Pathophysiology, prophylaxis, and treatment of cardiac surgery-associated kidney injury. Position of the working group renal failure of the collaborative group Cardiothoracic Intensive Care of the DGAI and DGTHG on the consensus statement of the Acute Dialysis Quality Initiative

Few complications in cardiac surgery have such a negative impact on patient prognosis as perioperative renal dysfunction, now called cardiac surgery-associated acute kidney injury (CSA-AKI): even the slightest increases in postoperative plasma creatinine are associated with a relevant worsening of prognosis. The present manuscript is an updated and extended summary of the recently published consensus statement of the Acute Dialysis Quality Initiative (ADQI) on CSA-AKI intended to give an overview of the epidemiological and pathophysiological mechanisms of this complication and interventions aimed to prevent and treat it. At present, no pharmacological approach has been shown to be effective in large scale prospective randomized trials to prevent CSA-AKI. In contrast, the pathophysiological mechanisms behind this complication are highly suggestive that many of the factors associated with CSA-AKI may be modified into a positive direction by implementing an interdisciplinary approach with the clinical goals: prevention of endogeneous and exogeneous nephrotoxins, maintenance of normoglycemia, adequate systemic perfusion pressure and flow, and euvolemia, adjusting systemic oxygen delivery to demand, and by avoidance of embolic complications. Thus, CSA-AKI may - at least in part - be reflective of a suboptimal clinical management that can be optimized according to the individual center. The therapy of established CSA-AKI does not differ from treatment of acute renal failure of other etiology. However, published data suggest that the early institution of renal replacement therapy, i.e., before uremic complications have occurred, may be associated with an improved prognosis. The use of loop diuretics is not beneficial and may be even harmful, and renal dose dopamine does not prevent CSA-AKI or constitute a reasonable treatment of this complication.