Objective

2

To observe the effect of preoperative electroacupuncture （EA） pretreatment on postoperative analgesia in patients undergoing total knee arthroplasty （TKA） under general anesthesia.

Methods

2

96 patients undergoing their first unilateral TKA under general anesthesia at Xuzhou Central Hospital were enrolled and randomly divided into an observation group and a control group according to a random table number， with 48 cases in each group. The observation group received EA pretreatment combined with local infiltration anesthesia and patient-controlled intravenous analgesia （PCIA）， while the control group received local infiltration anesthesia and PCIA. Plasma levels of bradykinin （BK）， prostaglandin E2 （PGE2）， substance P （SP）， β-endorphin （β-ep）， and dynorphin （Dyn） before and after surgery， and VAS scores at 12， 24， and 48 hours postoperatively， as well as anesthesia drug usage and adverse reactions， were compared between the two groups.

Results

2

Postoperatively， plasma levels of BK， PGE2， SP， β-ep， and Dyn in both groups differed significantly from their preoperative levels（

P

<

0.01）. The observation group had lower plasma levels of BK， PGE2， and SP than the control group （

P

<

0.05）， and higher levels of β-ep and Dyn （

P

<

0.05）. For resting VAS scores at 12， 24， and 48 hours postoperatively， there was no significant difference between the two groups （

F

=0.694，

P

=0.406）， but intra-group comparisons at each time point showed significant differences （

F

=256.6，

P

<

0.01）. For activity VAS scores at 12， 24， and 48 hours， significant differences were observed between the groups （

F

=7.072，

P

=0.008）， and intra-group comparisons at each time point also showed significant differences （

F

=300.885，

P

<

0.01）. The observation group had a later first press time than the control group （

P

<

0.01）， fewer total PCIA presses（

P

<

0.01）， and fewer cases requiring additional analgesia， though this difference was not statistically significant（

P

>

0.05）. The incidence of nausea and vomiting was lower in the observation group than the control group（

P

<

0.05）， but there were no significant differences in the incidence of dizziness， drowsiness， respiratory depression， or itching between the two groups（

P

>

0.05）.

Conclusion

2

EA pretreatment enhances the analgesic effect of local infiltration anesthesia combined with PCIA in patients undergoing TKA.