The capnograph, a reliable non-invasive monitor for the detection of pulmonary embolism of various origin.

The wash-out curve in the capnogram is known to be a sign of pulmonary air embolism. This characteristic pattern is also seen in the case of pulmonary embolism of other nature. Capnographic recordings were studied retrospectively and 22 wash-out curves were found. The quantitative change in end-tidal carbon dioxide concentration was compared with the change in other, circulatory parameters known to change in the case of pulmonary air embolism. There proved to be a quantitative correlation between the decrease in end-tidal carbon dioxide concentration and the change in pulmonary artery pressure, central venous pressure and mean arterial pressure. The capnograph showed to be a reliable monitor for the detection of pulmonary embolism of various origin just like pulmonary artery pressure monitoring is. In cases with concomitant Doppler ultrasound detection, the capnograph showed to be a more reliable monitor for the detection of pulmonary air embolism as is the Doppler ultrasound device.