Ensuring adequate circulation to sustain life (Algorithm 3) Ensuring adequate circulation to sustain life (Algorithm 3). CPR, cardiopulmonary resuscitation; LVAD, left ventricular assist device; VF, ventricular fibrillation; VT, ventricular tachycardia. Ensuring adequate circulation to sustain life (Algorithm 3). CPR, cardiopulmonary resuscitation; LVAD, left ventricular assist device; VF, ventricular fibrillation; VT, ventricular tachycardia. Christopher T Bowles et al. Emerg Med J 2017;34:842-850 Copyright © BMJ Publishing Group Ltd and the College of Emergency Medicine. All rights reserved.