Use of dopamine in acute renal failure: a meta-analysis

The Genetic Determinants of Renal Impairment Following Cardiac Surgery

Cardiac surgery is frequently performed, and acute renal dysfunction is a common adverse event following this procedure. Cardiac surgery-related renal injury independently predicts longer hospital stays and greater rates of morbidity and mortality. Although much work has been completed toward better understanding of this phenomenon, the state of knowledge concerning surgery-related renal injury remains limited. Currently, there is no effective paradigm to identify patients who are at risk for this condition; the specific mechanisms of renal injury during surgery are incompletely understood; and few therapies exist to prevent or treat this phenomenon. To better understand this common clinical problem, recent research has focused on the importance of genetic variability within the physiological and patho-physiological systems that underlie renal dysfunction following cardiac surgery. Emphasizing the importance of using genetics to elucidate molecular mechanisms of this disease, this article reviews the current literature on genetic polymorphisms and post cardiac surgery-related renal dysfunction.

Atrial Natriuretic Peptide Stimulates Dopamine Tubular Transport by Organic Cation Transporters: A Novel Mechanism to Enhance Renal Sodium Excretion

The aim of this study was to demonstrate the effects of atrial natriuretic peptide (ANP) on organic cation transporters (OCTs) expression and activity, and its consequences on dopamine urinary levels, Na+, K+-ATPase activity and renal function. Male Sprague Dawley rats were infused with isotonic saline solution during 120 minutes and randomized in nine different groups: control, pargyline plus tolcapone (P+T), ANP, dopamine (DA), D-22, DA+D-22, ANP+D-22, ANP+DA and ANP+DA+D-22. Renal functional parameters were determined and urinary dopamine concentration was quantified by HPLC. Expression of OCTs and D1-receptor in membrane preparations from renal cortex tissues were determined by western blot and Na+, K+-ATPase activity was determined using in vitro enzyme assay. 3H-DA renal uptake was determined in vitro. Compared to P+T group, ANP and dopamine infusion increased diuresis, urinary sodium and dopamine excretion significantly. These effects were more pronounced in ANP+DA group and reversed by OCTs blockade by D-22, demonstrating that OCTs are implied in ANP stimulated-DA uptake and transport in renal tissues. The activity of Na+, K+-ATPase exhibited a similar fashion when it was measured in the same experimental groups. Although OCTs and D1-receptor protein expression were not modified by ANP, OCTs-dependent-dopamine tubular uptake was increased by ANP through activation of NPR-A receptor and protein kinase G as signaling pathway. This effect was reflected by an increase in urinary dopamine excretion, natriuresis, diuresis and decreased Na+, K+-ATPase activity. OCTs represent a novel target that links the activity of ANP and dopamine together in a common mechanism to enhance their natriuretic and diuretic effects.

A Clinical Approach to the Acute Cardiorenal Syndrome

Acute kidney injury is a frequent complication of acute heart failure syndromes, portending an adverse prognosis. Acute cardiorenal syndrome represents a unique form of acute kidney injury specific to acute heart failure syndromes. The pathophysiology of acute cardiorenal syndrome involves renal venous congestion, ineffective forward flow, and impaired renal autoregulation caused by neurohormonal activation. Biomarkers reflecting different aspects of acute cardiorenal syndrome pathophysiology may allow patient phenotyping to inform prognosis and treatment. Adjunctive vasoactive, neurohormonal, and diuretic therapies may relieve congestive symptoms and/or improve renal function, but no single therapy has been proved to reduce mortality in acute cardiorenal syndrome.

Renal-Dose Dopamine: From Hypothesis to Paradigm to Dogma to Myth and, Finally, Superstition?

Acute renal failure (ARF) is common in the critically ill and is associated with a high mortality rate. Its pathogenesis is not understood. Because animal models use ischemia to induce experimental ARF, there is the widespread belief that lack of blood flow is responsible for ARF. Low-dose dopamine (LDD) has been shown to increase renal blood flow in animal and in human volunteers. Thus, it has been administered to humans for almost 3 decades in the belief that it would lead to renal arterial vasodilation and increase renal blood flow (RBF). However, the etiology of ARF in critical illness is likely multifactorial, and the contribution of hypovolemia and reduced renal perfusion is unknown. Furthermore, interindividual variation in the pharmacokinetics of dopamine typically results in poor correlation between blood levels and administered dose, making accurate and reliable delivery of LDD difficult. Finally, dopamine is a proximal tubular diuretic that increases Na+ delivery to tubular cells, thus increasing their oxygen demands. Accordingly, even if LDD were able to preferentially increase RBF, there is no guarantee that it would restore renal parenchymal oxygen homeostasis. More important, 2 meta-analyses and a large double-blind, prospective, multiple-center, randomized controlled trial have failed to demonstrate that dopamine protects the kidney in critically ill patients with ARF. Currently, there is insufficient evidence to support the use of renal-dose dopamine in the intensive care unit.

Variables during Care of Adult Donors That Can Influence Outcomes of Kidney Transplantation

Publications that relate characteristics of donors to renal function of recipients are reviewed. Most publications report retrospective observations that relate outcomes to donor variables that cannot be altered during donor care. Factors that can be altered in adult donors in an effort to improve recipients' outcomes include urine output and creatinine level. Increasing urine output to more than 100 mL/h, at least during the hour before explantation, and returning the creatinine level to match its serum concentration when the patient was admitted can improve outcomes. Ways of accomplishing those goals during donor care are discussed, with emphasis on support of renal blood flow.

Postoperative management

Most patients undergoing major aortic surgery have multiple comorbidities and are at high risk of postoperative complications that affect multiple organ systems. Different aortic pathologies and surgical repair techniques have specific impact on the postoperative course. Ischemia-reperfusion injury is the common denominator in aortic surgery and influences the integrity of end-organ function. Common postoperative problems include hemodynamic instability due to the immediate inflammatory response, renal impairment, spinal cord ischemia, respiratory failure with prolonged mechanical ventilation, and gastrointestinal symptoms such as ileus or mesenteric ischemia. Focused care bundles to establish homeostasis and a team working toward an early functional recovery determine the success of effective rehabilitation and outcomes after aortic surgery.

Acute kidney injury in severe sepsis: pathophysiology, diagnosis, and treatment recommendations

OBJECTIVE

To review the unique pathophysiology of sepsis-induced acute kidney injury (AKI) and highlight the relevant aspects of the Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline for Acute Kidney Injury that may apply to veterinary patients.

DATA SOURCES

Electronic search of MEDLINE database.

HUMAN DATA SYNTHESIS

Sepsis-induced AKI is diagnosed in up to 47% of human ICU patients and is seen as a major public health concern associated with increased mortality and increased progression to chronic kidney disease (CKD). Consensus criteria for the definition and classification of AKI has allowed for accurate description of the epidemiology of patients with AKI. AKI develops from a complex relationship between the initial insult and activation of inflammation and coagulation. In contrast to the traditional view, clinical and experimental data dispute the role of renal ischemia-reperfusion in the development of sepsis-induced AKI. Renal tubular dysfunction with activation of the tubuloglomerular feedback mechanism appears to be a crucial contributor to sepsis-induced AKI. Furosemide and n-acetylcysteine (NAC) do not appear to be helpful in the treatment of AKI. Hydroxyethyl starches (HES), dopamine, and supraphysiological concentrations of chloride are harmful in patients with AKI.

VETERINARY DATA SYNTHESIS

Community and hospital-acquired AKI is a significant factor affecting survival in critical ill patients. Sepsis-induced AKI occurs in 12% of dogs with abdominal sepsis and is an important contributor to mortality. Early detection of AKI in hospitalized patients currently offers the best opportunity to improve patient outcome. The use of urinary biomarkers to diagnose early AKI should be evaluated in critical care patients.

CONCLUSION

Veterinary clinical trials comparing treatment choices with the development of AKI are needed to make evidence-based recommendations for the prevention and treatment of AKI.

Anaesthetic Considerations in the Perioperative Management of Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy has emerged as one of the primary modalities of treatment of diffuse peritoneal malignancies. It is a complex surgical procedure with the patients facing major and potentially life threatening alterations of haemodynamic, respiratory, metabolic and thermal balance with significant fluid losses and the perioperative management is challenging for anaesthesiologists and intensive care physicians. Though the alterations are short lived, these patients require advanced organ function monitoring and support perioperatively. The anaesthesiologist is involved in the management of haemodynamics, respiratory function, coagulation, haematologic parameters, fluid balance, thermal variations, and metabolic and nutritional support perioperatively. The chemotherapy instillate used are known to cause nephrotoxicity, cardiotoxicity, dyselectrolytemia and lactic acidosis. The preoperative polypharmacy for pain control, previous surgery and/or chemotherapy, malnourished status secondary to feeding problems and tumour wasting syndrome make the task all the more challenging. The anaesthesiologist also needs to consider the perioperative care from a quality of life perspective and proper preoperative counselling is important. The present overview summarizes the challenges faced by the anaesthesiologist regarding the pathophysiological alterations during the Cytoreductive surgery and Hyperthermic intraperitoneal chemotherapy in the preoperative, intraoperative and postoperative periods.

Acute Kidney Injury in Cardiac Surgery and Cardiac Intensive Care

Acute kidney injury (AKI) is a serious postoperative complication following cardiac surgery. Despite the incidence of AKI requiring temporary renal replacement therapy being low, it is nonetheless associated with high morbidity and mortality. Therefore, preventing AKI associated with cardiac surgery can dramatically improve outcomes in these patients. The pathogenesis of AKI is multifactorial and many attempts to prevent or treat renal injury have been met with limited success. In this article, we will discuss the incidence and risk factors for cardiac surgery associated AKI, including the pathophysiology, potential biomarkers of injury, and treatment modalities.

Focus on renal congestion in heart failure

Hospitalizations due to heart failure are increasing steadily despite advances in medicine. Patients hospitalized for worsening heart failure have high mortality in hospital and within the months following discharge. Kidney dysfunction is associated with adverse outcomes in heart failure patients. Recent evidence suggests that both deterioration in kidney function and renal congestion are important prognostic factors in heart failure. Kidney congestion in heart failure results from low cardiac output (forward failure), tubuloglomerular feedback, increased intra-abdominal pressure or increased venous pressure. Regardless of the cause, renal congestion is associated with increased morbidity and mortality in heart failure. The impact on outcomes of renal decongestion strategies that do not compromise renal function should be explored in heart failure. These studies require novel diagnostic markers that identify early renal damage and renal congestion and allow monitoring of treatment responses in order to avoid severe worsening of renal function. In addition, there is an unmet need regarding evidence-based therapeutic management of renal congestion and worsening renal function. In the present review, we summarize the mechanisms, diagnosis, outcomes, prognostic markers and treatment options of renal congestion in heart failure.

Cardiorenal syndrome: review of our current understanding

Renal and cardiac diseases are both prevalent and carry significant morbidity and mortality. They share common vascular risk factors and are physiologically interlinked. Dysfunction in one organ affects the other. Concurrent renal and cardiac disease is associated with a poor prognosis. This close relationship is reflected through cardiorenal syndrome. A classification system has been proposed; however, the underlying process is complex and multifactorial. Management of this syndrome focuses on improving heart function, reducing volume overload, and managing heart failure and chronic kidney disease. This, however, is challenging, limited by paucity of evidence and may lead to suboptimal therapy. Increased recognition of this syndrome should raise awareness in providing early therapy and avoiding adverse outcomes due to under-treatment. In this article, we provide an overview of our current understanding of cardiorenal syndrome, as well as its pathophysiology and treatment options.

Extensive variability in vasoactive agent therapy: a nationwide survey in Chinese intensive care units

BACKGROUND

Inconsistencies in the use of the vasoactive agent therapy to treat shock are found in previous studies. A descriptive study was proposed to investigate current use of vasoactive agents for patients with shock in Chinese intensive care settings.

METHODS

A nationwide survey of physicians was conducted from August 17 to December 30, 2012. Physicians were asked to complete a questionnaire which focused on the selection of vasoactive agents, management in the use of vasopressor/inotropic therapy, monitoring protocols when using these agents, and demographic characteristics.

RESULTS

The response rate was 65.1% with physicians returning 586 valid questionnaires. Norepinephrine was the first choice of a vasopressor used to treat septic shock by 70.8% of respondents; 73.4% of respondents favored dopamine for hypovolemic shock; and 68.3% of respondents preferred dopamine for cardiogenic shock. Dobutamine was selected by 84.1%, 64.5%, and 60.6% of respondents for septic, hypovolemic, and cardiogenic shock, respectively. Vasodilator agents were prescribed by physicians in the management of cardiogenic shock (67.1%) rather than for septic (32.3%) and hypovolemic shock (6.5%). A significant number of physicians working in teaching hospitals were using vasoactive agents in an appropriate manner when compared to physicians in nonteaching hospitals.

CONCLUSIONS

Vasoactive agent use for treatment of shock is inconsistent according to self-report by Chinese intensive care physicians; however, the variation in use depends upon the form of shock being treated and the type of hospital; thus, corresponding educational programs about vasoactive agent use for shock management should be considered.

Volume Overload in Heart Failure: An Evidence-Based Review of Strategies for Treatment and Prevention

Acute decompensated heart failure is the leading cause of hospital admission in the United States, with a high risk of readmission within 30 days. Most acute decompensated heart failure admissions are driven by congestive signs and symptoms resulting from fluid and sodium overload. We reviewed the evidence base addressing the management and prevention of fluid overload in heart failure, focusing on recent clinical trials. All the references in this review were obtained through PubMed and had at least 1 of the following key words: heart failure and volume overload, congestion, loop diuretics, thiazide diuretics, aldosterone antagonists, dopamine, cardiorenal syndrome, nesiritide, vasopressin antagonists, ultrafiltration, sodium restriction, fluid restriction, telemonitoring, and invasive hemodynamic monitoring. We also reviewed relevant references cited in the obtained articles, especially articles addressing methods of treating or preventing volume overload in patients with heart failure.

Neonatal Acute Kidney Injury

In recent years, there have been significant advancements in our understanding of acute kidney injury (AKI) and its impact on outcomes across medicine. Research based on single-center cohorts suggests that neonatal AKI is very common and associated with poor outcomes. In this state-of-the-art review on neonatal AKI, we highlight the unique aspects of neonatal renal physiology, definition, risk factors, epidemiology, outcomes, evaluation, and management of AKI in neonates. The changes in renal function with gestational and chronologic age are described. We put forth and describe the neonatal modified Kidney Diseases: Improving Global Outcomes AKI criteria and provide the rationale for its use as the standardized definition of neonatal AKI. We discuss risk factors for neonatal AKI and suggest which patient populations may warrant closer surveillance, including neonates <1500 g, infants who experience perinatal asphyxia, near term/ term infants with low Apgar scores, those treated with extracorporeal membrane oxygenation, and those requiring cardiac surgery. We provide recommendations for the evaluation and treatment of these patients, including medications and renal replacement therapies. We discuss the need for long-term follow-up of neonates with AKI to identify those children who will go on to develop chronic kidney disease. This review highlights the deficits in our understanding of neonatal AKI that require further investigation. In an effort to begin to address these needs, the Neonatal Kidney Collaborative was formed in 2014 with the goal of better understanding neonatal AKI, beginning to answer critical questions, and improving outcomes in these vulnerable populations.

Impact of Compliance with a Care Bundle on Acute Kidney Injury Outcomes: A Prospective Observational Study

Background

A recent report has highlighted suboptimal standards of care for acute kidney injury (AKI) patients in England. The objective of this study was to ascertain if improvement in basic standard of care by implementing a care bundle (CB) with interruptive alert improved outcomes in patients with AKI.

Methods

An AKI CB linked to electronic recognition of AKI, coupled with an interruptive alert, was introduced to improve basic care delivered to patients with AKI. Outcomes were compared in patients who had the CB completed within 24 hours (early CB group) versus those who didn’t have the CB completed or had it completed after 24 hours.

Results

In the 11-month period, 2297 patients had 2500 AKI episodes, with 1209 and 1291 episodes occurring before and after implementation of the AKI CB with interruptive alert, respectively. The CB was completed within 24 hours in 306 (12.2%) of AKI episodes. In-hospital case-fatality was significantly lower in the early CB group (18% versus 23.1%, p 0.046). Progression to higher AKI stages was lower in the early CB group (3.9% vs. 8.1%, p 0.01). In multivariate analysis, patients in the early CB group had lower odds of death at discharge (0.641; 95% CI 0.46, 0.891), 30 days (0.707; 95% CI 0.527, 0.950), 60 days (0.704; 95% CI 0.526, 0.941) and after a median of 134 days (0.771; 95% CI 0.62, 0.958).

Conclusions

Compliance with AKI CB was associated with a decrease in case-fatality and reduced progression to higher AKI stage. Further interventions are required to improve utilization of the CB.

Renal endothelial dysfunction in acute kidney ischemia reperfusion injury

Acute kidney injury is associated with alterations in vascular tone that contribute to an overall reduction in GFR. Studies in animal models indicate that ischemia triggers alterations in endothelial function that contribute significantly to the overall degree and severity of a kidney injury. Putative mediators of vasoconstriction that may contribute to the initial loss of renal blood flow and GFR are highlighted. In addition, there is discussion of how intrinsic damage to the endothelium impairs homeostatic responses in vascular tone as well as promotes leukocyte adhesion and exacerbating the reduction in renal blood flow. The timing of potential therapies in animal models as they relate to the evolution of AKI, as well as the limitations of such approaches in the clinical setting are discussed. Finally, we discuss how acute kidney injury induces permanent alterations in renal vascular structure. We posit that the cause of the sustained impairment in kidney capillary density results from impaired endothelial growth responses and suggest that this limitation is a primary contributing feature underlying progression of chronic kidney disease.

Renal replacement therapy in children

Acute kidney injury (AKI) affects 3.9/1000 at-risk children in the United States, a number that has been increasing as critically ill and injured children have access to improved care and the diagnosis of AKI is being made more accurately. Children with AKI have a higher mortality and hospital length of stay as compared to children without AKI. Renal replacement therapy can improve outcomes in these patients. This article reviews the pathophysiology of AKI and the modalities, indications, and outcomes of renal replacement for children with AKI.

N-acyl dopamine derivates as lead compound for implementation in transplantation medicine

Conjugates of fatty acids with ethanolamine, amino acids or monoamine neurotransmitters occur widely in nature giving rise to so-called endocannabinoids. Anandamide and 2-arachidonoyl glycerol are the best characterized endocannabinoids activating both cannabinoid receptors (CB1 and CB2) and transient receptor potential vanilloid type 1 (TRPV1) channels (anandamide) or activating cannabinoid receptors only (2-arachidonoyl glycerol). TRPV1 is also activated by vanilloids, such as capsaicin, and endogenous neurolipins, e.g. N-arachidonoyl dopamine (NADA) and N-oleoyl dopamine (OLDA). Because donor dopamine treatment has shown to improve transplantation outcome in renal and heart recipients, this review will mainly focus on the biological activities of N-acyl dopamine derivates (NADD) as potential non-hemodynamic alternative for implementation in transplantation medicine. Hence the influence of NADD on transplantation relevant entities, i.e. cold inflicted injury, cytoprotection, I/R-injury, immune-modulation and inflammation will be summarized. The cytoprotective properties of endogenous endocannabinoids in this context will be briefly touched upon.

Essentials of sepsis management

Despite remarkable advances in the knowledge of infection and human response to it, sepsis continues to be one of the most common challenges surgeons and critical care providers face. Surgeons confront the problem of infection every day, in treating established infections or reacting to a consequence of surgical intervention. Infections after surgery continue to be a problem despite massive efforts to prevent them. Patients rely on the surgeon's ability to recognize infection and treat it. Also, preventing nosocomial infection and antibiotic resistance is a primary responsibility. This article describes diagnostic and therapeutic measures for sepsis in the perioperative surgical patient.

Serum creatinine role in predicting outcome after cardiac surgery beyond acute kidney injury

Serum creatinine is still the most important determinant in the assessment of perioperative renal function and in the prediction of adverse outcome in cardiac surgery. Many biomarkers have been studied to date; still, there is no surrogate for serum creatinine measurement in clinical practice because it is feasible and inexpensive. High levels of serum creatinine and its equivalents have been the most important preoperative risk factor for postoperative renal injury. Moreover, creatinine is the mainstay in predicting risk models and risk factor reduction has enhanced its importance in outcome prediction. The future perspective is the development of new definitions and novel tools for the early diagnosis of acute kidney injury largely based on serum creatinine and a panel of novel biomarkers.

Postoperative management of dogs with gastric dilatation and volvulus

The objective of the study was to review the veterinary literature for evidence-based and common clinical practice supporting the postoperative management of dogs with gastric dilatation and volvulus (GDV). GDV involves rapid accumulation of gas in the stomach, gastric volvulus, increased intragastric pressure, and decreased venous return. GDV is characterized by relative hypovolemic-distributive and cardiogenic shock, during which the whole body may be subjected to inadequate tissue perfusion and ischemia. Intensive postoperative management of the patients with GDV is essential for survival. Therapy in the postoperative period is focused on maintaining tissue perfusion along with intensive monitoring for prevention and early identification of ischemia-reperfusion injury (IRI) and consequent potential complications such as hypotension, cardiac arrhythmias, acute kidney injury (AKI), gastric ulceration, electrolyte imbalances, and pain. In addition, early identification of patients in need for re-exploration owing to gastric necrosis, abdominal sepsis, or splenic thrombosis is crucial. Therapy with intravenous lidocaine may play a central role in combating IRI and cardiac arrhythmias. The most serious complications of GDV are associated with IRI and consequent systemic inflammatory response syndrome and multiple organ dysfunction syndrome. Other reported complications include hypotension, AKI, disseminated intravascular coagulation, gastric ulceration, and cardiac arrhythmias. Despite appropriate medical and surgical treatment, the reported mortality rate in dogs with GDV is high (10%-28%). Dogs with GDV that are affected with gastric necrosis or develop AKI have higher mortality rates.

Implementing the Kidney Disease: Improving Global Outcomes/acute kidney injury guidelines in ICU patients

PURPOSE OF REVIEW

Acute kidney injury (AKI) is a frequent finding in critically ill patients and is associated with adverse outcomes. With the purpose of improving outcome of AKI, the Kidney Disease: Improving Global Outcomes (KDIGO) group, a group of experts in critical care nephrology, has presented a set of guidelines in 2012, based on the evidence gathered until mid 2011. This review will update these guidelines with recent evidence.

RECENT FINDINGS

Early application of a set of therapeutic measures - a bundle - is advised for the prevention and therapy of AKI. Hemodynamic optimization remains the cornerstone of prevention and treatment of AKI. Fluid resuscitation should be with isotonic crystalloids. Recent evidence demonstrated a higher risk for renal replacement therapy (RRT) and mortality in hydroxyethyl starch-exposed patients. Further, blood pressure should be maintained by the use of vasopressors in vasomotor shock. Nephrotoxic drugs should be avoided or stopped when possible. Contrast-associated AKI should be prevented by prehydration with either NaCl 0.9% or a bicarbonate solution. Other therapies, including intravenous N-acetylcysteine and hemofiltration are not recommended. Optimal timing of RRT remains controversial. Fluid overload remains an important determinant for the initiation of RRT. Continuous therapies are preferred in hemodynamically unstable patients; otherwise, choice of modality does not impact on outcomes.

SUMMARY

The KDIGO guidelines as presented in 2012 provide guidelines on the domain of definition of AKI, prevention and treatment, contrast-induced AKI and dialysis interventions for AKI. Especially, early application of a set of measures, the AKI bundle, may prevent AKI and improve outcome.

Management of sepsis in neutropenic patients: 2014 updated guidelines from the Infectious Diseases Working Party of the German Society of Hematology and Medical Oncology (AGIHO)

Sepsis is a major cause of mortality during the neutropenic phase after intensive cytotoxic therapies for malignancies. Improved management of sepsis during neutropenia may reduce the mortality of cancer therapies. Clinical guidelines on sepsis treatment have been published by others. However, optimal management may differ between neutropenic and non-neutropenic patients. Our aim is to give evidence-based recommendations for haematologist, oncologists and intensive care physicians on how to manage adult patients with neutropenia and sepsis.

[Perioperative acute kidney injury and failure]

Perioperative period is very likely to lead to acute renal failure because of anesthesia (general or perimedullary) and/or surgery which can cause acute kidney injury. Characterization of acute renal failure is based on serum creatinine level which is imprecise during and following surgery. Studies are based on various definitions of acute renal failure with different thresholds which skewed their comparisons. The RIFLE classification (risk, injury, failure, loss, end stage kidney disease) allows clinicians to distinguish in a similar manner between different stages of acute kidney injury rather than using a unique definition of acute renal failure. Acute renal failure during the perioperative period can mainly be explained by iatrogenic, hemodynamic or surgical causes and can result in an increased morbi-mortality. Prevention of this complication requires hemodynamic optimization (venous return, cardiac output, vascular resistance), discontinuation of nephrotoxic drugs but also knowledge of the different steps of the surgery to avoid further degradation of renal perfusion. Diuretics do not prevent acute renal failure and may even push it forward especially during the perioperative period when venous retourn is already reduced. Edema or weight gain following surgery are not correlated with the vascular compartment volume, much less with renal perfusion. Treatment of perioperative acute renal failure is similar to other acute renal failure. Renal replacement therapy must be mastered to prevent any additional risk of hemodynamic instability or hydro-electrolytic imbalance.

Moving beyond supportive care--current status of specific therapies in pediatric acute kidney injury

Acute kidney injury (AKI) remains a significant challenge, leading to increased morbidity, mortality, and medical costs. Therapy for AKI to this point has largely been supportive; specific interventions to treat established AKI have had minimal effect. Review of the pathogenesis of AKI reveals complex, interacting mechanisms, including changes in microcirculation, the immune system, and inflammation, and cell death from both necrosis and apoptosis. Past definitions of AKI have been imprecise; newer methods for AKI identification and classification, including novel biomarkers and improved criteria for defining AKI, may permit earlier intervention with greater potential for success. With improved understanding of pathophysiology and the opportunity for intervention before AKI is fully established, clinicians may be able to move beyond supportive care and improve outcomes.

Atorvastatin treatment attenuates renal injury in an experimental model of ischemia-reperfusion in rats

BACKGROUND

Recent studies in animal models have shown that statins can protect against renal failure independent of their lipid-lowering actions, and there is also an association between statin use and improved renal function after suprarenal aortic clamping. We investigated the hypothesis that post-ischemic acute renal failure could be ameliorated with atorvastatin (ATO) treatment and the possible molecular mechanisms in a model of ischemia-reperfusion (IR) in rats.

METHODS

Twenty-four male Sprague-Dawley rats were divided into three groups: sham, IR, and IR + ATO. ATO was given by a single intraperitoneal injection (10 mg/kg) 30 min before reperfusion in the IR + ATO group. The IR group and sham group received saline vehicle via the intraperitoneal route.

RESULTS

After 24 h of IR, serum creatinine levels were increased in the IR group compared with the sham group (p < 0.001). ATO treatment reduced the elevation of serum creatinine level by 18% (p < 0.05) and significantly increased the creatinine clearance rate (p < 0.001). Concentrations of advanced oxidation protein products and malondialdehyde were reduced in the ATO group, approaching levels observed in sham-group rats. ATO treatment alleviated pathological changes in renal tubular cells. Protein and mRNA levels of intercellular adhesion molecule-1 and monocyte chemotactic protein-1 were reduced significantly.

CONCLUSIONS

These data suggest that direct protection of injured kidneys by ATO was possible even though the drug was injected 30 min before reperfusion, and that ATO may reduce IR injury by anti-inflammatory effects and by reducing oxidation stress.

Treatment options for severe sepsis and septic shock

Despite significant advances in the understanding of the pathophysiology of sepsis, severe sepsis and septic shock continue to be associated with high morbidity and mortality. Eradication of infection, with appropriate antibiotics and source control, remains the cornerstone of sepsis management, but does not ensure survival. Aggressive supportive care, such as fluid resuscitation, vasoactive agents or mechanical ventilation, is often required. With the exception of drotrecogin alfa, attempts to modulate the inflammatory response in sepsis have generally been unsuccessful. Early goal-directed therapy targeting adequate central venous oxygen saturation appears to improve outcome. Recently, there has been renewed interest in the use of corticosteroids, not as anti-inflammatory agents, but as replacement therapy. There is also some evidence to suggest that tight glucose control may improve outcome in these patients.

Acute decompensated heart failure: update on new and emerging evidence and directions for future research

Acute decompensated heart failure (ADHF) is a complex clinical event associated with excess morbidity and mortality. Managing ADHF patients is challenging because of the lack of effective treatments that both reduce symptoms and improve clinical outcomes. Existing guideline recommendations are largely based on expert opinion, but several recently published trials have yielded important data to inform both current clinical practice and future research directions. New insight has been gained regarding volume management, including dosing strategies for intravenous loop diuretics and the role of ultrafiltration in patients with heart failure and renal dysfunction. Although the largest ADHF trial to date (ASCEND-HF, using nesiritide) was neutral, promising results with other investigational agents have been reported. If these findings are confirmed in phase III trials, novel compounds, such as relaxin, omecamtiv mecarbil, and ularitide, among others, may become therapeutic options. Translation of research findings into quality clinical care can not be overemphasized. Although many gaps in knowledge exist, ongoing studies will address issues around delivery of evidence-based care to achieve the goal of improving the health status and clinical outcomes of patients with ADHF.

Surviving sepsis campaign: international guidelines for management of severe sepsis and septic shock: 2012

OBJECTIVE

To provide an update to the "Surviving Sepsis Campaign Guidelines for Management of Severe Sepsis and Septic Shock," last published in 2008.

DESIGN

A consensus committee of 68 international experts representing 30 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict of interest policy was developed at the onset of the process and enforced throughout. The entire guidelines process was conducted independent of any industry funding. A stand-alone meeting was held for all subgroup heads, co- and vice-chairs, and selected individuals. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development.

METHODS

The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide assessment of quality of evidence from high (A) to very low (D) and to determine the strength of recommendations as strong (1) or weak (2). The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized. Some recommendations were ungraded (UG). Recommendations were classified into three groups: 1) those directly targeting severe sepsis; 2) those targeting general care of the critically ill patient and considered high priority in severe sepsis; and 3) pediatric considerations.

RESULTS

Key recommendations and suggestions, listed by category, include: early quantitative resuscitation of the septic patient during the first 6 hrs after recognition (1C); blood cultures before antibiotic therapy (1C); imaging studies performed promptly to confirm a potential source of infection (UG); administration of broad-spectrum antimicrobials therapy within 1 hr of recognition of septic shock (1B) and severe sepsis without septic shock (1C) as the goal of therapy; reassessment of antimicrobial therapy daily for de-escalation, when appropriate (1B); infection source control with attention to the balance of risks and benefits of the chosen method within 12 hrs of diagnosis (1C); initial fluid resuscitation with crystalloid (1B) and consideration of the addition of albumin in patients who continue to require substantial amounts of crystalloid to maintain adequate mean arterial pressure (2C) and the avoidance of hetastarch formulations (1C); initial fluid challenge in patients with sepsis-induced tissue hypoperfusion and suspicion of hypovolemia to achieve a minimum of 30 mL/kg of crystalloids (more rapid administration and greater amounts of fluid may be needed in some patients) (1C); fluid challenge technique continued as long as hemodynamic improvement, as based on either dynamic or static variables (UG); norepinephrine as the first-choice vasopressor to maintain mean arterial pressure ≥ 65 mm Hg (1B); epinephrine when an additional agent is needed to maintain adequate blood pressure (2B); vasopressin (0.03 U/min) can be added to norepinephrine to either raise mean arterial pressure to target or to decrease norepinephrine dose but should not be used as the initial vasopressor (UG); dopamine is not recommended except in highly selected circumstances (2C); dobutamine infusion administered or added to vasopressor in the presence of a) myocardial dysfunction as suggested by elevated cardiac filling pressures and low cardiac output, or b) ongoing signs of hypoperfusion despite achieving adequate intravascular volume and adequate mean arterial pressure (1C); avoiding use of intravenous hydrocortisone in adult septic shock patients if adequate fluid resuscitation and vasopressor therapy are able to restore hemodynamic stability (2C); hemoglobin target of 7-9 g/dL in the absence of tissue hypoperfusion, ischemic coronary artery disease, or acute hemorrhage (1B); low tidal volume (1A) and limitation of inspiratory plateau pressure (1B) for acute respiratory distress syndrome (ARDS); application of at least a minimal amount of positive end-expiratory pressure (PEEP) in ARDS (1B); higher rather than lower level of PEEP for patients with sepsis-induced moderate or severe ARDS (2C); recruitment maneuvers in sepsis patients with severe refractory hypoxemia due to ARDS (2C); prone positioning in sepsis-induced ARDS patients with a PaO2/FIO2 ratio of ≤ 100 mm Hg in facilities that have experience with such practices (2C); head-of-bed elevation in mechanically ventilated patients unless contraindicated (1B); a conservative fluid strategy for patients with established ARDS who do not have evidence of tissue hypoperfusion (1C); protocols for weaning and sedation (1A); minimizing use of either intermittent bolus sedation or continuous infusion sedation targeting specific titration endpoints (1B); avoidance of neuromuscular blockers if possible in the septic patient without ARDS (1C); a short course of neuromuscular blocker (no longer than 48 hrs) for patients with early ARDS and a Pao2/Fio2 < 150 mm Hg (2C); a protocolized approach to blood glucose management commencing insulin dosing when two consecutive blood glucose levels are > 180 mg/dL, targeting an upper blood glucose ≤ 180 mg/dL (1A); equivalency of continuous veno-venous hemofiltration or intermittent hemodialysis (2B); prophylaxis for deep vein thrombosis (1B); use of stress ulcer prophylaxis to prevent upper gastrointestinal bleeding in patients with bleeding risk factors (1B); oral or enteral (if necessary) feedings, as tolerated, rather than either complete fasting or provision of only intravenous glucose within the first 48 hrs after a diagnosis of severe sepsis/septic shock (2C); and addressing goals of care, including treatment plans and end-of-life planning (as appropriate) (1B), as early as feasible, but within 72 hrs of intensive care unit admission (2C). Recommendations specific to pediatric severe sepsis include: therapy with face mask oxygen, high flow nasal cannula oxygen, or nasopharyngeal continuous PEEP in the presence of respiratory distress and hypoxemia (2C), use of physical examination therapeutic endpoints such as capillary refill (2C); for septic shock associated with hypovolemia, the use of crystalloids or albumin to deliver a bolus of 20 mL/kg of crystalloids (or albumin equivalent) over 5 to 10 mins (2C); more common use of inotropes and vasodilators for low cardiac output septic shock associated with elevated systemic vascular resistance (2C); and use of hydrocortisone only in children with suspected or proven "absolute"' adrenal insufficiency (2C).

CONCLUSIONS

Strong agreement existed among a large cohort of international experts regarding many level 1 recommendations for the best care of patients with severe sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for this important group of critically ill patients.

Can we prevent or treat renal dysfunction in acute heart failure?

Most patients with heart failure (HF) already have or develop renal dysfunction; this might contribute to their poor outcome. Current treatment for HF can also contribute to worsen renal function. High furosemide doses are traditionally associated with worsening renal function (WRF), but patients with fluid overload may benefit of aggressive fluid removal. Unfortunately, promising therapies like vasopressin antagonists and adenosine antagonists have not been demonstrated to improve outcomes. Likewise, correction of low renal blood flow through dopamine, inotropic agents, or vasodilators does not seem to be associated with a clear benefit. However, transient WRF associated with acute HF treatment may not necessarily portend a poor prognosis. In this review, we focus on the strategies to detect renal dysfunction in acute HF, the underlying pathophysiological mechanisms, and the potential treatments.

Renal dysfunction in acute heart failure: epidemiology, mechanisms and assessment

Renal dysfunction is often present and/or worsens in patients with heart failure and this is associated with increased costs of care, complications and mortality. The cardiorenal syndrome can be defined as the presence or development of renal dysfunction in patients with heart failure. Its mechanisms are likely related to low cardiac output, increased venous congestion and renal venous pressure, neurohormonal and inflammatory activation and local changes, such as adenosine release. Many drugs, including loop diuretics, may contribute to worsening renal function through the activation of some of these mechanisms. Renal damage is conventionally defined by the increase in creatinine and blood urea nitrogen blood levels. However, these changes may be not related with renal injury or prognosis. New biomarkers of renal injury seem promising but still need to be validated. Thus, despite the epidemiological evidence, we are still lacking of satisfactory tools to assess renal injury and function and its prognostic significance.

Diagnosis, evaluation, and management of acute kidney injury: a KDIGO summary (Part 1)

Acute kidney injury (AKI) is a common and serious problem affecting millions and causing death and disability for many. In 2012, Kidney Disease: Improving Global Outcomes completed the first ever, international, multidisciplinary, clinical practice guideline for AKI. The guideline is based on evidence review and appraisal, and covers AKI definition, risk assessment, evaluation, prevention, and treatment. In this review we summarize key aspects of the guideline including definition and staging of AKI, as well as evaluation and nondialytic management. Contrast-induced AKI and management of renal replacement therapy will be addressed in a separate review. Treatment recommendations are based on systematic reviews of relevant trials. Appraisal of the quality of the evidence and the strength of recommendations followed the Grading of Recommendations Assessment, Development and Evaluation approach. Limitations of the evidence are discussed and a detailed rationale for each recommendation is provided.

Surviving Sepsis Campaign: international guidelines for management of severe sepsis and septic shock, 2012

OBJECTIVE

To provide an update to the "Surviving Sepsis Campaign Guidelines for Management of Severe Sepsis and Septic Shock," last published in 2008.

DESIGN

A consensus committee of 68 international experts representing 30 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict of interest policy was developed at the onset of the process and enforced throughout. The entire guidelines process was conducted independent of any industry funding. A stand-alone meeting was held for all subgroup heads, co- and vice-chairs, and selected individuals. Teleconferences and electronic-based discussion among subgroups and among the entire committee served as an integral part of the development.

METHODS

The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide assessment of quality of evidence from high (A) to very low (D) and to determine the strength of recommendations as strong (1) or weak (2). The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized. Recommendations were classified into three groups: (1) those directly targeting severe sepsis; (2) those targeting general care of the critically ill patient and considered high priority in severe sepsis; and (3) pediatric considerations.

RESULTS

Key recommendations and suggestions, listed by category, include: early quantitative resuscitation of the septic patient during the first 6 h after recognition (1C); blood cultures before antibiotic therapy (1C); imaging studies performed promptly to confirm a potential source of infection (UG); administration of broad-spectrum antimicrobials therapy within 1 h of the recognition of septic shock (1B) and severe sepsis without septic shock (1C) as the goal of therapy; reassessment of antimicrobial therapy daily for de-escalation, when appropriate (1B); infection source control with attention to the balance of risks and benefits of the chosen method within 12 h of diagnosis (1C); initial fluid resuscitation with crystalloid (1B) and consideration of the addition of albumin in patients who continue to require substantial amounts of crystalloid to maintain adequate mean arterial pressure (2C) and the avoidance of hetastarch formulations (1B); initial fluid challenge in patients with sepsis-induced tissue hypoperfusion and suspicion of hypovolemia to achieve a minimum of 30 mL/kg of crystalloids (more rapid administration and greater amounts of fluid may be needed in some patients (1C); fluid challenge technique continued as long as hemodynamic improvement is based on either dynamic or static variables (UG); norepinephrine as the first-choice vasopressor to maintain mean arterial pressure ≥65 mmHg (1B); epinephrine when an additional agent is needed to maintain adequate blood pressure (2B); vasopressin (0.03 U/min) can be added to norepinephrine to either raise mean arterial pressure to target or to decrease norepinephrine dose but should not be used as the initial vasopressor (UG); dopamine is not recommended except in highly selected circumstances (2C); dobutamine infusion administered or added to vasopressor in the presence of (a) myocardial dysfunction as suggested by elevated cardiac filling pressures and low cardiac output, or (b) ongoing signs of hypoperfusion despite achieving adequate intravascular volume and adequate mean arterial pressure (1C); avoiding use of intravenous hydrocortisone in adult septic shock patients if adequate fluid resuscitation and vasopressor therapy are able to restore hemodynamic stability (2C); hemoglobin target of 7-9 g/dL in the absence of tissue hypoperfusion, ischemic coronary artery disease, or acute hemorrhage (1B); low tidal volume (1A) and limitation of inspiratory plateau pressure (1B) for acute respiratory distress syndrome (ARDS); application of at least a minimal amount of positive end-expiratory pressure (PEEP) in ARDS (1B); higher rather than lower level of PEEP for patients with sepsis-induced moderate or severe ARDS (2C); recruitment maneuvers in sepsis patients with severe refractory hypoxemia due to ARDS (2C); prone positioning in sepsis-induced ARDS patients with a PaO (2)/FiO (2) ratio of ≤100 mm Hg in facilities that have experience with such practices (2C); head-of-bed elevation in mechanically ventilated patients unless contraindicated (1B); a conservative fluid strategy for patients with established ARDS who do not have evidence of tissue hypoperfusion (1C); protocols for weaning and sedation (1A); minimizing use of either intermittent bolus sedation or continuous infusion sedation targeting specific titration endpoints (1B); avoidance of neuromuscular blockers if possible in the septic patient without ARDS (1C); a short course of neuromuscular blocker (no longer than 48 h) for patients with early ARDS and a PaO (2)/FI O (2) <150 mm Hg (2C); a protocolized approach to blood glucose management commencing insulin dosing when two consecutive blood glucose levels are >180 mg/dL, targeting an upper blood glucose ≤180 mg/dL (1A); equivalency of continuous veno-venous hemofiltration or intermittent hemodialysis (2B); prophylaxis for deep vein thrombosis (1B); use of stress ulcer prophylaxis to prevent upper gastrointestinal bleeding in patients with bleeding risk factors (1B); oral or enteral (if necessary) feedings, as tolerated, rather than either complete fasting or provision of only intravenous glucose within the first 48 h after a diagnosis of severe sepsis/septic shock (2C); and addressing goals of care, including treatment plans and end-of-life planning (as appropriate) (1B), as early as feasible, but within 72 h of intensive care unit admission (2C). Recommendations specific to pediatric severe sepsis include: therapy with face mask oxygen, high flow nasal cannula oxygen, or nasopharyngeal continuous PEEP in the presence of respiratory distress and hypoxemia (2C), use of physical examination therapeutic endpoints such as capillary refill (2C); for septic shock associated with hypovolemia, the use of crystalloids or albumin to deliver a bolus of 20 mL/kg of crystalloids (or albumin equivalent) over 5-10 min (2C); more common use of inotropes and vasodilators for low cardiac output septic shock associated with elevated systemic vascular resistance (2C); and use of hydrocortisone only in children with suspected or proven "absolute"' adrenal insufficiency (2C).

CONCLUSIONS

Strong agreement existed among a large cohort of international experts regarding many level 1 recommendations for the best care of patients with severe sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for this important group of critically ill patients.

2013 WSES guidelines for management of intra-abdominal infections

Despite advances in diagnosis, surgery, and antimicrobial therapy, mortality rates associated with complicated intra-abdominal infections remain exceedingly high.The 2013 update of the World Society of Emergency Surgery (WSES) guidelines for the management of intra-abdominal infections contains evidence-based recommendations for management of patients with intra-abdominal infections.

Sepsis: update in the management

Sepsis and septic shock are syndromes that overlap between several disciplines and subspecialties. Emerging evidence suggests that sepsis may be associated with short- and long-term adverse outcomes, even when the syndrome does not appear to be severe and is not managed in the intensive care unit. Hence, all practicing clinicians need to be familiar with the fundamental principles of diagnosis and management of sepsis. In this review, we have summarized the key components in the management of sepsis/septic shock, including early recognition, early resuscitation, principles of antibiotic therapy, organ support, and role of adjunctive therapies.