Central hemodynamics in acute gastrointestinal bleeding.

In 15 patients with acute gastrointestinal bleeding, central hemodynamics were monitored by means of a flow directed thermodilution catheter. Also, the systemic blood pressure, heart rate, blood volume and oxygen saturation in arterial and mixed venous blood were measured. In patients without cardiac insufficiency, the pulmonary artery mean pressure was found to be the hemodynamic parameter giving the most clear and constant evidence of hypovolemia. In patients with left ventricular failure and hypovolemia, the pulmonary artery pressures revealed cardiac insufficiency, and the central venous pressure indicated the degree of hypovolemia. The method has proved useful in observing patients with acute gastrointestinal hemorrhage complicated by cardiac disease, cirrhosis of the liver or the frailty of old age.