Different Dose of Esketamine Inhibiting Response to Laryngeal Mask Airway Insertion

Determation of Median Effective Dose of Propofol Combined With Different Dose of Esketamine Inhibiting Response to Laryngeal Mask Airway Insertion in Female Patients

Objective To prospectively determine the median effective dose (ED50) of propofol for inhibiting a response to laryngeal mask airway (LMA) insertion when combined with different doses of esketamine in female patients.

Methods Fifty-eight female patients (aged 20-60, ASAⅠ-Ⅱ) scheduled for elective hysteroscopy were enrolled and randomly divided into two groups, one administered 0.2 mg/kg of esketamine (K1 group, n = 28) and the other 0.3 mg/kg of esketamine (K2 group, n = 30). The two groups received the corresponding doses of esketamine intravenously, followed by an intravenous injection of propofol (injection time was 30 s). The initial dose of propofol was 2 mg/kg, and the dose ratio of propofol in the adjacent patients was 0.9. If there was a positive reaction to LMA insertion, the dose ratio in the next patient was increased by one gradient, and if not, the dose ratio was decreased by one gradient. The median effective dose (ED50), 95% effective dose (ED95) and 95% confidence interval (95%CI) of propofol for inhibiting a response to LMA insertion in the two esketamine groups were calculated using a probit analysis.

Inclusion Criteria:

• women undergoing gynaecological hysteroscopy and surgery resulting from any indication
• age: from 20 to 60 years old
• body mass index (BMI): 18-30 kg/m2
• American Society of Anesthesiologists Physical Status score: grade I-II
• voluntary participation in this study

Exclusion Criteria:

• pregnant and lactating women
• patients with a history of propofol allergy, uncontrolled hypertension, hyperthyroidism, severe cardiopulmonary diseases, airway stenosis and mental diseases
• those who have recently taken or are taking psychotropic drugs or analgesic drugs
• patients allergic to or addicted to esketamine