Pulmonary embolism presenting as adult respiratory distress syndrome-support for a hypothesis.

Introduction Adult respiratory distress syndrome (ARDS), or non-cardiogenic pulmonary oedema, is known to complicate classic pulmonary embolism (Robin, Cross and Zelis, 1973). It has been well documented in animal experiments (Singer et al., 1957; Swenson, Lamas and Ring, 1965; Parmley, North and Ott, 1962) but is rare in man (Meth et al., 1975). A number of mechanisms have been proposed including the notion that major occlusions of the pulmonary vasculature may result in pulmonary hypertension with transmission of the high pulmonary arterial pressure to unobstructed portions of the pulmonary capillary bed (Robin et al., 1973). Nevertheless, this has not been demonstrated in man and the present case is presented in support of this hypothesis. The patient described here had angiographically documented pulmonary emboli and developed pulmonary oedema confined to unobstructed segments and in the presence of a normal pulmonary capillary 'wedge' pressure.