Effect of different amounts of blood transfusion given at different speeds on left ventricular filling pressure in cases of chronic severe anemia.

Pulmonary capillary 'wedge' pressure (PCWP) was measured before and after transfusion of 1 and 2 units of blood @ 5 and 10 ml/min. in 40 adult cases of chronic severe anemia (CSA). The cases were randomly divided into 4 subgroups of 10 cases each. Following blood transfusion (BT), PCWP increased significantly in all the 4 subgroups (p less than 0.001). The highest rise in PCWP was recorded when 2 units of blood were transfused at a rate of 10 ml/min, and the rise was minimum when 1 unit of blood was transfused @ 5 ml/min. Out of the two variables--speed and amount of BT--the amount was more important. It is, therefore, concluded that administration of 2 units of blood in case of CSA at a rate of 5 or 10 ml/min is not desirable and that transfusion of 1 unit of blood @ 5 ml/min is quite safe.