Factors that confound the prediction of renal medullary oxygenation and risk of acute kidney injury from measurement of bladder urine oxygen tension

Abstract

uPO₂ provides a robust estimate of mPO₂ , but this relationship is confounded by the simultaneous presence of systemic hyperoxia and low urine flow. Urine flow increases and uPO₂ decreases during CPB. Thus, CPB is probably the best time to use uPO₂ to detect renal medullary hypoxia and risk of post-operative AKI.