Vasopressor

Vasopressors are a class of medications that elevate blood pressure by constricting blood vessels. They are used to treat clinically significant hypotension and shock, particularly after adequate fluid resuscitation has been attempted or when fluid therapy fails to restore tissue perfusion.

Most vasopressors act on alpha-adrenergic receptors to cause vasoconstriction and increased systemic vascular resistance; some also increase cardiac output via beta-1 receptor stimulation, while others such as vasopressin act on non-adrenergic pathways.

Common vasopressors include norepinephrine, epinephrine, phenylephrine, vasopressin, and dopamine. In practice, norepinephrine is often the first-line pressor in septic shock; phenylephrine is used when tachycardia is unfavorable; vasopressin may be added as an adjunct; dopamine is used selectively for its inotropic effects.

Administration and monitoring involve continuous IV infusion, usually via a central line, and titration to maintain a target mean arterial pressure or adequate organ perfusion. Patients are monitored for arterial pressure, urine output, lactate levels, and signs of improved or deteriorating perfusion.

Risks include tissue injury from extravasation, arrhythmias, hypertension, reduced regional blood flow, and impaired peripheral perfusion. Careful line management, dosing, and monitoring help minimize harm.