Transcutaneous electrical nerve stimulation and analgesia following inguinal hernioplasties – Preliminary report

Abstract

INTRODUCTION: Inguinal hernioplasty is the most common surgical procedure. Although it is a low-risk surgery, it may present significant postoperative pain. Pharmacological pain relief may result in adverse effects. A double-blind, randomized, prospective, controlled study was conducted to evaluate if transcutaneous electrical nerve stimulation (TENS) analgesia applied during the first 24 h following a Lichtenstein inguinal hernia repair reduces the use of pain relievers in the short-term postoperative period. MATERIALS AND METHODS: A preliminary sample of 24 patients was gathered, according to inclusion and exclusion criteria. Two groups were studied: treatment and control. TENS was applied at a frequency of 100 Hz on the surgical area every 4 h. Both groups received a dose of analgesia during recovery from anesthesia. On-demand intravenous administration of tramadol 50 mg was prescribed during the postoperative period. An electrical muscle stimulator was also placed to the control group, but it was not turned on. Postoperative pain was assessed using the visual analog scale and by the amount and frequency of required pharmacological rescue analgesia. RESULTS: The mean postoperative pain was calculated based on the treatment administered. For the control group, the average was 5.1 (confidence interval [CI]: 3.84–6.35), whereas for the treatment group, it was 0.62 (CI: 0.22–1.01) (P < 0.001). Moreover, requests for rescue analgesia were compared: the TENS-treated group did not ask for rescue analgesia, whereas 57% of the control group requested it (P < 0.001). DISCUSSION: Postoperative analgesia demands a multimodal approach which effectively relieves pain with minimum adverse effects but that is also safe and may be self-administered. Although results are preliminary, in this study we have found a significant difference when using TENS as postoperative analgesia in terms of levels of pain and request for analgesia.