Respiratory Training Improves Blood Pressure Regulation in Individuals With Chronic Spinal Cord Injury

Sevda C Aslan; David C Randall; Andrei V Krassioukov; Aaron Phillips; Alexander V Ovechkin

doi:10.1016/j.apmr.2015.11.018

Respiratory Training Improves Blood Pressure Regulation in Individuals With Chronic Spinal Cord Injury

Arch Phys Med Rehabil. 2016 Jun;97(6):964-73. doi: 10.1016/j.apmr.2015.11.018. Epub 2015 Dec 21.

Authors

Sevda C Aslan¹, David C Randall², Andrei V Krassioukov³, Aaron Phillips³, Alexander V Ovechkin⁴

Affiliations

¹ Department of Neurological Surgery, University of Louisville, Louisville, Kentucky.
² Department of Physiology, University of Kentucky, Lexington, Kentucky.
³ Experimental Medicine Program, University of British Columbia, Vancouver, British Columbia, Canada; International Collaboration on Repair Discoveries (ICORD), Department of Medicine, Division of Physical Medicine and Rehabilitation, University of British Columbia, Vancouver, British Columbia, Canada; GF Strong Rehabilitation Centre, Vancouver Coastal Health, Vancouver, British Columbia, Canada.
⁴ Department of Neurological Surgery, University of Louisville, Louisville, Kentucky. Electronic address: alexander.ovechkin@louisville.edu.

Abstract

Objective: To investigate the effects of respiratory motor training (RMT) on pulmonary function and orthostatic stress-mediated cardiovascular and autonomic responses in individuals with chronic spinal cord injury (SCI).

Design: Before-after intervention case-controlled clinical study.

Setting: SCI research center and outpatient rehabilitation unit.

Participants: A sample of (N=21) individuals with chronic SCI ranging from C3 to T2 diagnosed with orthostatic hypotension (OH) (n=11) and healthy, noninjured controls (n=10).

Interventions: A total of 21±2 sessions of pressure threshold inspiratory-expiratory RMT performed 5d/wk during a 1-month period.

Main outcome measures: Standard pulmonary function test: forced vital capacity, forced expiratory volume in one second, maximal inspiratory pressure, maximal expiratory pressure, beat-to-beat arterial blood pressure, heart rate, and respiratory rate were acquired during the orthostatic sit-up stress test before and after the RMT program.

Results: Completion of RMT intervention abolished OH in 7 of 11 individuals. Forced vital capacity, low-frequency component of power spectral density of blood pressure and heart rate oscillations, baroreflex effectiveness, and cross-correlations between blood pressure, heart rate, and respiratory rate during the orthostatic challenge were significantly improved, approaching levels observed in noninjured individuals. These findings indicate increased sympathetic activation and baroreflex effectiveness in association with improved respiratory-cardiovascular interactions in response to the sudden decrease in blood pressure.

Conclusions: Respiratory training increases respiratory capacity and improves orthostatic stress-mediated respiratory, cardiovascular, and autonomic responses, suggesting that this intervention can be an efficacious therapy for managing OH after SCI.

Keywords: Autonomic nervous system; Blood pressure; Breathing exercises; Hypotension, orthostatic; Rehabilitation; Respiration; Spinal cord injuries.

Publication types

Research Support, Non-U.S. Gov't
Research Support, N.I.H., Extramural

MeSH terms

Adult
Autonomic Nervous System / physiopathology
Blood Pressure / physiology
Breathing Exercises / methods*
Chronic Disease
Female
Heart Rate / physiology
Humans
Hypotension, Orthostatic / rehabilitation*
Male
Respiratory Function Tests
Spinal Cord Injuries / physiopathology*
Spinal Cord Injuries / rehabilitation*

Abstract

Publication types

MeSH terms

Grants and funding