Abstract 13922: Echocardiography During Resuscitation: A Paradox of Right Ventricular Dilatation in Cardiac Arrest Caused by Hypovolemia and Hyperkalemia - A Randomized Porcine Study
Introduction: The interpretation of echocardiographic findings from patients with spontaneous circulation is often extrapolated to cardiac arrest. In patients with spontaneous circulation, severe hypovolemia causes a reduction in right ventricular (RV) diameter, which may persist during cardiac arrest. In contrast, hyperkalemia may cause RV dilation by arresting the heart in diastole. Also, animal studies have demonstrated RV dilation in ventricular fibrillation (VF).
Aim: To study the RV diameter during resuscitation from cardiac arrest caused by hypovolemia and hyperkalemia, compared to VF as control.
Methods: Twenty-four pigs were randomized to 7 min. of cardiac arrest induced by hypovolemia, hyperkalemia, or VF. Animals were resuscitated in accordance with the AHA 2010 Advanced Life Support guidelines. Echocardiographic images were obtained before and during cardiac arrest. Primary endpoint: RV diameter at the third rhythm analysis.
Results: In the hypovolemia group, an initial decrease in RV diameter during induction of cardiac arrest was followed by an abrupt increase at the onset of cardiac arrest. Onset of cardiac arrest also increased RV diameter in both the hyperkalemia and VF group (P<0.01 for all) (Figure). At third rhythm analysis, the RV was dilated in all groups compared with baseline (P<0.05). In the hypovolemia group, RV diameter was 32mm (95%CI 29-35) and significantly larger than in the VF group at 25mm (95%CI 22-28) (P=0.008). In the hyperkalemia group, RV diameter was 29mm (95%CI:26-32) which was not different from hypovolemia and VF (P=NS).
Conclusion: The right ventricle is dilated during resuscitation from cardiac arrest caused by hypovolemia, hyperkalemia, and ventricular fibrillation. The interpretation of echocardiographic findings in the patient with spontaneous circulation should not be extrapolated to cardiac arrest. Right ventricular dilation may be a feature inherent to cardiac arrest, rather than specific to a certain cause.
Author Disclosures: R. Aagaard: None. A. Granfeldt: None. T.M. Klausen: None. H. Kirkegaard: None. M.T. Bøtker: Other; Modest; I receive lecture fees and royalties for E-learning produced for USABCD A/S. B. Løfgren: None.
- © 2016 by American Heart Association, Inc.