UMEM Educational Pearls

The BRASH syndrome (Bradycardia, Renal failure, AV nodal blockade, Shock, Hyperkalemia) has been increasingly described in the literature in the past 3-5 years.  

The inciting factor is generally considered to be something that prompts acute kidney injury, often hypovolemia of some sort.  Rather than AV nodal blocker overdose or severe hyperkalemia causing conduction problems, the combination of AV nodal blocker use (most often beta-blockers, but can be any type) and hyperkalemia (often only moderate) has a synergistic effect on cardiac conduction with ensuing bradycardia that can devolve into a cycle of worsening renal perfusion and shock.

Treatment is supportive, but most effective when the syndrome is recognized and all parts simultaneously managed.  ED physicians should be familiar with its existence for targeted whole-syndrome stabilization and to avoid diagnostic delay.

  • Shock – If hypovolemic, IV fluid resuscitation. Concomitantly or if still hypotensive, epinephrine infusion is recommended as it provides both chronotropy and inotropy, and also assists with hyperkalemia.
  • Hyperkalemia – usually mild/moderate; IV calcium for any ECG abnormalities, intracellular shifting medications, and kaliuresis (may require high-dose loop diuretics, with IV fluids if needed to maintain volume)
  • Bradycardia – will usually respond to IV calcium and chronotropy (epinephrine, isoproterenol); pacing rarely but sometimes needed
  • Renal failure – IVF and perfusion support as noted above, but patients may require dialysis if renal failure is severe and hyperkalemia is unable to be medically managed

References

  1. Shah P, Gozun M, Keitoku K, et al. Clinical characteristics of BRASH syndrome: Systematic scoping review. Eur J Intern Med. 2022 Sep;103:57-61. doi: 10.1016/j.ejim.2022.06.002. 
  2. Farkas JD, Long B, Koyfman A, Menson K. BRASH Syndrome: Bradycardia, Renal Failure, AV Blockade, Shock, and Hyperkalemia. J Emerg Med. 2020 Aug;59(2):216-223. doi: 10.1016/j.jemermed.2020.05.001.