patients may appear serious perineal itching, after injection of dexamethasone sodium phosphate injection its incidence is about 25% ~ 100%, and the incidence of the discomfort in females was much higher than that of the maleTo investigate the effect of propofol pretreatment on perineal pruritus induced by dexamethasone sodium phosphate injection and explore the possible machanisms.

40 patients scheduled for selective surgery,aged 18-65years,ASA physical status I~II,BMI 18~30kg/m2 were selected in this study.The patients were equally randomized into two groups: propofol (P) group and normal saline (N) group, 20 cases in each group. Before anesthesia induction, M group received intravenous injection of 0.3mg/kg propofol , while N group received corresponding intravenous normal saline of the same volume. After 1 min, both groups received intravenous injection of dexamethasone sodium phosphate injection of 10mg. The anesthesiologist assessed perineal irritation in both groups and recorded Ramsay scores,the number of cases, visual analogue scale(VAS) scores ,duration of itching and observed the occurrence of adverse reactions such as dizziness, hypotension and respiratory depression in the two groups.

Inclusion Criteria:

• Elective female surgery patients, ages 18 to 65 years old, ASA Ⅰ or Ⅱ level, body mass index (BMI) of 18 ~ 30 kg/m2.

Exclusion Criteria:

• diabetes mellitus, paresthesia, allergy to narcotic drugs, routine preoperative use of narcotic analgesics, long-term use of hormones, drug and alcohol abuse, communication disorders in psychiatric disorders, pregnancy or lactation, and patients with severe systemic diseases and unwilling to undergo the trial.

female