NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Enhanced carotid-cardiac baroreflex response and elimination of orthostatic hypotension 24 hours after acute exercise in paraplegicsTo test the hypothesis that an acute bout of maximal exercise can ameliorate orthostatic hypotension consequent to prolonged wheelchair confinement, we evaluated heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure responses during 15 minutes of 70 degrees head-up tilt (HUT) in 10 paraplegic subjects 24 hours after arm crank exercise designed to elicit maximal effort, and during a control (no exercise) conditions. Additionally, the carotid baroreceptor stimulus-cardiac response relationship was determined by measurement of R-R interval during external application of graded pressures to the carotid sinuses. One week separated the treatment conditions. The maximum slope of the carotid-cardiac baroreflex response was increased (p = 0.049) by exercise (6.2 +/- 1.7 msec/mmHg) compared to control (3.3 +/- 0.6). During control HUT, HR increased from 61 +/- 1 to 90 +/- 7 bpm (p = 0.001) while SBP decreased from 118 +/- 5 to 106 +/- 9 mmHg (p = 0.025). During HUT 24 hours after exercise, HR increased from 60 +/- 2 to 90 +/- 4 bpm (p = 0.001), but the reduction in SBP was essentially eliminated (116 +/- 5 to 113 +/- 5 mmHg).
Document ID
19930048784
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Engelke, K. A.
(NASA John F. Kennedy Space Center Cocoa Beach, FL, United States)
Shea, J. D.
(NASA John F. Kennedy Space Center Cocoa Beach, FL, United States)
Doerr, D. F.
(NASA John F. Kennedy Space Center Cocoa Beach, FL, United States)
Convertino, V. A.
(NASA Kennedy Space Center Cocoa Beach, FL, United States)
Date Acquired
August 16, 2013
Publication Date
December 1, 1992
Publication Information
Publication: Paraplegia
Volume: 30
Issue: 12
ISSN: 0031-1758
Subject Category
Aerospace Medicine
Accession Number
93A32781
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available