Breathing Exercises and Auricular Vagus Nerve Stimulation

Phase 2

Completed

• Conditions: Autonomic Nervous System; Breathing Exercises; Auricular Vagus Nerve Stimulation
• Interventions: Device: Vagus nerve stimulation; Behavioral: Breathing exercise

• Registration Number: NCT06531954
• Lead Sponsor: Istanbul Medipol University Hospital

Brief Summary

Introduction: Vagal modulation is achieved directly by transcutaneous auricular vagus nerve stimulation, whereas breathing exercises stimulate arterial baroreceptors. In this study, we aimed to compare these two methods, which have similar effects.

Methods: 88 healthy participants aged 18-35 were randomly divided into breathing exercises (Group BE) and vagus stimulation (Group VNS). Thoracic expansion exercise was performed in the BE group. In the VNS group, biphasic electrical stimulation was applied to both ears with a pulse width of 300 microseconds, frequency of 10 Hz, and 20 minutes. Pulmonary function tests were measured on the first and last day. Heart rate, systolic and diastolic blood pressure, RMSSD, PNN50, LF/HF, LF Power, and HF Power values were measured before and after each of the ten sessions for both groups.

Detailed Description

Not available

Study Timeline

• Study Start: 2021-01-02
• Primary Completion: 2022-01-03
• Study Completion: 2023-03-01
• Status Verified: 2024-07
• Study First Submitted: 2024-07-24
• Study First Submitted QC: 2024-07-31
• Last Update Submitted: 2024-07-31
• Study First Posted: 2024-08-01
• Last Update Posted: 2024-08-01

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 88

Inclusion Criteria

• Healthy individuals between the ages of 18 and 35,
• without orthopedic disability,
• without any chronic disease and regular medication use,
• who had not smoked for the last year,
• who had no problems in reading, writing, or comprehension were included in our study.

Exclusion Criteria

• active or chronic respiratory diseases and communication problems because they may adversely affect pulmonary function testing

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Vagus nerve stimulation group (VNS)	Vagus nerve stimulation	Vagus stimulation was applied bilaterally through the ear. taVNS was performed with the Vagustim device. The stimulation pulse width was 300 microseconds, the frequency was 10 Hz, and it was biphasic with a 20-minute duration. Electrodes were placed on the concha and tragus parts of the ear, and the current was increased through these electrodes until the participant felt pain. When the participant felt pain, the intensity was reduced to a comfortable sensation.
Breathing exercise group (BE)	Breathing exercise	The content of breathing exercises was planned as thoracic expansion exercises. These exercises were applied to the lower, middle, and upper lobes in 3 sets of 3x10 (90 times breathing in one area) and lasted for an average of 20 minutes. These exercises were first taught by the physiotherapist and performed under her supervision. Participants were asked to inhale as deeply as possible into the relevant area, hold their breath for 3 seconds, and then slowly exhale the entire breath.

Primary Outcome Measures

Name	Time	Method
Pulmonary Function. Forced vital capacity (FVC)	pre-intervention, immediately after-intervention	Participants in both groups underwent pulmonary function test evaluation on the first and last day. Since the study was conducted in healthy individuals, it was deemed appropriate to look at the pulmonary function test before and after exertion to see possible changes. Medwelt SP10 spirometer was used for pulmonary function tests in our study. Each individual was measured in a sitting position using a separate mouthpiece.
Autonomic nervous system activity	pre-intervention, immediately after-intervention	Autonomic measurements of each individual participating in the study before and after the intervention were performed with heart rate variability parameters. For this purpose, the Elite HRV device was used. The device has a finger sensor and an application compatible with the phone. Elite HRV application is a software that can synchronize with a personal monitor by collecting peak-to-peak intervals for instant analysis of pulse rate variability (PRV). In addition to all these assessments, blood pressure measurements of the participants were also evaluated using an Omron M2 electronic sphygmomanometer on the right arm.
Pulmonary Function. Forced expiratory volume in the first second (FEV1)	pre-intervention, immediately after-intervention	Participants in both groups underwent pulmonary function test evaluation on the first and last day. Since the study was conducted in healthy individuals, it was deemed appropriate to look at the pulmonary function test before and after exertion to see possible changes. Medwelt SP10 spirometer was used for pulmonary function tests in our study. Each individual was measured in a sitting position using a separate mouthpiece.

Trial Locations

Locations (1)

Mudanya University; 🇹🇷 Bursa, Turkey