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The effect of epinephrine on peripheral circulation was studied in ten anesthetized open-chest dogs. Blood flow and right atrial pressure were independently controlled by a right heart bypass; changes in blood volume could be precisely determined from the changes occurring in the bypass reservoir. At constant blood flow and right atrial pressure, a constant infusion of epinephrine (5.8 Mg/kg min" 1 ) decreased blood volume by an average of 208 ml. During epinephrine infusion, the ratio of changes in blood volume to changes in blood flow measured at constant right atrial pressure, (A V/A0)p ra , decreased from 0.226 minutes to 0.153 minutes and the ratio of changes in blood volume to changes in right atrial pressure at constant blood flow, the vascular compliance, decreased from 27.1 ml/cm H 2 O to 20.7 ml/cm H 2 O. Transient changes in blood volume following a step decrease in right atrial pressure at constant blood flow showed that blood was draining from two vascular compartments with different time constants: 0.059 minutes and 0.388 minutes before epinephrine infusion and 0.058 minutes and 0.486 minutes during epinephrine infusion. We analyzed the data using a mathematical model of the peripheral circulation consisting of two compartments with different time constants. The analysis showed that the primary effect of epinephrine on the systemic circulation was to redistribute blood flow away from the compartment with the longest time constant. The reduction in (&VI&Q) Pra and the decrease in blood volume at constant flow and right atrial pressure were essentially determined by the change in flow distribution brought about by a change in arteriolar tone and not by a change in venous tone. KEY WORDS peripheral circulation vascular compliance cardiac output circulatory model venous resistance mean circulatory pressure venous return• For well over a hundred years, it has been recognized that the level of cardiac output is determined not only by the state of the heart but also by the state of the blood vessels (1,2). Grodins (3) has succinctly stated the reason behind this phenomenon: "... mechanical coupling between heart and circuit dictates that cardiac output is a function of both heart and circuit parameters." Guyton (4) has explained this relationship in more detail. The pressure of blood within the right atrium plays a unique role in the coupling between heart and blood vessels. On the one hand, the level of right atrial pressure relative to intrapleural pressure determines the filling pressure of the right ventricle. Therefore, right

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There would need to be much more research performed to determine if this agent had a role as a chemotherapy agent; however, health care professionals should be aware of itraconazole's potential antineoplastic mechanisms.

SCOFs significantly reduced serotonin antagonist anti-emetic cost and prescribing error rate over a four-month period.

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The complexity of cancer chemotherapy requires pharmacists be familiar with the complicated regimens and highly toxic agents used. This column reviews various issues related to preparation, dispensing, and administration of antineoplastic therapy, and the agents, both commercially available and investigational, used to treat malignant diseases.