Desflurane Consumption Research Articles

A Comparative Study of Fixed-Dose Dexmedetomidine and Propofol Infusions on Intraoperative Desflurane Consumption During Bispectral Index-Guided Laparoscopic Surgeries: A Randomized Controlled Study.

Background Desflurane is an excellent but expensive volatile anesthetic agent. Dexmedetomidine and propofol may decrease intraoperative desflurane consumption. This study aimed to compare the desflurane-sparing effect of dexmedetomidine and propofol in patients undergoing laparoscopic surgeries under bispectral index (BIS)-guided general anesthesia (GA). Methods Sixty-two adult patients, ASA (American Society of Anesthesiologists) physical status I or II, of either sex, aged between 18 and 60 years, were randomly allocated into group D or group P. Only group D patients received an intravenous (IV) bolus of dexmedetomidine (1 mcg/kg) over 15 minutes before induction. In both groups, GA was induced following the standard protocol with propofol infusion (0.5 mg/kg/min) until the BIS value dropped below 60. For maintenance, group D and group P patients received IV dexmedetomidine infusion (0.5 mcg/kg/h) and propofol infusion (50 mcg/kg/min), respectively. In both groups, desflurane dial concentration was adjusted between 3 and 8% to maintain the BIS within the range of 45-55. An hourly bolus of IV fentanyl (0.5 mcg/kg) and a half-hourly bolus of IV vecuronium (0.02 mg/kg) were administered. The total amount of desflurane consumed, duration of pneumoperitoneum, extra aliquots of propofol used during maintenance, number of boluses of IV atropine, fentanyl, and esmolol, time to attain Ramsay Sedation Score of 2 after extubation, time to first postoperative analgesic request at Numerical Rating Scale (NRS) score ≥ 4, time to reach a Modified Aldrete Score of ≥9, and incidence of any side effects were recorded. All the data were analyzed and compared using appropriate statistical tests, and a p-value of <0.05 was considered significant. Results The final data analysis was performed on 60 patients. The mean desflurane consumption was clinically higher in group P patients than in group D, but the difference was statistically insignificant (p-value > 0.05). The mean induction dose of propofol was significantly less in group D than in group P (p-value < 0.05). After extubation, the difference in time to the first analgesic request (NRS ≥ 4) between the groups was statistically significant (p-value < 0.05). Group D patients had a residual intraoperative analgesic effect. Conclusion The effects of dexmedetomidine and propofol infusions on desflurane consumption in laparoscopic surgeries are comparable, with minimal effects on intraoperative hemodynamics and postoperative recovery profiles.

Predicting the climate impact of healthcare facilities using gradient boosting machines

Health care accounts for 9–10% of greenhouse gas (GHG) emissions in the United States. Strategies for monitoring these emissions at the hospital level are needed to decarbonize the sector. However, data collection to estimate emissions is challenging. We explored the potential of gradient boosting machines (GBM) to impute missing data on resource consumption in the 2020 survey of a consortium of 283 hospitals participating in Practice Greenhealth. GBM imputed missing values for selected variables in order to predict electricity use (R2 = 0.82) and beef consumption (R2 = 0.82) and anesthetic gas desflurane use (R2 = 0.51), using administrative and financial data readily available for most hospitals. After imputing missing consumption data, estimated GHG emissions associated with these three examples totaled over 3 million metric tons of CO2 equivalent emissions (MTCO2e). Specifically, electricity consumption had the largest total carbon footprint (2.4 MTCO2e), followed by beef (0.6 million MTCO2e) and desflurane consumption (0.03 million MTCO2e) across the 283 hospitals. The approach should be applicable to other sources of hospital GHGs in order to estimate total emissions of individual hospitals and to refine survey questions to help develop better intervention strategies.

Effect of combined intraoperative use of the Nociception Level (NOL) and bispectral (BIS) indexes on desflurane administration

BackgroundCurrently, nociception monitors are not part of standard anaesthesia care. We investigated whether combined intraoperative nociception (NOL index) and anaesthesia (BIS index) monitoring during general anaesthesia would reduce anaesthetics consumption and enhance intraoperative safety and postoperative recovery when compared to standard of care monitoring (SOC). MethodsIn this randomised study, we included 60 patients undergoing colonic surgery under desflurane/remifentanil anaesthesia and epidural analgesia. Patients received either standard monitoring or combined BIS + NOL index monitoring. In the monitored group, remifentanil infusion was titrated to achieve a NOL index below 20. Desflurane was adjusted to BIS values (45–55). In the SOC group, remifentanil and desflurane were titrated on vital signs and MAC. The primary outcome was intraoperative desflurane consumption. ResultsFifty-five patients were analysed. Desflurane administration was reduced in the monitored group from 0.25 ± 0.05 to 0.20 ± 0.06 mL kg−1 h−1 (p < 0.001). The cumulative time with a BIS under 40 was significantly higher in the SOC group with a median time of 12.6 min (95% CI: 0.6–80.0) versus 2.0 min (95% CI: 0.3–5.83) (p = 0.023). Time for extubation was significantly shorter in the monitored group: 4.4 min (95% CI: 2.4–4.9) versus 6.28 min (95% IC: 5.0–8.2) (p = 0.003). We observed no differences in remifentanil or phenylephrine requirements during anaesthesia or in postoperative outcome measures, such as postoperative pain, opioid consumption, neurocognitive recovery. ConclusionCombined intraoperative monitoring of anaesthesia and nociception during colonic surgery resulted in less desflurane consumption and quicker extubation time compared to standard clinical care monitoring.

Analgesic effects of ultrasound guided paravertebral block versus transversus abdominis plane block in hepatic patients undergoing laparoscopic cholecystectomy

Background: Several analgesic modalities after laparoscopic cholecystectomy were used in hepatic patients but with various complications. Bilateral ultrasound-guided transverse abdominis plane block (TAP) or thoracic paravertebral block (PVB) may provide safer techniques than others. The aim of this study is to delineate the more efficient and safer technique either TAP or PVB in hepatic patients. Methods: The research was conducted on sixty adult hepatic patients, ASA II or III, Child A or B, undergoing laparoscopic cholecystectomy. Patients were allocated randomly into one of two equal groups, to attain bilateral ultrasound guided either PVB (Group P) or TAP block (Group T). Group P showed significant postoperative lower pain scores using visual analogue score at 2, 4, 6 and 24 h (P &lt; 0.01) and less intraoperative desflurane and fentanyl consumption (P &lt; 0.001) versus group T. In addition, group P exhibited less total postoperative pethidine requirement (23.3±25.4 mg vs. 38.3±21.5 mg, P = 0.017), fewer number of patients asked for postoperative analgesia (46.7% vs. 76.7%, P value = 0.017), longer duration to first analgesic demand (20.5±5.1 h vs. 15.1±8.4 h, P = 0.021), and compared to group T respectively. Regarding liver functions and haemodynamics, both groups were comparable at different intervals.

Desflurane consumption with automated vapour control systems in two different anaesthesia machines. A randomized controlled study.

In general anaesthesia practice a fresh gas flow (FGF) of ≥0.5L/min is usually applied. Automated gas delivery devices are developed to reduce volatile anaesthetic consumption by limiting gas flow. This study aimed to compare desflurane consumption between automated gas control devices compared to conventional low flow anaesthesia in the Flow-I and Aisys anaesthesia machines, and to compare desflurane consumption between the two automated gas delivery devices. We hypothesised that desflurane consumption would be lower with automated gas delivery compared to conventional low flow anaesthesia, and that desflurane consumption could differ between the different gas delivery devices. We allocated 160 patients undergoing robot-assisted laparoscopic surgery into four groups, Flow-I with automated gas control, Flow-i with conventional low-flow(1 L/min), Aisys with end tidal gas control and Aisys with conventional low flow. Patients were maintained at minimum alveolar concentration (MAC) 0.7-0.8. Desflurane consumption was recorded after 9, 30 and 60minutes of anaesthesia. After 60minutes, compared to conventional low flow anaesthesia, automated gas delivery systems reduced desflurane consumption from 25.8 to 15.2mL for the Aisys machine (P<.001) and from 22.1 to 16.8mL for the Flow-I (P<.001). Time to MAC 0.7 and stable FGF was shorter with Aisys endtidal control compared to Flow-I automated gas control. Under clinical conditions, we found a reduction in desflurane consumption when using automated gas delivery devices compared to conventional low flow anaesthesia. Both devices were reliable in use.

Comparative study of desflurane requirement and recovery characteristics in entropy guided general anaesthesia with or without dexmedetomidine infusion

Background: Newer anaesthetics such as desflurane have smaller blood-gas partition coefficient than older ones like halothane. Desflurane is preferred because it leads to faster onset of anaesthesia and faster emergence from anaesthesia. However, desflurane is considered to be more expensive than other volatile anaesthetics. Highly selective alpha two adrenoceptor agonists like Dexmedetomidine reduce anaesthetic requirements. Hence this study was designed to compare the effect of Dexmedetomidine infusion on desflurane consumption and recovery characteristics under entropy guided general anaesthesia. Materials and Methods: Fifty patients aged between 18-55 years belonging to ASA I and II scheduled for elective surgeries under general anaesthesia were randomly divided into two groups. Group D patients received a loading dose of inj Dexmedetomidine 1 µg/ kg, over 10 minutes before the induction of anaesthesia, and 0.5 µg/ kg/ hour infusion following induction of anaesthesia till the end of surgery. Group P patients received similar volumes of normal saline as bolus before the induction and maintenance infusion till the end of the surgery. Desflurane concentration was adjusted to maintain response entropy values between 40 to 60 and based on clinical variables like heart rate (HR), and mean arterial pressure (MAP). Muscle relaxation was guided by TOF count. HR, NIBP, MAP, SPO2, ENTROPY values were recorded. The total desflurane consumption was recorded from Anaesthesia gas module of GE Datex-Ohmeda S 5 Advance system. At end of surgery, desflurane was discontinued and patient extubated after adequate recovery and when TOF ratio was more than 0.9. Time to eye opening, extubation, response to verbal commands were recorded. Results: The mean consumption of desflurane at the end of one hour was significantly less in group D with p&lt;0.001 (Group P 21.04±6.33 ml/hr and Group D 14.44±1.83 ml/hr). Eye opening time was significantly less in group D with p&lt;0.001(Group P 297.60± 89.97sec and Group D 169.80±22.48 sec). Time for response to verbal commands was significantly less in group D with p&lt;0.001 (Group P 423.60±113.02 sec and Group D 269.80±45.29 sec) Conclusion: Intraoperative Dexmedetomidine infusion reduces desflurane consumption, hastens recovery from desflurane during entropy guided general anaesthesia.

Implementation of magnesium sulphate as an adjunct to multimodal analgesic approach for perioperative pain control in lumbar laminectomy surgery: A randomized placebo-controlled clinical trial

ObjectiveTo investigate the effect of systemic intraoperative administration of magnesium sulphate when used in the context of a multimodal pain management plan on analgesics consumption and pain scores, and perioperative outcomes after lumbar laminectomy surgery. MethodsSeventy-four patients undergoing lumbar laminectomy were enrolled in this randomized, double-blind, placebo-controlled trial. Participants were randomly allocated to receive magnesium (20 mg/kg iv given as bolus before anesthesia induction followed by 20 mg/kg/h civ until surgery completion) or saline. Hemodynamic variables and desflurane consumption were noted at predefined time-intervals intraoperatively. Primary outcome was postoperative cumulative analgesic consumption over 24 h, while pain intensity (assessed by Visual Analogue Scale [VAS] at 1, 2, 4, 6 and 24 h), intraoperative hemodynamics and opioid requirements, recovery profile, time to first analgesic request, and adverse effects constituted secondary end-points. ResultsDemographics, surgery duration, desflurane requirements, and recovery profile were comparable between groups. Magnesium attenuated hemodynamic response during incision and emergence from anesthesia. Postoperative analgesics consumption in morphine iv equivalents (mean difference −9.24 [95 %CI −13.31, −5.17] mg; p = 0.001) and VAS scores at all-time points of assessment were lower in magnesium group; this effect peaked at 4 h (mean difference −2.15 [95 %CI −3.21,−1.09; p = 0.001]. Magnesium reduced intraoperative remifentanil consumption and prolonged the time-interval to first rescue analgesia (p < 0.01). No notable adverse effects were recorded. ConclusionIt occurs that magnesium infusion during lumbar laminectomy surgery potentiates perioperative analgesia and reduces analgesic requirements up to 24 h postoperatively. No profound adverse effect on either intraoperative hemodynamics or any other clinically relevant endpoints becomes evident.

Are high fresh gas flow rates necessary during the wash-in period in low-flow anesthesia?

In low-flow anesthesia (LFA), there is a wash-in period in which usually high fresh gas flow (FGF) rates are used to achieve the required initial concentration of anesthetic agent in the alveoli. The aim of this study was to compare the efficiency, safety and the consumption of desflurane in LFA using constant FGF (1 L/min) and conventional LFA using high FGF (4 L/min) during the wash-in period. Eighty patients, who were scheduled for elective surgery under general anesthesia with endotracheal intubation, were enrolled in the study. Wash-in was accomplished with 1 L/min FGF (50% O2, 50% air) and 18% desflurane in group 1; and by 4 L/min FGF (50% O2, 50% air) and 6% desflurane in group 2. Throughout the surgery, the vaporizer was adjusted to maintain 0.6 to 0.8 minimum alveolar concentration (MAC). The time required to reach 0.7 MAC was shorter in group 1 (160 seconds [135-181] vs 288 seconds [240-500], P < .001). In 6 patients in group 1 and 13 in group 2, vaporizer settings were adjusted to maintain 0.6 to 0.8 MAC (P = .048). Desflurane consumption in the first hour and total desflurane consumption were higher in group 2 (P < .001 and P = .012, respectively). The efficiency of anesthesia in both the first hour and in total was higher in group 1 (P < .001). It is safe, more efficient, and economical to use 1 L/min FGF during the wash-in period in LFA.

Consumption and Intraoperative Controllability of Desflurane-A Randomized Trial Comparing Manually-Assisted (Perseus® A 500- Dräger) and Automated Control (Aisys® Cs2-GE) of End-Tidal Concentrations

Purpose : As compared to conventional manually-assisted administration, the automated-control of end-tidal inhalation anaesthetic concentration (EtControl® Aisys® Cs2 - GE) allows for a reduction of halogenated gas consumption and an improvement of the target end-tidal fraction (Fet) controllability. However, recent real time decision support software may help anaesthesiologists to optimize manually-assisted halogenated agent delivery (VaporView®, Perseus A500® - Drager). The aim of this study was to compare these two delivery methods. Methods: This was a prospective randomized study comparing the consumption and controllability of Desflurane (Des) between the Vaporview® and Etcontrol® modes of administration in daily clinical practice conditions with a hypothesis of non-inferiority. The Vaporview® mode followed a protocol similar to the Etcontrol® mode for the wash in and wash out periods, and followed the Vaporview® curve to adjust the delivered Fraction (Fd) during the maintenance of the end-tidal fraction (Fe) at 0.5 l.min-1 fresh gas flow. Consumptions were measured by micrometric weighing of the vaporizer. Results: 58 patients were randomized. The Desflurane consumption in the Perseus Vaporview` group was 13.71 ml.hr-1 (95% CI: 13.02-14.41) versus 13.27 ml.hr-1 (95% CI: 12.30-14.24) in the reference Aisys Etcontrol® group, satisfying statistical criteria for non-inferiority. There were no significant differences either in time to reach MAC 1, or in the number of Fd/Fe adjustments per hour. Conclusions: Within clinical daily practice conditions, consumption of Desflurane with manually-assisted delivery (Drager Perseus Vaporview®) was not statistically different from automated control delivery (General Electrics Aisys EtControl®), with the same Fe kinetic profiles and ventilator adjustment requirements.

Comparative Study of Automated End Tidal Control Versus Manual Fresh Gas Flow Adjustment with Respect to Gas Usage and Delivery during Low Flow Anesthesia

Background: During low-flow manually-controlled anesthesia (MCA) the anesthetist keeps adjusting end-tidal oxygen (EtO2) and anesthetic concentrations (EtAA) constantly to ensure adequate and safe anesthesia. This study was performed to compare End Tidal Control and Manual Control of Fresh gas flow during low flow anesthesia. Methods: Study was conducted on 84 ASA I and II patients 18-65 years age, of either sex, requiring general anesthesia for more than 2 hours. In MCA group (n = 42) target end-tidal desflurane (4%) and EtO2 concentrations (≥ 35%) were manually controlled by the anesthetist. In EtCA group (n = 42), same anesthetic machine with additional end-tidal control feature was used to reach same targets. Results: The median desflurane consumption was 15.71 ml and 16.71 ml in ETCA and MCA respectively (p value =0.002) after one hour and 28.71ml and 32.98 ml in ETCA and MCA respectively (p value <0.001 ) after two hours. In ETCA group, median number of adjustments was 3.83 after one hour and 7 after two hours (p – value <0.001). Cost of anesthetic agent consumed after one hour in ETCA group was Rs 562.57 and MCA group was Rs 598.37 (p value<0.002) . After two hours, cost of anesthetic agent consumed in ETCA group was Rs 1008.367 and in MCA group was Rs 1173.729 (p value <0.001). Conclusion: Automatic implementation of low flow anesthesia using end tidal control is a good system for conserving the consumption of gases and reducing the number of adjustments needed to maintain depth of anesthesia.

The role of dexmedetomidine infusion on intraoperative desflurane and fentanyl requirement in spine surgery

Introduction Dexmedetomidine is a potent selective agonist of α2 adrenoceptor having sedative, amnestic, sympatholytic, and pain-relieving properties without producing significant respiratory depression and promotes hemodynamic stability when used as an adjuvant during general anesthesia. Aim The objective of this study was to evaluate the effect of dexmedetomidine infusion on desflurane consumption, intraoperative fentanyl requirement, and hemodynamic changes. Patients and methods Sixty patients of American Society of Anesthesiologists I and II enlisted for elective spine surgery were randomly classified into two groups: group D dexmedetomidine group received preoperative intravenous dexmedetomidine 0.5 μg/kg over 10 min followed by 0.25 μg/kg/h (1 ml, 100 μg diluted with normal saline in 20 ml syringe) intraoperative infusion till the end of surgery and group P, the placebo group received a similar volume of normal saline. Desflurane consumption and intraoperative fentanyl requirement were recorded as well as intraoperative hemodynamic changes. Results Desflurane consumption and intraoperative fentanyl requirement were significantly lower in group D (P&lt;0.001) as well as there was a significant decrease in heart rate and mean arterial blood pressure (P&lt;0.05) in D group Conclusion Dexmedetomidine infusion resulted in significant reduction of desflurane consumption and intraoperative fentanyl requirement with significant decrease in heart rate and mean arterial blood pressure.

Effect of entropy-guided low-flow desflurane anaesthesia on laryngeal mask airway removal time in children undergoing elective ophthalmic surgery - A prospective, randomised, comparative study.

Background and Aims:In children, entropy-guided titration of isoflurane and sevoflurane leads to faster recovery after anaesthesia. However, role of entropy in recovery following desflurane anaesthesia is not known. Hence, we compared laryngeal mask airway (LMA) removal time and desflurane consumption with entropy and minimal alveolar concentration–guided titration in children given low-flow desflurane anaesthesia.Methods:After ethics committee approval and parental consent, 80 American Society of Anesthesiologists grade I–II children, age 2–14 years, undergoing elective ophthalmic surgery were randomised into entropy and minimal alveolar concentration–guided groups. After LMA insertion, anaesthesia was maintained using oxygen, air (FiO2 0.5) and desflurane using low fresh gas flow of 0.75 L/min. In the entropy-guided group, desflurane was titrated to maintain state entropy between 40 and 60. In the minimal alveolar concentration–guided group, desflurane was titrated to maintain a minimal alveolar concentration between 1 and 1.3. We recorded LMA removal time (from switching off desflurane at the end of surgery till removal of LMA), haemodynamic parameters, uptake and consumption of desflurane between the groups.Results:LMA removal time was significantly decreased in the entropy-guided group in comparison to the minimal alveolar concentration–guided group (4.34 ± 2.03 vs 8.8 ± 2.33 min) (P < 0.0001). Consumption of desflurane was significantly less in the entropy-guided group compared with the minimal alveolar concentration–guided group (18.7 ± 5.07 vs 25.3 ± 8.11 mL) (P < 0.0001).Conclusion:Entropy-guided low-flow desflurane anaesthesia is associated with faster LMA removal and reduced consumption of desflurane in children undergoing ophthalmic surgery.

Low-flow anaesthesia with a fixed fresh gas flow rate.

During the wash-in period in low flow anaesthesia (LFA), high fresh gas flow is used to achieve the desired agent concentration. In this study, we aimed to evaluate the safety of fixed 1L/min fresh gas flow desflurane anaesthesia in both the wash-in and maintenance periods in patients including the obese ones. 104 patients undergoing surgery under general anaesthesia were included. After endotracheal intubation, fresh gas flow was reduced to 1L/min and the desflurane vaporizer was set at 18%. The time from opening the vaporizer to end-tidal desflurane concentration reaching 0.7 MAC was recorded (MAC 0.7 time). Throughout the surgery, hemodynamic variables, FIO2, MAC and BIS values were observed. MAC 0.7 time, BIS and MAC values at the start of surgery, number of adjustments in vaporizer settings, desflurane consumption were recorded. The average MAC 0.7 time was 2.9 ± 0.5min. MAC and BIS values at the start of the surgery were 0.7 (0.6-0.8) and 39 ± 8.5 respectively. No individual patient had a BIS value above 60 throughout the surgery. Hemodynamic variables were stable and FIO2 did not fall below 30% in any patient. The number of adjustments in vaporizer settings was 56. Average desflurane consumption was 0.33 ± 0.05mL/min. We demonstrated that LFA without use of initial high fresh gas flow during the wash-in period is an effective, safe and economic method which is easy to perform.

Effect of dexmedetomidine infusion on desflurane consumption and hemodynamics during BIS guided laparoscopic cholecystectomy: A randomized controlled pilot study

BackgroundDexmedetomidine is an α-2 adrenoceptor agonist with sedative and analgesic properties. Desflurane is the most rapidly washed volatile anesthetic agent allowing rapid recovery with minimal metabolism. Having a MAC of 6 vol % made it important to look for an adjuvant that would minimize its consumption. This study was undertaken to analyze desflurane consumption when combined with dexmedetomidine infusion guided by bispectral index as well as calculating intraoperative fentanyl requirements and recording hemodynamic changes associated with this technique.MethodsForty adult patients ASA class I and II of either sex scheduled for elective laparoscopic cholecystectomy were included in this study. Patients were randomized to one of two groups: Group ‘D’ (Dexmedetomidine group) receiving 1μg/kg over 10 minutes followed by an infusion at 0.5 μg/kg/hr and Group ‘P’ (Placebo group) who received same volumes of normal saline. Desflurane was started at a concentration of 6% then adjusted to keep BIS level within the range of 40-50. Desflurane consumption, fentanyl requirements as well as hemodynamics were either calculated or recorded.ResultsDesflurane consumption and total fentanyl usage were significantly lower in group D versus group P with P value < 0.001. As regards hemodynamics, group D showed statistically significant lower readings versus the preoperative levels (P<0.05) as well as versus group P at the same timings (P<0.05) for most of the readings.ConclusionsContinuous intravenous administration of dexmedetomidine resulted in significant reduction of desflurane consumption and intraoperative fentanyl requirements with attenuation of hemodynamic response to intubation, pneumoperitoneum and extubation.

Postoperative pain scores and opioid consumption in opioid-dependent patients with cancer after intraoperative remifentanil analgesia: A prospective case-controlled study.

Opioid dependency is becoming increasingly common among surgical patients with cancer, and can lead to inadequate pain relief during the initial postoperative period. No guidelines are currently available for the management of perioperative and postoperative morphine administration in these patients. As a first approach, the authors assessed the opioid requirements of these patients during the early postoperative period. A group of 35 consecutive surgical patients with cancer on opioid therapy (opioid-dependent group) for cancer pain were compared to a matched group of 44 surgical opioid-naive patients (control group). All patients underwent major head and neck or abdominal surgery. The following parameters were recorded and compared: preoperative and postoperative morphine consumption, patient-controlled analgesia records and Visual Analog Scale scores, intraoperative remifentanil and desflurane consumption, Bispectral Index monitoring values, heart rate, and blood pressure. Remifentanil requirements were significantly higher (1.4-fold) in the opioid-dependent group compared to the control group (p < 0.05). On postoperative day 1, morphine requirements were significantly higher in the opioid-dependent group (2.3-fold) compared to the control group (p < 0.05). Baseline heart rate was significantly higher in the opioid-dependent group and this difference remained significant during surgery, no significant difference in blood pressure was observed between the two groups. This study shows a 40 percent increase of intraoperative remifentanil requirements in opioid-dependent patients during cancer surgery. Morphine requirements during the postoperative period were increased by up to 140 percent.

A low dose of droperidol decreases the desflurane concentration needed during breast cancer surgery: a randomized double-blinded study.

BackgroundDroperidol (DHB) reportedly reduces the dose of propofol needed to achieve hypnosis when anesthesia is induced and decreases the bispectral index (BIS) in propofol-sedated patients during spinal anesthesia. We reported previously that supplemental DHB decreased the BIS after the administration of sevoflurane and remifentanil. This study investigated the effect of DHB on desflurane (DES) consumption in a clinical setting.MethodsWe conducted a prospective, randomized double-blinded study of 35 women with American Society of Anesthesiologist physical status I or II who underwent a mastectomy. Either DHB (20 µg/kg) or a saline placebo was administered to patients 30 min after the induction of anesthesia. A blinded anesthesiologist maintained a BIS value of 50 during anesthesia by modulating inhaled DES concentrations that changed 0.5% at 2.5 min intervals and maintained analgesia via the constant administration of remifentanil by referring to vital signs. The primary endpoint was the effect of DHB on DES consumption. The secondary endpoints included blood circulatory parameters, the time from the end of surgery to extubation, and discharge time between the groups.ResultsThe characteristics of the patients did not differ between the groups. The DHB group used a mean of 27.2 ± 6.0 ml of DES compared with 41.4 ± 9.5 ml by the placebo group (P < 0.05).ConclusionsA small dose of DHB reduced the DES concentration needed to maintain a BIS of 50. Our results show that DHB reduced the consumption of DES without adverse effects.

Pharmacoeconomics of desflurane based minimal flow anesthesia for different durations of surgery

Background: Desflurane is relatively newer volatile anesthetic in clinical practice with many advantages. Unfortunately, it is comparatively costlier. The present observational study is aimed to evaluate the consumption pattern and cost of Desflurane based minimal flow anesthesia with regards to different durations of anesthesia. Methods: Twenty adults of American Society of Anesthesiologists’ class I and II of either sex were enrolled for the study with informed consent during November 2015 to January 2016. Anesthesia was performed using Intermed Penlon sigma Alfa Desflurane vaporizer and Penlon Prima SP2 workstation. Age and opioid compensated minimum alveolar concentration was fixed for each patient and was monitored using Penlon SP M8 monitor and its attached anesthesia gas monitoring system. Bispectral index was used in affordable patients to monitor depth of anesthesia. Data of Desflurane consumption was collected from the digital numerical display on the vaporizer screen. Statistical analysis was done using INSTAT software and cost was calculated from maximum retail price. Results: Data from 20 patients consisting 60% male (mean + standard deviation age of 39.8 + 16.9 years and weight of 59.7 + 12.52 kilograms) were analyzed. Gender had no effect on consumption of Desflurane. Older patients (>60 years) consumed less than the younger (p<0.05). Mean Desflurane consumption was highest during first 5 minute (6.2 ml) and followed decreasing trend till 45 minute of anesthesia (p<0.05) followed by a near steady consumption. Cost of Desflurane reduced from Indian Rupees 22/minute for 15 minute anesthesia to Indian Rupees 6/minutes for 3 hours anesthesia. Conclusions: Desflurane consumption and cost do not depend on sex but on age, flow and time. It becomes more cost-effective for relatively longer duration of minimal flow anesthesia.

Accuracy of calculated volatile agent consumption from fresh gas content.

Case-by-case assessment of volatile anesthetic (VA) consumption is necessary to perform agent sparing dosing measures and for billing purposes. The gold standard technique for this purpose is to measure the weight difference of the vaporizer that occurs during VA delivery. Because suitable equipment is rarely available and weighing the vaporizer is only possible in prospectively planned fashion, a calculation method from recorded fresh gas flow (FGF) and VA courses is a viable alternative. The objective was to evaluate the accuracy of VA calculation from fresh gas composition vs. the gold standard of weighing the vaporizer before and after anesthesia. In this prospective laboratory investigation, we compared the formula-based calculations of VA consumption to the measured vaporizer weight differences before and after 10 sevoflurane and 10 desflurane anesthesia. We assessed the average difference and spread of values between the calculated and the measured values. The calculated sevoflurane consumption overestimated the measured values by 3.0 ± 2.9 ml (6.2%). The calculated desflurane consumption overestimated the measured values by 3.5 ± 6.7 ml (5.0%). All pairs of values from both agents were within ± 1.96 standard deviations. The calculated VA consumption for sevoflurane and desflurane are sufficiently accurate to estimate the economic impact of VA delivery during inhalational anesthesia. This method enables the assessment of VA consumption both ways: (1) retrospectively from sufficiently detailed and accurate anesthesia recordings, as well as (2) by using this method in a prospective setting.

Reliability of the volatile agent consumption display in the Draeger Primus™ anesthesia machine.

Knowledge of the consumed amount of volatile anesthetic (VA) expressed in liquid agent is necessary to enable agent sparing dosing measures and for billing purposes. The widespread Draeger Primus™ anesthesia machine displays in its logbook the amount of consumed VA at the end of each anesthesia, but the reliability of this parameter is yet unknown. The objective was to evaluate the precision and reliability of the inbuilt VA consumption display in Draeger Primus™ anesthesia machines as compared with the gold standard of weighing the vaporizer before and after anesthesia. In this prospective laboratory investigation we compared the VA consumption displayed by the Draeger Primus™ anesthesia machine with measured vaporizer weight differences before and after 10 sevoflurane and 10 desflurane anesthesias. We assessed the average difference and spread of values between the predicted (displayed) and measured (control) values for VA consumption. The displayed sevoflurane consumption overestimated the measured values by 4.3 ± 5.4 ml (7.6%). The displayed desflurane consumption underestimated the measured values by -3.5 ± 6.3 ml (6.2%). Nine from 10 sevoflurane pairs of values and all desflurane pairs of values were within ±1.96 SD. The displayed VA consumption calculations for sevoflurane and desflurane in the Draeger Primus™ are sufficiently reliable to estimate the pharmacoeconomic impact of VA delivery during inhalational anesthesia.

Yüksek ve Düşük Akımlı Desfluran Anestezisinin Hemodinami, Derlenme ve Maliyet Açısından Karşılaştırılması

Objective: We are in this study, the high-and low-flow anesthesia, hemodynamics, recovery, and we aimed to compare in terms of cost. Methods: Submucosal resection and septorhinoplasty operation is planned in the study group, ASA I-II, the operation will last for 1–3 hours, between 18–65 years of age, 40 patients were included. Group D low-flow, high-flow group was determined as the Y group. Hemodynamic changes was measured preop. In Group D of the 10th from the current 1 min after L / min (0.5L/dk oxygen, 0,5 L/min air) downloads. Study, FIDES, ETDES, FiO2, FiCO2, ETO2, ETCO2, MAK measurement after intubation, 10, 15, 30, 45, 60, 75 minutes was measured. Group D, high-flow anesthesia is terminated 10 minutes before reanesthetized 6 L/min was started. Results: Intra-operative group D in 15 minutes mean blood pressure was statistically lower. FiO2, Group D in the fresh gas flow 1 L/min or after deduction of up to 35% of the fallen, but never below the 30% critical value. ETDES 30 min, MAK, and FIDES 15 and 30 min in group A to group D also found relatively low. Oxygen and desflurane consumption was significantly lower in group D according to the group H. Desflurane consumption falls by 66%, according to group D than in Group A was lower.Conclusion: We observed that low-flow anesthesia is more cost-effective than high-flow anesthesia and it’s as safe as high-flow anesthesia on hemodynamics and recovery time