Peri-operative extracorporeal cardiopulmonary resuscitation - a reply.

Abstract

We thank Charlesworth and Ashworth for their comments on our paper 1. We had no predefined extracorporeal cardiopulmonary resuscitation (ECPR) protocol before 2014; the decision to call the extracorporeal membrane oxygenation (ECMO) team to the operating room was made by the attending anaesthetist, the leader of intra-operative CPR team and the final decision about the institution of ECPR was made in discussion with the ECMO team leader. In January 2014, we out together a multidisciplinary ECMO team including critical care medicine, cardiology and cardiovascular surgery, and developed shared protocols and institutional guidelines for ECMO activation and management 2. The ECMO leader on-call is responsible for the decision to initiate ECMO, and the first available cardiovascular surgeon uses a pre-primed, ready-to-use ECMO circuit. We are involved in ongoing discussions with our ECMO team about the minimum criteria for ECPR, particularly around when not to initiate treatment. Generally, discussion occurs in the operating room once the ECMO team has been contacted. Extracorporeal membrane oxygenation therapy is expensive and controversial in patients with haemorrhage, but can be life-saving in some patients who would have been very unlikely to survive without ECPR. We agree that appropriate patient selection is the key to successful ECPR. We included veno-venous ECMO (VV-ECMO) in our analysis because ‘ECPR’ generally refers to the implantation of venous-arterial ECMO. In the absence of a clear and univocal definition of ECPR, we thought that CPR with the assistance of VV-ECMO for pulmonary resuscitation should be considered to be ECPR when return of spontaneous circulation (ROSC) could not be sustained due to profound respiratory failure. In the three patients with severe acute respiratory failure in our study, immediate ROSC after conventional CPR was not sustained without VV-ECMO. We found that femoral ECMO procedures could be performed without interrupting abdominal or haemostatic procedures, including compression or clamping. Any decision about ECMO was made only when the surgeon was confident about haemostasis. In some cases, the cardiovascular surgeon helped repair a vascular injury. The routine use of systemic anticoagulation could be dangerous in coagulopathic patient, necessitating point-of-care coagulation monitoring. We think the real survival rate may have been underestimated in our retrospective analysis. We did not review all cases of intra-operative CPR during the study period, and so we could not assess the survival of patients who might have benefitted from ECPR correctly initiated during their intra-operative cardiac arrest. We agree with Charlesworth and Ashworth that improving patient outcomes using ECPR requires multidisciplinary teamwork, and involves well-defined and implemented protocols.