Analysis of the Multiple Effects of Vasoactive and Positive Inotropic Agents on Cardiovascular System Variables

Hypertension in patients following coronary artery surgery is commonly treated with manually administered sodium nitroprusside (SNP) infusion based on a single variable, either mean arterial pressure (MAP) or peak systolic pressure.2, 3, 5, 12, 13 This practice fails to take account of the effects of systemic resistance changes, blood volume redistribution, and possible reflex responses upon aortic blood flow (FLO) and therefore cardiac output. The interactions between these and other variables may be undesirable in the management of critically ill patients. This study was made to further delineate the responses of the cardiovascular system variables to sodium nitroprusside (SNP), epinephrine (EPI) and dopamine (DOP).