EFFECT OF THE INTENSITY OF TRANSCUTANEOUS ACUPOINT ELECTRICAL-STIMULATION ON THE POSTOPERATIVE ANALGESIC REQUIREMENT

Given the inherent side effects associated with both opioid and nonopi oid analgesic drugs, a nonpharmacologic therapy that could decrease th e need for analgesic medication would be valuable. We designed a sham- controlled study to assess the effect of the intensity of transcutaneo us acupoint electrical stimulation (TAES) on postoperative patient-con trolled analgesia (PCA) requirement for hydromorphone (HM), the incide nce of opioid-related side effects, and the recovery profile after low er abdominal surgery. One hundred one healthy consenting women undergo ing lower abdominal procedures with a standardized general anesthetic technique were randomly assigned to one of four postoperative analgesi c treatment regimens: Group I (n = 26) PCA only; Group II (n = 25), PC A + sham-TAES (no electrical stimulation): Group III (n = 25), PCA + l ow-TAES (4-5 mA of electrical stimulation): Group IV (n = 25), PCA + h igh-TAES (9-12 mA of electrical stimulation). The PCA device was progr ammed to deliver HM, 0.2-0.4 mg intravenously boluses ''on demand,'' w ith a minimum lockout interval of 10 min. The TAES skin electrodes wer e placed at the Hegu acupoint on the nondominant hand and on both side s of the surgical incision. The TAES frequency was set in the dense-an d-disperse mode, alternating at 2 Hz and 100 Hz every 3 s, with stimul ation of the hand and incision alternated every 6 s, The patients in G roups II-IV were instructed to use TAES every 2 h for 30 min while awa ke. After discontinuation of PCA, oral pain medications were administe red on demand. The postoperative PCA-HM requirement, pain scores, opio id-related side effects, and requirements for antiemetic and antipruri tic medication were recorded. High-TAES decreased the HM requirement b y 65% and reduced the duration of PCA therapy, as well as the incidenc e of nausea, dizziness, and pruritus. Low-TAES produced a 34% decrease in the HM requirement compared with only 23% in the ''sham'' TAES gro up. We conclude that high-TAES produced a significant decrease in the PCA opioid requirement and opioid-related side effects after low intra abdominal surgery.