Biomedical subjects

A Krouzecký

Publications and source records attributed to A Krouzecký.

8 recordsLinked to original sources

PubMed2003

[Acute kidney failure in critically ill patients and its prevention].

Acute renal failure often complicates the course of critically illness and can contribute to high morbidity and mortality. In most cases acute renal failure represents a part of the multiple organ dysfunction syndrome and it is usually related to the ischemic and/or toxic injury of tubular cells (acute tubular necrosis, ATN). The presented paper reviews the mechanisms involved in this two types of tubular cells injury. It analyzes the measures of kidney protection during critical illness, which include optimization of systemic and intrarenal hemodynamics as well as avoidance of nephrotoxic drugs. It describes the most common nephrotoxic drugs and proposes principles of their safer use. Potential strategies to stimulate kidney function recovery are also discussed.

Acute Kidney Injury↗

PubMed2003

Enteral nutrition and hepatosplanchnic region in critically ill patients - friends or foes?

Enteral nutrition (EN) is a preferred way of feeding in critically ill patients unless obvious contraindications such as ileus or active gastrointestinal bleeding are present. Early enteral nutrition as compared to delayed EN or total parenteral nutrition decreases morbidity in postsurgical and trauma patients. The hepatosplanchnic region plays a pivotal role in the pathophysiology of sepsis and multiple organ dysfunction syndrome. The beneficial effects of EN on splanchnic perfusion and energy metabolism have been documented both in healthy volunteers and animal models of sepsis, hemorrhagic shock and burns. By contrast, EN may increase splanchnic metabolic demands, which in turn may lead to oxygen and/or energy demand/supply mismatch, especially when hyperemic response to EN is not preserved. Therefore, the timing of initiation and the dose of EN in patients with circulatory failure requiring vasoactive drugs are a matter of controversy. Interestingly, the results of recent clinical studies suggest that early enteral nutrition may not be harmful even in patients with circulatory compromise. Nevertheless, possible onset of serious complications, the non-occlusive bowel necrosis in particular, have to be kept in mind. Unfortunately, there is only a limited number of clinically applicable monitoring tools for the effects of enteral nutrition in critically ill patients.

Animals↗

PubMed2003

[Rhabdomyolysis--development, causes, sequelae and therapy].

Rhabdomyolysis is a syndrome characterized by striated muscle necrosis and the release of intracellular muscle constituents into the circulation. The severity of illness ranges from asymptomatic elevations of muscle enzymes in the serum to life-threatening cases associated with extreme enzyme elevations, electrolyte imbalances, and acute renal failure. This chapter reviews recent knowledge of pathophysiologic mechanisms leading to myocytes injury, diseases its causes, consequences and treatment options. Particular attention is focused on rhabdomyolysis in critically ill patients.

Humans↗

PubMed2002

[Fluid resuscitation in conditions with disorders of capillary permeability].

Fluid resuscitation remains a cornerstone in the treatment of various types of circulatory failure. Alterations in microvascular permeability are a hallmark of a number of inflammatory conditions including sepsis, septic shock, burns and the acute respiratory distress syndrome. As a result, the loss of plasma fluid into the interstitial space leads to hypovolaemia and tissue hypoperfusion. Administration of large volumes of fluids in often necessary to restore the nutritional blood flow to tissues. This strategy, however, involves the risk of interstitial edema formation, which in turn may further impair tissue oxygen distribution. The presented paper briefly reviews the principles of transvascular fluid exchange and the pathophysiology of capillary permeability. It discusses the ongoing controversy on the optimal way and the end points of volume replacement as well as the choice of fluid in conditions associated with capillary leakage.

Capillary Leak Syndrome↗

PubMed2002

[Gastrointestinal tract dysfunction in critical illness].

Until relatively recently, the gastrointestinal (GI) tract was considered a dormant, metabolically and immunologically inactive organ in critically illnesses. However, the GI tract provides a number of crucial functions that, in fact, may influence morbidity and mortality of many critically ill patients. Its large absorptive area provides a site for nutrient digestion and utilization and serves as an important barrier preventing the systemic absorption of intraluminal microbes and its toxic products. Moreover, the GI tract is the largest reservoir of lymphocytes in the body, which significantly contribute to the immune response of the critically ill patients. The gut dysfunction occurs frequently and early in the intensive care patients. Abnormal colonization, impaired intestinal epithelial barrier function and bacterial translocation represent the key components of gut failure implicating in the pathogenesis of sepsis and multiorgan dysfunction. This review summarizes recent insights into the role of the gut in critically ill patients with particular focus on 1) the basis of "gut-origin hypothesis", 2) pathophysiology of gut dysfunction, 3) monitoring of intestinal function, and 4) protective measures and novel therapeutic strategies.

Bacterial Translocation↗

PubMed2002

The effect of heparin rinse on the biocompatibility of continuous veno-venous hemodiafiltration.

UNLABELLED: The aims of our cross-over randomized study were (1) to assess hemostasis in patients with acute renal failure (ARF) and (2) to determine whether or not the generally recommended heparin rinse of the extracorporeal circuit (ECC) prior to the procedure affects thrombogenicity, complement activation, and leukocyte count in blood during continuous venovenous hemodiafiltration (CVVHDF). Eleven critically ill ARF patients were treated, in random order, using CVVHDF in postdilution setup following ECC rinse with saline (A) with heparin at a concentration of 2,000 IU/L (10 procedures), (B) with heparin at a concentration of 10,000 IU/L (7 procedures), and (C) without heparin (9 procedures). Except for the rinse, anticoagulation therapy did not differ in individual patients during the procedures. Blood was withdrawn before, and at minutes 15, 60, and 360 invariably at diafilter inlet and outlet. Compared with healthy individuals, patients showed lower blood thrombocyte counts (153 vs 233*10(9)/L, p<0.01, arithmetic means, Student's t test), longer aPTT (44 vs 36 s, p<0.05), higher plasma levels of heparin (0.1 vs 0.0 U/mL, p<0.05), D-dimer (1129 vs 36 ng/mL, p<0.001) and beta-thromboglobulin (BTG) (159 vs 37 U/mL, p<0.001) prior to CVVHDF. The comparison of procedures with different rinsing technique did not reveal any significant difference in their effects on blood thrombocyte and leukocyte counts, aPTT, plasma levels of heparin, BTG, thrombin-antithrombin III complexes, D-dimer, or the C5a complement component. CONCLUSIONS: (1) Patients indicated for CVVHDF show impaired hemostasis involving thrombocytes, coagulation, and fibrinolysis, (2) no beneficial effect of heparin rinse on CVVHDF ECC thrombogenicity, complement activation or blood leukocyte counts was demonstrated.

Acute Kidney Injury↗

PubMed2001

[Extravascular lung water in acute respiratory distress syndrome: pathophysiology, monitoring and therapeutic possibilities].

Excessive amount of extravascular lung water (EVLW) resulting from increased permeability of alveolo-capillary membrane is a pathophysiological hallmark of acute respiratory distress syndrome (ARDS). Increased EVLW produces hypoxemia by interference with gas exchange. During shock resuscitation, in disorders in which microvascular endothelial integrity is impaired, large volumes of intravenous fluids needed to restore tissue perfusion may also be associated with the risk of increased accumulation of EVLW. The presented paper briefly reviews the mechanisms involved in lung edema formation and describes current options to measure EVLW. In addition, it discusses clinical implications of EVLW measurement in intensive care setting with particular focus on transpulmonary indicator dilution technique.

Capillary Permeability↗

PubMed1998

The effects of a polyacrylonitrile membrane and a membrane made of regenerated cellulose on the plasma concentrations of erythropoietin during hemodialysis.

In vitro studies have shown that some dialysis membranes significantly adsorb erythropoietin (EPO), a fact that might have an effect on anemia in long-term hemodialysis (HD) patients and on anemia treatment with recombinant human EPO. The purpose of the study was to determine whether the ability of adsorption demonstrated in vitro also has an effect on EPO concentrations in vivo. In a crossover study, the plasma concentrations of EPO were examined in 11 patients on chronic HD during HD using a polyacrylonitrile (AN69) membrane (high in vitro adsorption) plus EPO administered subcutaneously after the HD session, HD using a Cuprophan membrane (low in vitro adsorption) plus EPO administered subcutaneously after the HD session, HD using an AN69 membrane plus EPO administered subcutaneously after the HD session plus EPO administered intravenously immediately before HD, or HD using a Cuprophan membrane plus EPO administered subcutaneously after the HD session plus EPO intravenously immediately before HD. The intradialysis plasma concentrations of EPO (not detectable in the dialysate) determined at the dialyzer inlet and outlet at Minutes 5 and 240 of the procedure did not differ significantly after its subcutaneous administration from its predialysis concentrations with either the Cuprophan or AN69 membrane. A comparison of EPO concentrations between AN69 and Cuprophan did not reveal marked differences either. The course of concentrations after additional EPO intravenous administration was similar with no statistically demonstrable difference between the 2 membranes. In conclusion, under clinical conditions, AN69 and Cuprophan membranes do not differ in their effects on plasma EPO concentrations. The differences in EPO adsorption between AN69 and Cuprophan, demonstrated in vitro, do not seem to be of clinical importance.

Acrylic Resins↗