Protocol for venoarterial ExtraCorporeal Membrane Oxygenation to reduce morbidity and mortality following bilateral lung TransPlantation: the ECMOToP randomised controlled trial

Abstract

Introduction: Lung transplantation (LTx) aims at improving survival and quality of life for patients with end-stage lung diseases. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is used as intraoperative support for LTx, despite no precise guidelines for its initiation. We aim to evaluate two strategies of VA-ECMO initiation in the perioperative period in patients with obstructive or restrictive lung disease requiring bilateral LTx. In the control 'on-demand' arm, high haemodynamic and respiratory needs will dictate VA-ECMO initiation; in the experimental 'systematic' arm, VA-ECMO will be pre-emptively initiated. We hypothesise a 'systematic' strategy will increase the number of ventilatory-free days at day 28.

Methods and analysis: We designed a multicentre randomised controlled trial in parallel groups. Adult patients with obstructive or restrictive lung disease requiring bilateral LTx, without a formal indication for pre-emptive VA-ECMO before LTx, will be included. Patients with preoperative pulmonary hypertension with haemodynamic collapse, ECMO as a bridge to transplantation, severe hypoxaemia or hypercarbia will be secondarily excluded. In the systematic group, VA-ECMO will be systematically implanted before the first pulmonary artery cross-clamp. In the on-demand group, VA-ECMO will be implanted intraoperatively if haemodynamic or respiratory indices meet preplanned criteria. Non-inclusion, secondary exclusion and VA-ECMO initiation criteria were validated by a Delphi process among investigators. Postoperative weaning of ECMO and mechanical ventilation will be managed according to best practice guidelines. The number of ventilator-free days at 28 days (primary endpoint) will be compared between the two groups in the intention-to-treat population. Secondary endpoints encompass organ failure occurrence, day 28, day 90 and year 1 vital status, and adverse events.

Ethics and dissemination: The sponsor is the Assistance Publique-Hôpitaux de Paris. The ECMOToP protocol version 2.1 was approved by Comité de Protection des Personnes Ile de France VIII. Results will be published in international peer-reviewed medical journals.

Trial registration number: NCT05664204.

Keywords: Adult anaesthesia; Randomized Controlled Trial; Thoracic surgery; Transplant surgery.

Figure 1

Study protocol and randomisation arms. The screening visit will take place during the surgeons’ or pulmonologists’ visit before registration on the bilateral lung transplantation (LT) wait list. If all inclusion criteria and exclusion criteria are met, the patient will be asked to participate. If the patient agrees, informed consent will be collected. At operating room (OR) admission for the LT, the secondary exclusion criteria will be checked before randomisation according to the echocardiographic evaluation and arterial blood gas findings, after anaesthetic induction and before the beginning of surgery. If no secondary exclusion criteria is met, the investigator in charge (surgeon or anaesthesiologist) will randomise the patient to one of the treatment groups before beginning the LT procedure. For patients randomised to the experimental group (‘systematic’ ECMO), VA-ECMO will be implanted systematically before pulmonary artery cross-clamp; for patients randomised to the control group (‘on-demand’ ECMO), VA-ECMO will be implanted intraoperatively, in an unplanned manner if the haemodynamic and respiratory indices meet preplanned criteria at different time points. ECMO, extracorporeal membrane oxygenation; FEV₁, forced expiratory volume in 1 s; ICU, intensive care unit; VA, venoarterial; VV, veno-venous.