Fat embolism syndrome and pulmonary microvascular cytology.

Pulmonary microvascular cytology consists of analysis of capillary blood sampled while a Swan-Ganz catheter is in the wedge position. This technique has proved to be useful in the diagnosis of lymphangitic spread of carcinoma in the lungs and there are case reports of their use in amniotic fluid embolism. Its usefulness in diagnosing fat embolism syndrome has been shown only rarely. We report a new case in which pulmonary microvascular cytologic study allowed a definite diagnosis of fat embolism syndrome. We suggest obtaining routinely samples of capillary blood when a pulmonary catheter is in place and fat embolism is suspected on a clinical basis.