[Hemodynamic and respiratory changes in operations of the esophagus by unilateral ventilation].

One-lung ventilation offers optimal operating conditions during intrathoracic surgery. Hemodynamic and respiratory changes were measured in 9 patients. Cardiac output was unchanged, arterial pO2 decreased and venous admixture increased markedly. The increase in mean pulmonary artery pressure and pulmonary vascular resistance are signs for hypoxic pulmonary vasoconstriction in the unventilated lung. In spite of an inspiratory oxygen concentration of 66% oxygen availability was decreased by about 20%. Anaesthesia and related procedures should not interfere with pulmonary autoregulation. Complete monitoring is necessary to safely assess oxygenation of the patient.