Abstract: A blood extraction instrument is provided with an adjustably rotatable connector for a double-ended hollow needle which is offset mounted through the closed end of the cylindrical body of the instrument. The end of the double-ended hollow needle which extends into the instrument pierces a membrane on the end of a blood sample tube which is retained thereon by means of a screw-on cap. The other end of the double-ended hollow needle, which is on the exterior of the instrument, is for insertion into a blood vessel, that is a vein, of a patient. This end is provided with an obliquely cut point. In accordance with the adjustably rotatable connector, the orientation of the flat surface of the needle point which penetrates the patient may be readily adjusted. The instrument is also provided with a retaining tongue formed by a slot in the cylindrical wall of the instrument for providing a retaining means against the back side of the screw-on cap to retain the blood sample tube in the instrument.

Abstract: A blood extraction device includes a hollow, cylindrical receptacle which is open at one end with a double-ended hollow needle at its other end, into which an evacuated blood sample tube is inserted. The blood sample tube is closed by means of a screw-attachment cap, whereby the cap retains a sealing membrane against the blood sample tube in order to close it tightly. A device for evacuation of blood sample tubes is provided. A second needle may be provided at the closed end of the receptacle, via which needle the inserted blood sample tube may be connected with a suction line, which is formed, in one embodiment, by a compressible elastic balloon and a valve.