Effect of neoadjuvant chemotherapy for ovarian cancer on sedative potency of propofol and oxycodone for anesthesia induction

Abstract

Objective To evaluate the effect of neoadjuvant chemotherapy for ovarian cancer on the sedative potency of propofol and oxycodone for anesthesia induction. Methods Sixty-eight American Society of Anesthesiologists physical status Ⅰor Ⅱ patients, aged 40-64 yr, with body mass index of 20-30 kg/m2, scheduled for elective radical resection of ovarian cancer with general anesthesia, were divided into into 2 groups(n=34 each)according to whether the patients received neoadjuvant chemotherapy before surgery: neoadjuvant chemotherapy group(groupⅠ)and non-chemotherapy group(group Ⅱ). Patients received 3 cycles of chemotherapy(21 days for 1 cycle), chemotherapy regimen was paclitaxel and carboplatin, and patients underwent surgery after 3 weeks of chemotherapy in group Ⅰ.Anesthesia was induced with Ⅳ oxycodone 0.2 mg/kg.Propofol was given by target-controlled infusion 4 min later, and the effect-site concentration(Ce)of propofol was determined by up-and-down technique, with the initial Ce 1.0 μg/ml and the ratio between the two successive Ces 1.09.The median-effective target plasma concentration(EC50)and 95% confidence interval of propofol causing loss of consciousness were calculated using Probit analysis. Results The EC50 and 95% confidence interval of propofol causing loss of consciousness were 1.22 μg/ml(1.14-1.30 μg/ml)and 1.74 μg/ml(1.57-3.19 μg/ml)in group Ⅰ and group Ⅱ, respectively.Compared with group Ⅱ, the EC50 of propofol causing loss of consciousness was significantly decreased in group Ⅰ(P<0.05). Conclusion Neoadjuvant chemotherapy for ovarian cancer can enhance the sedative potency of propofol and oxycodone for anesthesia induction. Key words: Oxycodone; Chemotherapy, adjuvant; Propofol; Sedation