Skin Petechiæ and Fat Embolism

In a prospective study, skin petechiœ were found in 20 out of 119 patients with fractures. Seven patients with widespread skin petechiœ had elevated respiratory rates and hypoxœmia, and five also had cerebral abnormalities. In contrast, the 13 patients with petechiœ confined to the axillœ were well and were not hypoxœmic. The electron microscopic findings suggest that the extravascular plasma, red cells and fat globules which formed the petechiœ escaped through gaps between the endothelial cells of postcapillary venules and following rupture of fat‐filled capillaries. It is probable that vasoactive amines, thrombocytopenia and hypoxœmia were important factors in the production of these endothelial gaps.