Abstract: Objective To investigate the anesthetic effect of ultrasound-guided pectoral nerve block (PECS) and thoracic paravertebral block (TPVB) in breast cancer patients undergoing radical surgery. Methods A total of 102 breast cancer patients admitted to our hospital from April 2021 to April 2024 were selected and all received radical mastectomy for breast cancer.They were randomly divided into Group A and Group B by the random number table method,with 51 cases in each group.Group A used PECS,and Group B used TPVB.The perioperative indicators,postoperative pain,stress response indicators,inflammatory response indicators,cognitive function,and untoward reactions of both groups were compared. Results There was no statistically significant difference in intraoperative infusion，blood loss volume，operation and hospital stay between group A and group B (P>0.05).The visual analogue scale (VAS) scores of group A at different time points after surgery were prominently lower than those of group B (P<0.05).After surgery,tumor necrosis factor-α (TNF-α),adrenaline (E),interleukin-6 (IL-6),and norepinephrine (NE) in group A were prominently lower than those in group B (P<0.05).The Mini Mental State Examination (MMSE) score in group A was prominently higher than that in group B (P<0.05).Moreover,there was no statistically significant difference in the incidence of hypotension,vomiting,etc(P>0.05).Conclusion Ultrasound guided PECS for breast cancer patients undergoing radical mastectomy has less postoperative pain response,less stress injury,and ideal analgesic effect.

Key words: breast cancer; ultrasound guidance; pectoral nerve block; thoracic paravertebral block; analgesic effect