Time interval between alfentanil and rocuronium administration necessary to prevent rocuronium-induced withdrawal movement.

BACKGROUND: We aimed to determine the time interval between alfentanil and rocuronium administration, at a 50% probability of preventing pain-induced withdrawal movement from rocuronium injection (TimeAR50). METHODS: A total of 64 patients scheduled for general anesthesia were enrolled in this study (33 men and 31 women). Anesthesia was induced with target-controlled infusion of propofol, at an effect-site target concentration of 3 µg/mL. Then, alfentanil 15 µg/kg was injected for 30 s. After 60 s, rocuronium 0.6 mg/kg was administered to the first patient. The Dixon's up-and-down method was used to determine the time interval for each subsequent patient (interval of 5 s). Mean arterial pressure (MAP) and heart rate (HR) were recorded at three time points: T0, pre-induction; T1, before rocuronium injection; and T2, 1 min after rocuronium injection. RESULTS: The TimeAR50 ± standard deviation (SD) was 5.6 ± 3.7 s and 21.9 ± 5.6 s in the male and female patients, respectively. Based on the probit regression, the TimeAR50 was 4.7 s (95% confidence interval [CI], 1.2-7.6 s) and 20.3 s (95% CI, 7.7-26.1 s) in the male and female patients, respectively. The TimeAR95 was 10.6 s (95% CI, 7.7-25.3 s) and 35.0 s (95% CI, 28.1-95.5 s) in the male and female patients, respectively, with significantly higher values in females than in males (P < 0.001). Compared with the T0, MAP and HR decreased significantly at T1 and T2 in both groups. CONCLUSION: The TimeAR50 required for preventing rocuronium-induced withdrawal movement were 4.7 s and 20.3 s in male and female patients, respectively. TRIAL REGISTRATION: This study was registered with the Chinese Clinical Trials Registry on April 7, 2021 (URL: http://www.chictr.org.cn . Registry number: ChiCTR2100045137 ) .

[Effect of cardiopulmonary bypass on the expression of survivin in neutrophils].

OBJECTIVE: To investigate the effects of cardiopulmonary bypass on neutrophils apoptosis and the expression of survivin. METHODS: Ten patients who scheduled for cardiac surgery under cardiopulmonary bypass were recruited as study group and 10 healthy volunteers as control. Blood samples were obtained before operation, at the end of surgery, and at 24 hours postoperatively. Neutrophils were isolated by density gradient centrifugation and its apoptosis were evaluated by fluorescent microscope and flow cytometry. The expression of survivin protein was examined by Western blotting analysis. Expression level of survivin mRNA was detected by RT-PCR. RESULTS: The apoptotic rate of neutrophils decreased significantly at the end of surgery (P < 0.01), and was still lower at 24 hours postoperatively than before operation (P < 0.05). The expression ratios of survivin protein and mRNA were increased at the end of surgery (P < 0.01), and decreased gently at 24 hours postoperatively but was still higher than before operation (P < 0.05). CONCLUSION: Cardiopulmonary bypass could inhibit neutrophils apoptosis and increase the expression of survivin. The decrease of neutrophils apoptosis was correlated with high expression of survivin.