Slow Yogic-Derived Breathing and Respiration and Cardiovascular Variability in Spinal Cord Injury Patients

Study Overview
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Brief Summary
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This research will aid in understanding of slow-breathing and its effect on heart rate and blood pressure in people with a spinal cord injury (SCI). This research will investigate if traditional 'yogic' breathing exercises can be performed by subjects with SCI and its influence on the cardiovascular system.

Detailed Description
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The relationship between respiratory patterns and cardiovascular variability in healthy persons has been previously studied. However, the impact of SCI on the interrelationships between the respiratory and cardiovascular systems remains relatively unstudied. The loss of autonomic control in SCI may mean that slow breathing has profound effects on cardiovascular variability. Hence, those with SCI may represent a population that could benefit from the potential physiologic effects of numerous yogic-based breathing patterns that can be applied anywhere any time. Hence, it is important to determine if slower breathing patterns can shift the cardiovascular control pattern to-wards important healthful effects. This physiological study will compare the effects of uncontrolled breathing and traditional yogic slow-breathing practices on cardiovascular variability in SCI patients.

Official Title
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Effect of Slow Breathing and Yogic-Derived Breathing on Respiration and Cardiovascular Variability in Spinal Cord Injury Patients

Conditions
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Spinal Cord Injuries, Slow Breathing

Intervention / Treatment
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* Behavioral: Slow Breathing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age: 18-60 years old Wheelchair user Medically stable & able to follow directions Body mass index (18.5 - 35 kg/m2) Exclusion Criteria: BP >140/90 mmHg Current use of cardioactive medications (except medication to support blood pressure) Current tobacco use Significant arrhythmia Coronary artery disease Diabetes Renal Disease Cancer Epilepsy or other neurological diseases

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Intervention Model: Single Group Assignment
Interventional Model Description: This study will be a small prospective cohort (N= 20) study with a one-time unblinded intervention of 4 differing breathing techniques/ratios compared to spontaneous breathing. Patients will receive instruction on D1 and on D7 lasting about 45 minutes and a diary for self-practice. On D14 the participant will be asked to sequentially perform the directed breathing frequencies and ratios. The lab visit will last approximately 1.5 hours, during which beat-by-beat cardiovascular variables and breath-by-breath respiratory variables will be recorded. The total in-person time commitment ( 4 hours) over the 14 days.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Spinal Cord Injury Subjects<br>20 medically stable male and female subjects between 18 and 60 years old, BMI between 18.5-35 kg/m2, with a history of SCI and who use a wheelchair were included. Participants that did not speak English or with a history of renal, neurological, or coronary artery disease, cancer, diabetes, significant arrhythmia smoking, or using cardioactive medications were excluded. | Behavioral: Slow Breathing<br>* On two separate visits (on Day 1 and between Day 7 and 9 of their self-practice) the subject will be coached on yoga breathing techniques. The breathing techniques will be varied in: frequency (between 0.25 and 0.1 Hz) Inspiratory:Expiratory (I:E) ratio or 'Duty Cycle' with and without ujjayi (yogic throat restriction) with and without inspiratory/expiratory breath holding At the end of the first coaching visit the subject will be given a diary to record their own practice of the breathing techniques they were coached on.<br>* Other names: Yogic-Derived Breathing;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart Rate Variability | R-R interval on a 5 lead Electrocardiogram (EKG) | 1,5 hour during Slow-breathing | 
| beat-by-beat arterial pressure | blood pressure fluctuations via Finometer and Dinamap blood pressure cuff | 1,5 hour during Slow-breathing | 
| beat-by-beat limb blood flow | brachial blood flow via doppler | 1,5 hour during Slow-breathing | 
| peripheral capillary oxygen saturation (SpO2) | blood oxygen saturation via pulse oximetry | 1,5 hour during Slow-breathing | 
| respiratory excursions | Measuring belly and chest depth of inspiration and expiration | 1,5 hour during Slow-breathing | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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resonance, yogic, pranayama, spinal cord injury