Introduction: Closed-loop spinal cord stimulation (CL-SCS) is a recently introduced system that records evoked compound action potentials (ECAPs) from the spinal cord elicited by each stimulation pulse and uses this information to automatically adjust the stimulation strength in real time, known as ECAP-controlled SCS. This innovative system compensates for fluctuations in the distance between the epidural leads and the spinal cord by maintaining the neural response (ECAP) at a predetermined target level. This data collection study was designed to assess the performance of the first CL-SCS system in a real-world setting under normal conditions of use in multiple European centers.
View Article and Find Full Text PDFIntensive Care Med Exp
December 2014
Background: The aim of the present study was to test the potential protective effects of the organic vanadium salt bis (maltolato) oxovanadium (BMOV; 15 mg/kg) in the context of renal ischemia/reperfusion (30 min of ischemia) and its effects on renal oxygenation and renal function in the acute phase of reperfusion (up to 90 min post-ischemia).
Methods: Ischemia was established in anesthetized and mechanically ventilated male Wistar rats by renal artery clamping. Renal microvascular and venous oxygenation were measured using phosphorimetry.
Background And Objectives: Acute kidney injury (AKI) is a clinical condition associated with a degree of morbidity and mortality despite supportive care, and ischemia/reperfusion injury (I/R) is one of the main causes of AKI. The pathophysiology of I/R injury is a complex cascade of events including the release of free oxygen radicals followed by damage to proteins, lipids, mitochondria, and deranged tissue oxygenation. In this study, we investigated whether the antioxidant ascorbic acid would be able to largely prevent oxidative stress and consequently, reduce I/R-related injury to the kidneys in terms of oxygenation, inflammation, and renal failure.
View Article and Find Full Text PDFBackground: In this study we investigated whether storage of red blood cells (RBCs) leads to alterations in nitrite reductase activity, hence in altered hypoxia-induced nitric oxide (NO) bioavailability and methemoglobin formation.
Study Design And Methods: Hypoxia-induced NO bioavailability and methemoglobin formation were measured in vitro after nitrite administration to fresh (<1 week of storage) and aged (5-6 weeks of storage) human RBC units and in blood samples of hemodiluted rats subjected to hypoxic ventilation after transfusion with fresh or aged human RBCs.
Results: In vitro, NO and methemoglobin levels 10 minutes after nitrite administration were lower in the fresh RBC samples compared to the aged RBC samples (p = 0.
Introduction: We aimed to test whether continuous recombinant human activated protein C (APC) administration would be able to protect renal oxygenation and function during endotoxemia in order to provide more insight into the role of coagulation and inflammation in the development of septic acute kidney injury.
Methods: In anesthetized, mechanically ventilated Wistar rats, endotoxemia was induced by lipopolysaccharide administration (10 mg/kg i.v.
Introduction: Fluid resuscitation therapy is the initial step of treatment for hemorrhagic shock. In the present study we aimed to investigate the acute effects of acetate-balanced colloid and crystalloid resuscitation on renal oxygenation in a rat model of hemorrhagic shock. We hypothesized that acetate-balanced solutions would be superior in correcting impaired renal perfusion and oxygenation after severe hemorrhage compared to unbalanced solutions.
View Article and Find Full Text PDFBackground: Perioperative red blood cell transfusions are commonly used in patients undergoing cardiac surgery to correct anemia caused by blood loss and hemodilution associated with cardiopulmonary bypass circulation. The aim of this investigation was to test the hypothesis that blood transfusion has beneficial effects on sublingual microcirculatory density, perfusion, and oxygenation. To this end, sidestream dark field (SDF) imaging and spectrophotometry were applied sublingually before and after blood transfusion during cardiac surgery.
View Article and Find Full Text PDFAlthough it is generally accepted that oxygen-quenched phosphorescence decay traces can be analyzed using the exponential series method (ESM), its application until now has been limited to a few (patho)physiological studies, probably because the reliability of the recovered oxygen tension (pO(2)) histograms has never been extensively evaluated and lacks documentation. The aim of this study was, therefore, to evaluate the use of the ESM to adequately determine pO(2) histograms from phosphorescence decay traces. For this purpose we simulated decay traces corresponding to uni- and bimodal pO(2) distributions and recovered the pO(2) histograms at different signal-to-noise ratios (SNRs).
View Article and Find Full Text PDFEven though renal hypoxia is believed to play a pivotal role in the development of acute kidney injury, no study has specifically addressed the alterations in renal oxygenation in the early onset of renal ischemia-reperfusion (I/R). Renal oxygenation depends on a balance between oxygen supply and consumption, with the nitric oxide (NO) as a major regulator of microvascular oxygen supply and oxygen consumption. The aim of this study was to investigate whether I/R induces inducible NO synthase (iNOS)-dependent early changes in renal oxygenation and the potential benefit of iNOS inhibitors on such alterations.
View Article and Find Full Text PDFBest Pract Res Clin Anaesthesiol
June 2007
Despite the common use of red-blood-cell transfusions in clinical practice, actual beneficial effects of red blood cells have never been demonstrated. On the contrary, several studies suggest that red-blood-cell transfusions are associated with higher risks of morbidity and mortality. The effects of the duration of storage on the efficacy of red blood cells have therefore been questioned in a number of studies.
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