Re: ECMO in trauma
We thank Dr. Swol et al. for their interest in our work and for their letter that has contributed to clarify, with a broad literature review, how evolving and controversial the knowledge on use of extracorporeal membrane oxygenation (ECMO) in trauma patients is.
As you correctly pointed out, the main focus of our systematic review was to concentrate on anticoagulation management in polytrauma patients receiving veno-venous (vv)-ECMO. Therefore, as described in our work, we excluded publications in which other extracorporeal life support (ECLS) modalities were used and data on anticoagulation management and related outcomes were not available.1 We used such restrictive inclusion criteria in the attempt to have a sample as homogeneous and informative as possible.
We absolutely agree that the inclusion of case reports and case series in our review and the exclusion of big retrospective studies may underestimate mortality rate in this population, but the estimation of the mortality rate was not the aim of our work. Furthermore, considering the sample size, we are not able to make any inference regarding outcomes in terms of mortality. Several well-known and recently published retrospective cohort studies have already addressed this issue, and as you mentioned, there is a wide variability in mortality outcomes in trauma patients treated with ECLS techniques.2–5 This variability might be related to multiple factors: the retrospective analysis of heterogeneous samples and an improving trend in mortality in recent years, related to a better understanding of indications and improvement in technology, can be among the most important.
An increasing number of trauma patients has been treated with ECLS techniques in recent years, and we absolutely agree with you that the addition of a specific category for “trauma” in the extracorporeal life support organization (ELSO) registry is imperative and should be supported. This could increase our knowledge both in terms of mortality and morbidity outcomes and improve the management of this important category of patients.