Frequency of Electrical Acupoint Stimulation on Hypotension During Induction (FRESH)

The Influence of Electrical Acupoint Stimulation at Different Frequencies on Hemodynamics During Anesthesia Induction

Within 30 minutes before anesthesia, acupoint electrical stimulation at different frequencies were applied at Neiguan and Jian Shi. The changes in blood pressure during the anesthesia induction period were compared between the high-frequency group and the low-frequency group.

Study Overview

• Status: Not yet recruiting
• Conditions: Hypotension; Anesthesia
• Intervention / Treatment: Other: electrical acupoint stimulation; Other: electrodes pasted; Other: high-frequency electrical stimulation; Other: low-frequency electrical stimulation

• Study Type: Interventional
• Enrollment (Estimated): 84
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Zhihong Lu; Phone Number: 86-13891975018; Email: deerlu23@163.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• aged over 65 yrs old
• scheduled for surgery under general anesthesia

Exclusion Criteria:

• American society of anesthesiologists status over 3
• severe cardiac or respiratory dysfunction
• severe cardiac arrhythmia
• uncontrolled diabetes
• systolic arterial pressure over 180 mmHg

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: High-frequency; The electrical stimulation is provided at a frequency of 100Hz	Other: electrical acupoint stimulation; electrical acupoint stimulation are administered at Neiguan and Jian Shi. The stimulation starts at 15 minutes before anesthesia induction and ends at 15 minutes after anesthesia induction.; Other: electrodes pasted; Electrodes are pasted at Neiguan and Jianshi; Other: high-frequency electrical stimulation; The frequency of electrical stimulation is 100Hz
Experimental: Low-frequency; The electrical stimulation is provided at a frequency of 2Hz	Other: electrical acupoint stimulation; electrical acupoint stimulation are administered at Neiguan and Jian Shi. The stimulation starts at 15 minutes before anesthesia induction and ends at 15 minutes after anesthesia induction.; Other: electrodes pasted; Electrodes are pasted at Neiguan and Jianshi; Other: low-frequency electrical stimulation; The frequency of electrical stimulation is 2Hz
Sham Comparator: No stimulation; Only electrodes are pasted	Other: electrodes pasted; Electrodes are pasted at Neiguan and Jianshi

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
incidence of hypotension	Hypotension is defined as a Mean arterial pressure (MAP) reduction of more than 20% from baseline or a MAP less than 65 mm Hg for at least 1 minute. The baseline MAP is measured during the 5 minutes before start of intervention	from start of anesthesia induction to 15 minutes after induction

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The area under the curve representing the change in mean arterial pressure during the induction period relative to the baseline.	The area under the curve (AUC) below baseline mean arterial pressure (MAP) is calculated as: ∑ (((Si - Sbaseline)+(Si-1 - Sbaseline))/2 × ΔX) where Sbaseline is the baseline MAP, Si is the MAP at the i-th minute (i = 1…15), and ΔX is the time interval between two measurements.	from start of induction to 15 minutes after induction
The dosage of vasoactive drugs	Any MAP drop by more than 20% from baseline or a MAP less than 65 mm Hg for at least 1 minute within the first 15 minutes after general anesthesia induction triggered the administration of norepinephrine boluses (5 μg). If hypotension persisted after 2 boluses, a norepinephrine infusion (0.02-0.3 μg/kg/min) was initiated and continued until the MAP became stable and reached 65 mm Hg or higher. If hypotension reoccurred, 2 boluses of norepinephrine were repeated.	from start of induction to 15 minutes after induction
lowest MAP		from start of induction to 15 minutes after induction
standard deviation of R-R intervals (SDRR)	assessed from the electrocardiography, key index of heart rate variability (HRV)	from start of induction to 15 minutes after induction
ratio of low-frequency HRV/high-frequency HRV (LF/HF ratio)	assessed from the electrocardiography,High-frequency HRV (HF-HRV) at 0.15-0.4 Hz and low-frequency HRV (LF-HRV) at 0.04-0.15 Hz	from start of induction to 15 minutes after induction

Collaborators and Investigators

• Sponsor: Zhihong LU

Publications and helpful links

General Publications

• Kaduk K, Petrella A, Muller SJ, Koenig J, Kroemer NB. Non-Invasive Auricular Vagus Nerve Stimulation Decreases Heart Rate Variability Independent of Caloric Load. Psychophysiology. 2025 Feb;62(2):e70017. doi: 10.1111/psyp.70017.
• Chaitman BR, Bitar SR. Is ST segment elevation non-Q-wave myocardial infarction after thrombolytic therapy a new clinical entity that requires an invasive management strategy? J Am Coll Cardiol. 2001 Jan;37(1):26-9. doi: 10.1016/s0735-1097(00)01053-6. No abstract available.

Study record dates

Study Major Dates

• Study Start (Estimated): March 1, 2026
• Primary Completion (Estimated): August 1, 2026
• Study Completion (Estimated): November 1, 2026

Study Registration Dates

• First Submitted: February 20, 2026
• First Submitted That Met QC Criteria: February 20, 2026
• First Posted (Actual): February 25, 2026

Study Record Updates

• Last Update Posted (Actual): February 25, 2026
• Last Update Submitted That Met QC Criteria: February 20, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: transcutaneous electrical acupoint stimulation; hemodynamic stability; frequency
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Hypotension
• Other Study ID Numbers: XJH-A-20260220

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The de-identified data will be available with reasonable request from Dr. Zhihong Lu at deerlu23@163.com
• IPD Sharing Time Frame: after publication
• IPD Sharing Access Criteria: with request to Dr. Zhihong Lu
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No