Journal of critical care
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Journal of critical care · Sep 1997
Dobutamine maintains intestinal villus blood flow during normotensive endotoxemia: an intravital microscopic study in the rat.
The gut plays a pivotal role in sepsis. Intestinal hypoperfusion with subsequent ischemia leads to translocation of endotoxin. Dobutamine has been demonstrated to increase mesenteric blood flow during endotoxic shock; however, its effects on mucosal blood flow especially in intestinal villi is not known. Therefore, we investigated its influence on the blood flow and the arteriolar diameters in intestinal villi in a model of normotensive endotoxemia. ⋯ Our results indicate that in rats with normotensive endotoxemia, arteriolar diameters and blood flow in intestinal villi were reduced. Dobutamine prevented arteriolar constriction and maintained villus blood flow at preendotoxemic values.
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Journal of critical care · Jun 1997
Randomized Controlled Trial Comparative Study Clinical TrialPositive pressure inspiration differentially affects right and left ventricular outputs in postoperative cardiac surgery patients.
The purpose of this study was to determine the dynamic changes in right ventricular (RV) and left ventricular (LV) output during positive airway pressure inspiratory hold maneuvers so as to characterize the interaction of processes in creating steady-state cardiac output during positive pressure ventilation. ⋯ Positive pressure inspiration induces time-dependent changes in central hemodynamics, which are dissimilar between RV and LV function. Initially, inspiration increases RV output but decreases LV output, such that intrathoracic blood volume increases. However, sustained inspiratory pressures induce proportionally similar decreases in both RV and LV outputs. Thus, the hemodynamic effects of positive pressure ventilation will depend on the degree of lung inflation, the inspiratory time, and when measurements are made within the ventilatory cycle. These data also suggest that positive pressure ventilation with up to 20 cm H2) P(aw) does not significantly impair ventricular performance in humans.
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Journal of critical care · Jun 1997
Randomized Controlled Trial Comparative Study Clinical TrialGastric intramucosal pH changes after volume replacement with hydroxyethyl starch or crystalloid in patients undergoing elective abdominal aortic aneurysm repair.
Gastric intramucosal pH (pHi), a surrogate marker of tissue oxygenation, falls following abdominal aorta aneurysm (AAA) repair. We tested the hypothesis that volume replacement with a hydroxyethyl starch solution would result in better preserved splanchnic oxygenation than would volume replacement with crystalloid solutions. ⋯ In patients undergoing major surgery, volume resuscitation with hydroxyethyl starch solutions may improve microvascular blood flow and tissue oxygenation.