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Published on: July 11, 2025
Effects of transcutaneous electrical acupuncture point stimulation on peripheral capillary oxygen saturation in
Yongming Chen1,2, Yin Gong2, Xiaorong Huai1,2
1Department of Anesthesiology, The Second Affiliated Hospital of Soochow University, Suzhou, China.
Introduction:
This study investigated whether transcutaneous electrical acupuncture point stimulation (TEAS) at PC6 can reduce the proportion of elderly patients experiencing a drop of ⩾4% in peripheral capillary oxygen saturation (SpO2) while undergoing colonoscopy under sedation.
Methods:
A total of 32 elderly patients (aged ⩾ 65 years) scheduled for colonoscopy were randomly assigned in a 1:1 ratio to receive either real or sham TEAS (treatment or control groups, respectively). Each patient received oxygen (2 L/min) delivered routinely via nasal cannula. The treatment group was given TEAS at PC6 for 20 min at 2 Hz frequency and 6 mA intensity; the control group underwent the same procedures but with zero frequency/intensity. SpO2 and other physiological parameters were measured prior to sedation and colonoscopy (baseline) and at seven other timepoints through departure from recovery. Depth of anesthesia was measured using a Narcotrend monitor.
Results:
Significantly fewer patients in the treatment group experienced a ⩾4% decrease from baseline SpO2 (2/16) than patients in the control group (10/16; p = 0.004). The two groups were comparable with regard to respiratory rate, systolic and diastolic blood pressures, mean arterial pressure, and heart rate.
Conclusion:
TEAS applied at PC6 with 2 Hz frequency was feasible and may be helpful in reducing the rate of hypoxia in elderly patients during colonoscopy.Trial registration number: NCT03775122 (ClinicalTrials.gov).
