Abstract 118: Hypothermic Total Liquid Ventilation Offers Neuroprotection After Non-Shockable Cardiac Arrest
Introduction: Total liquid ventilation (TLV) with temperature-controlled perfluorocarbons can induce a potent benefit through ultrafast cooling in animal models of shockable cardiac arrest.
Hypothesis: We assessed whether TLV can also induce neuroprotection after severe non shockable cardiac arrest in rabbits.
Methods: Anesthetised rabbits were submitted to 13 min of asphyxial cardiac arrest. After cardiopulmonary resuscitation, animals were randomized to undergo normothermic life support (Control group) or hypothermia induced by i.v. cold saline (30 ml/kg; SAL group) or by 30 min of TLV with a liquid ventilator designed for pediatric use (“Inolivent-5”; TLV group). In the latter groups, hypothermia was maintained externally during 4 h at 32°C. Animals were rewarmed and weaned from mechanical ventilation after 8 h of life support. Neurological dysfunction and survival were assessed during the next 3 days.
Results: After cardiac arrest, ten rabbits were successfully resuscitated and included in each group. Target esophageal and tympanic temperatures of 32°C were reached within 5 min in the TLV group. In comparison, 90 min were required to achieve similar temperatures in the SAL group. Importantly, TLV procedure did not impair respiratory parameters such as pulmonary compliance (0.70±0.06, 0.60±0.02 and 0.59±0.03 ml/cmH2O/kg at t=5 h in Control, SAL and TLV groups, respectively). Blood gases were also similar between groups throughout mechanical ventilation (PaO2=147±9, 148±20 and 171±10 mmHg at t=6 h in Control, SAL and TLV groups, respectively; all Fi02=30%). After weaning and awakening, the neurological status was improved in TLV group as compared to the two other groups (Figure, left panel). This led to a significant improvement in survival (Figure, right panel).
Conclusion: Ultra-fast cooling by TLV improves neurologic outcome and survival after asphyxial and non shockable cardiac arrest in rabbits.
*, p<0.05 vs Control and SAL.
- © 2013 by American Heart Association, Inc.