Pressure changes: Neck veins distend when we lie with our head lower than our heart or when we strain. With straining, the pressure within the chest increases and the blood flow through the neck veins decrease resulting in them enlarging.When straining is stopped, the pressure in the chest decreases and flow continues through the neck veins so they become less engorged.
Answered 12/10/2013
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A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
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