Effect of sufentanil on bispectral index in the elderly

Substance-dependent EEG during recovery from anesthesia and optimization of monitoring

The electroencephalographic (EEG) activity during anesthesia emergence contains information about the risk for a patient to experience postoperative delirium, but the EEG dynamics during emergence challenge monitoring approaches. Substance-specific emergence characteristics may additionally limit the reliability of commonly used processed EEG indices during emergence. This study aims to analyze the dynamics of different EEG indices during anesthesia emergence that was maintained with different anesthetic regimens. We used the EEG of 45 patients under general anesthesia from the emergence period. Fifteen patients per group received sevoflurane, isoflurane (+ sufentanil) or propofol (+ remifentanil) anesthesia. One channel EEG and the bispectral index (BIS A-1000) were recorded during the study. We replayed the EEG back to the Conox, Entropy Module, and the BIS Vista to evaluate and compare the index behavior. The volatile anesthetics induced significantly higher EEG frequencies, causing higher indices (AUC > 0.7) over most parts of emergence compared to propofol. The median duration of "awake" indices (i.e., > 80) before the return of responsiveness (RoR) was significantly longer for the volatile anesthetics (p < 0.001). The different indices correlated well under volatile anesthesia (rs > 0.6), with SE having the weakest correlation. For propofol, the correlation was lower (rs < 0.6). SE was significantly higher than BIS and, under propofol anesthesia, qCON. Systematic differences of EEG-based indices depend on the drugs and devices used. Thus, to avoid early awareness or anesthesia overdose using an EEG-based index during emergence, the anesthetic regimen, the monitor used, and the raw EEG trace should be considered for interpretation before making clinical decisions.

Effects of different depth of anesthesia on perioperative inflammatory reaction and hospital outcomes in elderly patients undergoing laparoscopic radical gastrectomy

Background

To investigate the effect of different depth of anesthesia on inflammatory factors and hospital outcomes in elderly patients undergoing laparoscopic radical gastrectomy for gastric cancer, in order to select an appropriate depth of anesthesia to improve the prognosis of patients undergoing surgery and improve the quality of life of patients.

Methods

A total of 80 elderly patients aged 65 and above who underwent laparoscopic radical gastrectomy in our hospital were by convenience sampling and randomly divided into two groups : 55 groups ( group H ) and 45 groups ( group L ), 40 cases in each group. The depth of anesthesia was maintained using a closed-loop target-controlled infusion system: the EEG bispectral index was set to 55 in the H group and 45 in the L group. Venous blood samples were collected 2 h (T2), 24 h (T3) and 72 h (T4) after the start of surgery. The intraoperative dosage of propofol and remifentanil, operation duration, postoperative PACU stay time, intraoperative consciousness occurrence, postoperative hospital stay and postoperative pulmonary inflammatory events were recorded.

Results

The patient characteristic of the two groups had no statistical difference and were comparable (P > 0.05). The intraoperative dosage of propofol in group H was lower than that in group L (P < 0.05). Compared with the L group, the plasma IL-6 and IL-10 concentrations in the H group were significantly increased at T2 (P < 0.05), and the plasma IL-10 concentration was significantly increased at T4 (P < 0.05). The plasma concentrations of IL-6 and IL-10 were higher in both groups at T2, T3 and T4 than at T1, while at T4, the concentration of TNF-α in group H was higher than at T1 (P < 0.05).

Conclusion

When the BIS value of the depth of anesthesia is 45, the perioperative release of inflammatory factors in elderly patients with laparoscopic radical gastrectomy for gastric cancer is less than BIS 55, and does not affect the prognosis.

Application of propofol combined with sevoflurane anesthesia in staged hepatectomy liver detachment and portal vein ligation

The aim of the present study was to investigate the application of propofol combined with sevoflurane anesthesia in associating liver partition and portal vein ligation for staged hepatectomy (ALPPS). A retrospective analysis of 40 patients with liver cancer who underwent ALPPS was performed. The study included 21 (control group) and 19 (observation group) patients who were administered propofol anesthesia and propofol in combination with sevoflurane anesthesia, respectively. Changes in liver function indicators, routine blood parameters and blood coagulation function, as well as cognitive function (mini-mental state examination) were recorded. The total bilirubin and direct bilirubin levels and the alanine aminotransferase (ALT) level after the first- and second-stage operation in the two groups was also higher than that prior to the first-stage operation (P<0.05), and the ALT level was significantly lower in the two groups after the second-stage operation compared with that prior to the second-stage operation (P<0.05). The AST level after the first- and second-stage operation was lower than that prior to the first- and second-stage operation, respectively (P<0.05). The white blood cell count after the second-stage operation was significantly lower compared with that prior to the second-stage operation (P<0.05). The plasma fibrinogen (FIB) level was higher after the first-stage operation compared with that prior to the first-stage operation (P<0.05). The prothrombin time in the two groups of patients was higher after the second-stage operation compared with that prior to the second-stage operation (P<0.05), whereas the FIB level was lower (P<0.05) and the international normalized ratio was not significantly different (P>0.05). The degree of cognitive decline prior to the first/second-stage operation, according to mini-mental state examination scores, was different from that after the first/second-stage operation (P<0.05). In conclusion, propofol combined with sevoflurane has a good application value in ALPPS.

The effects of different doses of dexmedetomidine on the requirements for propofol for loss of consciousness in patients monitored via the bispectral index: a double-blind, placebo-controlled trial

BACKGROUND

The α₂-adrenergic agonist dexmedetomidine (DEX) is a sedative and can be used as an adjunct to hypnotics. The study sought to evaluate the effects of different doses of DEX on the requirements for propofol for loss of consciousness (LOC) in patients monitored via the bispectral index (BIS).

METHODS

In this randomized, double-blind, three arm parallel group design and placebo-controlled trial, 73 patients aged between 18 and ~ 65 years with a BMI range of 18.0-24.5 kg·m^- 2 and an American Society of Anesthesiologists (ASA) grade I or II who were scheduled for general anesthesia at the General Hospital of Ningxia Medical University were included in this study. Anesthesiologists and patients were blinded to the syringe contents. All patients were randomly assigned in a 1:1:1 ratio to receive a 0.5 μg·kg^- 1 DEX infusion (0.5 μg·kg^- 1 DEX group; n = 24), a 1.0 μg·kg^- 1 DEX infusion (1.0 μg·kg^- 1 DEX group; n = 25) or a saline infusion (control group; n = 24) for 10 min. Propofol at a concentration of 20 mg·kg^- 1·h^- 1 was then infused at the end of the DEX or saline infusion. The propofol infusion was stopped when the patient being infused lost consciousness. The primary endpoint were propofol requirements for LOC and BIS value at LOC.

RESULTS

The data from 73 patients were analyzed. The propofol requirements for LOC was reduced in the DEX groups compared with the control group (1.12 ± 0.33 mg·kg^- 1 for the 0.5 μg·kg^- 1 DEX group vs. 1.79 ± 0.39 mg·kg^- 1 for the control group; difference, 0.68 mg·kg^- 1 [95% CI, 0.49 to 0.87]; P = 0.0001) (0.77 ± 0.27 mg·kg^- 1 for the 1.0 μg·kg^- 1 DEX group vs. 1.79 ± 0.39 mg·kg^- 1 for the control group; difference, 1.02 mg·kg^- 1 [95% CI, 0.84 to 1.21]; P = 0.0001). The propofol requirements for LOC was lower in the 1.0 μg·kg^- 1 DEX group than the 0.5 μg·kg^- 1 DEX group (0.77 ± 0.27 mg·kg^- 1 vs. 1.12 ± 0.33 mg·kg^- 1, respectively; difference, 0.34 mg·kg^- 1 [95% CI, 0.16 to 0.54]; P = 0.003). At the time of LOC, the BIS value was higher in the DEX groups than in the control group (67.5 ± 3.5 for group 0.5 μg·kg^- 1 DEX vs. 60.5 ± 3.8 for the control group; difference, 7.04 [95% CI, 4.85 to 9.23]; P = 0.0001) (68.4 ± 4.1 for group 1.0 μg·kg^- 1 DEX vs. 60.5 ± 3.8 for the control group; difference, 7.58 [95% CI, 5.41 to 9.75]; P = 0.0001).

CONCLUSION

The study showed that DEX (both 0.5 and 1.0 μg·kg^- 1 DEX) reduced the propofol requirements for LOC. DEX pre-administration increased the BIS value for LOC induced by propofol.

CLINICAL TRIAL REGISTRATION

The study was registered at ClinicalTrials.gov (trial ID: NCT02783846 on May 26, 2016).

ED50 of propofol in combination with low-dose sufentanil for intravenous anaesthesia in hysteroscopy

OBJECTIVES

Sufentanil has favourable pharmacodynamic and pharmacokinetic properties as an opioid, and it is usually co-administered with propofol as intravenous anaesthesia for hysteroscopic examination or therapeutic surgery. However, the optimal dosage of propofol when it is co-administered with low-dose sufentanil has not yet been established. This study was designed to find the median effective dose of propofol for intravenous anaesthesia when combined with low-dose sufentanil.

METHODS

Fifty-four patients were enrolled and randomized into two groups in this prospective study. Sufentanil 0.2 μg/kg (Group A) or 0.1 μg/kg (Group B) was given intravenously before speculum placement. The initial propofol dose was set at 2 mg/kg and varied by 0.1 mg/kg according to the sequential allocation up-and-down rule designed by Dixon and Massey. Respiratory depression, duration of initial dose of propofol, total drug quantity administered and recovery time were recorded.

RESULTS

The ED50 of propofol was 1.651 mg/kg (95% CI, 1.561-1.722 mg/kg) in Group A and 1.991 mg/kg (95% CI, 1.902-2.081 mg/kg) in Group B. The ED95 of propofol was 1.827 mg/kg (95% CI, 1.746-2.236 mg/kg) in Group A and 2.153 mg/kg (95% CI, 2.070-2.73 7 mg/kg) in Group B. The initial and total dosage of propofol in Group A were significantly lower than those in Group B, but the incidence of respiratory depression in Group A (26.67%) was significantly higher than that in Group B (4.17%).

CONCLUSION

The ED50 values for propofol when co-administered with low-dose sufentanil for intravenous anaesthesia in hysteroscopy were 1.651 mg/kg (sufentanil 0.2 μg/kg) and 1.991 mg/kg (sufentanil 0.1 μg/kg). (www.chictr.org.cn, registration number: ChiCTR1900021224).