Impact of venous catheters on packed red blood cells.

This study was designed to test the hypothesis that there would be increased hemolysis, as indicated by an increase in plasma free hemoglobin and potassium, when packed cells were infused through small gauge percutaneous catheters (24 and 28 g, PC) compared with short catheters (24 g; SC). We were unable to study the 28 g PC because after 1 hour, at a flow rate of 10 ml/hr, only 2.4 ml packed cells were infused. There was a significant increase in plasma free hemoglobin when pre- and postinfusion values were compared (SC, p = 0.005; PC, p = 0.009), but a statistically significant increase in potassium only for the SC (p = 0.008). There were no significant differences between the catheters for either potassium or free hemoglobin. For either catheter the quantity of free hemoglobin transfused could potentially cause a significant rise in serum bilirubin and hemoglobinuria.