VF
The future is now. If you want your patient to walk out of the hospital, get them on ECMO and open up those coronaries - jshibata
HWN Suggests
VT, VF, and Electrical Storm
He has no pulse, so you start chest compressions. Initial rhythm is PEA so you give epinephrine and continue compressions as the patient is successfully intubated. The second rhythm shows ventricular fibrillation (VF). You think to yourself, “Great this guy might actually have a chance!” You’re feeling pretty good as you administer a shock and then resume compressions. It’s time for the next rhythm and pulse check, and the rhythm is still VF. You shock again, resume CPR, give epinephrine, and ask the nurse to pull up amiodarone 300mg as you anxiously await the next check. Rhythm is still VF.
Featured
High energy defibrillation
The use of a second defibrillator with separate pairs of electrodes allows 400 J of biphasic energy to be applied to depolarize a critical amount of myocardium. First described by in animal models by Geddes (4) in 1976, and then by Hoch (1) in 1994. He found that patients who developed refractory ventricular fibrillation during electrophysiology procedures had restoration of regular rhythm.
The Current State of Refractory VF
Given the difficulty in converting RVF to a perfusing rhythm, here are a few strategies beyond the standard therapy to add to your toolbox.
Esmolol in Refractory Ventricular Fibrillation
The evidence for esmolol in refractory Ventricular Fibrillation isn’t the greatest – no big RCTs to be certain. 500mcg/kg IV bolus followed by a drip of a maximum of 100mcg/kg/minunte
The 1st Community ECMO Program in the US
A small proportion of these patients will have refractory VF/VT OHCA not treatable by standard ACLS guidelines. One possible modality for these patients is extracorporeal membrane oxygenation (ECMO, followed by immediate coronary angiography and percutaneous coronary intervention (PCI). How would this ECMO-facilitated resuscitation strategy fair when applied in a US metropolitan community?
Articles of Interest
Esmolol for Refractory Ventricular Fibrillation
Dosing esmolol for refractory VF: 500mcg/kg bolus, followed by drip (max typically 1000 mcg/kg/min).
Esmolol for Refractory Ventricular Fibrillation (Still an option)
These refractory VF patients likely need a cardiac catheterization more than anything else. The more you can do in the ER to stabilize them to revascularization of the vessel that precipitated their refractory VF electrical storm, the better. Esmolol should be a strong consideration in these rare situations.
Management of Electrical Storm
Electrical storm is frequently associated with a catecholamine surge, either as the cause of the arrythmias, or as a result of the frequent shocks and underlying etiology. Treatment is aimed at counteracting that sympathetic tone, which includes analgesia, sedation, and beta-blockers.
Treatment Strategies for Shock-Resistant Ventricular Fibrillation
Esmolol is the only drug in the management of cardiac arrest that has shown an increased rate of survival to hospital discharge with favorable neurologic outcomes. Albeit in a small study, patients who received esmolol after three defibrillations and 3 mg of epinephrine had a 50 percent survival to hospital discharge with a favorable neurologic outcome compared to 11 percent of patients who did not receive esmolol.4
Ultrasound-Guided Stellate Ganglion Block in Pulseless Refractory Ventricular Fibrillation
Stellate ganglion blockade has been used for over a century to decrease sympathetic tone to the heart.
Resources
Beyond ACLS: Dual Simultaneous External Defibrillation
For those of us in the trenches of the emergency department, we have to think beyond ACLS at times. Although VF typically responds very well to the standard energies of defibrillation, maybe in patients with higher body mass index or morbid obesity we need higher energies to achieve successful defibrillation.
