Renal tubular injury during cardiopulmonary bypass as assessed by urinary release of N-acetyl-ss-D-glucosaminidase

• BackgroundAcute kidney injury (AKI) is a common complication with a major impact on morbidity and mortality after cardiac surgery with cardiopulmonary bypass (CPB). The aim of the present study was to perform a detailed analysis on the release of the tubular injury biomarker N-acetyl-b-D-glucosaminidase (NAG) during and early after CPB and to describe independent predictors of maximal tubular injury. We hypothesized that renal tubular injury occurs early after the onset of CPB. MethodsIn this prospective observational study, we included 61 patients undergoing open cardiac surgery with an expected CPB duration exceeding 60min. The urinary NAG levels were measured at 30min intervals during CPB, as well as early (30min) after CPB and post-operatively. Independent predictors of tubular injury were identified using an Interquantile multivariate regression model. ResultsAlready 30min after the onset of CPB, NAG excretion was significantly increased (P<0.001), followed by a sixfold peak increase after discontinuation of CPB (P<0.001). In the multivariable regression model, CPB duration (P<0.05) and the degree of rewarming during CPB (P<0.05), were independent predictors of peak NAG excretion. ConclusionIn cardiac surgery, a renal tubular cell injury is seen early after onset of CPB with a peak biomarker increase early after end of CPB. The magnitude of this tubular injury is independently related to CPB duration and the degree of rewarming. Efforts made to decrease the CPB duration and to avoid hypothermia and the need for rewarming may decrease the risk for tubular injury.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine (hsv//eng)

Keyword

acute kidney injury

cardiac-surgery

inflammatory response

creatinine

values

minimal changes

failure

association

disease

plasma

risk

Publication and Content Type

ref (subject category)

art (subject category)