BRASH Syndrome: A Vicious Cycle

BRASH syndrome is an uncommon but often fatal condition in which an acute renal injury initiates a vicious cycle of bradycardia, hyperkalemia, hypotension and worsening renal failure in patients who take AV-nodal blocking medications.

BRASH syndrome: more than just syncope

The pentad of bradycardia, renal failure, atrioventricular nodal blockade, shock, and hyperkalemia describes the BRASH syndrome, a newly recognized phenomenon in which accumulation of potassium and renally excreted atrioventricular nodal blockers cause a cycle of bradycardia, hypoperfusion, and worsening renal function.

Bradycardia, Renal Failure, Atrioventricular Nodal Blockade, Shock and Hyperkalemia Syndrome Involving Digoxin Toxicity: A Case Report

BRASH syndrome is a clinical entity requiring prompt diagnosis for life-saving treatment, including renal replacement therapy, vasoactive medications, transvenous pacing, and reversing agents, when appropriate.

BRASH Syndrome

BRASH syndrome is a combination of Bradycardia, Renal failure, AV(atrioventricular) nodal blockade, Shock, and Hyperkalemia. It is clinically essential to take these manifestations as a syndrome rather than isolated findings because they are interrelated and have synergistic effects. The most common error in managing BRASH syndrome is focusing on a single component of the syndrome (e.g. hyperkalemia) meanwhile, other aspects of the syndrome are overlooked.

BRASH Syndrome – Diagnosis and Treatment

Characterized by profound bradycardia out of proportion to the degree of hyperkalemia or use of AV node blocking medication. If untreated, it can progress to shock and multi-organ failure. This is a rare clinical syndrome recently described in multiple case reports.

BRASH syndrome: an emerging emergency

In patients with syncope, BRASH syndrome should be considered when bradycardia is associated with hyperkalaemia, without classic ECG changes, along with a history of AVN blocker use. It is important to recognise so that appropriate therapy can be instituted that addresses all the elements of the syndrome, rather than focusing on a single component.

BRASH syndrome: Bradycardia, Renal failure, Av blocker, Shock, Hyperkalemia

The treatment of BRASH syndrome centers around aggressive therapy for hyperkalemia. Additionally, many patients require a catecholamine infusion to support their perfusion.

EMNote

BRASH syndrome may present with heterogeneous, nonspecific symptoms, including generalized weakness, dizziness, and syncope, which could be easily misdiagnosed if clinicians are unaware of the association between AV nodal blocking agents and the possible consequences of bradycardia, renal injury, and shock. Cardiac pacing is rarely needed.

Episode 89- Let’s talk BRASH

Remember that this syndrome is dependent on the synergistic effects of AKI, taking an AV-nodal blocker, and hyperkalemia—typically neither one of these by itself would cause the constellation of symptoms that we see. This is evidenced by ½ of all patients not having a severe hyperkalemia or a severe enough AKI to cause circulatory shock alone. It also doesn’t fit with pure AV-node blocker toxicity since patients report taking their meds as directed.

Rare presentation of BRASH syndrome with hypoglycemia and altered mental status

Patients with BRASH syndrome can present with diverse signs and symptoms and are usually in critical condition, but if recognized early, the syndrome is treatable and may have a favorable prognosis.