J Pediatr Intensive Care 2019; 08(03): 193-194
DOI: 10.1055/s-0039-1692969
Letter to the Editor
Georg Thieme Verlag KG Stuttgart · New York

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

Carsten Doell
1   Department of Intensive Care Medicine and Neonatology, University Children's Hospital of Zurich, Zurich, Switzerland
2   Children's Research Center, University Children's Hospital of Zurich, University of Zurich, Zurich, Switzerland
,
3   Pediatric Intensive Care Unit, Department of Pediatrics, Geneva University Hospital, Geneva, Switzerland
,
3   Pediatric Intensive Care Unit, Department of Pediatrics, Geneva University Hospital, Geneva, Switzerland
,
Marie-Hélène Perez
4   Pediatric Intensive Care Unit, Lausanne University Hospital, Lausanne, Switzerland
,
3   Pediatric Intensive Care Unit, Department of Pediatrics, Geneva University Hospital, Geneva, Switzerland
5   Division of Pediatric Critical Care, Children's Hospital of Richmond at VCU, Richmond, VA, United States
,
Vincenzo Cannizzaro
1   Department of Intensive Care Medicine and Neonatology, University Children's Hospital of Zurich, Zurich, Switzerland
2   Children's Research Center, University Children's Hospital of Zurich, University of Zurich, Zurich, Switzerland
› Author Affiliations
Further Information

Publication History

13 March 2019

21 May 2019

Publication Date:
09 July 2019 (online)

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

We are thankful to Mattke and Venugopal for their letter and observations on our article and would like to comment on the raised concerns. We are also grateful to the Editor for the opportunity to clarify some of our results and interpretations.[1]

Prior to the initiation of extracorporeal life support (ECLS), in any given cardiopulmonary resuscitation (CPR) scenario without return of spontaneous circulation (ROSC), there is little information about eligibility criteria for starting extracorporeal cardiopulmonary resuscitation (ECPR) with a favorable outcome. Joffe et al reviewed factors predicting mortality in 762 pediatric patients with ECPR in published studies between 2000 and 2011.[2] The only pre-ECLS variable associated with mortality was noncardiac disease leading to cardiac arrest. All other variables were only available after ECLS initiation (acute kidney failure, neurological complications, and very low pH). Thiagarajan et al retrospectively analyzed 695 pediatric ECPR cases from the extracorporeal life support organization (ELSO) registry during 1992 to 2005.[3] The only pre-ECLS factor associated with increased mortality was a low-arterial blood pH. Thus, we retrospectively collected data from 55 patients undergoing ECPR for various etiologies in three different pediatric intensive care centers in Switzerland. Primary outcome (mortality) and secondary outcomes (any morbidity) were analyzed. This dataset served to calculate a risk assessment score to enable clinicians to have stronger evidence, allowing to identify appropriate ECPR candidates. CPR duration longer than 60 minutes, lactate greater than 14 mmol/L, and a pH less than 6.84 were associated with a high-risk of mortality despite ECLS initiation, with a positive predictive value of 94% regarding mortality. A just recently published study, by Bembea et al,[4] found that noncardiac diagnosis, preexisting renal insufficiency, and longer time from onset of cardiopulmonary resuscitation event to ECMO initiation where associated with increased odds of death in a cohort of 593 children undergoing ECPR following in-hospital cardiac arrest (IHCA).

First, we agree with Mattke and Venugopal that we did not distinguish between out-of-hospital cardiac arrest (OHCA) and IHCA. As there were only three (5%) OHCA in our data set, this was not statistically significant and, therefore, was not entered in the model.

Second, our data do not suggest that cut-offs were used “as a criterion for palliation.” This was neither the aim of our study nor possible given the retrospective study design. We do not have any set threshold to withdraw therapy. Any individual course is carefully evaluated and clear aims for ongoing therapy are discussed with the parents and the multidisciplinary team. Nevertheless, if irreversible severe neurological insult and progressive multiorgan failure is seen, the team weighs potential harms and benefits to prevent futile therapy. However, we agree that scores, particularly developed on the basis of retrospective data with relatively small numbers, reflect local practice and must be interpreted with caution.

Third, this study did not aim at comparing different technologies, ECLS protocols, or strategies and cointerventions during ECLS runs, nor was it meant to evaluate the results of our non-ECPR ECLS programs.

Forth, our non-ECPR results are in par with the results published by the ELSO registry. Local circumstances and structural factors most likely explain the poor outcome in our ECPR cohort. One has to consider local policies, 24/7 availability of non-ICU (intensive care unit) personnel and devices (e.g., preprimed circuits), patient selection, strict adherence to ECPR definitions, and arbitrary definitions of “favorable” neurological outcomes.

In conclusion, we are grateful for this opportunity to further discuss our results. We do acknowledge limitations, mostly our sample size, and we would like to state the importance of not overinterpreting our results. We hope that this study will help improve the care of patients, adapting the results to local strategies and values. We believe that we all have the patient's best interest in mind.

 
  • References

  • 1 De Mul A. , et al. Prognostic evaluation of mortality after pediatric resuscitation assisted by extracorporeal life support. J Pediatr Intensive Care 2019; 08 (02) 57-63
  • 2 Joffe AR, Lequier L, Robertson CMT. Pediatric outcomes after extracorporeal membrane oxygenation for cardiac disease and for cardiac arrest: a review. ASAIO J 2012; 58 (04) 297-310
  • 3 Thiagarajan RR, Laussen PC, Rycus PT, Bartlett RH, Bratton SL. Extracorporeal membrane oxygenation to aid cardiopulmonary resuscitation in infants and children. Circulation 2007; 116 (15) 1693-1700
  • 4 Bembea MM, Ng DK, Rizkalla N. , et al; American Heart Association's Get With The Guidelines – Resuscitation Investigators. Outcomes after extracorporeal cardiopulmonary resuscitation of pediatric in-hospital cardiac arrest: a report from the get with the guidelines-resuscitation and the extracorporeal life support organization registries. Crit Care Med 2019; 47 (04) e278-e285