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).