Effect of remifentanil on consumption of sevoflurane in entropy monitored general anesthesia

Abstract

BackgroundMonitoring of anesthetic depth is important for successful general anesthesia. It is well known that entropy or BIS monitoring assisted titration of anesthetic drugs decreases their consumption. This study evaluated the effect of remifentanil on consumption of sevoflurane during entropy monitored general anesthesia.MethodsPatients were randomly assigned to two groups. The R group was administered 0.1 µg/kg/min of remifentanil and inhaled sevoflurane, while the S group was administered only inhaled sevoflurane. Anesthesia was maintained using sevoflurane with nitrous oxide, and entropy was monitored. In both groups, the concentration of sevoflurane was adjusted to keep the state entropy (SE) value between 40 and 60. End-tidal sevoflurane concentration (ET), entropy value, systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were measured at 5 minute intervals, during a 25 minute period after intubation, skin suture and the end of surgery.ResultsET was significantly lower in the R group than the S group. There were no significant differences in entropy value between R and S groups.ConclusionsEntropy monitored titration of sevoflurane with remifentanil administration decreased ET with stable hemodynamics.

Preoperative paracetamol infusion reduces sevoflurane consumption during thyroidectomy under general anesthesia with spectral entropy monitoring

“…Sert and his colleagues [36] concluded that the use of low flow sevoflurane anesthesia combined with continuous intraoperative remifentanil infusion during tympanoplasty resulted in a faster early recovery and decreased sevoflurane consumption. Similarly, Kim et al [7] in a study of 40 females undergoing gynecological surgery with entropy monitored general anesthesia, demonstrated that the end-tidal sevoflurane concentration as well as the total volatile gas consumption had been reduced by continuous intraoperative remifentanil infusion. We agree with those authors [7,36] in the context that reducing the consumption of the inhalational anesthetics without compromising both the clinical outcome and the patient satisfaction is highly desirable in order to facilitate earlier recovery from general anesthesia and to minimize the environmental pollution and the economic waste.…”

“…Similarly, Kim et al [7] in a study of 40 females undergoing gynecological surgery with entropy monitored general anesthesia, demonstrated that the end-tidal sevoflurane concentration as well as the total volatile gas consumption had been reduced by continuous intraoperative remifentanil infusion. We agree with those authors [7,36] in the context that reducing the consumption of the inhalational anesthetics without compromising both the clinical outcome and the patient satisfaction is highly desirable in order to facilitate earlier recovery from general anesthesia and to minimize the environmental pollution and the economic waste. In the present study, we used the spectral entropy monitoring to titrate the sevoflurane concentration to the desirable depth of anesthesia.…”

“…Hz and shows the value in the range of 0-100 [6]. State entropy values between ''40-60'' are the recommended surgical level of anesthesia while ''100'' signifies awake state and ''0'' indicates suppression of the cortical neuronal activity [7].…”

Anesthesia for a Patient with Base of Tongue Mass undergoing Transoral Robotic Surgery: A Case Report

“…The anesthesia was maintained with a volatile-based (sevoflurane at 2%) technique to maintain a MAC value of 0.7-1.0 with an intravenous agent (remifentanil TCI at 1-2 ng/ml). In the study of Kim HT et al 18 , on the effect of remifentanil on the consumption of sevoflurane, stated that the administration of a low dose of remifentanil (0.1 μg/kg/min) as a supplement to inhaled anesthetics, will allow for a reduced dose of inhaled anesthetics, compared to when inhaled anesthetics are used alone. In addition, balanced anesthesia with these two agents allows for shorter recovery without postoperative side effects such as postoperative nausea and vomiting.…”

Comparison of Hemodynamics Recovery Profile and Costs of Remifentanil Versus Fentanyl-Based Sevoflurane Anesthesia

“…20 In another trial investigating the effect of remifentanil on sevoflurane consumption by entropy monitoring, remifentanil was used at a dose of 1 μg/kg in the study group; for maintenance, one group was administered 0.1 μg/kg/min remifentanil while the other received 0.002 mL/kg/min saline infusion and the investigators administering saline infusion reported a significantly lower end-tidal sevoflurane value in the remifentanil group. 21 Beers et al compared the cost-effectiveness of remifentanil and fentanyl and used 3µg/kg fentanyl in one group and 0.5 µg/kg remifentanil in the other group for induction, and for the maintenance of anesthesia; the second group was administered 0.2 µg/kg/min of remifentanil as infusion. 22 Sevoflurane consumption was 12 mL in the fentanyl group and 6.7 mL in the remifentanil group.…”