L by act to 22.7L. The sum of the annual consumptions of N2O and air did not change suggesting that total fresh gas flow remained stable. Between 2006 and 2010, the sevoflurane consumption by act increased by 25%, from 16.5 to 20.6mL, and desflurane consumption by 37%, from 46.1 to 63.1mL by patient. The costs of the administration of hypnotic agents remained stable. CONCLUSION: N2O consumption decrease had an impact on the consumption of HA. The cost reduction of the N2O was counterbalanced by the increase of halogenated vapor cost. The profit of the ecological impact of the reduction in N2O use could be quantified.

Financial and environmental costs of manual versus automated control of end-tidal gas concentrations.

Emerging technologies that reduce the economic and environmental costs of anaesthesia have had limited assessment. We hypothesised that automated control of end-tidal gases, a new feature in anaesthesia machines, will consistently reduce volatile agent consumption cost and greenhouse gas emissions. As part of the planned replacement of anaesthesia machines in a tertiary hospital, we performed a prospective before and after study comparing the cost and greenhouse gas emissions of isoflurane, sevoflurane and desflurane when using manual versus automated control of end-tidal gases. We analysed 3675 general anaesthesia cases with inhalational agents: 1865 using manual control and 1810 using automated control. Volatile agent cost was $18.87/hour using manual control and $13.82/hour using automated control: mean decrease $5.05/hour (95% confidence interval: $0.88-9.22/hour, P=0.0243). The 100-year global warming potential decreased from 23.2 kg/hour of carbon dioxide equivalents to 13.0 kg/hour: mean decrease 10.2 kg/hour (95% confidence interval: 2.7-17.7 kg/hour, P=0.0179). Automated control reduced costs by 27%. Greenhouse gas emissions decreased by 44%, a greater than expected decrease facilitated by a proportional reduction in desflurane use. Automated control of end-tidal gases increases participation in low flow anaesthesia with economic and environmental benefits.

The Hip Fracture Surgery in Elderly Patients (HIPELD) study: protocol for a randomized, multicenter controlled trial evaluating the effect of xenon on postoperative delirium in older patients undergoing hip fracture surgery.

BACKGROUND: Strategies to protect the brain from postoperative delirium (POD) after hip fracture are urgently needed. The development of delirium often is associated with the loss of independence, poor functional recovery, and increased morbidity, as well as increases in length of hospital stay, discharges to nursing facilities, and healthcare costs. We hypothesize that xenon may reduce the burden of POD, (i) by avoiding the need to provide anesthesia with a drug that targets the γ-amino-butyric acid (GABA)A receptor and (ii) through beneficial anesthetic and organ-protective effects. METHODS AND DESIGN: An international, multicenter, phase 2, prospective, randomized, blinded, parallel group and controlled trial to evaluate the incidence of POD, diagnosed with the Confusion Assessment Method (CAM), in older patients undergoing hip fracture surgery under general anesthesia with xenon or sevoflurane, for a period of 4 days post surgery (primary outcome) is planned. Secondary objectives are to compare the incidence of POD between xenon and sevoflurane, to evaluate the incidence of POD from day 5 post surgery until discharge from hospital, to determine the time to first POD diagnosis, to evaluate the duration of POD, to evaluate the evolution of the physiological status of the patients in the postoperative period, to evaluate the recovery parameters, to collect preliminary data to evaluate the economical impact of POD in the postoperative period and to collect safety data. Patients are eligible if they are older aged (≥ 75 years) and assigned to a planned hip fracture surgery within 48 h after the hip fracture. Furthermore, patients need to be willing and able to complete the requirements of this study including the signature of the written informed consent. A total of 256 randomized patients in the 10 participating centers will be recruited, that is, 128 randomized patients in each of the 2 study groups (receiving either xenon or sevoflurane). TRIAL REGISTRATION: EudraCT Identifier: 2009-017153-35; ClinicalTrials.gov Identifier: NCT01199276.

Efficiency and safety of inhalative sedation with sevoflurane in comparison to an intravenous sedation concept with propofol in intensive care patients: study protocol for a randomized controlled trial.

BACKGROUND: State of the art sedation concepts on intensive care units (ICU) favor propofol for a time period of up to 72 h and midazolam for long-term sedation. However, intravenous sedation is associated with complications such as development of tolerance, insufficient sedation quality, gastrointestinal paralysis, and withdrawal symptoms including cognitive deficits. Therefore, we aimed to investigate whether sevoflurane as a volatile anesthetic technically implemented by the anesthetic-conserving device (ACD) may provide advantages regarding 'weaning time', efficiency, and patient's safety when compared to standard intravenous sedation employing propofol. METHOD/DESIGN: This currently ongoing trial is designed as a two-armed, monocentric, randomized prospective phase II study including intubated intensive care patients with an expected necessity for sedation exceeding 48 h. Patients are randomly assigned to either receive intravenous sedation with propofol or sevoflurane employing the ACD. Primary endpoint is the comparison of the 'weaning time' defined as the time required from discontinuation of the sedating agent until sufficient spontaneous breathing occurs. Moreover, sedation depth evaluated by Richmond Agitation Sedation Scale and parameters of patient's safety (that is, vital signs, laboratory monitoring of organ function) as well as the duration of mechanical ventilation and overall stay on the ICU are analyzed and compared. An intention-to-treat analysis will be carried out with all patients for whom it will be possible to define a wake-up time. In addition, a per-protocol analysis is envisaged. Completion of patient recruitment is expected by the end of 2012. DISCUSSION: This clinical study is designed to evaluate the impact of sevoflurane during long-term sedation of critically ill patients on 'weaning time', efficiency, and patient's safety compared to the standard intravenous sedation concept employing propofol. TRIAL REGISTRATION: EudraCT2007-006087-30; ISRCTN90609144.

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.

[Efficacy, safety and cost of sedation with sevoflurane in intensive care unit]. / Efficacité, tolérance et coût d'une sédation par sévoflurane en réanimation.

OBJECTIVES: To study efficacy, systemic and cerebral haemodynamic, and cost of sedation with sevoflurane after midazolam failure. STUDY DESIGN: Prospective observational study in a mixed intensive care unit. PATIENTS AND METHODS: Mechanically ventiled patients in whom deep sedation failed (Ramsay score<5 despite midazolam 10mg/h and fentanyl 400µg/h) were enrolled. Sedation with sevoflurane and fentanyl (200µg/h) was performed during 48 hours. Sevoflurane was administered with a dedicated filter (AnaConDa™) and sevoflurane infusion rate was adjusted in order to achieve a Ramsay score ≥5. Ramsay score, mean arterial blood pressure, norepinephrine dose/24h, intracranial pressure and cerebral perfusion pressure in patients with brain injury were measured. Directs costs for sedation were calculated. An analysis of variance for repeated measures compared values between D0 (intravenous sedation), D1 and D2 (inhaled sedation). RESULTS: Twenty-five patients (age=51 [38-63], SAPS II=43 [33-49]) were enrolled. Ramsay score was 4 [4,5] at D0 and 6 [6] at D1 and D2 (P<0.05 vs D0). Mean arterial pressure was significantly lower at D1 (80 [73-86] mmHg) as compared to D0 (84 [77-92] mmHg) and D2 (84 [78-91] mmHg) (P<0,05). Norepinephrine consumption was lower at D2 as compared to D1 (P<0,05). Intracranial pressure was lower at D1 (9 [5-13] mmHg) and D2 (11 [7-15] mmHg) as compared to D0 (12 [7-17] mmHg) (P<0.05). PPC was stable at D1 and increased at D2. Directs costs were significantly increased with sevoflurane. CONCLUSION: Sevoflurane is an effective and safe alternative to midazolam in ICU patients associated with a moderate increase in costs.

Pharmacoeconomics of volatile inhalational anaesthetic agents: an 11-year retrospective analysis.

With continuously increasing expenditure on health care resources, various cost containment strategies have been suggested in regard to controlling the cost of inhalational anaesthetic agents. We performed a cost identification analysis assessing inhalational anaesthetic agent expenditure at a tertiary level hospital, along with an evaluation of strategies to contain the cost of these agents. The number of bottles of isoflurane, sevoflurane and desflurane used during the financial years 1997 to 2007 was retrospectively determined and the acquisition costs and cumulative drug expenditure calculated. Pharmacoeconomic modelling using low fresh gas flow anaesthesia was performed to evaluate practical methods of cost reduction. The use of isoflurane decreased from 384 bottles during 1997 to 204 in 2007. In contrast, use of sevoflurane increased from 226 bottles during 1998 to 875 during 2007. Desflurane use increased from 34 bottles per year during 2002 (its year of introduction) to 163 bottles per year in 2007. While the inflation-adjusted cumulative expenditure for these inhalational agents (Australian dollars) increased from $132,000 in 1997 to over $326,000 in 2007, an increase of 168%, patient workload over the same period increased by only 11%. Pharmacoeconomic modelling demonstrated that sevoflurane at 2 l/minute costs 19 times more than isoflurane at 0.5 l/minute. For the financial years 1997 to 2007, we found a progressive shift from the cheaper isoflurane to the more expensive agents, sevoflurane and desflurane, a shift associated with marked increases in costs. Low flow anaesthesia with isoflurane is one strategy to reduce costs.

Cuffed endotracheal tubes in children reduce sevoflurane and medical gas consumption and related costs.

BACKGROUND: This study aims to evaluate sevoflurane and anaesthetic gas consumption using uncuffed vs. cuffed endotracheal tubes (ETT) in paediatric surgical patients. METHODS: Uncuffed or cuffed ETT were used in paediatric patients (newborn to 5 years) undergoing elective surgery in a randomized order. Duration of assessment, lowest possible fresh gas flow (minimal allowed FGF: 0.5 l/min) and sevoflurane concentrations used were recorded. Consumption and costs for sevoflurane and medical gases were calculated. RESULTS: Seventy children (35 uncuffed ETT/35 cuffed ETT), aged 1.73 (0.01-4.80) years, were enrolled. No significant differences in patient characteristics, study period and sevoflurane concentrations used were found between the two groups. Lowest possible FGF was significantly lower in the cuffed ETT group [1.0 (0.5-1.0) l/min] than in the uncuffed ETT group [2.0 (0.5-4.3) l/min], P<0.001. Sevoflurane consumption per patient was 16.1 (6.4-82.8) ml in the uncuffed ETT group and 6.2 (1.1-14.9) ml in the cuffed ETT group, P=0.003. Medical gas consumption was 129 (53-552) l in the uncuffed ETT group vs. 46 (9-149) l in the cuffed ETT group, P<0.001. The total costs for sevoflurane and medical gases were 13.4 (6.0-67.3)euro/patient in the uncuffed ETT group and 5.2 (1.0-12.5)euro/patient in the cuffed ETT group, P<0.001. CONCLUSIONS: The use of cuffed ETT in children significantly reduced the costs of sevoflurane and medical gas consumption during anaesthesia. Increased costs for cuffed compared with uncuffed ETT were completely compensated by a reduction in sevoflurane and medical gas consumption.

Managing inhaled anesthesia: challenges from a health-system pharmacist's perspective.

PURPOSE: To discuss the challenges that health-system pharmacists face in managing the use and costs of inhaled anesthesia in the operating room (OR), the characteristics of inhaled anesthesia agents, systems for delivering inhaled anesthesia, and the role of inhaled anesthetics in fast-track recovery after surgery. SUMMARY: Inhaled anesthetic agents are the most common drugs used in general anesthesia and are a substantial part of the anesthetic drug budget in health systems. Challenges for health-system pharmacists in managing costs associated with these agents include the lack of a dedicated OR pharmacy, limited access to the OR, unfamiliarity with some of the medications used in the OR, and difficulty quantifying inhaled anesthetic drug use. The three inhaled anesthesia agents currently used in the United States have proven to be safe and effective. These agents have differences in solubility in blood and tissues, which affect onset, absorption, and excretion. Isoflurane has the highest solubility in blood and tissues, which may result in slower recovery. Lower solubility allows for a faster recovery. The two newest agents on the market, sevoflurane and desflurane, both have low solubility, with desflurane having lower solubility than sevoflurane. Sevoflurane has the advantage of low pungency and is not associated with respiratory irritation. As a cost-savings initiative, the inhalation agents may be used with low flow rates, which minimizes the amount of inhaled anesthetic used. In addition, using the less soluble inhaled anesthetic agents as part of a fast-track approach will accelerate recovery by reducing time to emergence and recovery. This approach can potentially reduce costs to the institution. CONCLUSION: Understanding the differences in characteristics and delivery of the inhaled anesthesia agents will enable health-system pharmacists to collaborate with anesthesia care providers to better manage the use and costs of these agents.

Economic considerations in the use of inhaled anesthetic agents.

PURPOSE: To describe the components of and factors contributing to the costs of inhaled anesthesia, basis for quantifying and comparing these costs, and practical strategies for performing pharmacoeconomic analyses and reducing the costs of inhaled anesthetic agents. SUMMARY: Inhaled anesthesia can be costly, and some of the variable costs, including fresh gas flow rates and vaporizer settings, are potential targets for cost savings. The use of a low fresh gas flow rate maximizes rebreathing of exhaled anesthetic gas and is less costly than a high flow rate, but it provides less control of the level of anesthesia. The minimum alveolar concentration (MAC) hour is a measure that can be used to compare the cost of inhaled anesthetic agents at various fresh gas flow rates. Anesthesia records provide a sense of patterns of inhaled anesthetic agent use, but the amount of detail can be limited. Cost savings have resulted from efforts to reduce the direct costs of inhaled anesthetic agents, but reductions in indirect costs through shortened times to patient recovery and discharge following the judicious use of these agents are more difficult to demonstrate. The patient case mix, fresh gas flow rates typically used during inhaled anesthesia, availability and location of vaporizers, and anesthesia care provider preferences and practices should be taken into consideration in pharmacoeconomic evaluations and recommendations for controlling the costs of inhaled anesthesia. CONCLUSION: Understanding factors that contribute to the costs of inhaled anesthesia and considering those factors in pharmacoeconomic analyses and recommendations for use of these agents can result in cost savings.