Hemodynamic observation in relation to extensive surgical treatment of patients with increased operative risk.

In 25 patients, considered high surgical risks according to clinical criteria, systemic and pulmonary hemodynamic parameters were monitored using a flow-directed pulmonary arterial thermodilution catheter before, during and after major vascular surgery. During and after the operation, hemodynamic complications were observed in 13 patients. The following conditions were dealt with: hypovolemia, increased systemic vascular resistance, and left ventricular failure in hypervolemia and in normovolemia. Tachy-arrhythmias seen in six of the patients were associated with left ventricular failure, hypovolemia or normal hemodynamics. Operation for renovascular hypertension and thoracolaparotomy carried the highest risk. Two of the patients died from primarily surgical complications.