System of measuring the corpuscular content of a fluid, e.g. blood

摘要

For measuring the corpuscular content of a fluid, in particular blood hematocrit, a system includes a catheter (101) whose tip (102) is inserted into a patient's bloodstream; the catheter includes one or more transmitting optical fibres (nn) for conducting light from a light source (DS1,DS2) to the tip and one or more receiving optical fibres (pp, oo) for receiving the light reflected by the corpuscles and transmitting it to a detector (244a, 244b, 244c) (not shown). The optical fibres together define two optical paths (although the paths can share a common optical fibre, e.g. fibre nn) and the relationship (e.g. the separation) between the transmitting optical fibre and the receiving optical fibre of one path is different to that of the other path and the system can include means to calculate blood hematocrit from the difference between the signals along the two paths.