BACKGROUND: Controlling postoperative pain after knee replacement while reducing opioid-induced adverse effects and improving outcomes remains an important challenge. To assess the effect of combined capsicum plaster at the Korean hand acupuncture point on opioid consumption and outcomes after total knee replacement.

METHODS: One hundred and two patients, received total knee replacement, were included in a randomized, double-blinded study: 51 patients were in the placebo group, and 51 patients were in K-M26 group. Capsicum plaster was applied at the K-M26 point in K-M26 group, whereas in the placebo group, an inactive tape was fixed at K-M26 point of both hands. The capsicum plaster was applied before induction of anesthesia for 8 h, and attached during 3 days postoperatively. They received postoperative pain treatment with intravenous patient-controlled analgesia (PCA) during the first postoperative 48 h. Visual analog scale (VAS) scores at rest were used to assess pain. Total PCA volume delivered, number of PCA requests, supplemental analgesics, overall satisfaction score and adverse events were evaluated.

RESULTS: K-M26 group reported significant lower VAS and supplemental analgesic doses at 3 days postoperatively compared with placebo group. No significant differences were found in delivered doses and requested number of PCA, and satisfaction score between two groups. There was a tendency of decrease in postoperative nausea and vomiting in K-M26 group, but no significant differences.

CONCLUSIONS: PCA with capsicum plaster at in K-M26 point is thought to be potent and safe for postoperative pain relief after total knee replacement with the lesser adverse events.