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Updated: Aug 12, 2026
Quantitative Autonomic Testing
Published on: July 19, 2011
Effect of position on cardiovascular response during the Valsalva maneuver
1School of Nursing, University of Michigan, Ann Arbor.
Abstract:
Sudden cardiac death (SCD) has frequently been associated with the Valsalva maneuver (VM), which is characterized by sudden intense changes in systolic blood pressure (SBP) and heart rate (HR). The purpose of this study was to examine the effect of manipulating body position on the intensity of SBP and HR changes during the VM. Thirty-two men and 32 women (35-55 years) without a history or signs of cardiovascular disease (CVD) were studied. Subjects produced a VM of 40 mmHg for 10 seconds in each of five randomly assigned bed (flat, sidelying, 30 degrees elevated, 70 degrees elevated) and chair positions. Age covaried with SBP and HR responses to the VM. When age relationships were factored out, the most intense changes in SBP during the VM occurred in the 30 degrees and 70 degrees elevated and chair positions. Persons with a history of atherosclerotic CVD, on bedrest, should be positioned with head of the bed flat to reduce cardiovascular risks associated with the VM.
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