TEAS for Sedation During ERCP

1. The goal of this clinical trial is to learn if transcutaneous electrical acupoint stimulation (TEAS), a non-invasive therapy that applies mild electrical current to specific points on the skin, can help patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) better tolerate the procedure and experience fewer complications related to sedation. It will also test whether TEAS improves procedural success and patient satisfaction. 2. The main questions the study aims to answer are: (1)Does TEAS reduce the incidence of sedation-related adverse events (such as low blood oxygen, low blood pressure, or breathing problems) during ERCP? (2)Does TEAS improve patient comfort and reduce the need for additional sedative medications during the procedure? (3)Does TEAS lead to faster recovery and higher patient and physician satisfaction? 3.Researchers will compare two approaches: 1. Active TEAS: Electrical stimulation at specific points on the legs and arms before and during ERCP. 2. Sham TEAS: Pads placed on the same points but no electrical stimulation delivered (the device appears active). 4.All participants will receive standard conscious sedation with meperidine and diazepam, which is commonly used for ERCP in many centers. Participants will be randomly assigned to one of the two groups. The study will measure sedation-related complications, pain levels, medication requirements, recovery times, and satisfaction scores.

1. Background and Rationale: Endoscopic retrograde cholangiopancreatography (ERCP) is a complex procedure essential for diagnosing and treating various pancreaticobiliary disorders. Adequate sedation is critical for patient comfort and procedural success. Traditional conscious sedation with meperidine and diazepam remains widely used, particularly in resource-limited settings, but is associated with risks of respiratory depression, hypoxemia, hypotension, and inadequate sedation. Transcutaneous electrical acupoint stimulation (TEAS) is a non-invasive modality derived from traditional acupuncture principles that delivers controlled electrical currents to specific acupoints via surface electrodes. TEAS has been shown to exert analgesic effects through the release of endogenous opioid peptides, modulate autonomic nervous system function, reduce perioperative opioid requirements, and decrease the incidence of postoperative nausea and vomiting. However, robust evidence on its efficacy and safety specifically during ERCP with traditional conscious sedation is lacking. This trial aims to rigorously evaluate whether adjunctive TEAS improves procedural safety, tolerance, and clinical outcomes in patients undergoing ERCP. 2. Study Design and Methodology: This is a prospective, randomized, sham-controlled, single-blind, parallel-group trial. Patients scheduled for elective diagnostic or therapeutic ERCP will be assessed for eligibility. Eligible and consenting participants will be randomly assigned (1:1) using a computer-generated random allocation sequence with permuted blocks of variable sizes (4 and 6), with allocation concealment in sequentially numbered, opaque, sealed envelopes. Participants will be allocated to one of two groups: 1. Active TEAS Group: Receives real TEAS stimulation applied bilaterally to four predefined acupoints: Yinlingquan (SP9), Yanglingquan (GB34), Xuehai (SP10), and Neiguan (PC6). Acupoint locations will be determined according to WHO Standard Acupuncture Point Locations. Disposable self-adhesive electrodes (diameter 3 cm) will be connected to a Hwato SDZ-III electronic acupoint stimulator (Suzhou Medical Supplies Factory Co., Ltd., China). Stimulation parameters are set to dense-disperse wave mode (alternating frequencies of 2 Hz and 100 Hz, each for 3 seconds). The intensity is adjusted to the patient's maximum tolerable level (typically 2-5 mA). Stimulation begins 30 minutes before the procedure and continues throughout the endoscopic procedure. 2. Sham TEAS Group: Receives identical electrode placement at the same four bilateral acupoints using the same device, but no electrical current is delivered. The device appears active (indicator lights on) to maintain blinding. All patients in both groups are informed that they may or may not feel any sensation during the stimulation, which is normal. All participants receive standardized conscious sedation with intravenous meperidine (0.5 mg/kg) and diazepam (0.05 mg/kg) administered by an anesthesiologist blinded to group assignment. ERCP procedures are performed by experienced gastroenterologists (each with \>300 prior ERCPs) who are also blinded to group assignment. A designated research assistant who is not involved in patient care, outcome assessment, or data analysis performs the TEAS or sham-TEAS intervention and ensures that the device display is shielded from the patient's view. 3.Scientific Justification: The selection of specific acupoints (SP9, GB34, SP10, PC6) is based on traditional Chinese medicine principles and modern physiological understanding: targeting points associated with visceral analgesia (GB34, SP9), gastrointestinal motility regulation and anti-emesis (PC6, ST36-like effects), and calming effects (PC6). The sham-controlled design is crucial for isolating the specific effects of electrical neuromodulation from non-specific placebo effects. This trial addresses a significant gap in optimizing sedation for ERCP by evaluating a readily deployable, non-pharmacological adjunctive strategy that could enhance patient safety and procedural quality, particularly in settings where newer sedative agents or dedicated anesthesia services are not readily available.