In this study we have evaluated the effects of the pressure and volume components of myocardial work on survival in cardiogenic shock. Experimental cardiogenic shock was produced in dogs by a modification of a method first described by Agress.1 Quantitative changes in blood pressure, cardiac output, peripheral resistance, and myocardial work were obtained in a group of control dogs before and after the production of shock. Similar hemodynamic measurements were obtained in groups of dogs receiving vasopressor, vasodilator, or volume expansion therapy. The survival rate in each group was compared to the control group and related to the pressure and volume components of myocardial work.
Materials and Methods
Mongrel dogs weighing between 10 and 20 kg were premedicated with intramuscular injections of morphine sulfate (1 mg/kg of body weight). The dogs were anesthetized with intravenous sodium thiamylal to the depression of the corneal reflex. An endotrachial airway was inserted