J Trauma
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The purpose of this study was to determine how chronic cocaine exposure affects the hemodynamic response to epinephrine, dopamine, phenylephrine, and ephedrine in awake sheep. ⋯ In awake sheep, chronic cocaine exposure markedly impairs the hemodynamic response to dopamine but not to epinephrine, phenylephrine, or ephedrine.
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Bomb blast survivors are occasionally found in profound shock and hypoxic without external signs of injury. We investigated the cardiovascular and pulmonary responses of rats subjected to a blast pressure wave. ⋯ Blast-induced circulatory shock resulted from immediate myocardial depression without a compensatory vasoconstriction. Hypoxia presumably resulted from a ventilation-perfusion mismatch caused by pulmonary hemorrhage.
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Prehospital guidelines for the treatment of penetrating trauma recommend rapid volume resuscitation to normal blood pressure. There is evidence, however, that fluid resuscitation to normal blood pressure in the setting of uncontrolled hemorrhagic shock (UHS) causes increased bleeding, hemodilution, and mortality. To test this hypothesis, we evaluated the effects of blood pressure and hemodilution on survival in a rat model of UHS. ⋯ The effects of blood pressure alone, hemodilution alone, and their interaction were significantly related to base deficit and arterial pH. Hemodilution, but not blood pressure as an end point in resuscitation, was significantly related to lactate levels. The high mortality in this model of uncontrolled hemorrhage was attributable to the effects of blood pressure, hemodilution, and the interaction between the two variables, rather than simply continued blood loss from increased hydrostatic pressure.