Higher cerebral oxygen saturation may provide higher urinary output during continuous regional cerebral perfusion

OBJECTIVE: We examined the hypothesis that higher cerebral oxygen saturation (rSO(2)) during RCP is correlated with urinary output. METHODS: Between December 2002 and August 2006, 12 patients aged 3 to 61 days and weighing 2.6 to 3.4 kg underwent aortic arch repair with RCP. Urinary output and rSO(2 )were analyzed retrospectively. Data were assigned to either of 2 groups according to their corresponding rSO(2): Group A (rSO(2 )≦ 75%) and Group B (rSO(2 )< 75%). RESULTS: Seven and 5 patients were assigned to Group A and Group B, respectively. Group A was characterized by mean radial arterial pressure (37.9 ± 9.6 vs 45.8 ± 7.8 mmHg; P = 0.14) and femoral arterial pressure (6.7 ± 6.1 vs 20.8 ± 14.6 mmHg; P = 0.09) compared to Group B. However, higher urinary output during CPB (1.03 ± 1.18 vs 0.10 ± 0.15 ml·kg(-1)·h(-1); P = 0.03). Furthermore our results indicate that a higher dose of Chlorpromazine was used in Group A (2.9 ± 1.4 vs 1.7 ± 1.0 mg/kg; P = 0.03). CONCLUSION: Higher cerebral oxygenation may provide higher urinary output due to higher renal blood flow through collateral circulation.