The effect of angiotensin II on blood pressure in patients with circulatory shock: a structured review of the literature

Abstract

BackgroundCirculatory shock is a common syndrome with a high mortality and limited therapeutic options. Despite its discovery and use in clinical and experimental settings more than a half-century ago, angiotensin II (Ang II) has only been recently evaluated as a vasopressor in distributive shock. We examined existing literature for associations between Ang II and the resolution of circulatory shock.MethodsWe searched PubMed, MEDLINE, Ovid, and Embase to identify all English literature accounts of intravenous Ang II in humans for the treatment of shock (systolic blood pressure [SBP] ≤ 90 mmHg or a mean arterial pressure [MAP] ≤ 65 mmHg), and hand-searched the references of extracted papers for further studies meeting inclusion criteria. Of 3743 articles identified, 24 studies including 353 patients met inclusion criteria. Complete data existed for 276 patients. Extracted data included study type, publication year, demographics, type of shock, dosing of Ang II or other vasoactive medications, and changes in BP, lactate, and urine output. BP effects were grouped according to type of shock, with additional analyses completed for patients with absent blood pressure. Shock was distributive (n = 225), cardiogenic (n = 38), or from other causes (n = 90). Blood pressure as absent in 18 patients.ResultsFor the 276 patients with complete data, MAP rose by 23.4% from 63.3 mmHg to 78.1 mmHg in response to Ang II (dose range: 15 ng/kg/min to 60 mcg/min). SBP rose by 125.2% from 56.9 mmHg to 128.2 mmHg (dose range: 0.2 mcg/min to a 1500 mcg bolus). A total of 271 patients with complete data were determined to exhibit a BP effect which was directly associated with Ang II. Subgroups (patients with cardiogenic, septic, and other types of shock) exhibited similar increases in BP. In patients with absent BP, deemed to be cardiac arrest, return of spontaneous circulation (ROSC) was achieved, and BP increased by an average of 107.3 mmHg in 11 of 18 patients. The remaining seven patients with cardiac arrest did not respond.ConclusionsIntravenous Ang II is associated with increased BP in patients with cardiogenic, distributive, and unclassified shock. A role may exist for Ang II in restoring circulation in cardiac arrest.Electronic supplementary materialThe online version of this article (doi:10.1186/s13054-017-1896-6) contains supplementary material, which is available to authorized users.

Outcomes in Patients with Vasodilatory Shock and Renal Replacement Therapy Treated with Intravenous Angiotensin II

“…This could be due in part to the fact that the kidneys may be particularly susceptible to the effects of perfusion pressure to maintain blood flow ( 21 ). In this regard, ATHOS-3 ( 19 ), the parent trial of this analysis, and previous clinical and case studies ( 8 , 22 – 25 ) consistently demonstrated that synthetic angiotensin II can increase blood pressure in patients with shock. However, the salutary effect of angiotensin II may also be due to a mechanistic link beyond perfusion alone.…”

Angiotensin II for the emergency physician

“…The first reported case series of Ang-2 in humans was published in 1961, and for over 35 years, a bovine version of Ang-2 was produced for the treatment of shock 2. One systematic review assessing 353 patients in 24 studies from 1960 to 2017 examined the blood pressure effects of Ang-2 in patients with hypotension 13. Uniformly, Ang-2 significantly raised blood pressure for cardiogenic, distributive and undifferentiated shock.…”

“…Moreover, the utility of Ang-2 outside the realm of distributive shock requires further investigation. While some case reports describe the use of Ang-2 in cardiac arrest and cardiogenic shock, additional randomised controlled trials to rigorously examine the efficacy in these populations are needed 2 13. Finally, although the FDA does not comment on its use without other vasopressors, further studies addressing the use of Ang-2 as a single agent are also warranted, given the nature of the ATHOS-3 trial.…”

Angiotensin in ECMO patients with refractory shock

“…Patients receiving renal replacement therapy also had improved survival and faster recovery of renal function [ 2 ]. Recent literature noted the potential role of Ang II in other types of shock [ 3 ].…”