Myocardial Depression Following Citrated Blood Transfusion

Fifteen hypovolemic dogs and 16 hypovolemic patients (following cardiopulmonary bypass) were studied, while heparinized whole blood and citrated whole blood were administered alternately in equal volumes at equal rates. Heparinized blood quickly restored cardiac output and arterial pressure with physiologic elevations in left atrial pressure (LAP) and central venous pressure (CVP) while cardiac work showed a normal function curve. In contrast, citrated blood, administered at the same rate, often failed to restore and frequently depressed cardiac output and arterial pressure, caused pathologic elevations in LAP and resulted in abnormal (heart failure) function curves. The CVP was an unreliable and often misleading guide to volume therapy. When citrated blood was effective in raising cardiac output and arterial pressure, larger volumes were required than if noncitrated blood was employed. The administration of calcium chloride before or after transfusion did not always prevent citrate intoxication, although simultaneous administration was always effective.