Pulmonary embolism shock. Physiologic basis of a bedside screening test

Cardiovascular variables were measured in 43 shock patients in whom pulmonary embolism was at first thought to be the cause. It was found that those patients who were to die of pulmonary embolism could be identified by markedly elevated mean right ventricular pressures and low total blood flows, even though systemic blood pressures and oxygen tensions were maintained near normal levels with vasopressors and oxygen therapy. This finding led to the development of a rapid, safe, bedside screening test for pulmonary embolism shock using flow-guided, intracardiac electrocardiographically monitored, right ventricular manometry. Selective pulmonary angiography can be performed with the same catheter to confirm the diagnosis and to indicate the most expedient operative approach.