Active clinical trials for "Acute Kidney Injury"

Acute kidney injury (AKI) in critically ill trauma patients has been shown to significantly increase mortality, length of stay, and costs, however detection has proven difficult as markers like elevated creatinine and decreased urine output may take days to manifest and are late indicators of AKI. The combination of two urinary biomarkers, Tissue Inhibitor of Metalloproteinase 2 (TIMP-2) and Insulin-like Growth Factor Binding Protein 7 (IGFBP-7), has been shown to increase within 12 hours following renal insult, allowing assessment of risk for developing acute kidney injury. Therefore, the investigators plan to assess if acute kidney injury in critically ill trauma patients can be determined earlier using urinary TIMP-2 and IGFBP-7 via the NephroCheck testing system. These markers have not been specifically evaluated in trauma patients at risk of AKI.

Hepatorenal syndrome (HRS) is a common cause of acute kidney injury (AKI) in cirrhotic patients and has a one month survival rate of 50% and a 3 month survival rate of 20%. The leading theory behind HRS is selective vasoconstriction of renal vasculature in the setting of decreased systemic vascular resistance. Patients with liver cirrhosis suffer from a large degree of third spacing in the form of peripheral edema and ascites. In addition treatment with multiple drugs, including diuretics puts these patients at higher risks of prerenal AKI and ischemic acute tubular necrosis (ATN). AKI occurring due to HRS, prerenal AKI and ischemic or nephrotoxic ATN have different pathophysiologic mechanisms and are treated differently with significantly different outcomes. While renal perfusion is expected to be reduced in HRS and prerenal AKI, it is normal or increased in ATN. Prerenal AKI has the most favorable prognosis among these pathologies and treatment simply consists of volume expansion with blood, albumin, crystalloids or colloids. In clinical practice vasoactive agents such as midodrine and octreotide are used to increase the tone of splanchnic vessels and to improve renal perfusion. These interventions would not affect renal function in cases with ATN. Unfortunately, the diagnostic criteria proposed by the International Club for Ascites (ICA) for HRS are not specific and do not always exclude patients with other forms of acute kidney injury. Therefore, availability of a simple diagnostic tool for measurement of renal blood flow (RBF) at the bedside would be of great value in management of cases with cirrhosis of the liver presenting with acute reduction in kidney function. However, currently, there are no practical and simple tools available for this purpose. Contrast enhanced ultrasonography (CEU) involves the intravenous injection of gas-filled microbubbles to enhance the ultrasound image of the organs and mainly to assess tissue vascularity and blood flow. We and others have used CEU to assess changes in RBF in response to physiologic stimuli and therapeutic interventions. Here we propose a prospective, pilot diagnostic study to validate the use of CEU, in assessing RBF in cirrhotic patients with AKI, and to assess the utility of CEU to differentiate between causes of AKI in cirrhotic patients. Our hypothesis is that CEU will show arteriolar vasoconstriction and decreased blood flow in the renal cortex in patients with HRS which would not change in response to volume expansion. On the contrary, patients with prerenal AKI will have reduced RBF which will increase after volume expansion. Finally, those with ATN will not have a reduced RBF at baseline. We plan to enroll 25 patients with liver cirrhosis and acute kidney injury who are admitted to the University of Virginia hospital into the study. CEU will be performed on all subjects to measure baseline RBF. CEU will be repeated in all subjects within 24 hours after volume expansion with at least 1gm/kg of albumin (up to 100 gm/day) to assess a potential change. Hourly urine output and serum creatinine will be monitored for potential renal response to the volume expansion as part of clinical care. For the subgroup of subjects who receive treatment with combination therapy with albumin, midodrine, and octreotide (AMO) RBF assessment with CEU will be repeated after at least 48 hours of receiving this combination. Renal response will be assessed by monitoring urine output and serum creatinine monitored as part of clinical care. All subjects will have measurements of fractional excretion of sodium (FENa) and urea (FEUrea) and urine microscopy as a part of their routine clinical care (work up of AKI). The results of these tests and the response to volume expansion will be used to categorize subjects into three categories of AKI (HRS, prerenal AKI, ATN). Correlations between RBF and its changes between different therapeutic interventions and renal diagnosis will be tested in this study.

500 patients with normal renal function will be prospectively studied and incidence, spectrum and natural history of AKI (Acute Kidney Injury) will be observed in them and in 200 patients with abnormal renal function fulfilling AKI (Acute Kidney Injury) criteria will be prospectively studied for 1 year. Also biomarkers will be studied and validated as early predictors of AKI (Acute Kidney Injury).

Bedside ultrasonographic assessment of IVC size and IVC collapsibility index can be used to guide the management of patients with acute kidney injury with and without volume overload in the intensive care unit

The incidence of acute kidney injury after liver transplantation has been reported to be 17 to 95 percent, but no definite treatment has been reported yet. Therefore, it is important to identify and prevent reversible risk factors for acute kidney injury after liver transplantation. Previous studies have reported several preoperative clinical risk factors, but preoperative medication and intraoperative colloid administration and hemodynamic parameters have not been evaluated. Therefore, we attempt to evaluate perioperative risk factors and develop simplified clinical risk scoring model.

The aim of the study is to characterize the influence of continuous veno-venous hemodialysis on the cerebrovascular autoregulation.

The purpose of this study is to determine whether remote ischemic conditioning can improve the outcome after renal transplantation with deceased donor. Remote ischemic conditioning is performed on the patient receiving a kidney from a deceased donor. Remote ischemic conditioning is done during the operation by inflating a tourniquet on the patients leg before opening the blood circulation to the kidney. The study focus on both the immediate kidney function after the transplantation, but also on the extended kidney function one year after the transplantation.

Open elective abdominal aortic surgery is a high risk procedure involving clamping of the aorta. Indications include abdominal aortic aneurysm (AAA) or aortic occlusive disease (AOD) causing lower limb ischaemia. These patients are often regarded as one entity in postoperative study settings. However, previous studies indicate that risk profiles, inflammatory activity, and haemodynamic capacity may differ between these groups. The first aim of this study was to evaluate postoperative ICU-requirements after open elective abdominal aortic surgery, hypothesising that AAA-patients had longer ICU-stays and needed more mechanical ventilation or acute dialysis than did patients with AOD. The investigators see a relatively high incidence of postoperative acute kidney injury (AKI) following aortic surgery. Neutrophil Gelatinase Associated Lipocalcin (NGAL) may be useful in the early diagnosis of postopeative AKI. However, NGAL is also known as a marker of inflammatory activation. The ischaemia-reperfusion injury and subsequent inflammatory response to aortic cross clamping may per se induce a rise in NGAL despite intact renal function. Therefore NGAL may not be a reliable marker of AKI after AAS. The second aim of this study is to describe the changes in NGAL after AAS in patients with and without postoperative dialysis-dependent AKI.

Acute kidney injury after cardiac surgery has been reported to increase morbidity and mortality. Several risk scoring models for prediction of aortic kidney injury after cardiac surgery have been developed. However, predictive accuracy of these models is stil unclear. The aim of this study is to evaluate the accuracy of four pre-existing prediction models using a gray zone approach in patients who underwent aortic surgery in our institution.

This study is to collect blood and urine samples to help identify and validate protein biomarkers of recovery from moderate or severe acute kidney injury (AKI).