18) THE VALSALVA MANOUVER IS ASSOCIATED WITH

[Editor]

a) a rise in the CVP
b) a reduction in SVR
c) a tachycardia
d) a reduction in blood pressure
e) increased blood volume in the pulmonary circulation

[Editor]

TFTTF

The valsalva maneuver is the expiration against a closed glottis. This produces many physiological parameter changes. These occur in a particular order involving 4 phases.
On initiation of the valsalva maneuver the intra thoracic pressure rises. This causes an increase in blood pressure with a baroreceptor mediated drop in heart rate. The continued increase in intra thoracic pressure prevents venous return and hence causes a reduction in preload. This results in a drop in blood pressure with a baroreceptor mediated response. This time it causes an increase in CNS sympathetic output resulting in a tachycardia and an increased systemic vascular resistance .The blood pressure is returned to its normal levels .On release of the valsalva maneuver the impedance to venous return is removed resulting in a greater preload, hence cardiac output and blood pressure increase. A reflex bradycardia occurs once again mediated by the baroreceptor pathway.