Abstract: A fluid flow control device for use with an evacuated blood collection container comprises a substantially rigid body. Two needle cannulae are connected to the body with a space therebetween. A resilient, collapsible passage member lies in the space and connects the two cannulae in fluid communication with each other. The passage member contacts the body only at its ends with its central portion positioned to remain free of contact with the body during use. This passage member is accessible to finger grip from at least two different directions to allow an operator of the device to apply pressure with the fingers to control fluid flow through the passage member.Another embodiment of the present invention substantially as described above includes an operable collapsing element connected to the body for collapsing the passage member during use to control fluid flow therethrough.

Abstract: A fluid flow control device for use with an evacuated blood collection container comprises a substantially rigid body. Two needle cannulae are connected to the body with a space therebetween. A resilient, collapsible passage member lies in the space and connects the two cannulae in fluid communication with each other. The passage member contacts the body only at its ends with its central portion positioned to remain free of contact with the body during use. This passage member is accessible to finger grip from at least two different directions to allow an operator of the device to apply pressure with the fingers to control fluid flow through the passage member.Another embodiment of the present invention substantially as described above includes an operable collapsing element connected to the body for collapsing the passage member during use to control fluid flow therethrough.

Abstract: A blood sampling assembly is provided which has a cannula designed for intravenous penetration, a mechanism for applying negative pressure to the cannula, a chamber located between the cannula and the source of negative pressure, a one-way valve positioned within the chamber, and a venting member within the chamber which allows the venting of air as blood enters the chamber, but does not allow the passage of blood. A person drawing blood is enabled to visually determine when a needle is properly inside a vein through transparent walls of the chamber. Spillage of blood is avoided with the present assembly by the resistance of the one-way valve to flow distally from the intravenous cannula.