Antioxidant therapy in intensive care.

Purpose Of Review: This review intends to summarize the recent findings regarding the presence of increased oxidative stress in critically ill patients and its potential pathophysiologic role, as well as the results of recent clinical trials of antioxidant therapies.

Recent Findings: Several lines of evidence confirm the increase in oxidative stress during critical illness. The oxidative damage to cells and tissues eventually contributes to organ failure.

Ischemic stroke and splenic rupture in a case of Streptococcus bovis endocarditis.

A 58-year-old man with an acute stroke suffered from splenic rupture. Streptococcus bovis was found in blood cultures, and gram-negative cocci were found in the infarcted spleen. Hemorrhagic transformation of the stroke occurred.

Hemodynamic effects of glibenclamide during endotoxemia: contrasting findings in vitro versus in vivo.

The final common pathway involved in the cardiovascular alterations of septic shock is incompletely defined. The opening of KATP channels is associated with vasorelaxation and alterations in cardiac contractility. This event may be triggered during septic shock by increased nitric oxide (NO) production, by a decreased intracellular content of ATP, or by a change in the transmembrane electrical potential.

Nutritional papers in ICU patients: what lies between the lines?

The abundance of literature related to nutritional support reflects its recently recognised role in preventing metabolic complications and gut dysfunction during critical illness. However, some published studies lack relevance to critically ill patients, as a result of the selection of subjects and outcome variables, or flaws in the study design, as well as in the type, composition, timing, route of administration and amount of nutritional support given. This review will highlight these confounding factors by describing two imaginary (but typical) clinical trials and by analysing some studies published.

Monocyte CD40 expression in severe sepsis.

D40 is a cell surface protein belonging to the tumor necrosis factor (TNF) receptor family. Ligation of monocyte CD40 by the T cell-derived CD40 ligand can trigger the production of various mediators, the transcription and activation of enzymes, and the upregulation of costimulatory molecules involved in the pathogenesis of sepsis. To test the hypothesis that CD40 is expressed on the surface of monocytes during sepsis, we measured CD40 expression by flow cytometry on freshly sampled monocytes from 40 patients with severe sepsis, including 15 patients with bacteremia, and from eight healthy volunteers.

Does aprotinin influence the inflammatory response to cardiopulmonary bypass in patients?

Objectives: Aprotinin has been shown to have anti-inflammatory properties, but its effects on the inflammatory reaction to cardiopulmonary bypass remain controversial. This prospective, randomized, double-blind study evaluated the influence of aprotinin on various blood markers of inflammation during and after cardiopulmonary bypass.

Methods: Sixty male patients underwent coronary artery bypass grafting.

Position paper of the ESICM Working Group on Nutrition and Metabolism. Metabolic basis of nutrition in intensive care unit patients: ten critical questions.

The metabolic changes associated with critical illness involve several pathways acting at different steps of the utilization of nutritive substrates. The understanding of the role of these pathways and of their complex regulation has led to the development of new strategies for the metabolic and nutritional management of critically ill patients, including the development of new products for nutritional support. The rationale for changing the profile of nutritional support solutions by adding novel substrates is also discussed.

Does methylene blue administration to septic shock patients affect vascular permeability and blood volume?

Objective: To assess the effects of the inhibition of guanylate cyclase, an enzyme involved in sepsis-related vascular and myocardial dysfunctions, on hemodynamic variables including blood volume and pulmonary vascular permeability during septic shock.

Design: Prospective, open study with repeated measurements.

Setting: A medicosurgical intensive care unit of a university hospital.

Tight control of glycaemia in critically ill patients.

Purpose Of Review: This manuscript attempts to review the effects associated with hyperglycaemia in critically ill patients and the effects of various insulin regimens. The available clinical findings and pertinent experimental data are examined.

Recent Findings: Intensive insulin therapy titrated to maintain blood glucose level between 4.

Microvascular blood flow is altered in patients with sepsis.

Microvascular blood flow alterations are frequent in animal models of sepsis and may impair tissue oxygenation. We hypothesized that alterations of the microcirculation are present in patients with sepsis. We used an orthogonal polarization spectral imaging technique to investigate the sublingual microcirculation in 10 healthy volunteers, 16 patients before cardiac surgery, 10 acutely ill patients without sepsis (intensive care unit control subjects), and 50 patients with severe sepsis.

European Society of Intensive Care Medicine 14th annual congress, 30 September-3 October 2001, Geneva, Switzerland.

The European Society of Intensive Care Medicine Annual Congress offers the opportunity for basic scientists and clinicians to share recent findings. Apart from the large number of free communications, several sessions of the congress were dedicated to state-of-the-art tutorials given by established speakers. The areas of interest of the attendees were widely distributed as usual, a reflection of the large array of so-called 'critical illnesses'.

Metabolic effects of arginine addition to the enteral feeding of critically ill patients.

Background: Some studies have suggested that the addition of arginine to enteral feeding solutions may improve outcome in critically ill patients, but the mechanism is incompletely explained. In particular, the availability and utilization of arginine administered enterally is not well defined.

Methods: This prospective, randomized, double-blind, placebo-controlled study performed in a Department of Medicosurgical Intensive Care included 51 patients likely requiring long-term enteral feeding.

Time course of inducible nitric oxide synthase activity following endotoxin administration in dogs.

An increased production of nitric oxide (NO) via the inducible isoform of NO synthase (iNOS) has been incriminated in the pathogenesis of septic shock. Since the time course of iNOS activity is not known during endotoxic shock in dogs, we measured iNOS activity, estimated by the rate of conversion of (14)C-arginine to (14)C-citrulline in the absence of calcium, in the heart, lung, liver, kidney, and gut at 1, 2, 3, 4, and 6 h after a bolus of Escherichia coli endotoxin (2 mg/kg, iv), in the dog. This model, including generous fluid administration, is associated with typical features of human septic shock, including low systemic vascular resistance, altered myocardial function and limited oxygen extraction capability.

Enteral feeding with a solution enriched with antioxidant vitamins A, C, and E enhances the resistance to oxidative stress.

Objective: To assess whether dietary supplementation with the antioxidant vitamins A, C, and E enhances parameters of oxidative stress and influences the course of critically ill patients.

Design: Prospective, randomized, double-blinded, placebo-controlled study.

Setting: Department of medicosurgical intensive care of an academic hospital.

Hemodynamic responses to successful weaning from mechanical ventilation after cardiovascular surgery.

Weaning from mechanical ventilation is usually associated with an increase in oxygen consumption (VO2), which may stress the cardiovascular system. We studied relative changes in the cardiac index and oxygen extraction ratio (EO2) during successful weaning in patients after cardiac surgery (n = 52), cardiac transplantation (n = 17), or abdominal aortic surgery (n = 11). Cardiac index was determined by the thermodilution technique and arterial and mixed venous blood gases were obtained before and 30 min after the start of weaning through a T-piece.

Effects of nitric oxide in septic shock.

Nitric oxide (NO) is believed to play a key role in the pathogenesis of septic shock, although many aspects of NO's involvement remain poorly defined. Recent years have seen advances in our understanding of the production and effects of NO, but much of the work has been done in animal models and may not be directly relevant to the clinical situation. Differences between species and models can account for many of the apparently conflicting results obtained.

Management of the critically ill patient with severe sepsis.

Sepsis is a common cause of morbidity and mortality among the critically ill patient population. However, no anti-sepsis therapy has yet been found to be effective and treatment is thus largely supportive. Adequate fluid resuscitation must be accompanied by effective ventilation, and adrenergic agents may be needed to restore perfusion pressure and improve myocardial function.

Enteral nutrition in intensive care patients: a practical approach.

Severe protein-calorie malnutrition is a major problem in many intensive care (ICU) patients, due to the increased catabolic state often associated with acute severe illness and the frequent presence of prior chronic wasting conditions. Nutritional support is thus an important part of these patient's management. Over the years, enteral nutrition (EN) has gained considerable popularity, due to its favorable effects on the digestive tract and its lower cost and rate of complications compared to parenteral nutrition.

Management of nutrition in European intensive care units: results of a questionnaire. Working Group on Metabolism and Nutrition of the European Society of Intensive Care Medicine.

Objective: To describe the practical aspects of nutritional management in intensive care units (ICUs).

Design: A 49-item questionnaire was sent to the physician members of the European Society for Intensive Care Medicine. The issues addressed included: medical environment, assessment of nutritional status and current practice for enteral and parenteral nutrition.

Isoflavone-mediated inhibition of tyrosine kinase: a novel antiinflammatory approach.

Tyrosine kinase (TK)-mediated phosphorylation regulates signal transduction pathways resulting in the expression of a variety of inflammatory genes. Inhibition of TK activity in vivo has been shown to increase survival in a lethal model of murine endotoxemia, suggesting a novel therapeutic approach to inflammation and circulatory shock. We examined the role of TK activity on the expression of the inducible nitric oxide (NO) synthase (iNOS).

The metabolic fate of long-term inhaled nitric oxide.

Purpose: The fate of inhaled nitric oxide (NO) has not been precisely defined in critically ill patients. This study aimed at defining the effects of long-term NO inhalation on circulating NO byproduct levels.

Material And Methods: During NO therapy, plasma and urine from 13 critically ill patients were sampled daily for determination of the stable byproducts of NO (nitrite [NO2-] and nitrate [NO3-].

Enteral nutrition in intensive care patients: a practical approach. Working Group on Nutrition and Metabolism, ESICM. European Society of Intensive Care Medicine.

Severe protein-calorie malnutrition is a major problem in many intensive care (ICU) patients, due to the increased catabolic state often associated with acute severe illness and the frequent presence of prior chronic wasting conditions. Nutritional support is thus an important part of the management of these patients. Over the years, enteral nutrition (EN) has gained considerable popularity, due to its favorable effects on the digestive tract and its lower cost and rate of complications compared to parenteral nutrition.