Association between pulmonary dysfunction and reduced red cell deformability following cardiopulmonary bypass.

Fifty-six patients undergoing open-heart surgery were monitored for red cell trauma during cardiopulmonary bypass (CPB), using a standard red cell microfiltration method. The average red cell deformability was reduced by 38%. Respirator time was shorter in the patients with lesser degrees of red cell trauma, and vice versa. After extubation, the tendency to hypercapnia was greatest in the patients with most red cell trauma during CPB. Hypoxic tendencies in the first 24 postextubation hours were comparably distributed among all levels of red cell trauma.