Impaired oxygenation and increased hemolysis after cardiopulmonary bypass in patients with glucose-6-phosphate dehydrogenase deficiency

Background The purpose of this study was to determine whether the damaging effects of cardiopulmonary bypass, ischemia, and reperfusion would be more pronounced in patients with glucose-6-phosphate dehydrogenase deficiency undergoing cardiac surgery. Methods Forty-two patients with glucose-6-phosphate dehydrogenase deficiency underwent open heart procedures using cardiopulmonary bypass. This group was matched with a control group of identical size for comparison of operative course and postoperative outcome. The perioperative variables were compared between the two groups using univariate and multivariate analysis. Results The duration of ventilation after the operation was significantly longer in the glucose-6-phosphate dehydrogenase–deficient group (13.7 ± 7.6 hours versus 7.7 ± 2.8 hours; p< 0.0001). Minimal value of arterial oxygen tension was lower in patients with glucose-6-phosphate dehydrogenase deficiency (66 ± 12 mm Hg versus 85 ± 14 mm Hg; p< 0.0001), and more cases of hypoxia (arterial oxygen tension < 60 mm Hg) were found in this group (11 versus 1; p = 0.001). Compared with the control group, patients with glucose-6-phosphate dehydrogenase deficiency had significantly elevated hemolytic indices expressed by bilirubin levels (26 ± 10 mmol/L versus 17 ± 6.7 mmol/L; p< 0.0001) and lactic dehydrogenase levels (970 ± 496 U/L versus 505 ± 195 U/L; p< 0.0001). They also required significantly more blood transfusion perioperatively (1.9 ± 1.4 packed cell units/patient versus 0.8 ± 1.0 packed cell units/patient; p = 0.0001). Conclusions Patients with glucose-6-phosphate dehydrogenase deficiency who are undergoing cardiac surgery may have a more complicated course with a longer ventilation time, more hypoxia, increased hemolysis, and a need for more blood transfusion. Because this difference may be caused by subnormal free radical deactivation, strategies that minimize bypass in general and free radicals specifically may be beneficial.