Critical care medicine
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Critical care medicine · Jun 1997
Measurements of total plasma nitrite and nitrate in pediatric patients with the systemic inflammatory response syndrome.
The systemic inflammatory response syndrome (SIRS) is typified by the presence of fever, hemodynamic changes, and end organ dysfunction. Endothelial cell activation leads to overproduction of nitric oxide, which results in sustained vasodilation and hypotension. This study was undertaken to determine the sensitivity, specificity, and positive and negative predictive values of plasma nitrite/nitrate measurements in identifying patients with clinical characteristics of SIRS, as defined by criteria based on physician diagnosis. ⋯ Clinical diagnosis of SIRS is strongly associated with increased total plasma nitrite/nitrate concentrations in pediatric patients in the pediatric ICU. Many patients with increased nitrite/nitrate concentrations have inflammation without having a clinical diagnosis of SIRS. Our data suggest that increased plasma nitrite/nitrate concentrations are the standard for identifying patients with inflammation in the pediatric ICU.
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Critical care medicine · Jun 1997
Delayed hyperemia causing intracranial hypertension after cardiopulmonary resuscitation.
To clarify whether early or delayed failure of cerebral perfusion after cardiopulmonary resuscitation (CPR) occurs in humans and contributes to secondary brain damage. ⋯ Delayed hyperemia occurs in humans after resuscitation from cardiac arrest. Our data suggest that this delayed hyperemia can lead to intracranial hypertension and occasionally acute brain swelling, contributing to a poor outcome. A high mean flow velocity of the middle cerebral artery with a low ratio of mean flow velocity of the middle cerebral artery to mean flow velocity of the internal carotid artery may be predictive of critical hyperemia. As an indirect method of measuring cerebral blood flow transcranial Doppler sonography can be used to adjust treatment for failure of cerebral perfusion after resuscitation.
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Critical care medicine · Jun 1997
Effects of carboxy-PTIO on systemic hemodynamics, liver energetics, and concentration of liver metabolites during endotoxic shock in rabbits: a 31P and 1H magnetic resonance spectroscopic study.
To investigate the effects of 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO), a nitric oxide scavenger, on the lipopolysaccharide-induced hypotension, hepatocellular dysfunction, and liver damage in endotoxic rabbits. ⋯ The results of this study indicate that the infusion of carboxy-PTIO: a) prevented the delayed hypotension associated with endotoxic shock in rabbits; b) returned the hepatocellular ATP concentrations nearly to the level of the controls and alleviated hepatocellular acidosis; c) normalized various hydrophilic metabolites, such as lactate and alanine in the liver; and d) did not exacerbate liver injury after the administration of lipopolysaccharide. These findings indicate that carboxy-PTIO, a nitric oxide scavenger, may have a positive vasopressor effect during hypodynamic septic shock without exacerbating liver injury.
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Critical care medicine · Jun 1997
Randomized Controlled Trial Clinical TrialOxygen transport patterns in patients with sepsis syndrome or septic shock: influence of treatment and relationship to outcome.
To investigate the relationship between oxygen transport patterns and outcome in patients with sepsis syndrome or septic shock managed according to two different treatment regimens. ⋯ Survivors of sepsis syndrome or septic shock are characterized by an ability to increase both DO2 and VO2. In contrast, nonsurvivors typically have reduced cardiac reserve, they fail to increase VO2 following resuscitation, and when delivery is enhanced with aggressive inotropic support, oxygen extraction falls. These patterns of response were similar in both treatment and control groups, although the magnitude of the changes was exaggerated in the treatment group. These observations may help to explain the findings by some investigators that treatment aimed at achieving survivor values of cardiac index, DO2, and VO2 fails to improve outcome when instituted following admission to intensive care.
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Critical care medicine · Jun 1997
Randomized Controlled Trial Clinical TrialEffects of varying levels of positive end-expiratory pressure on intracranial pressure and cerebral perfusion pressure.
To determine the influence of positive end-expiratory pressure (PEEP) on intracranial pressure and cerebral perfusion pressure. ⋯ In patients with normal intracranial pressure, PEEP at 5 cm H2O did not significantly alter intracranial pressure. The clinical relevance of the intracranial pressure increase at PEEP levels of 10 and 15 cm H2O is questionable because cerebral perfusion pressure did not change and remained > 60 mm Hg. In patients with increased intracranial pressure, higher levels of PEEP did not significantly change intracranial pressure or cerebral perfusion pressure.