Secondary erythrocytosis due to increased erythropoietin production is a physiologic adaptive response to chronic hypoxemia. Erythrocytosis results in increased shear stress because of hyperviscosity of blood. Hyperviscousity hampers microcirculation, leading to tissue hypoxia. We studied the effect of intraoperative autologous acute normovoluemichemodilution on cerebral and tissue oxygenation.

Twenty patients of adult cyanotic heart disease were enrolled in the study.Patients were allocated into 2 groups with 10 in each. Group 1 underwent autologousnormovoluemichemodilution (ANH). Group 2 patients did not undergo blood donation. The arterial paO2, SaO2 and regional cerebral oximetry (rSO2) from near infrared spectrometry (NIRS) were compared at after induction (T1), after ANH (T2), 30min after initiation of cardiopulmonary bypass (CPB) (T3) and 30 min after CPB (T4).

The paO2 in both groups were 53 ± 3.91 vs 54± 3.41mm Hg (p=0.94) at T1, 64.4± 2.8 vs 55 ± 2.09 mm Hg (p=0.01) at T2, 156.6± 17.76 vs 119.9±14.3 mm Hg (p=0.001) at T3 and 140.5± 10.2 vs 111.3 ± 5.61 mmHg (p=0.001) at T4 time point. The rSO2 values from NIRS were 54.6± 5.06 vs 53.6 ± 5.08 (p=0.94) at T1, 58.1±3.16 vs 53.8± 4.27 (p=0.03) at T2, 81.7± 4.62 vs 65.4±6.27 (p=0.001) at T3 and 76.2± 3.2 vs 70.6±3.23 (p=0.006) at T4.

The study showed that secondary erythrocytosis when exposed tointraoperative ANH improved the arterial and cerebral oxygenation in adult patients with cyanotic heart disease undergoing open heart surgery. Our study corroborates with finding of the problems of hyperviscosity induced by erythrocytosis. (Oechslin E et al, circulation, 2005)

Intraoperative autologous blood donation improves arterial and cerebral oxygenation in adult patients with cyanotic heart disease undergoing open heart surgery.