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.