Hypothermia Therapy After Pediatric Cardiac Arrest

Abstract

Background-Hypothermia therapy improves mortality and functional outcome after cardiac arrest and birth asphyxia in adults and newborns. The effect of hypothermia therapy in infants and children with cardiac arrest is unknown. Methods and Results-A 2-year, retrospective, 5-center study was conducted, and 222 patients with cardiac arrest were identified. Seventy-nine (35.6%) of these patients met eligibility criteria for the study (age Ͼ40 weeks postconception and Ͻ18 years, cardiac arrest Ͼ3 minutes in duration, survival for Ն12 hours after return of circulation, and no birth asphyxia). Twenty-nine (36.7%) of these 79 patients received hypothermia therapy and were cooled to 33.7Ϯ1.3°C for 20.8Ϯ11.9 hours. Hypothermia therapy was associated with higher mortality (Pϭ0.009), greater duration of cardiac arrest (Pϭ0.005), more resuscitative interventions (PϽ0.001), higher postresuscitation lactate levels (PϽ0.001), and use of extracorporeal membrane oxygenation (PϽ0.001). When adjustment was made for duration of cardiac arrest, use of extracorporeal membrane oxygenation, and propensity scores by use of a logistic regression model, no statistically significant differences in mortality were found (Pϭ0.502) between patients treated with hypothermia therapy and those treated with normothermia. Also, no differences in hypothermia-related adverse events were found between groups. Conclusions-Hypothermia therapy was used in resuscitation scenarios that are associated with greater risk of poor outcome. In an adjusted analysis, the effectiveness of hypothermia therapy was neither supported nor refuted. A randomized controlled trial is needed to rigorously evaluate the benefits and harms of hypothermia therapy after pediatric cardiac arrest. (Circulation. 2009;119:1492-1500.)

Guidelines for the Determination of Brain Death in Infants and Children: An Update of the 1987 Task Force Recommendations

“…[19][20][21][22] Hypothermia has also been used following cardiac arrest to protect the brain because it reduces cerebral metabolic activity. [23][24][25][26] The clinician caring for critically ill infants and children should be aware of the potential impact of therapeutic modalities such as hypothermia on the diagnosis of brain death. Hypothermia is known to depress central nervous system function [27][28][29] and may lead to a false diagnosis of brain death.…”

Pediatric Neurocritical Care

“…Patients treated with hypothermia had longer duration of cardiac arrest, more resuscitative efforts, higher lactate, and greater use of extracorporeal membrane oxygenation. After adjusting for these variables, there was no statistically significant difference in mortality between the hypothermia and standard treatment groups [169].…”

“…The groundwork for this study has been well built. Three large, retrospective cohort studies that included patients from 15 hospitals affiliated with the Pediatric Emergency Care Applied Research Network have examined the outcome and identified risk factors associated with poor outcome for both in-hospital and out-of-hospital pediatric cardiac arrest [161][162][163][164][165][166][167][168][169][170][171]. Surveys from the United Kingdom and the United States have demonstrated both variability in the practice of cooling, and a widespread willingness and interest in a randomized controlled trial to study its use [172,173].…”

What is new in the 2015 American Heart Association guidelines, what is recycled from 2010, and what is relevant for emergency medicine in Canada

“…For children who remain in a coma after an OHCA, a TTM strategy is recommended when initiated in the ED or ICU setting. Based on the current evidence, 31,32 clinicians may target 36°C [96.8°F] to 37.5°C (99.5°F) for 5 days or may target 32°C (89.6°F) to 34°C (93.2) for 2 days followed by 3 days of normothermia. Whereas, with respect to paramedics starting TTM in the prehospital setting after pediatric cardiac arrest, there is no clear guidance on which is the correct target temperature.…”