Search Results (9)

Extracorporeal circulation (ECC) is frequently implemented in a vast array of modalities such as hemodialysis, cardiopulmonary bypass, extracorporeal membrane oxygenation (ECMO), and others. Patients receiving any such therapy are frequently encumbered with chronic inflammation, which is inherently accompanied by oxidative stress. However, ECC treatments themselves are also responsible for sustaining or promoting inflammation. On these grounds, an in vitro study was designed to investigate the therapeutic potential of molecular hydrogen (H₂) against pro-inflammatory agents in ECC settings. Five miniature ECMO circuits and a small vial (Control) were primed with heparinized blood from healthy adult donors (n = 7). Three of the ECMO systems were injected with lipopolysaccharide (LPS), out of which one was additionally treated with an H₂ gas mixture. After 6 h, samples were drawn for the assessment of specific biomarkers (MCP-1, MPO, MDA-a, TRX1, and IL-6). Preliminary results indicate a progressive oxidative and inflammatory response between the six systems. Circulation has triggered inflammation and blood trauma, but the staggering influence of LPS in this outcome is indisputable. Accordingly, hydrogen’s remedial potential becomes immediately apparent as biomarker concentrations tend to be lower in the H₂-handled circuit. Future research should have distinct objectives (e.g., dosage/duration/cycle of hydrogen administration) in order to ascertain the optimal protocol for patient treatment. Full article

Cardiac surgery (CS) with extracorporeal circulation (ECC), induces intense oxidative stress (OS) and systemic inflammatory response (SIR), which may seriously affect postoperative lung function. We aimed to test if high parenteral (200 mg/kg/24 h) daily doses of Vitamin C (VitC), given within 48 h after the beginning of the operation, may reduce the incidence and severity of postoperative pulmonary complications (PPCs) in CS patients. This single-center, prospective, randomized, single-blinded, interventional trial included 150 patients, assigned to control Group A (n = 75) and interventional Group B (n = 75). Group B intraoperatively received one-fourth (i.e., 50 mg/kg) of the planned daily Vit C dose, divided into three equal parts and diluted in 10 mL of normal saline, while Group A received an equal volume of normal saline at the same time frames (i.e., the induction of anesthesia, aortic cross-clamp release, and sternal closure). After 6 h from the first intraoperative dose, the following regimen was applied: Group B: 50 mg/kg, 30 min i.v. infusion of VitC in 50 mL of normal saline, every 6 h, for the next 48 h, and Group A: 30 min i.v. infusion of an equal volume of normal saline every 6 h, for the next 48 h. Modified Kroenke’s score was used to determine the incidence and severity of PPCs. The overall incidence of PPCs was 36.7% and was significantly lower in Group B (13.3% vs. 60.0%, p < 0.001). The PPCs severity score was also significantly lower in Group B (1 vs. 3, p < 0.001). In addition, patients from Group B had significantly less damaged lungs, better postoperative renal function, shorter ICU stays, fewer ICU re-admissions, and lower hospital mortality. No VitC-related adverse effects were recorded. High parenteral daily VitC doses given within 48 h after the beginning of CS are safe and effective in reducing the incidence and severity of PPCs. A multicenter RCT is needed to confirm these results. Full article

Patients undergoing coronary revascularization with extracorporeal circulation or cardiopulmonary bypass (CPB) may develop several biochemical changes in the microcirculation that lead to a systemic inflammatory response. Surgical incision, post-CPB reperfusion injury and blood contact with non-endothelial membranes can activate inflammatory signaling pathways that lead to the production and activation of inflammatory cells, with cytokine production and oxidative stress. This inflammatory storm can cause damage to vital organs, especially the heart, and thus lead to complications in the postoperative period. In addition to the organic pathophysiology during and after the period of exposure to extracorporeal circulation, this review addresses new perspectives for intraoperative treatment and management that may lead to a reduction in this inflammatory storm and thereby improve the prognosis and possibly reduce the mortality of these patients. Full article

Therapeutic plasma exchange (TPE) is an efficient extracorporeal blood purification technique to remove circulating autoantibodies and other pathogenic substances. Its mechanism of action in immune-mediated neurological disorders includes immediate intravascular reduction of autoantibody concentration, pulsed induction of antibody redistribution, and subsequent immunomodulatory changes. Conventional TPE with 1 to 1.5 total plasma volume (TPV) exchange is a well-established treatment in Guillain-Barre Syndrome, Chronic Inflammatory Demyelinating Polyradiculoneuropathy, Neuromyelitis Optica Spectrum Disorder, Myasthenia Gravis and Multiple Sclerosis. There is insufficient evidence for the efficacy of so-called low volume plasma exchange (LVPE) (<1 TPV exchange) implemented either by the conventional or by a novel nanomembrane-based TPE in these neurological conditions, including their impact on conductivity and neuroregenerative recovery. In this narrative review, we focus on the role of nanomembrane-based technology as an alternative LVPE treatment option in these neurological conditions. Nanomembrane-based technology is a promising type of TPE, which seems to share the basic advantages of the conventional one, but probably with fewer adverse effects. It could play a valuable role in patient management by ameliorating neurological symptoms, improving disability, and reducing oxidative stress in a cost-effective way. Further research is needed to identify which patients benefit most from this novel TPE technology. Full article

The contact of blood with the bioincompatible membranes of the dialyzer, which is part of the extracorporeal circuit during hemodialysis (HD), causes upregulation of various cellular and non-cellular processes, including massive generation and release of reactive oxygen species (ROS), (which is one of the primary causes of anemia in chronic renal failure). We hypothesize that near-infrared (NIR) radiation possesses antioxidant properties and is considered to protect the red blood cell (RBC) membrane by enhancing its resilience to negative pressures. Our experimental setup consisted of an HD machine equipped with a dialyzer with a polyamide membrane; whole bovine blood was examined in vitro in blood-treated circulation. Blood samples were taken at 0, 5, 15, and 30 min during the HD therapy. We also assessed osmotic fragility, hematocrit, hemolysis, and oxidative stress as a concentration of reactive thiobarbituric acid substances (TBARS). Our results have shown that RBC membrane peroxidation increased significantly after 30 min of circulation, whereas the TBARS level in NIR-treated blood remained relatively steady throughout the experiment. The osmotic fragility of NIR-irradiated samples during dialysis was decreased compared to control samples. Our studies confirm that in vitro, blood photobiomodulation using NIR light diminishes oxidative damage during HD and can be considered a simultaneous pretreatment strategy for HD. Full article

Heart disease requires a surgical approach sometimes. Cardiac-surgery patients develop heart failure associated with ischemia induced during extracorporeal circulation. This complication could be decreased with anesthetic drugs. The cardioprotective effects of halogenated agents are based on pre- and postconditioning (sevoflurane, desflurane, or isoflurane) compared to intravenous hypnotics (propofol). We tried to put light on the shadows walking through the line of the halogenated anesthetic drugs’ effects in several enzymatic routes and oxidative stress, waiting for the final results of the ACDHUVV-16 clinical trial regarding the genetic modulation of this kind of drugs. Full article

Reactive oxygen species (ROS) play a physiological role in the modulation of several functions of the vascular wall; however, increased ROS have detrimental effects. Hence, oxidative stress has pathophysiological impacts on the control of the vascular tone and cardiac functions. Recent experimental studies reported the involvement of increased ROS in the mechanism of hypertension, as this disorder associates with increased production of pro-oxidants and decreased bioavailability of antioxidants. In addition, increased ROS exposure is found in ischemia-reperfusion, occurring in acute myocardial infarction and cardiac surgery with extracorporeal circulation, among other settings. Although these effects cause major heart damage, at present, there is no available treatment. Therefore, it should be expected that antioxidants counteract the oxidative processes, thereby being suitable against cardiovascular disease. Nevertheless, although numerous experimental studies agree with this notion, interventional trials have provided mixed results. A better knowledge of ROS modulation and their specific interaction with the molecular targets should contribute to the development of novel multitarget antioxidant effective therapeutic strategies. The complex multifactorial nature of hypertension, acute myocardial infarction, and postoperative atrial fibrillation needs a multitarget antioxidant strategy, which may give rise to additive or synergic protective effects to achieve optimal cardioprotection. Full article

Hemodialysis (HD) is the most common method of renal replacement therapy. Besides toxins, it eliminates nutrients from the circulation, such as ascorbic acid (AA). HD-patients present AA deficiency more often than representatives of the general population, also due to dietary restrictions. This condition aggravates oxidative stress and inflammation related to uremia and extracorporeal circulation and increases cardiovascular risk followed by mortality. Supplementation of AA seems to be a promising approach in the treatment of hemodialysis patients. Many successful interventions restored plasma AA concentration in HD patients by enteral or intravenous supplementation, concomitantly inhibiting oxidative stress and inflammation. A significant number of studies reported opposite, serious pro-oxidant effects of AA. In this narrative review, we present studies, commenting on their limitations; on AA plasma or serum concentration and the influence of its supplementation on protein and lipid peroxidation, DNA damage, reactive oxygen species generation, paraoxonase activity, advanced glycation endproducts, and C-reactive protein (CRP) concentration. Moreover, in terms of safety, the possible development of oxalosis in HD patients regarding the intravenous or enteral route of AA administration is discussed. Unequivocal clinical results of recent studies on hemodialysis patients are displayed. Full article

Extracorporeal circulation (ECC) methods are being increasingly used for mechanical support of respiratory and cardio-circulatory failure. Especially, cardiopulmonary bypass (CPB) during cardiovascular surgery, sustenance of the patient’s life by providing an appropriate blood flow and oxygen supply to principal organs. On the other hand, systemic inflammatory responses in patients undergoing cardiovascular surgery supported by CPB contribute significantly to CPB-associated mortality and morbidity. Our previous research showed that CPB causes a systemic inflammatory response and organ damage in a small animal CPB model. We have been studying the effects of hyperoxia and blood plasma substitute on CPB. In this review, we present a study focusing on the systemic inflammatory response during CPB, along with our findings. Full article