Effects of Electroacupuncture at NP82 and SP15 on Bowel Motility in Healthy Subjects

University of Medicine and Pharmacy at Ho Chi Minh City30 enrolled

Overview

This study aims to investigate how a specific combination of electroacupuncture points, Tongbian (NP82) and Daheng (SP15), affects bowel movements in healthy volunteers. Constipation is a significant health issue, especially for post-stroke patients, and current treatments like laxatives often have unwanted side effects. The researchers want to determine if stimulating these two acupuncture points can objectively increase the frequency of bowel activity. Participants will undergo a three-stage procedure: a 30-minute period of baseline bowel sound recording, followed by 20 minutes of electroacupuncture stimulation at the specific points, and a final 30-minute recording period after the intervention. Throughout the study, an advanced digital stethoscope (3M™ Littmann® CORE) will be used to record bowel sounds objectively. This data will then be analyzed to measure any significant changes in bowel motility caused by the acupuncture.

Background and Rationale: Bowel motility is a fundamental physiological function regulated by the autonomic nervous system. This study explores the potential of electroacupuncture (EA) to modulate this activity using a unique acupoint combination: Dai Hoanh (SP15), a classic point known for regulating the Spleen and Stomach, and Thong Tien (NP82), a newly proposed "extra point" specifically indicated for treating paralysis-related constipation in traditional literature. The study aims to provide the first modern scientific evidence for the effectiveness of NP82 in stimulating bowel motility. Methodology: The study follows a before-and-after intervention design involving 30 healthy volunteers. To ensure objective measurement, bowel sounds are recorded using the 3M™ Littmann® CORE Digital Stethoscope, which amplifies sounds and allows for computerized analysis, overcoming the subjectivity of traditional auscultation. The procedure consists of three phases: 1. Baseline Phase: Continuous 30-minute recording of bowel sounds to establish a physiological reference. 2. Intervention Phase: Simultaneous 20-minute recording during EA. Sterile needles (0.30×40mm) are inserted into NP82 and SP15 points until "De Qi" sensation is achieved. Stimulation utilizes a dense-disperse wave at a 10 Hz frequency, with intensity adjusted (0.1-1 mA) based on participant tolerance. 3. Post-intervention Phase: Continuous 30-minute recording after needle removal to evaluate sustained effects. Data Analysis: The primary quantitative variable is the Bowel Sound Interval (SSI), defined as the time between bowel sound events. Statistical analysis will be performed using Stata 17.0, employing Paired t-tests or Wilcoxon signed-rank tests to compare bowel sound frequencies across the three phases with a significance level of p \< 0.05.

Interventions

Electroacupuncture at NP82 (Tongbian) and SP15 (Daheng)PROCEDURE

The intervention is performed by practitioners with at least 3 years of experience. Sterile acupuncture needles (0.30×40mm) are inserted vertically into the Tongbian (NP82 - located 3 cun lateral to the umbilicus) and Daheng (SP15 - located 4 cun lateral to the umbilicus) acupoints. Insertion depth ranges from 20 to 65 mm depending on the participant's body type, aiming to achieve the "De Qi" sensation (aching, heaviness, and tension). Electrical stimulation is applied using a Hwato SDZ-III device with a dense-disperse wave at a frequency of 10 Hz for 20 minutes. The current intensity is adjusted (0.1-1 mA) until a mild muscle vibration is visible without causing pain to the participant.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 30 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Healthy volunteers aged 18 years and older. * No symptoms related to constipation after comprehensive evaluation based on Rome IV criteria. * No gastrointestinal symptoms (abdominal pain, diarrhea, blood in stool, constipation, or bloating) in the 4 weeks prior to study participation. * No use of medications that promote or inhibit bowel motility in the 4 weeks prior to participation (including prokinetics, laxatives, antispasmodics, or opioids). * Fasting for at least 4 hours before the study session. * No mental or intellectual disorders; capable of understanding the acupuncture and assessment procedures. * Willingness to participate and signed informed consent form. Exclusion Criteria: * Participants with severe medical conditions (heart, brain, liver, kidney, hematological system, infectious diseases, cancer, or psychiatric disorders). * Metabolic or functional disorders such as irritable bowel syndrome (IBS), thyroid dysfunction, or glucose/lipid metabolism disorders. * Use of bowel motility-altering medications within the 4 weeks prior to participation. * Participation in other clinical trials within the last 2 months. * Received acupuncture treatment within the last month. * Skin ulcers, abscesses, or infections at the acupuncture sites. * Known metal allergy or severe needle phobia.

Outcomes

Primary Outcomes

Bowel Sound Interval (SSI)

SSI is the time interval between the end of one bowel sound event and the start of the next. Bowel sounds are recorded and quantified using the 3M™ Littmann® CORE Digital Stethoscope and analyzed with Stata 17.0 software to determine changes in bowel motility.

Time frame: Continuous recording across three phases: Baseline (30 minutes before intervention), During Intervention (20 minutes), and Post-intervention (30 minutes).

Secondary Outcomes

Minimum SSI Ratio (SSIR)

SSIR is calculated as the ratio of the minimum Bowel Sound Interval (SSI) during or after the intervention (Ba) to the minimum SSI before the intervention (Bb). SSI values are derived from digital recordings of bowel sounds captured by a 3M™ Littmann® CORE Digital Stethoscope. The analysis focuses on 10-minute windows within each phase to determine the maximum increase in bowel motility compared to the baseline.

Time frame: The total study duration is 80 minutes, consisting of: (1) Baseline phase: 30 minutes before intervention; (2) Intervention phase: 20 minutes during electroacupuncture; and (3) Post-intervention phase: 30 minutes after needle removal.