From: email@example.com(Steven B. Harris)
Subject: Re: i.v. injection question for m.d.
Date: 10 Aug 1998 04:34:36 GMT
In <firstname.lastname@example.org> email@example.com writes:
>On Fri, 07 Aug 1998 07:27:44 GMT, firstname.lastname@example.org wrote:
>>How much air is dangerous to enter the bloodstream via i.v. injection ?
>>A nurse told me that anything less than 1mL(1cc) is harmless- is this
>>accurate ? Any helpful responses are appreciated.
>There is really no reason at all for a correctly performed intravenous
>injection to contain even a tiny air bubble.
Nevertheless, a few cc's of air in your venous system (a standard IV
line) would be harmless, unless you were unlucky enough to have a
congenital atrial or ventricular septal defect, allowing bubbles to
bypass the lungs. Lungs are a great filter, and they trap bubbles and
clots before they get to the brain or other places where they do damage
by interfering with blood supply.
Failing a heart defect, the amount of air necessary to kill a normal
person varies a great deal depending on position, chance, rapidity of
injection, etc. It's more than several hundred cc's. Generally, you
need enough to create a giant bubble in the right heart, large enough
to interfere with liquid pumping ("vapor lock").
A few patients have probably seen a little bubble go down their IV
line and into them, and had heart attacks waiting for the heart attack!
Steve Harris, M.D.