Objective To explore the application value of esketamine combined with ultrasound-guided serratus anterior plane block(SAPB) in modified radical mastectomy of breast cancer.

Methods A total of 60 patients aged 20-60 years and BMI 18 ~ 24.5 kg/m² scheduled by modified radical mastectomy under laryngeal mask general anesthesia were selected, and randomly divided into the observation group(group S) and control group(group C).The group C received the anterior serrated muscle plane block under ultrasound guidance and 0.25% ropivacaine as local anesthetics.On the basis of the control group C, the group S was given intravenous esketamine 0.25 mg/kg 30 min before the end of the operation.The postoperative controlled intravenous analgesia(PCIA) was given in two groups.The perioperative observation indexes, postoperative sedation, analgesia scores, adverse reactions and complication rate of SPAB were observed in two groups.

Results The time of first analgesic pump compression in the group S was longer than that in group C, the number of analgesic pump compression after 48 h of surgery and dosage of sufentanil after 24 h and 48 h of surgery in the group S were lower than those in group C, the degree of analgesia after 3 h, 6 h and 12 h of surgery in the group S were higher than that in group C, and the total incidence rate of adverse reactions in the group S was lower than that in group C(P < 0.05).There was no statistical significance in the sedation scores after 3 h, 6 h, 12 h, 24 h and 48 h and pain scores after 24 h and 48 h of operation between two groups(P>0.05).

Conclusions Esketamine combined with ultrasound-guided SAPB has ideal analgesic effects and less adverse reactions in modified radical mastectomy.