[Perioperative acute kidney injury]. / Perioperative akute Nierenschädigung.

BACKGROUND: Acute kidney injury (AKI) is a frequent complication in the perioperative period and is associated with a high morbidity and mortality. AKI is an independent risk factor for adverse outcome. The Kidney Disease: Improving Global Outcome (KDIGO) guidelines define AKI based on increases in serum creatinine and/or urinary output. Since there is no causal therapy available, early detection and timely implementation of preventive measures are of particular importance. OBJECTIVE: This article gives an overview of the disease picture of perioperative AKI. The recommendations on diagnostics, prevention and treatment are presented. METHODS: The available evidence is summarized based on the currently available literature. RESULTS: New renal biomarkers demonstrate kidney stress and are able to make an early prediction of the development of AKI. The implementation of the KDIGO bundles (discontinuation of all nephrotoxic medications, optimization of the volume status and perfusion pressure, consideration of an extended functional hemodynamic monitoring, close monitoring of serum creatinine concentration and urine output, avoidance of hyperglycemia and consideration of alternatives to radiocontrast agents) and remote ischemic preconditioning have shown a significant reduction in the incidence of AKI in high-risk patients. CONCLUSION: For timely diagnosis and prevention of AKI the recommendations for action of the KDIGO guidelines should be implemented. High-risk patients should be detected early in the perioperative period in order to be able to initiate preemptive strategies in a timely manner.

[Renal replacement therapy in acute kidney injury : From the indications to cessation]. / Nierenersatzverfahren bei akuter Nierenschädigung : Von der Indikation bis zur Beendigung.

BACKGROUND: The incidence of acute kidney injury (AKI) has increased over the last decades. Renal replacement therapy (RRT) is increasingly being used. The Kidney Disease: Improving Global Outcomes (KDIGO) guidelines define AKI by serum creatinine (SCr) elevation and decrease in urinary output (UO) and suggest prevention strategies and recommendations on the management of RRT. Treatment options are limited and RRT remains the gold standard as supportive treatment but implies a substantial escalation of treatment. With respect to the indications and management of RRT, there are only a few evidence-based recommendations. OBJECTIVE: This review summarizes the clinical relevance of AKI and presents the most important aspects on the indications and implementation of RRT. MATERIAL AND METHODS: The available evidence is summarized based on the current literature. RESULTS: Implementation of the KDIGO bundles to prevent AKI in high-risk patients reduces the incidence of AKI. In the absence of absolute indications, the evidence-based recommendations on when to initiate RRT are limited and controversial. Intermittent hemodialysis (IHD) and continuous renal replacement therapy (CRRT) procedures can be considered as complementary therapeutic strategies. The CRRT is recommended in hemodynamically unstable patients. Regional citrate anticoagulation is the recommended anticoagulation in CRRT. The optimal effluent dose is effectively 20-25 ml/kg body weight and hour. Spontaneous diuresis is a best predictor of successful cessation of RRT. CONCLUSION: Risk identification and prevention of AKI are essential. In the absence of absolute indications, initiation and accomplishment of RRT should be patient-adapted and carried out in the clinical context. Newly developed biomarkers could be helpful in the future for a better estimation of the prognosis and for a more precise definition of therapeutic strategies of RRT.