Regional lung function following hip arthroplasty and preoperative normovolemic hemodilution.

The effect of preoperative normovolemic hemodilution with dextran 70 as dilutional agent on postoperative regional lung function was evaluated in patients undergoing hip arthroplasty in the lateral decubitus position. The major part of the surgical blood loss of these patients was replaced with the received autologous blood. The results obtained were compared to changes in a group of patients in whom the operative bleeding was replaced with bank blood. Regional lung function, as studied with Xe133 radiospirometry, is not negatively influenced by the hemodilution technique. In both groups a reduction in perfusion, ventilation and volume of ventilated alveoli was revealed postoperatively in the lung that was dependent during surgery, probably caused by impaired ventilation of this lung and peroperatively induced microembolism. A more rapid normalization was found in the preoperatively hemodiluted patients. The reduced volume of bank blood transfused to these patients and/or a protective effect of the preoperatively infused dextran on the microembolism evoked by the surgical trauma might explain this difference between the groups studied.