Electroacupuncture combined with continuous adductor canal block for postoperative analgesia in patients undergoing...

To observe the efficacy of electroacupuncture (EA)combined with continuous adductor canal block (CACB)for postoperative analgesia in patients undergoing total knee arthroplasty (TKA), and to explore its effect on pain factor levels.

Eighty-two patients with knee osteoarthritis undergoing unilateral TKA were randomly divided into an observation group and a control group, with 41 patients in each group. The patients in the control group were treated with CACB under ultrasound guidance on the affected side after removal of the endotracheal tube. In the observation group, electroacupuncture therapy was added on day 1-7 after operation; the acupoints included Hegu (LI 4), Zusanli (ST 36), Taichong (LR 3), Taixi (KI 3), Yinlingquan (SP 9)and Yanglingquan (GB 34), with disperse-dense wave, in frequency of 1 Hz/30 Hz, 30 min each session, once a day. The knee joint range of motion was compared between the two groups before operation and on postoperative day 1, 3, 7, and 14. The pain visual analog scale (VAS)scores were compared 6, 12, 24, and 48 h after operation. The number of times that the pain pump was pressed within 48 h after operation and the number of remedial analgesia were also compared. Serum levels of prostaglandin E2 (PGE2)and β-endorphin (β-EP)were measured preoperatively and at 6, 12, 24, and 48 h after operation. Adverse reaction rates within 48 h after operation were documented.

On postoperative day 1, 3, and 7, the observation group exhibited greater knee joint range of motion than that in the control group (P<0.05). At 6, 12, 24, and 48 h after operation, VAS scores at rest and during activity in the observation group were lower than those in the control group (P<0.05). The observation group had lower numbers of pain pump use and remedial analgesia within 48 h after operation than those in the control group (P<0.05). Serum PGE2 levels were lower in the observation group at 6, 12, and 24 h after operation (P<0.05), while serum β-EP levels were higher (P<0.05) than those in the control group. There was no statistical difference in the incidence of adverse reactions within 48 h after operation between the two groups (P>0.05).

EA therapy could enhance the analgesic effect of CACB in TKA patients, possibly by decrease the content of PGE2 and increase the content of β-EP, with a high level of safety.