Inhalation anaesthesia is cost-effective for ambulatory surgery: a clinical comparison with propofol during elective knee arthroscopy

Total intravenous anesthesia vs inhalational anesthesia in patients undergoing surgery under general anesthesia. Cost-minimization study

Introduction: The methods most frequently used at the present time in Colombia for the administration of general anesthesia are based on halogenated and intravenous drugs. However, in view of the lack of differential clinical outcomes, the existence of cost variations between the two is not clear. Objective: To determine the expected cost of the use of both techniques in patients taken to surgery, within the framework of the Colombian national health system. Methods: A cost minimization study was carried out using the decision tree as the analytical model. A time frame of 6 postoperative hours was used as the assumption. Only direct healthcare-related costs were included using a case study approach. An econometric model was used based on the frequency with which each technology is applied and the type of drug used, and a deterministic and probabilistic sensitivity analysis was performed. Results: For the case study, total intravenous anesthesia (TIVA) is more costly than the inhalational technique, with an incremental cost of $102,718 per patient. The deterministic analysis shows that both the incidence of postoperative nausea and vomiting (PONV) as well as the use of target controlled infusion (TCI) techniques are the main cost determinants. The probabilistic analysis shows that the cost difference can even be nil in more than 50% of the simulated settings, when the difference in the risk of PONV is higher. Conclusions: Although the total intravenous technique can be more costly than the inhalational technique, this difference is offset by a lower cost of the postanesthesia care unit, given the lower risk of postoperative nausea and vomiting.

Effect of Timing of Intravenous Fentanyl Administration on the Incidence of Posttonsillectomy Nausea and Vomiting

OBJECTIVE/HYPOTHESIS

Fentanyl is commonly administered toward the end of tonsillectomy to prevent emergence delirium and reduce postoperative pain. However, it can delay emergence from anesthesia and increase the risk of postoperative nausea and vomiting (PONV). The goal of our study was to compare the risk of PONV based on the timing of fentanyl administration at the end of tonsillectomy in children.

STUDY DESIGN

Prospective, double-blind, randomized controlled trial.

METHODS

One hundred forty patients aged 3 to 7 years undergoing tonsillectomy were divided into two groups. Fentanyl (1 μg/kg) was administered at the end of surgery in group 1 (n = 70) and at 10 to 15 minutes before the end of surgery in group 2 (n = 70). Time to regular breathing and time to emergence from anesthesia were measured from the end of surgery. PONV and pediatric anesthesia emergence delirium scale scores were assessed every 10 minutes after admission to the postanesthesia care unit.

RESULTS

Incidences of PONV (2.9% vs. 2.9%, P > .99) and emergence delirium (11.4% vs. 5.7%, P = .23) were not significantly different between the two groups. Time to regular breathing (mean difference = 2.3 minutes; 95% confidence interval [CI]: 0.9 to 3.7 minutes) and time to emergence (median difference = 6.5 minutes; 95% CI, 2.5 to 10.5 minutes) were significantly longer in group 1 than in group 2.

CONCLUSIONS

Although there was no beneficial effect on PONV, recovery of regular breathing and consciousness was quicker with earlier fentanyl administration. Emergence delirium was well-controlled, similar to that with fentanyl administration at the end of surgery.

LEVEL OF EVIDENCE

1b Laryngoscope, 2020.

Sources of Variation in Anesthetic Drug Costs

BACKGROUND

Increasing attention has been focused on health care expenditures, which include anesthetic-related drug costs. Using data from 2 large academic medical centers, we sought to identify significant contributors to anesthetic drug cost variation.

METHODS

Using anesthesia information management systems, we calculated volatile and intravenous drug costs for 8 types of inpatient surgical procedures performed from July 1, 2009, to December 31, 2011. For each case, we determined patient age, American Society of Anesthesiologists (ASA) physical status, gender, institution, case duration, in-room provider, and attending anesthesiologist. These variables were then entered into 2 fixed-effects linear regression models, both with logarithmically transformed case cost as the outcome variable. The first model included duration, attending anesthesiologist, patient age, ASA physical status, and patient gender as independent variables. The second model included case type, institution, patient age, ASA physical status, and patient gender as independent variables. When all variables were entered into 1 model, redundancy analyses showed that case type was highly correlated (R = 0.92) with the other variables in the model. More specifically, a model that included case type was no better at predicting cost than a model without the variable, as long as that model contained the combination of attending anesthesiologist and case duration. Therefore, because we were interested in determining the effect both variables had on cost, 2 models were created instead of 1. The average change in cost resulting from each variable compared to the average cost of the reference category was calculated by first exponentiating the β coefficient and subtracting 1 to get the percent difference in cost. We then multiplied that value by the mean cost of the associated reference group.

RESULTS

A total of 5504 records were identified, of which 4856 were analyzed. The median anesthetic drug cost was $38.45 (25th percentile = $23.23, 75th percentile = $63.82). The majority of the variation was not described by our models-35.2% was explained in the model containing case duration, and 32.3% was explained in the model containing case type. However, the largest sources of variation our models identified were attending anesthesiologist, case type, and procedure duration. With all else held constant, the average change in cost between attending anesthesiologists ranged from a cost decrease of $41.25 to a cost increase of $95.67 (10th percentile = -$19.96, 90th percentile = +$20.20) when compared to the provider with the median value for mean cost per case. The average change in cost between institutions was significant but minor ($5.73).

CONCLUSIONS

The majority of the variation was not described by the models, possibly indicating high per-case random variation. The largest sources of variation identified by our models included attending anesthesiologist, procedure type, and case duration. The difference in cost between institutions was statistically significant but was minor. While many prior studies have found significant savings resulting from cost-reducing interventions, our findings suggest that because the overall cost of anesthetic drugs was small, the savings resulting from interventions focused on the clinical practice of attending anesthesiologists may be negligible, especially in institutions where access to more expensive drugs is already limited. Thus, cost-saving efforts may be better focused elsewhere.

Emergence times and airway reactions during general anaesthesia with remifentanil and a laryngeal mask airway: A multicentre randomised controlled trial

BACKGROUND

Avoidance of airway complications and rapid emergence from anaesthesia are indispensable for the use of a laryngeal mask airway (LMA). Evidence from adequately powered randomised studies with a low risk of bias for the optimal anaesthetic in this context is limited.

OBJECTIVE

We tested the hypothesis that when using remifentanil-based intra-operative analgesia, desflurane would be the most suitable anaesthetic: with noninferiority in the occurrence of upper airway complications and superiority in emergence times compared with sevoflurane or propofol.

DESIGN

A randomised, multicentre, partially double-blinded, three-arm, parallel-group study.

SETTING

Two university and two regional German hospitals, from February to October 2015.

PATIENTS

A total of 352 patients (age 18 to 75 years, ASA physical status I to III, BMI less than 35 kg m⁻² and fluent in German) were enrolled in this study. All surgery was elective with a duration of 0.5 to 2 h, and general anaesthesia with a LMA was feasible.

INTERVENTION

The patients were randomised to receive desflurane, sevoflurane or propofol anaesthesia.

MAIN OUTCOME MEASURES

This study was powered for the primary outcome ‘time to state date of birth’ and the secondary outcome ‘intra-operative cough’. Time to emergence from anaesthesia and the incidence of upper airway complications were assessed on the day of surgery.

RESULTS

The primary outcome was analysed for 343 patients: desflurane (n=114), sevoflurane (n=111) and propofol (n=118). The desflurane group had the fastest emergence. The mean (± SD) times to state the date of birth following desflurane, sevoflurane and propofol were 8.1 ± 3.6, 10.1 ± 4.0 and 9.8 ± 5.1 min, respectively (P < 0.01). There was no difference in upper airway complications (cough and laryngospasm) across the groups, but these complications were less frequent than in previous studies.

CONCLUSION

When using a remifentanil infusion for intra-operative analgesia in association with a LMA, desflurane was associated with a significantly faster emergence and noninferiority in the incidence of intra-operative cough than either sevoflurane or Propofol.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02322502; EudraCT identifier: 2014-003810-96.

Analysis of anesthesia-controlled operating room time after propofol-based total intravenous anesthesia compared with desflurane anesthesia in functional endoscopic sinus surgery

Anesthesia technique may contribute to the improvement of operation room (OR) efficiency by reducing anesthesia-controlled time. We compared the difference between propofol-based total intravenous anesthesia (TIVA) and desflurane anesthesia (DES) for functional endoscopic sinus surgery (FESS) undergoing general anesthesiaWe performed a retrospective study using data collected in our hospital to compare the anesthesia-controlled time of FESS using either TIVA via target-controlled infusion with propofol/fentanyl or DES/fentanyl-based anesthesia between January 2010 and December 2011. The various time intervals (surgical time, anesthesia time, extubation time, total OR stay time, post anesthesia care unit [PACU] stay time) and the percentage of prolonged extubation were compared between the 2 anesthetic techniques.We included data from 717 patients, with 305 patients receiving TIVA and 412 patients receiving DES. An emergence time >15 minutes is defined as prolonged extubation. The extubation time was faster (8.8 [3.5] vs. 9.6 [4.0] minutes; P = .03), and the percentage of prolonged extubation was lower (7.5% vs. 13.6%, risk difference 6.1%, P < .001) in the TIVA group than in the DES group. However, there was no significant difference between ACT, total OR stay time, and PACU stay time.In our hospital, propofol-based TIVA by target-controlled infusion provide faster emergence and lower chance of prolonged extubation compared with DES anesthesia in FESS. However, the reduction in extubation time may not improve OR efficiency.

Planning for operating room efficiency and faster anesthesia wake-up time in open major upper abdominal surgery

Reducing anesthesia-controlled time (ACT) may improve operation room (OR) efficiency result from different anesthetic techniques. However, the information about the difference in ACT between desflurane (DES) anesthesia and propofol-based total intravenous anesthesia (TIVA) techniques for open major upper abdominal surgery under general anesthesia (GA) is not available in the literature.This retrospective study uses our hospital database to analyze the ACT of open major upper abdominal surgery without liver resection after either desflurane/fentanyl-based anesthesia or TIVA via target-controlled infusion with fentanyl/propofol from January 2010 to December 2011. The various time intervals including waiting for anesthesia time, anesthesia time, surgical time, extubation time, exit from OR after extubation, total OR time, and postanesthetic care unit (PACU) stay time and percentage of prolonged extubation (≥15 minutes) were compared between these 2 anesthetic techniques.We included data from 343 patients, with 159 patients receiving TIVA and 184 patients receiving DES. The only significant difference is extubation time, TIVA was faster than the DES group (8.5 ± 3.8 vs 9.4 ± 3.7 minutes; P = 0.04). The factors contributed to prolonged extubation were age, gender, body mass index, DES anesthesia, and anesthesia time.In our hospital, propofol-based TIVA by target-controlled infusion provides faster emergence compared with DES anesthesia; however, it did not improve OR efficiency in open major abdominal surgery. Older, male gender, higher body mass index, DES anesthesia, and lengthy anesthesia time were factors that contribute to extubation time.

Airway reactions and emergence times in general laryngeal mask airway anaesthesia: a meta-analysis

BACKGROUND

Desflurane's short emergence time supports fast track anaesthesia. Data on the rate of upper airway complications and emergence time when desflurane is used with laryngeal mask airway (LMA) are controversial and limited.

OBJECTIVES

To compare recovery time variables and the rates of upper airway adverse events in patients with an LMA undergoing general surgery with desflurane, sevoflurane, isoflurane or propofol anaesthesia.

DESIGN

A systematic review and meta-analysis of randomised controlled trials (RCTs).

DATA SOURCES

A systematic search for eligible RCTs in Embase (Elsevier) and in PubMed (National Library of Medicine) databases up to September 2013.

ELIGIBILITY CRITERIA

RCTs investigating the rates of cough overall, cough at emergence, laryngospasm, time to eye opening, time to removal of the LMA, time to respond to command and time to state date of birth in patients with an LMA, during emergence from desflurane, sevoflurane, isoflurane or propofol anaesthesia.

RESULTS

Thirteen RCTs were included and analysed. We found a strong interstudy variability. There was no difference in the rates of upper airway events between desflurane and sevoflurane or between desflurane and a control group consisting of all the other anaesthetics combined. Comparing desflurane (n = 284) with all other anaesthetic groups (n = 313), the risk ratio [95% confidence interval (95% CI)] was 1.12 (0.63 to 2.02, P = 0.70). Cough at emergence was only measured in patients receiving desflurane (n = 148) and sevoflurane (n = 146): the risk ratio (95% CI) was 1.49 (0.55 to 4.02, P = 0.43). Laryngospasm was rare and there was no significant difference in its incidence when desflurane (n = 262) was compared with all other anaesthetics combined (n = 289; risk ratio 1.03; 95% CI 0.33 to 3.20, P = 0.96). The times of all emergence variables were significantly faster in the desflurane group than in all other groups.

CONCLUSION

When using an LMA, upper airway adverse reactions in association with desflurane anaesthesia were no different from those noted with sevoflurane, isoflurane or propofol anaesthesia. Emergence from general anaesthesia with desflurane is significantly faster than all the other anaesthetics. Due to interstudy variations and the small size of the trials, further large-scale, multicentre studies are required to confirm or refute the results of this meta-analysis.

Brief review: theory and practice of minimal fresh gas flow anesthesia

PURPOSE

The aim of this brief review is to provide an update on the theory regarding minimal fresh gas flow techniques for inhaled general anesthesia. The article also includes an update and discussion of the practical aspects associated with minimal-flow anesthesia, including the advantages, potential limitations, and safety considerations of this important anesthetic technique.

PRINCIPAL FINDINGS

Reducing the fresh gas flow to < 1 L·min(-1) during maintenance of anesthesia is associated with several benefits. Enhanced preservation of temperature and humidity, cost savings through more efficient utilization of inhaled anesthetics, and environmental considerations are three key reasons to implement minimal-flow and closed-circuit anesthesia, although potential risks are hypoxic gas mixtures and inadequate depth of anesthesia. The basic elements of the related pharmacology need to be considered, especially pharmacokinetics of the inhaled anesthetics. The third-generation inhaled anesthetics, sevoflurane and desflurane, have low blood and low tissue solubility, which facilitates rapid equilibration between the alveolar and effect site (brain) concentrations and makes them ideally suited for low-flow techniques. The use of modern anesthetic machines designed for minimal-flow techniques, leak-free circle systems, highly efficient CO(2) absorbers, and the common practice of utilizing on-line real-time multi-gas monitor, including essential alarm systems, allow for safe and cost-effective minimal-flow techniques during maintenance of anesthesia. The introduction of new anesthetic machines with built-in closed-loop algorithms for the automatic control of inspired oxygen and end-tidal anesthetic concentration will further enhance the feasibility of minimal-flow techniques.

CONCLUSIONS

With our modern anesthesia machines, reducing the fresh gas flow of oxygen to 0.3-0.5 L·min(-1) and using third-generation inhaled anesthetics provide a reassuringly safe anesthetic technique. This environmentally friendly practice can easily be implemented for elective anesthesia; furthermore, it will facilitate cost savings and improve temperature homeostasis.

Desflurane: a clinical update of a third-generation inhaled anaesthetic

Available volatile anaesthetics are safe and efficacious; however, their varying pharmacology provides small but potentially clinically important differences. Desflurane is one of the third-generation inhaled anaesthetics. It is the halogenated inhaled anaesthetic with the lowest blood and tissue solubilities, which promotes its rapid equilibration and its rapid elimination following cessation of administration at the end of anaesthesia. The low fat solubility of desflurane provides pharmacological benefits, especially in overweight patients and in longer procedures by reducing slow compartment accumulation. A decade of clinical use has provided evidence for desflurane's safe and efficacious use as a general anaesthetic. Its benefits include rapid and predictable emergence, and early recovery. In addition, the use of desflurane promotes early and predictable extubation, and the ability to rapidly transfer patients from the operating theatre to the recovery area, which has a positive impact on patient turnover. Desflurane also increases the likelihood of patients, including obese patients, recovering their protective airway reflexes and awakening to a degree sufficient to minimise the stay in the high dependency recovery area. The potential impact of the rapid early recovery from desflurane anaesthesia on intermediate and late recovery and resumption of activities of daily living requires further study.

Knee arthroscopy routines and practice

PURPOSE

Knee arthroscopy is one of most commonly performed day-case orthopaedic procedures, thus consuming huge medical resources. The aim of the present questionnaire survey was to study knee arthroscopy routines and practice.

METHODS

An electronic web-based survey including questions around pre-, per- and postoperative routines for elective knee arthroscopy was send to all orthopaedic units associated to the Swedish Arthroscopic Society (n = 60).

RESULTS

Responses covering 37 centres out of 60 (response rate 62%) were returned. Preoperative radiograph routines varied considerable between centres; conventional radiograph varied between 5 and 100% and preoperative MRI between 5 and 80% of patients. General anaesthesia was the preferred intra-operative technique used in all centres (median 79% of patients), local anaesthesia with or without light sedation was used in all 28 out of the 37 centres responding (median 10% of cases) and spinal anaesthesia was used in 15 centres (median 5% of cases). Intra-articular local anaesthesia was provided in all but one of centres. Perioperative administration of oral NSAIDs was common (31 out 37), 6 centres (all teaching hospitals) did not routinely give pre- or postoperative NSAID. Analgesic prescription was provided on a regular base in 18 (49%) of centres; an NSAID being the most commonly prescribed. All but one centre provided written information and instruction at discharge. Referral to physiotherapy, prescribed sick leave and scheduled follow-up in the outpatient clinic diverged considerably.

CONCLUSION

Routines and practice associated to elective knee arthroscopy differed; however, no clear differences in practice were seen between teaching centres, general or local hospitals apart from a lower usage of NSAID for perioperative analgesia. There is an obvious room for further standardisation in the routine handling of patients undergoing elective arthroscopy of the knee.

Early recovery, cognitive function and costs of a desflurane inhalational vs. a total intravenous anaesthesia regimen in long-term surgery

BACKGROUND

The purpose of the study was to compare time of recovery, return of cognitive function, post-anaesthetic care unit (PACU) stay and costs of a propofol/remifentanil (TIVA) with a desflurane/fentanyl-based anaesthesia (desflurane group) in surgical procedures lasting more than 150 min.

METHODS

Forty-nine patients undergoing elective abdominal prostatectomy were allocated randomly to receive bispectal index (BIS)-controlled desflurane/fentanyl (n=24) or propofol/remifentanil (n=25). Awakening, clinical recovery, direct drug acquisition and post-operative pain treatment were documented. Cognitive skills were tested using the Mini-Mental Status (MMST) test.

RESULTS

Extubation was significantly faster with desflurane (6.9+/-3.5 min) than with TIVA (11.2+/-4.0 min) as well as times for stating name and date of birth (desflurane: 6.1+/-3.9 and 6.6+/-4.0 min; TIVA: 12.4+/-11.5 min and 13.4+/-11.3 min). There were no significant differences in PACU discharge times or MMS scores between the groups. Significantly more patients suffered post-operative nausea and vomiting (PONV) in the desflurane (33% vs. 0%) than the TIVA group. Overall costs were significantly higher in the TIVA (58.8+/-11.6 euro) than in the desflurane group (35.0+/-5.7 euro).

CONCLUSION

Patients undergoing prolonged surgical procedures showed a faster early recovery after desflurane/fentanyl than using TIVA, whereas stay in the PACU and recovery of cognitive function were similar in both groups. Costs of a TIVA regimen were significantly higher than using a desflurane-based anaesthesia technique.

Meta-analysis of trials comparing postoperative recovery after anesthesia with sevoflurane or desflurane

PURPOSE

Results of published, randomized controlled trials comparing sevoflurane and desflurane were pooled to measure differences in times until patients obeyed commands, were extubated, were oriented, were discharged from the postanesthesia care unit (PACU), and were ready to be discharged to home, as well as the occurrence of postoperative nausea and vomiting (PONV).

METHODS

We reviewed all randomized clinical trials in MEDLINE through December 18, 2003, with a title or abstract containing the words sevoflurane and desflurane. Two reviewers independently extracted study data from papers that met inclusion criteria. Endpoints were pooled using random-effects meta-analysis.

RESULTS

Twenty-two reports of 25 studies (3 reports each described 2 studies) met our inclusion criteria. A total of 746 patients received sevoflurane, and 752 received desflurane. Patients receiving desflurane recovered 1-2 minutes quicker in the operating room than patients receiving sevoflurane. They obeyed commands 1.7 minutes sooner (p < 0.001; 95% confidence interval [CI], 0.7-2.7 minutes), were extubated 1.3 minutes sooner (p = 0.003; 95% CI, 0.4-2.2 minutes), and were oriented 1.8 minutes sooner (p < 0.001; 95% CI, 0.7-2.9 minutes). No significant differences were detected in the phase I or II PACU recovery times or in the rate of PONV.

CONCLUSION

Meta-analysis of studies in which the duration of anesthesia was up to 3.1 hours indicated that patients receiving either desflurane or sevoflurane did not have significant differences in PACU time or PONV frequency. Patients receiving desflurane followed commands, were extubated, and were oriented 1.0-1.2 minutes earlier than patients receiving sevoflurane.

Sevoflurane: an ideal agent for adult day-case anesthesia?

Sevoflurane has several properties which make it potentially useful as a day case anaesthetic. Following induction of anaesthesia with propofol, awakening from sevoflurane is faster compared to isoflurane, faster or similar compared to propofol and comparable (in the majority of studies) to desflurane. Subsequent recovery and discharge is generally similar following all agents. Sevoflurane may also be used to induce anaesthesia, which is generally well-received and causes less hypotension and apnoea compared to propofol. When used as a maintenance anaesthetic, the incidence of postoperative nausea and vomiting after sevoflurane is comparable to other inhaled anaesthetics, but this complication appears more common after inhaled inductions. The tolerability and low solubility of sevoflurane facilitate titration of anaesthesia and may reduce the need for opioid analgesia, which in turn may limit the occurrence of nausea and vomiting.