Acute hemodynamic effects of increasing hemoglobin concentration in children with a right to left ventricular shunt and relative anemia.

ABSTRACT

The short-term effects of increasing hemoglobin concentration were evaluated at cardiac catheterization in seven children (aged 0.3 to 7.5 years) with a right to left ventricular shunt and relative anemia. Diagnoses were tetralogy of Fallot in six and L-transposition of the great vessels with ventricular septal defect and pulmonary stenosis in one. Before and 20 minutes after isovolumic partial exchange transfusion with 20 ml/kg packed red cells, the following variables were measured hemoglobin, partial pressure of oxygen (PO2), oxygen consumption, oxygen saturation and pressure in the aorta, superior vena cava and right and left atria. After partial exchange transfusion, hemoglobin increased from 13.7 +/- 0.5 to 16.4 +/- 0.4 g/100 ml (p less than 0.001, mean +/- SEM). Aortic PO2 increased from 55.0 +/- 3.5 to 62.0 +/- 4.1 mm Hg (p less than 0.01) and aortic oxygen saturation increased from 84.3 +/- 2.3 to 90.9 +/- 1.3% (p less than 0.002). Effective pulmonary blood flow increased by 17% from 2.72 +/- 0.10 to 3.17 +/- 0.10 liters/min per m2 (p less than 0.01), and right to left shunt decreased by 59% from 1.44 +/- 0.29 to 0.59 +/- 0.10 liters/min per m2 (p less than 0.01). Systemic oxygen transport increased from 658 +/- 48 to 738 +/- 46 ml/min per m2 (p less than 0.002). After partial exchange transfusion, systemic vascular resistance increased from 15.9 +/- 1.1 to 20.0 +/- 1.4 units (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)