Prognostic Evaluation of Mortality after Pediatric Resuscitation Assisted by Extracorporeal Life Support

Reply to: Prognostic Evaluation of Mortality after Pediatric Resuscitation Assisted by Extracorporeal Life Support

De Mul et al described the outcomes of extracorporeal cardiopulmonary resuscitation (ECPR) in three pediatric intensive care centers in Switzerland, with a mortality of 75%, and intact neurological survival of 16% overall.[1] We commend the authors on the publication of these data, particularly given that high-mortality studies underlie publication bias. De Mul's data contrast with ECPR outcomes both from the extracorporeal life support organization (ELSO), as well as recent large and medium sized reports, where mortality usually ranges below 50%.[2] [3] [4] [5]

De Mul et al do not distinguish between out-of-hospital and in-hospital cardiac arrest (OOHCA and IHCA, respectively). The distinction between the two is paramount, as outcomes after either event differ hugely, and any outcome prediction score based on a mix of the two types of events will overestimate survival for OOHCA, and underestimate the survival of IHCA. As such, we would caution to use a score based on both types of events for clinical practice.

The median survival on extracorporeal membrane oxygenation (ECMO) after ECPR in De Mul's report was 4.3 days, and in 20 of 30 patients who died on extracorporeal life support (ECLS), “multiorgan failure” or “ischemic encephalopathy” was the cause of death. Both causes for death are not clearly defined, and we suggest commenting specifically on how many patients were palliated given ECLS can be the treatment for multiorgan failure, particularly in septic patients on ECLS.[6] De Mul's data suggest that a cutoff of 5 days (after which patient were palliated) was used as a criterion for palliation, though this is not declared in the report. If patients were indeed palliated, then the score that predicts survival after ECPR would reflect local practices of and views toward palliation more than the effectiveness of ECPR. In our, currently unpublished, data of 64 ECPR cases we could show that in 20 patients where ECLS support lasted longer than 5 days survival was still 45% suggesting that palliation at 5 days after ECPR may be premature.

ECLS flow rates correlate with “reversal of shock,” and “time to lactate clearance” and may be associated with outcomes after ECPR.[5] [7] However, the ECLS strategy after ECPR is not mentioned in the report but may be a clue to why the outcomes were poorer when compared with other reports, or the ELSO data.

We suggest that the authors state the outcomes in their non-ECPR ECLS patients. If the outcomes in this population were on par with the ELSO reported ones, then factors in the initiation of ECPR may contribute to the high mortality. Should the overall outcomes for ECLS patient, however, be lower than ELSO reported ones then the ECLS management strategy would become a focus of interest for the reader. After all, De Mul's report should remind us all that good ECPR outcomes are hard to achieve, and we should seek to identify the (modifiable) factors that lead to good results in this patient group.

• References

• 1 De Mul A, Nguyen DA, Doell C, Perez MH, Cannizzaro V, Karam O. Prognostic evaluation of mortality after pediatric resuscitation assisted by extracorporeal life support. J Pediatr Intensive Care 2019; 08 (02) 057-063
• 2 Alsoufi B, Awan A, Manlhiot C. , et al. Results of rapid-response extracorporeal cardiopulmonary resuscitation in children with refractory cardiac arrest following cardiac surgery. Eur J Cardiothorac Surg 2014; 45 (02) 268-275
• 3 Chan T, Thiagarajan RR, Frank D, Bratton SL. Survival after extracorporeal cardiopulmonary resuscitation in infants and children with heart disease. J Thorac Cardiovasc Surg 2008; 136 (04) 984-992
• 4 Prodhan P, Fiser RT, Dyamenahalli U. , et al. Outcomes after extracorporeal cardiopulmonary resuscitation (ECPR) following refractory pediatric cardiac arrest in the intensive care unit. Resuscitation 2009; 80 (10) 1124-1129
• 5 Mattke AC, Stocker CF, Schibler A, Alphonso N, Johnson K, Karl TR. A newly established extracorporeal life support assisted cardiopulmonary resuscitation (ECPR) program can achieve intact neurological outcome in 60% of children. Intensive Care Med 2015; 41 (12) 2227-2228
• 6 MacLaren G, Butt W, Best D, Donath S. Central extracorporeal membrane oxygenation for refractory pediatric septic shock. Pediatr Crit Care Med 2011; 12 (02) 133-136
• 7 Sivarajan VB, Best D, Brizard CP, Shekerdemian LS, d'Udekem Y, Butt W. Duration of resuscitation prior to rescue extracorporeal membrane oxygenation impacts outcome in children with heart disease. Intensive Care Med 2011; 37 (05) 853-860