The effect of therapeutic hypothermia after cardiopulmonary resuscitation on ICAM-1 and NSE levels in sudden cardiac arrest rabbits

Abstract

Purpose: To assess the effects of hypothermia and normothermia treatments for sudden cardiac arrest (SCA) on brain injury recovery in rabbit models. Methods: Cardiopulmonary resuscitation (CPR) was implemented on apnea-induced SCA rabbit models. Fifty survived rabbits were then randomly received hypothermia (n = 25, 32–34°C) or normothermia treatment (n = 25, 39–39.5°C) for 12 hours. The expected body temperatures were achieved within the first two hours, maintained for ten hours and then rewarmed. The physiological parameters, neurologic function, and the levels of adhesion molecule ICAM-1 and neuron-specific enolase (NSE) were monitored. Results: Hypothermia-treated rabbits had lower heart rate when achieving hypothermia (p < 0.0001) and higher SjvO₂ after hypothermia maintenance (p = 0.038). The hypothermia group achieved better brain recovery performance according to the neurological deficit grading scale. ICAM-1 and NSE levels in both serum and CSF of the hypothermia group were lower than the normothemia group (all p < 0.0001) during hypothermia maintenance. Conclusion: Hypothermia treatment after CPR provides better outcome than normothermia treatment in SCA rabbits. Hypothermia can reduce the ICAM-1 and NSE levels in both serum and cerebrospinal fluid (CSF). This study supports the clinical implementation of hypothermia treatment for SCA and reveals that ICAM-1 and NSE are involved in the recovery of brain function after resuscitation.

KEYWORDS:

• hypothermia
• sudden cardiac arrest
• ICAM-1
• NSE