| 摘要 |
A blood aspiration assembly (20) comprises proximal (22), intermediate (50) and distal tubing (24), a reservoir (61) having an adjustable volume, an aspirator receiver (106) and a two-way valve (44). The reservoir (61) can be locked into selected withdrawal and discharge positions. The aspirator receiver (106) is connected between the distal and the intermediate tubing (24,50). The receiver (106) comprises a rigid casing (111) a resilient frusto conical plug (136) and a blood aspiration chamber (110) with a smooth liquid flow surface (116). The valve (44) and reservoir (61) can be operated to draw blood from the patient into the intermediate tube (50) to remove resident fluid from the aspiration chamber (110). A clamp or valve (154) can block intermediate tube (50) flow. The reservoir (61) has a predetermined fluid volume equal to that volume which, when withdrawn into the reservoir from the intermediate tube (50), results in the replacement of essentially all resident fluid in the aspiration chamber (110) and that portion of the apparatus distal to the aspiration chamber by essentially undiluted blood. A needle from a separate syringe is inserted through the plug (136) into the aspirator chamber (110) and a blood sample withdrawn. The tube clamp (154) can be opened and intravenous fluid driven from the reservoir (61) back through the flow channels distal thereto, to force the resident blood back into the patient and fill the assembly with intravenous fluid. |
