Active clinical trials for "Reperfusion Injury"

Ischemia/reperfusion injury following aortic cross-clamping for vascular surgery leads to systemic hemodynamic and microcirculatory perturbances. The use of different anesthetic regimens may have an impact on tissue perfusion. The aim of this study was to explore changes in microvascular perfusion in patients undergoing elective open abdominal aortic aneurysm repair under balanced or total intravenous anesthesia. Prospective observational study on 40 patients scheduled for elective open infrarenal abdominal aortic aneurysm repair, who received balanced (desflurane + remifentanil, n=20) or total intravenous anesthesia (TIVA, propofol + remifentanil using target-controlled infusion, n=20) according to the clinician's decision. A goal-directed hemodynamic management was applied in all patients. Hemodynamics and arterial/venous blood gases were compared before anesthesia induction (baseline) and at end-surgery. Changes in sublingual microvascular flow and density were assessed with incident dark field illumination imaging. Near infrared spectroscopy was applied on the thenar eminence with a vascular occlusion test (VOT) to assess variations in the peripheral muscle tissue oxygenation and microcirculatory reactivity.

Ventricular fibrillation (VF)-related sudden cardiac death (SCD) is a leading cause of mortality. Patients may survive with neurological damage despite state-of-the-art treatment. Current biological and imaging parameters show significant limitations on early predicting cerebral performance at hospital admission. A spectral-based model was recently suggested to correlate time-dependent VF spectral changes with acute cerebral injury in comatose survivors after cardiac arrest, which opens the possibility to implement early prognostic tools in clinical practice. The AWAKE trial is an investigator-initiated, multicenter, observational trial aiming to validate a spectral-based model to early predict cerebral performance and survival in resuscitated comatose survivors admitted to specialized intensive care units. The primary clinical outcome is favorable neurological performance (FNP) during hospitalization. Patients will be categorized into 4 subsets of NP according to the risk score obtained from the predictive model. The secondary clinical outcomes are survival to hospital discharge, and FNP and survival after 6 months of follow-up. Model-derived categorization will be compared with clinical outcomes to assess model sensitivity, specificity and accuracy. Eligible patients will be included prospectively and retrospectively, using an electronic Case Report Form to enter data from medical records and in-person interviews. Patients will be divided into: study group (predictive data required) including comatose (Glasgow Coma Scale -GCS- ≤8) survivors undergoing temperature control after return of spontaneous circulation (RoSC), and control group including patients who regain consciousness (GCS=15) after RoSC. VF tracings prior to the first DC shock will be digitized and analyzed to derive spectral data and risk scores.

Background: The cardiomyocytes apoptosis induced by ischemia-reperfusion(I/R) is one of the most important factors in the myocardial I/R injury(MIRI) undergoing cardiac valve replacement with cardiopulmonary bypass(CVRCPB),and Ischemic postconditioning (I-postC) can inhibit apoptosis of myocardial cells. Consequently, this study investigated the key genes and apoptosis signaling pathways of myocardium in patients undergoing CVRCPB. Methods: A total of 36 New York Heart Association class II or III patients with rheumatic heart disease (RHD) of both sexes, aged 21-59 years, who were scheduled for first cardiac valve replacement with CPB in the investigators' hospital from February 2014 to May 2015, were randomly divided into the following three groups (n=12 each): negative control group (NEG group); I/R group (POS group); and I-postC group (Treat group). In the Treat group, the procedure involved 5 min before opening the ascending aorta, aortic unclamping for 30 s, and cross-clamping for 30 s for three cycles, after which the ascending aorta was completely opened. The NEG and Treat groups were not treated. Thirty-six patients were assessed for arrhythmia and recovery of myocardial contractile function after reperfusion by electrocardiograms and degree of dependence on vasoactive drugs. The myocardial tissues of the right atrial appendage were obtained at 3 min before CPB was established in the NEG group, and at 45 min after opening the aorta in the POS and Treat groups. In all three groups, the myocardial tissues of the right atrial appendage were obtained and preserved at -80°C for further experiments. The right atrial appendage of three patients randomly selected in each group was fixed with RNA later (Qiagen, Hilden, Germany) in a centrifuge tube overnight at 4°C, and then preserved at -20°C for RNA extraction. Human 12×135K Gene Array profiling of mRNA expressions was undertaken in human cardiac muscle cells. Differentially expressed mRNAs verified by quantitative real-time RT-PCR were subjected to pathway analysis. The mRNA expressions of AIF, APAF1, CYCS, Bax, caspase-3, caspase-9, caspase-6, caspase-7, BCL2, BAG1, and PI3K were assessed by real-time RT-PCR and western blot analysis. The levels of myocardial apoptosis induced by I/R were investigated by TUNEL assays. The changes in MIRI induced by myocardial apoptosis were investigated by pathologic examination of the myocardium.

In this proof-of-concept study, forearm vulnerability to ischemic exercise is studied in patients with type 1 diabetes mellitus with and without prior ischemic preconditioning (short period of ischemia that protects against subsequent ischemic exercise). Annexin A5 scintigraphy is used to quantify subtle signs of mild and reversible forearm injury that results from ischemic exercise. The following hypotheses are tested: Patients with type 1 diabetes are not more vulnerable to ischemic injury as compared with previously studied healthy volunteers. Ischemic preconidtioning is still present in patients with type 1 diabetes. Depending on the validity of hypothesis 2, the effect of short pharmacological interventions are studied on vulnerability to forearm ischemia/reperfusion injury in the absence or presence of local forearm ischemic preconditioning.

The number of patients with end stage renal disease is increasing continuously and kidney transplantation is the preferred treatment modality. Modern immunosuppressive therapy has reduced the number of acute rejection episodes and increased one year allograft survival dramatically. Nonetheless, 4% of allografts are lost beyond the first year annually due to a multifactorial process and the latter number has not changed for decades. One of the most important factors to determine long-term success after kidney transplantation is the quality of the donor organ. For example, transplantation of organs from elderly or extended criteria donors results in reduced allograft and patient survival. In previous work, the investigators specifically focused on age-associated molecular signatures including telomere length and mRNA expression levels of the cell cycle inhibitors CDKN2A (p16INK4a) and CDKN1A (p21WAF1) and assessed these parameters in pre-implantation biopsies of 54 patients. In a linear regression analysis CDKN2A turned out to be the best single predictor for serum creatinine after 1 year followed by donor age and telomere length. A multiple linear regression analysis revealed that the combination of CDKN2A values and donor age yielded even higher predictive values. In another study the investigators were able to show an interaction between donor age and use of calcineurin inhibitors with regard to outcome after renal transplantation. During these past activities an extensive set of whole genome transcriptomics profile information from zero hour biopsies and clinical follow-up data has been collected. In the TOPVAS study, existing data derived from 72 of the above mentioned set of biopsies (exclusion of live donor grafts) will be analysed with state of the art bioinformatical/system biology tools to derive a general (not purely age associated) prognostic biomarker panel for functional transplant outcome two years after transplantation. This marker panel will also be used to define organs preferentially suitable for MMF/tacrolimus based immunosuppression. Both panels will then be validated for their prognostic and predictive information on the long-term outcome after transplantation in a new independent patient population treated with tacrolimus and MMF. In addition to biomarker assessment and in pursue of identifying alternative and/or complementary parameters with predictive value , an advanced morphological investigation of tissue biopsy life stains will be performed employing an innovative cell viability staining technology ("BIOPSYCHRONOLOGY").

Single-centre observational study over one year investigating the mechanisms of muscle homeostasis in patients with acute skeletal muscle atrophy following major aortic surgery

Myocardial protection has become an essential adjunctive measure in cardiac surgery to bail the myocardium out of ischemia/reperfusion-induced damage during the operation. Experimental studies have shown that lipid emulsion infusion just before reperfusion (i.e., intralipid postconditioning (ILPC)) could reduce myocardial infarct sizes, improve cardiac function, and reduce myocardial I/R injuries, despite the interesting experimental findings, the potential clinical usage of lipid emulsion in preventing myocardial I/R injury needs to be further investigated.

"Remote Ischaemic PreConditioning" (RIPC) is performed prior to partial nephrectomy. Postoperative calprotectin dynamics and Blood Oxygen-Level-Dependent (BOLD) MRI are used to to demonstrate the potential renoprotective effect of RIPC

Major liver surgery often requires the surgeon to temporarily halt the afferent blood flow in order to prevent excessive blood loss. However, this predisposes the liver to a detrimental inflammatory response once the circulation is restored. Altogether, the effects that result from this temporary withdrawal of blood are known as ischemia and reperfusion (I/R) injury, and the extent to which this occurs determines the functional outcome of the liver after surgery. Recently, it has become clear that (over)activation of the immune system forms the mainstay of I/R injury in the liver. More importantly, it has been shown in animal models that self-antigens, which are normal cellular constituents that become immunogenic mediators following their release from dying cells, are involved in the earliest stages of I/R injury of the liver. Clinical data on the release self-antigens in I/R injury are however scarce to date. Therefore, the aim of this study is to investigate the release of self-antigens in patients that undergo a major liver resection with or without withdrawal of the liver's blood flow. Also, the results will be correlated to genes involved in the inflammatory response as well as clinical parameters for liver damage and function.

The primary purpose of this study is to correlate new cardiac imaging modalities (2D, 3D echocardiography, contrast echocardiography, strain analysis and cardiac MRI) to biochemical parameters as the L-arginine-nitric oxide pathway and inflammatory cascades to characterize the reperfusion injury following myocardial infarction and thus providing a basis for further diagnostic and therapeutic approaches.