The metabolic index of nocturnal hypoxia in patients after lung resection and thoracoplasty

The authors measured urinary uric acid (UA) and creatinine (CR), serum lactate, and CoQ10 prior to retiring at night and on awakening in the morning in 127 patients (PG) after lung resection and thoracoplasty which were done more than 20 years age for treatment of tuberculosis and in 20 controls (NC). delta UA:CR, delta lactate, and delta CoQ10 were calculated respectively as the overnight changes in urinary UA:CR and in serum lactate and CoQ10. delta UA:CR increased in PG (4.0 +/- 43.6%), whereas it decreased in NC (-22.3 +/- 17.7%) (mean +/- SD) (p less than 0.05). Nocturnal hypoxemia suggested from positive balance of delta UA:CR was seen in 37% of PG, but in only 10% of NC. delta UA:CR showed no relationship with delta lactate and delta CoQ10 and also did not correlate with the nadir of arterial oxygen saturation. PG were divided into PG with a positive balance of delta UA:CR (PG-P) and with a negative balance of delta UA:CR (PG-N). The %VC and PaO2 in the PG-P group were lower and PaCO2 was higher than in PG-N, although the difference did not achieve statistical significance.