SK1983
Forum Newbie
Topics: 7
Posts: 7
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in newborns, which of the following mechanisms increases left atrial pressure above right atrial pressure
A) Closure of ductus arteriosus
B)Closure of ductus venosus
C) Decreased pulmonary vascular resistance
D) Decreased Resistance to left ventricular output
E) Increased thickness of right ventricular wall
is it A?
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| fox
Forum Guru
Topics: 70
Posts: 727
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c
___________________
Aim High
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| NE
Forum Guru
Topics: 53
Posts: 504
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It is C
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| bangledoc
Forum Senior
Topics: 8
Posts: 125
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explain pls
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| Ancylostoma
Forum Guru
Topics: 42
Posts: 642
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two things happen in a newborn, we have decrease venous return to the heart because the uterine veins are closed and this lead to less pressure in the r atrium, and second the lungs take there first breath and this causes the blood vessels to open , and more flow will going into the pulmonary system. This blood flow will then via the pulmonay veins go to the left atrium increasing the pressure of the left atrium and cause the closing of the foramen ovale. Oh I forgot , thus the answer is C
Edited by Ancylostoma on 12/27/06 - 01:04 AM
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| brutus25
Forum Junior
Topics: 13
Posts: 62
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Nice explanation Ancylostoma - I really liked it
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