Abstract 18181: Intravascular Coagulation During Prolonged Cardiac Arrest
Background: A potential barrier to the success of extracorporeal cardiopulmonary resuscitation (ECPR) after prolonged cardiac arrest is the “no-reflow phenomenon”, and intravascular coagulation is hypothesized to be an important contributor. In this study we characterized the coagulopathy of prolonged cardiac arrest and tested the hypothesis that early anticoagulation reduces cerebral microvascular thrombus formation.
Methods: Fifteen swine (50 kg SD±7) were subjected to electrically-induced ventricular fibrillation (VF). Animals were block randomized into three experimental groups: No CPR group (n=5) consisting of 60 minutes of untreated VF, CPR group (n=5) 10 minutes of untreated VF followed by 50 minutes of CPR, CPR with Heparin group (n=5) 10 minutes of untreated VF followed by 50 minutes of CPR with a single heparin bolus (200 U/kg) delivered 14 minutes after VF onset. Naïve swine were use as normal controls (n=4). In the CPR group, systemic coagulation was assessed by venous thromboelastography (TEG) at baseline, 30, 45, and 60 minutes. Brains were removed after 60 minutes of cardiac arrest and cerebral microvascular fibrin deposition was quantified using Martius Scarlet Blue (MSB) stain of paraffin-embedded, formalin fixed samples of the parietal cortex.
Results: Baseline characteristics were the same between groups. TEG revealed an initial hypercoagulable state (decreased R, K, TMA and increased Alpha angle) during the first 45 minutes of cardiac arrest with CPR, followed by impaired clot formation (increased R, K, TMA, and decreased Alpha angle) at 60 minutes. The density of fibrin-labeled microvasculature (vessels/mm2) in each group was not statistically different: 55.9±3.7 Naïve; 74.1±15.4 No CPR; 76.9±20.8 CPR; 77.8±12.6 CPR with Heparin (p=0.15).
Conclusion: Prolonged cardiac arrest with CPR is associated with an initial prothrombotic state resulting in a consumptive coagulopathy occurring after approximately 45 minutes. Although cerebral microvascular fibrin deposition was observed in all groups, we were unable to demonstrate a statistically significant increase after 60 minutes of cardiac arrest. Future studies are needed to explore the impact microvascular coagulation in resuscitation from prolonged cardiac arrest.
Author Disclosures: R.A. Coute: Other Research Support; Modest; Sarnoff Cardiovascular Research Foundation Fellowship. N.L. Werner: None. A. Rojas-Pena: None. S. Rakestraw: None. F. Alghanem: None. M. Tiba: None. R.H. Bartlett: None. R.W. Neumar: Research Grant; Modest; American Heart Association Grant-in-Aid (15GRNT25890002).
- © 2016 by American Heart Association, Inc.