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Purpose of review Acute kidney injury (AKI) is underestimated but common in the perioperative setting. Although the association of this syndrome with an increased morbidity and mortality has been well established, little progress has been made in the diagnosis or prevention of AKI in recent years. This is partly due to the late detection of AKI by conventional criteria based of functional biomarkers, serum creatinine, and urine output. In addition, conceptually AKI is now recognized as being part of a continuum, in which preventive intervention is time critical. This review will summarize the current best available evidence and explain why timely perioperative management does have impact on the development of AKI and overall outcomes for patients. Recent findings Damage biomarkers can reliably identify AKI earlier than conventional functional biomarkers, facilitating more timely preventive intervention. Although the interventions published in the Kidney Disease: Improving Global Outcomes guideline are all important, the most relevant preventive options perioperatively include maintenance of adequate volume status and perfusion pressure, and the focus on balanced crystalloid solutions as maintenance fluid. Summary AKI is a time critical syndrome that requires timely detection and damage biomarkers can help to adjust the perioperative management to prevent further injury.

Purpose of review Surgery, invasive procedures and anesthesia itself may induce an inflammatory response in the patient. This represents an evolutionary inherited and conserved response of the host to environmental stimuli and may lead to both beneficial and potentially harmful effects. This review highlights the mechanisms of anesthesia-induced and perioperative immune modulation. Recent findings The innate and adaptive immune system serve the host in protection against invading pathogens. Yet, an inflammatory immune response may also be induced by different noninfectious stimuli, for example invasive perioperative procedures and the surgical trauma itself. These stimuli may lead to the activation of the immune system with the consequence of perturbation of cell, tissue of even organ functions in cases of an overshooting immune response. Several perioperative factors have been identified that modulate the immune response, for example different anesthetic drugs and surgical tissue injury, but their impact on immune system modulation may also vary with respect to the procedural context and include both pro-inflammatory and anti-inflammatory effects. Summary The current review will highlight the current knowledge on the perioperative anesthesia-induced and surgery-induced modulation of the immune response and also address possible intervention strategies for the development of future therapeutic approaches.

Purpose of review In an attempt to make cardiovascular monitoring less invasive and more effective, transesophageal echocardiography is progressively being used in critically ill patients suffering from hemodynamic instability. This review analyses the capacity of transesophageal echocardiography to fully replace the pulmonary artery catheter in the management of hemodynamic impairment, as transesophageal echocardiography similarly allows for the measurement of central venous pressure, pulmonary arterial pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance, stroke volume and cardiac output, and systemic vascular resistance. Recent findings Recently, the accuracy and clinical applicability of transthoracic echocardiography to establish the entire hemodynamic profile in patients with decompensated heart failure has convincingly been demonstrated. Because many principles are similar in transthoracic and transesophageal echocardiography, it has been hypothesized that the latter modality is also qualified to quantitatively determine intracardiac hemodynamics, including pressure and flow. Summary Transesophageal echocardiography has the potential to offer a noninvasive, valid alternative to Swan-Ganz catheters in the hemodynamic assessment of patients in the perioperative period.

Purpose of review Acute kidney injury (AKI) is a common and serious complication that significantly increases morbidity, mortality, and cost of care after surgery. In this article, we review recent studies that deal with strategies for renal protection and the prevention of AKI after surgery. Recent findings A prerequisite for any prophylactic intervention is the identification of patients at risk for AKI or those with acute kidney damage before kidney function deteriorates. In this context, new biomarkers can help to detect cellular injury early. This way, a window for interventions can be opened. Several studies demonstrated the tissue-protective effect of remote ischemic preconditioning in various organs. There is clear evidence that use of balanced crystalloid fluids and the avoidance of hyperchloremic solutions for infusion therapy can reduce the incidence of AKI. Preliminary data show a protective effect if dexmedetomidine is used as a sedative agent following cardiac surgery. The most important intervention with proven efficacy to protect from AKI is aggressive hemodynamic stabilization. Summary Early identification of patients at risk for AKI is crucial to apply any protective intervention. An improved perioperative management is required to prevent AKI. Although pharmacological therapies aiming to protect AKI are under evaluation, hemodynamic optimization and avoidance of nephrotoxic drugs are critical for perioperative patient.

Purpose of review The increasing incidence of acute kidney injury has the immediate effect of a growing need for renal replacement therapy (RRT). Shedding light on the questions of who, when, why, and how RRT should be performed is difficult to accomplish because of ambiguous study results, poor quality evidence, and low standardization. Recent findings Critically ill patients are exposed to multiple factors known to deteriorate kidney function. Especially severe fluid overload is strongly associated with worse outcome and may be considered as a trigger for initiating RRT. In the absence of life-threatening complications, a strategy of early initiation of RRT might be most advantageous keeping in mind the potential adverse effects of RRT. By providing better hemodynamic stability and superior control of fluid balance continuous RRT is the first choice therapeutic tool as compared with intermittent techniques. The femoral and jugular veins are the preferred insertion sites for temporary catheters. Although data are still weak, there is some preliminary evidence that regional citrate anticoagulation is superior to systemic heparinization. Summary The best management of RRT is still a subject of controversy. Continuous RRT with regional citrate anticoagulation via a temporary catheter in a jugular vein is the recommended first choice treatment option in critically ill patients with acute kidney injury.

This review summarizes the approach to and recent developments in the treatment of acute right ventricular dysfunction and failure in the perioperative setting. Right ventricular failure, defined as the inability to deliver sufficient blood flow through the pulmonary circulation at normal central venous pressure, is a common problem in the perioperative setting and is associated with an increased mortality. The failure of the right ventricle is caused by reduced right ventricular contractility or an increased right ventricular afterload or both.Management of acute right ventricular failure continues to be challenging because of the poor understanding of the pathophysiology, difficulties in diagnosing, the absence of guidelines, and limited therapeutic options. Recent research efforts have led to an improved understanding of the underlying mechanisms and have established a reasonable therapeutic framework.Right ventricular dysfunction may cause venous congestion and systemic hypoperfusion. After identifying right ventricular dysfunction, the primary goal is to correct reversible causes of excessive load or reduced right-ventricular contractility. If the underlying abnormalities cannot be reversed, diuretic, vasodilator, or inotropic therapy may be required.

Chronic kidney disease (CKD) is an increasing health problem worldwide and is associated with a number of clinical challenges. In this paper, we review recent studies that deal with strategies for the management of patients with CKD undergoing surgery.Effective strategies for nephroprotection are crucial for the handling of patients with CKD in the perioperative setting to prevent complications and to avoid the progression of CKD. Due to the lack of perioperative studies with CKD patients there are only level 2 recommendations. First of all, this requires the identification of CKD patients through risk assessment and preoperative laboratory tests. In this regard, biomarkers, such as cystatin C may facilitate the detection of chronically impaired renal function. Secondly, particular attention should be paid to the maintenance of hemodynamic stability, including an adequate blood pressure and cardiac index and the preservation of intravascular volume. There is clear evidence that an unimpaired renal perfusion, guaranteed through hemodynamic stability, and an undisturbed fluid balance both reduce the incidence of acute kidney injury (AKI) and consequently the further deterioration of renal function. Thirdly, several studies demonstrate that tight glycemic control is associated with less renal impairment and better survival for patients with CKD. Lastly, the highest priority for the patient with CKD should be assigned to the prevention of AKI, which is an action of proven efficacy.Identification and risk stratification is crucial for the perioperative management of patients with CKD. To improve clinical outcomes, nonemergent procedures should be postponed, renal function optimized, nephrotoxic drugs avoided, and AKI prevented.

Purpose of review Although advancements in perioperative care have been made over the last decades, the perioperative outcome could not be improved adequately. Therefore, new therapeutic strategies are required to decrease morbidity and all-cause mortality in surgical patients. Remote ischemic preconditioning (RIPC), defined as brief and transient episodes of ischemia at a remote site before a subsequent injury of the target organ, is an adaptive response to protect for organ injury elicited by different stimuli. This review evaluates the current clinical evidence for RIPC as a potential tissue-protective strategy and discusses the underlying mechanism. Recent findings Several studies demonstrated the tissue-protective effect of RIPC in various organs, including the heart, brain, and kidney. However, the existence of controversial results may be explained by the fact that different study protocols were used and different patient populations were recruited. Summary RIPC may offer a novel inexpensive and noninvasive therapeutic strategy to alleviate organ injury in the perioperative period. However, adequately powered, large, multicenter clinical studies are necessary to accurately determine whether ischemic conditioning can improve the clinical outcomes of patients at risk for ischemia-reperfusion injury.