NTU Undergraduates' research April 2014 - Biosciences | Page 21

Cardiovascular parameter changes during stimulated valsalva
maneuvers in healthy human subjects
Elizabeth Martin

Abstract
This study focuses on how the heart rate and blood pressure is affected by inducing valsalva maneuvers in 30 healthy subjects.
Also, additional tests were made to identify whether static exercise resulted in valsalva maneuver-like strain. Valsalva maneuver
causes peripheral venous pressure to increase by increasing intrathoracic pressure, therefore, the blood vessels compress
within the chest resulting in baroreceptor activation. Baroreceptor activation is mainly induced by the autonomic nervous
system, in particular the sympathetic nervous system. The baroreflex is responsible for homeostasis within the cardiovascular
system. This study used 30 healthy subjects with systolic pressure 132mmHG ± 2.32 (SEM), diastolic pressure 82mmHG ± 1.72
and pulse (73bpm ± 1.58). Statistical analysis had shown significance between the minimum and maximum heart rates for each
of the phases in comparison to the exercise tests minimum and maximum heart rates. Valsalva ratio and mean arterial pressure
were calculated to compare the two tests further. In summary, the static exercise test with valsalva maneuver vastly increased
the mean heart rate when compared to the normal maneuver test. Also, the static exercise test with normal regular breathing
induced an increase in mean heart rate, which may be due to unconsciously straining when lifting heavy weights.