To increase blood pressure by improving contractility of the heart, which class of drugs should be given?

To increase blood pressure by improving contractility of the heart, administering positive inotropic drugs is the most effective approach. These drugs enhance the force of the heart's contraction, which directly contributes to increased cardiac output. This rise in cardiac output can lead to a higher blood pressure, especially in patients with conditions where the heart's pumping efficiency is compromised, such as heart failure.

Positive inotropic agents work by affecting the calcium levels in heart muscle cells, enhancing the contractile ability of the myocardium. By promoting stronger heart contractions, these medications support increased stroke volume and overall cardiac performance, ultimately contributing to systemic blood pressure elevation.

In contrast, negative inotropic drugs decrease the force of myocardial contractility, which would typically lower blood pressure rather than raise it. Alpha agonists primarily increase blood pressure through vasoconstriction rather than affecting myocardial contractility directly. Calcium channel blockers decrease calcium entry into the cells, leading to decreased myocardial contractility and reduced blood pressure. Thus, the use of positive inotropic drugs is essential when the goal is to elevate blood pressure by enhancing heart contractility.