[Skip to Content]
[Skip to Content Landing]
Other Articles
November 17, 1951


JAMA. 1951;147(12):1139. doi:10.1001/jama.1951.73670290008011f

This article is only available in the PDF format. Download the PDF to view the article, as well as its associated figures and tables.


In the course of studies that made it necessary to remove blood samples from the same venipuncture at frequent intervals, we employed a commonly-used type of needle, containing a stylet that occludes its bore. However, in using this device, we frequently found that the bore of the needle was not patent after removal of the stylet.

In an effort to find out the cause of this obstruction, the femoral vein was examined in dogs while the needle was in situ, revealing that a clot occasionally formed at the tip of the needle.

To overcome this obstacle, the new feature of our device permits the stylet to extend about 2 mm. beyond the tip of the needle. The tip of the stylet should be well rounded off. When the stylet is removed, any clot which may have formed at its end would not occlude the tip of the needle. Should a

First Page Preview View Large
First page PDF preview
First page PDF preview