Vasoactive medications and inotropic agents are utilized frequently in the pediatric intensive care unit for patients in various states of shock. Selecting the proper pharmacologic therapy requires knowledge of the mechanism of action of each medication, as well as the etiology of the patient’s physiologic derangement.
TABLE 30-1
Receptor Classes
| Receptor | Cardiac Effects | Arterioles | Venules |
| Alpha | None | Coronary, skeletal muscle, pulmonary, abdominal viscera, and renal vasoconstriction | Systemic vein vasoconstriction |
| Beta1 | Increase heart rate (S-A node), increase contractility and conduction velocity (atria and A-V node) | None | None |
| Beta2 | Increase in ventricle contractility and conduction velocity | Coronary, skeletal muscle, pulmonary, abdominal viscera, and renal vasodilatation | Systemic vein vasodilatation |
| Dopamine | None | Coronary, renal, cerebral, mesenteric vasodilation | Regional vasodilation |
