Renal dysfunction according to the ADQI-RIFLE system and clinical practice patterns after cardiac surgery in Germany.

Aim: The aim of this study was to determine the incidence of renal dysfunction according to the Acute-Dialysis-Quality Initiative-(ADQI)-RIFLE grading system in cardiac surgery in Germany in 2003 and to determine if variations in the incidence of renal dysfunction are related to clinical practice patterns.

Design: prospective cohort analysis and practice pattern survey.

Measurements: 81 hospitals were requested to report prospectively sampled quality-management-data on patient load, case mix, aortic-cross-clamp-time, baseline and maximal plasma creatinine (CreaP), new-onset-renal-replacement-therapy, and clinical practice concerning the use of fluids, inotropic and vasopressor drugs, and diuretics. Fifty-one (63%) centers answered the survey. Twenty-six centers (32%)(representative for 29 623 patients(reported creatinine data.

Results: The incidence of a 50%, 100%, or 150% increase in plasma creatinine (graded as risk, injury, and failure according to the ADQI-RIFLE-system) were 9% (2-40%), 5% (0.8-30%), and 2% (0.6-33%), respectively, overall 15.4% (3.1-75%). The incidence of new-onset renal-replacement-therapy was 4.5% (0.6-24%). Centers with a low incidence of renal dysfunction 8.7% (3.1-15.4%)differed from those with a high incidence 51% (15.7-75%)by being more liberal with fluids, not preferring dopamine in ''renal'' or inotropic doses, and preferring noradrenaline as a vasopressor (all: P<0.05), but not by case mix, frequency of urgent or emergency cases, and the use of loop diuretics.

Conclusions: Renal dysfunction is a frequent complication following cardiac surgery in many German heart centers. The variance between centers may not be explained by patient heterogeneity and may be related to different strategies regarding fluid therapy and the use of inotropes and vasopressors.