biophysicianai

10+ Year Member
5+ Year Member
Nov 1, 2008
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Medical Student
just a guess, but is it a combo of gas rising + a lack of venous valves in relevant veins?
 
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SillyStudent
Nov 23, 2013
6
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Status
MD/PhD Student
Thanks to the keyword gravity I found this in google books.

With the operative site elevated compared with the heart, gravity causes a negative venous gradient between the operative site and the right atrium; this creates a potential for an air embolism if a venous sinus is opened.

From
Alexander's Care of the Patient in Surgery

Thanks, question solved.