Therapeutic hypothermia after cardiac arrest: outcome predictors

Abstract

Objective The determination of coma patient prognosis after cardiac arrest has clinical, ethical and social implications. Neurological examination, imaging and biochemical markers are helpful tools accepted as reliable in predicting recovery. With the advent of therapeutic hypothermia, these data need to be reconfirmed. In this study, we attempted to determine the validity of different markers, which can be used in the detection of patients with poor prognosis under hypothermia.Methods Data from adult patients admitted to our intensive care unit for a hypothermia protocol after cardiac arrest were recorded prospectively to generate a descriptive and analytical study analyzing the relationship between clinical, neurophysiological, imaging and biochemical parameters with 6-month outcomes defined according to the Cerebral Performance Categories scale (good 1-2, poor 3-5). Neuron-specific enolase was collected at 72 hours. Imaging and neurophysiologic exams were carried out in the 24 hours after the rewarming period.Results Sixty-seven patients were included in the study, of which 12 had good neurological outcomes. Ventricular fibrillation and electroencephalographic theta activity were associated with increased likelihood of survival and improved neurological outcomes. Patients who had more rapid cooling (mean time of 163 versus 312 minutes), hypoxic-ischemic brain injury on magnetic resonance imaging or neuron-specific enolase > 58ng/mL had poor neurological outcomes (p < 0.05).Conclusion Hypoxic-ischemic brain injury on magnetic resonance imaging and neuron-specific enolase were strong predictors of poor neurological outcomes. Although there is the belief that early achievement of target temperature improves neurological prognoses, in our study, there were increased mortality and worse neurological outcomes with earlier target-temperature achievement.

Mild therapeutic hypothermia after out-of-hospital cardiac arrest: What does really matter?

“…Lee et al [15] also reported lower initial GCS scores along with nonshockable rhythm, longer time in cardiac arrest and a higher Sequential Organ Failure Assessment (SOFA) score were independent risk factors for mortality, while no association was found between other time variables (pre-induction and induction) and odds for survival. In contrast to previous results, Leão et al [27] showed a correlation between higher mortality at 6 months after cardiac arrest and shorter time to TT.…”

“…A study evaluating heat generation in patients treated with MTH after cardiac arrest revealed an association between greater heat production and better baseline health status, reduced ischemic injury and improved neurologic outcome [26]. A study published by Leão et al [27] showed that, apart from shorter induction time, patients with unfavorable neurologic outcome had a higher incidence of hypoxic-ischemic brain injury on magnetic resonance imagining and a higher concentration of neuron specific enolase. The present results are consistent with these studies [14,15,19,26,27] and might indirectly support the hypothesis that shorter induction time in patients with unfavorable neurological outcome is related to more severe brain injury, since the initial neurologic condition reflected by GCS on admission was a strong outcome predictor.…”

“…A study published by Leão et al [27] showed that, apart from shorter induction time, patients with unfavorable neurologic outcome had a higher incidence of hypoxic-ischemic brain injury on magnetic resonance imagining and a higher concentration of neuron specific enolase. The present results are consistent with these studies [14,15,19,26,27] and might indirectly support the hypothesis that shorter induction time in patients with unfavorable neurological outcome is related to more severe brain injury, since the initial neurologic condition reflected by GCS on admission was a strong outcome predictor. Furthermore, an association between longer MTH induction time and higher GCS score was found in univariate analysis, however results were not confirmed in the multivariate model.…”

Factors Affecting Prognosis in Hypoxic Encephalopathy Patients Followed-up in Intensive Care Unit

“…Beyin MRG'de hipoksik etkilenme bulguları görülen hastalarda prognoz, etkilenme olmayanlara göre 19 kat daha kötüdür (29). Hipoksinin yeri ve prognozla ilgili veriler çelişkilidir.…”

Critical Care Management Focused on Optimizing Brain Function After Cardiac Arrest

“…115 Other studies have shown that the faster the target temperature is reached, the higher the mortality and the worse the neurologic outcome. 116, 117 It is hypothesized that patients with more severe or irreversible neurologic damage are less reactive to low temperatures, so there is less shivering 117 and less requirement for NMB. 118 The relationship between shivering and outcome has yet to be fully elucidated.…”