Can electrostimulation reduce the requirement for opioids in patients after surgery?

INTERVENTION: Enrolled participants will be randomly assigned to TEAS, sham, or control group (1:1:1). An independent, blinded statistician will generate the block randomization scheme. The table will be managed by an independent researcher who is not involved in the recruitment, treatment, or assessment. The participants will be blinded to the type of treatment. On a patient's arrival in the postanesthesia care unit, the PCA device will be connected to the patient's intravenous line and programmed to deliver 1 ml bolus doses of morphine (1 mg) "on‐demand," with a minimal lockout interval of 10 min and a maximum 4 h dose of 15 mg according to a standardized hospital protocol. PCA therapy will be initiated in the postanesthesia care unit when the patient was sufficiently alert to understand and operate the PCA device. If the patient requires pain medication prior to starting PCA therapy, an incremental dose of metamizole 1 g intravenously, will be administered by the postanesthesia care unit nursing staff. The postoperative PCA analgesic therapy will be supplemented with TEAS/sham therapy, which will start when the patient arrives in the postanesthesia care unit. Stimulation will be performed using four portable coin‐sized electro‐stimulators (StimulAid Inc, Poland). A point‐detection function in the device will confirm the correct localization of the stimulator. The TEAS group will receive mixed frequency stimulation (alternating at 2 and 100 Hz every 3 s) in continuous mode for 30 min at intervals of 2 h. The device will automatically shut off at the end of each 30 min treatment interval. The intensity of the stimulation will be adjusted to each individual to maintain a slight twitching of the regional muscle and achieve De‐Qi sen CONDITION: Postoperative pain in patients undergoing inguinal hernia repair ; Surgery PRIMARY OUTCOME: Total morphine dose received in mg measured using patient‐controlled analgesia (PCA) device in the postoperative period SECONDARY OUTCOME: ; 1. The number of PCA demands, measured by times the button is pressed by the patients in the postoperative period; 2. Pain measured using score on the Visual Analogue Scale prior to surgery and at 4, 8, 12, 16, and 20 hours after surgery; 3. The frequency of opioid‐related side effects recorded by the medical staff during the postoperative observation period; INCLUSION CRITERIA: 1. Male and female patients aged 18–75 years 2. Patients undergoing elective laparoscopic mesh inguinal hernia repair 3. Body mass index 18–30 kg/m² 4. ASA classification I–III 5. Patients provide signed informed consent