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Date of last update: 10/12/2017.

Forum Name: Hematology Topics

Question: Clinical Study Multiple Blood Draw Concern

 noname - Fri Oct 01, 2004 9:36 pm

I signed up for and completed a clincal study and finished it two days ago, Ondansteron HCL generic and Zofran. There were 38 total blood draws, all from the same vein. The vein that was tapped has shrunk and not returned to the size of the opposite arm Are multiple blood draws bad for the veins? Will my vein ever return to the regular size it was before the multiple draws? Are there any serious risks invovled with tapping the vein numerous times over a 24 hour period?

 Dr. Russell M - Sun Oct 03, 2004 2:01 pm

User avatar Hi!

I know that multiple punctures on the same vein can later on lead to stenosis of the lumen or blockage of the vein due to thrombosis. Such thrombosed veins can appear shrinked and dark.


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