The effect of haemorrhage and bone fracture on bone marrow circulation.

Blood flow was measured in the bone marrow and trabecular bone of the dog using 133Xe and hydrogen clearance technique. Estimated from hydrogen wash-out curves, flow in the marrow of the femoral diaphysis was 0.207 ml.min(-1).g(-1), in the marrow of the humerus 0.123ml.min(-1).g(-1) and in the trabecular bone of femoral metaphysis 0.173ml.min(-1).g(-1). Haemorrhagic hypotension and fracture reduced the medullary flow. After haemorrhage an exponential relationship was found between blood pressure and effective bone marrow and muscle blood flow. The correlation between systemic arterial and intramedullary pressures was found to be exponential and between intramedullary pressure and flow linear.