GB1152133A - Apparatus for Testing the Tendency of Blood to Thrombose - Google Patents

Abstract

1,152,133. Determining thrombosing time; cannulas. E. BOYLE. 12 Oct., 1967 [14 Oct., 1966], No. 46663/67. Headings A5K and A5R. A device for determining the tendency of blood to thrombose i.e. for determining the time between the beginning and completion of the formation of a blood clot in an enclosed passageway, comprises a needle 14 having a handle (16) a removable stylet (22) fitting within the needle and a flexible tube 34 of internal diameter of 0.02 to 0.04 inches and the same as the internal diameter of the needle for attaching to the needle when the stylet is removed. In use, the tube connects the needle to a graduated container 38 having a closure 40 with a vent aperture 33. With the needle inserted in a blood vessel, the volume of blood collected in the container is plotted against time, the rate at which blood thomboses in the tube being determined from the graph produced. The needle handle (16) provides a socket (17) through which the needle extends and which receives the handle (26) of the stylet. Relative rotation of the stylet and needle is prevented by engagament of a tab (29, Fig. 2) on the stylet handle in a slot (20, Fig. 2) in the needle handle. The needle and the stylet are secured to their respective handles by epoxy resin (Sn, Es). For puncturing tissue during insertion of the needle either the needle 14 has a bevelled point (49, Fig. 4) or the stylet 22 has a conical point (28, Fig. 5) the leading ends of the needle and stylet when assembled together forming either a continuous bevelled or conical surface respectively. The tube is connected to the needle by a connector (60, Fig. 9; 80, Fig. 11), which is received in the needle handle socket, or by a flanged end 36.