Angiotensin II: A New Vasopressor for the Treatment of Distributive Shock

Angiotensin II (ATII) is a potent endogenous vasoconstrictor that has recently garnered regulatory approval for the treatment of distributive shock, including septic shock. Traditional vasoactive substances used in the management of distributive shock include norepinephrine, epinephrine, phenylephrine, and vasopressin. However, their use can be associated with deleterious adverse drug effects, such as splanchnic vasoconstriction and associated hypoperfusion. The purpose of this review is to describe ATII, including its pharmacologic mechanisms, pharmacokinetic profile, evidence of efficacy and tolerability, and potential role in contemporary critical care practice.

Peer-reviewed clinical trials and relevant treatment guidelines published from 1966 to September 14, 2019, were identified from Medline/PubMed using the following search terms: angiotensin II OR angiotensin 2 AND shock OR septic shock OR vasodilatory shock. Pertinent review articles were reviewed for additional studies for inclusion and discussion. The final decision on the inclusion of studies in the current review was based on the expert opinion of the authors.

On the basis of the available evidence, ATII is effective at elevating blood pressure in patients with distributive shock and appears to reduce the dose of concurrent vasopressors to maintain adequate blood pressure. ATII has been investigated for other causes of shock; however, robust evidence of off-label indications is lacking and is much needed. Clinical and cost benefits compared with traditional vasopressors have yet to be established.

ATII represents a welcome addition to the armamentarium of critical care clinicians. Enthusiasm for the use of ATII should be balanced with the current gaps in our understanding of ATII in patients with shock. Until further evidence provides more clinically meaningful benefits, as well as cost-effectiveness compared with currently available vasopressors, critical care clinicians should reserve ATII for salvage therapy in patients with septic shock.