Journal of critical care
-
Journal of critical care · Mar 1996
Comparative StudyA comparison between the acute effects of nitric oxide synthase inhibition and fluid resuscitation on myocardial function and metabolism in entotoxemic dogs.
Nitric oxide (NO) synthase inhibitors increase mean arterial pressure (MAP) and systemic vascular resistance (SVR) in animal models of sepsis and in humans with septic shock. However, NO synthase inhibitors may cause coronary vessel constriction leading to myocardial ischemia and increased mortality in endotoxemic animals. This study was designed to test the acute effect of NG-nitro-L-arginine (L-NAME) on left ventricular (LV) function and coronary blood flow in a dog model of endotoxemia. ⋯ We conclude that although L-NAME at 30 mg/kg causes vasoconstriction, its effects on coronary blood flow and LV function were not significant.
-
Nitric oxide (NO) is a major regulator of vascular tone, blood pressure, and blood flow, and plays a significant role in disease states associated with hemodynamic alterations. However, the role of NO in association with the effects of brain death (BD) has not yet been evaluated. ⋯ The decreases in pulmonary and systemic vascular resistance, pulmonary impedance, and cardiac function associated with BD are not related to major changes in the NO pathway. NO may not play a key role in the early changes after BD.
-
Journal of critical care · Mar 1996
Effect of alpha-adrenoreceptor stimulation on the diaphragmatic oxygen delivery-consumption relationship.
In the vascularly isolated canine hemidiaphragm, we tested the hypothesis that alpha-adrenoreceptor stimulation may influence diaphragmatic function and O2 extraction during reductions in O2 delivery (QO2di). ⋯ These results indicate that alpha-adrenoreceptor activation may increase the tension generated by the diaphragm as well as its oxygen consumption and oxygen extraction. Although this may be beneficial during moderate reductions in oxygen delivery, in more severe shock states, activation of these receptors by endogenous or exogenously administered catecholamines may hasten the development of delivery limitation of VO2di and compromise the ability to sustain ventilation.
-
Journal of critical care · Mar 1996
Partial liquid ventilation provides effective gas exchange in a large animal model.
The purpose of this study was to show the ability of partial liquid ventilation (PLV) to sustain gas exchange in normal large (50 to 70 kg) adult animals. ⋯ These data show that during PLV in this normal animal model, effective gas exchange is sustained and CT decreases with increasing perflubron dose.
-
The effective treatment of sepsis and septic shock has remained elusive despite intense research efforts. The tools of molecular biology have been applied to the problem of sepsis in an attempt to design more rational, directed therapy. Cellular interactions with invading microorganisms begin a series of stimulation events within the cell. ⋯ The measurement of cytokines is critically important to our understanding of their role in health and disease. Cytokines may be measured by either immunologic methods or biological assays. Molecular biology has made important contributions to our understanding of sepsis by precisely identifying some of the mediators and providing reagents for therapeutic use.