SGEM #404: Sitting on the Dock of the Bay-esian Interpretation of Therapeutic Hypothermia for Pediatric Cardiac Arrest

Date: May 10, 2023 Reference: Harhay MO, et al. A bayesian interpretation of a pediatric cardiac arrest trial (THAPCA-OH). NEJM Evidence. 2023. Guest Skeptic: Dr. Kat Priddis is a paediatric emergency medicine consultant and trauma director at Watford General Hospital. She is part of the Don’t Forget the Bubbles team and faculty at Queen Mary University in London where she teaches part of the Paediatric Emergency Medicine MSc. Dr. Kat Priddis Case: You are working at the community emergency department (ED) when you receive a call from the local Emergency Medicine Service (EMS) team that they are bringing a 2-year-old boy who had a cardiac arrest at home. He had been having some upper respiratory symptoms in the previous days. Parents found him in bed that morning blue and unresponsive. They started cardiopulmonary resuscitation (CPR) until EMS arrived.  Upon arrival at the ED, your team promptly begins high quality CPR and manages to obtain return of spontaneous circulation. As you are mentally running through your checklist for post-arrest care and preparing to transfer the patient, a team member tells you that there are potentially two hospitals in the area who may be able to accept the patient. One of the hospitals has a pediatric intensive care unit (PICU) that has the capability to perform therapeutic hypothermia but it’s further away. Which hospital should you transfer the patient to? Background: Therapeutic hypothermia in cardiac arrest has been covered on the SGEM multiple times, all the way back to SGEM #21 and SGEM #54 and most recently in SGEM #391. Ken and Justin Morgenstern of First10EM provided a very nice summary of the history of therapeutic hypothermia that you can check out, so we won’t belabor the point. Other therapeutic hypothermia trials included Target Temperature Management or TTM trial (SGEM #82), HYPERION (SGEM #275), TTM2 (SGEM #336). However, we have not covered the Therapeutic Hypothermia after Out-of-Hospital Cardiac Arrest (OHCA) in Children or THAPCA-OH published in the New England Journal of Medicine in 2015. We’re adding on a second paper looking at the Bayesian interpretation of the original study.  Clinical Question: Does therapeutic hypothermia provide any benefit in neurobehavioral outcomes and survival in out-of-hospital pediatric cardiac arrest? Original trial: Moler FW, Silverstein FS, Holubkov R, et al. Therapeutic hypothermia after out-of-hospital cardiac arrest in children. N Engl J Med. 2015. Reference: Harhay MO, et al. A bayesian interpretation of a pediatric cardiac arrest trial(THAPCA-OH). NEJM Evidence. 2023. Population: 295 pediatric patients (ages greater than two days to less than 18 years) hospitalized in PICUs at 38 children’s hospitals, who were admitted after OHCA.  Excluded: Inability to randomize within 6 hours of ROSC, Glasgow Coma Scale (GCS) motor score of 5 or 6, decision to withhold aggressive treatment by clinical team, traumatic arrest Intervention: Therapeutic hypothermia (target temperature 33°C).  Comparison: Therapeutic normothermia (target temperature 36.8°C) Outcome:  Primary Outcome: Survival with good neurobehavioral outcome at 12 months. Outcome defined by Vineland Adaptive Behavior Scales (VABS-II) of 70 or higher (this is a scale from 20 to 160 with higher scores associated with better function) Secondary Outcomes: Survival at 12 months and change in neurobehavioral function Other Outcomes: Global cognitive score, blood product use, infection, serious arrhythmias through 7 days, 28-day mortality Trial: Multinational unmasked randomized clinical trial  Authors’ Conclusions Original Paper: “In comatose children who survive out-of-hospital cardiac arrest, therapeutic hypothermia, as compared to therapeutic normothermia, did not confer a significant benefit in survival with a good functional outcome at 1 year.”