Cardiopulmonary bypass without preoperative exchange transfusion in sicklers

The effect of hypothermic cardiopulmonary bypass techniques on the sickling process was evaluated in patients with sickle cell hemoglobin. It was presumed that intraoperative hemolysis, as identified by hemoglobinuria, reflected increased sickling. Data of 43 patients with sickle cell traits and 2 with sickle cell disease, who were operated on under cardiopulmonary bypass and cold cardioplegic arrest in a tertiary center from the beginning of 1995 to the end of 2004, were retrospectively analyzed. A mean nasal temperature of 30.8 degrees C +/- 2.1 degrees C was achieved. Three patients with sickle cell trait developed intraoperative hemoglobinuria, albeit with normal surrogate values for hemolysis. However, they had significantly lower mean hemoglobin levels during cardiopulmonary bypass compared to those sickle cell patients who did not exhibit hemoglobinuria (hemoglobin, 6.0 +/- 0.2 vs. 7.4 +/- 0.9 g x dL(-1), p < 0.01). Total drainage and blood transfusion requirements in patients with normal and sickle cell hemoglobin were similar. It was concluded that hypothermic cardiopulmonary bypass with cold cardioplegia is safe in sickle cell patients. Maintenance of adequate hemoglobin levels during cardiopulmonary bypass may be important to avoid triggering a sickling process.