Hokay, now to consider each body system in a bit more detail. A very important concept here is to always cross reference your findings. Is the heart rate what you would expect given the other parameters? If a cat is in hypovolaemic shock as evidenced by very pale mucous membranes, an absent CRT and very weak femoral pulses, its heart rate should be 220 plus. If it is only 100 why does is have an inappropriately slow heart rate? Could it, for example, be a blocked cat with hyperkalaemia which is slowing the heart rate?