Joseph Michael Brewer

Introduction: Extracorporeal membrane oxygenation (ECMO) provides lifesaving support for severe respiratory and cardiac failure. Hybrid modes such as venoarteriopulmonary (VAP) may be necessary when conventional modes fail to meet complex physiological demands. Case Report: A 31-year-old woman with dermatomyositis-associated interstitial lung disease developed severe respiratory failure. She was initiated on venovenous (VV) ECMO, later complicated by right ventricular injury (RVI) requiring conversion to venopulmonary (VP) ECMO, and ultimately required hybrid VAP ECMO for progressive RVI and cardiogenic shock while awaiting heart-lung transplantation. The unique cannulation configuration provided additional cardiorespiratory support and hemodynamic stabilization, which later enabled safe transfer for transplantation. Discussion: Hybrid VAP ECMO may provide effective rescue support for patients with refractory RVI and respiratory failure despite VP ECMO, preserve a surgically naïve chest, avoid differential oxygenation, and serve as a bridge to combined heart-lung transplant. Conclusion: Hybrid VAP ECMO represents an effective salvage strategy and bridge-to-transplant in complex cardiopulmonary failure.

Background: Refractory end-stage lung failure may benefit from extracorporeal life support (ECLS) as a bridge to lung transplantation. Venovenous (VV) extracorporeal membrane oxygenation (ECMO) is indicated in patients who have failed conventional medical treatment and mechanical ventilation. The Avalon Elite Bi-Caval Dual-Lumen Catheter (Getinge) and the Crescent Jugular Dual-Lumen Catheter (MC3, Inc., Medtronic) have been used for this configuration. Venoarterial (VA) ECMO may be used in patients with acute right ventricular (RV) failure, haemodynamic instability or refractory respiratory failure. Peripheral percutaneous approaches such as dual-site single-lumen cannulation for venopulmonary (VP) ECMO or single-site dual-lumen (dl)VP ECMO using the ProtekDuo right ventricular assist device (RVAD) cannula have been considered more recently as a bridge to transplant. These configurations support the right ventricle, prevent recirculation by placing the tricuspid and pulmonary valve between drainage and return cannulas, provide direct introduction of oxygenated blood into the pulmonary artery, and decrease the incidence of acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT) in certain disease states. This promotes haemodynamic stability and allows sedation-weaning trials, extubation, mobilisation, and pre-transplant rehabilitation. The aim of this review is the evaluation of the feasibility, outcomes and reported complications associated with dual-lumen cannulas – specifically the Avalon Elite, Crescent and ProtekDuo – used for VV and VP ECMO in adult patients requiring bridge to lung transplantation. Methods: A web-based literature search in PubMed and EMBASE was undertaken following a combination of key words. The PICOS and PRISMA approach was used. Results: Nine studies were identified out of 489 articles with a total of 251 patients placed on VV or VP ECMO as a bridge to lung transplantation. The age range was 23–68 years. The duration of ECMO support ranged from 42 h to 200 days. About 60% of patients were awake and underwent mobilisation. Survival to lung transplantation ranged from 25% to 100%. All relevant data were reviewed and integrated in the discussion. Conclusions: Single-site dual-lumen cannulation has an established role in VV ECMO bridging strategies and an emerging role in VP ECMO for patients with RV injury. Broader adoption of VP ECMO as a bridging strategy will require rigorous reporting and inclusion into multicentre registries to generate high-level evidence.

Paradoxical coronary embolism (PCE) is an uncommon cause of acute myocardial infarction (AMI), typically occurring when venous thromboemboli cross a right-to-left shunt in the setting of elevated right-sided pressures. We report a case of mixed obstructive and cardiogenic shock caused by simultaneous pulmonary embolism (PE) and PCE. A previously healthy 43-year-old woman developed profound hypoxemia and inferior ST-segment elevation 3 days after knee surgery. Coronary angiography revealed distal right coronary artery occlusion, successfully treated with aspiration thrombectomy and percutaneous coronary intervention. Persistent hypoxemia, right ventricular injury, and hemodynamic collapse prompted initiation of venoarterial extracorporeal membrane oxygenation (VA ECMO). Subsequent imaging identified extensive bilateral PE and a patent foramen ovale with significant right-to-left shunting. Catheter-based pulmonary embolectomy improved cardiopulmonary function, followed by percutaneous PFO closure. She recovered fully and was discharged home neurologically intact. This case highlights the importance of early recognition, appropriate ECMO configuration, and comprehensive management of PCE with concurrent PE.

Left ventricular assist device (LVAD)-supported patients experiencing electrical storm (ES) and cardiac arrest present unique management challenges. Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) is commonly used for extracorporeal cardiopulmonary resuscitation (ECPR), but its application in LVAD-supported patients presents hemodynamic complexities. Alternative ECMO modes, including venopulmonary (VP) and hybrid venoarteriopulmonary (VAP) ECMO, may provide tailored circulatory and respiratory support in select cases. This case report describes a patient with a newly implanted LVAD who developed ES, refractory right ventricular failure, and cardiac arrest. The patient underwent staged ECMO support, transitioning from VA ECMO for ECPR to hybrid VAP ECMO and ultimately to VP ECMO, based on evolving hemodynamic needs.

Post cardiac surgery shock (PCS) is a life-threatening condition that may require the use of mechanical circulatory support. Venoarterial (VA) extracorporeal membrane oxygenation (ECMO) is increasingly used to treat refractory PCS. We conducted a single-center, retrospective observational cohort study of adult PCS patients treated with VA-ECMO by an intensivist-led ECMO service from 2014 to 2023. Patients requiring extracorporeal cardiopulmonary resuscitation or venovenous (VV) ECMO were excluded. Baseline characteristics, ECMO support details, and outcomes were analyzed. The primary outcome was survival to hospital discharge. Multivariate regression was used to identify independent predictors of mortality. A total of 161 patients were included. The median age was 63 years and 68.3% were male. Extracorporeal membrane oxygenation was initiated peripherally in 90% of cases, with a median duration of support of 7 days. Extracorporeal membrane oxygenation weaning was achieved in 60.9% and survival to hospital discharge was 50.9%. The most common complications included renal replacement therapy (46%), left ventricular unloading (40.4%), pericardial tamponade requiring surgical intervention (34%), and neurological events (14.9%). Survival rates in this cohort were higher than those reported in previous multicenter studies, despite frequent complications. Age and total length of stay (LOS) were independent predictors of mortality, highlighting the need for optimized post-ECMO care strategies. Export

Background: Refractory end-stage pulmonary failure may benefit from extracorporeal life support (ECLS) as a bridge to lung transplantation. Veno-venous (VV) extracorporeal membrane oxygenation (ECMO) has been recommended for patients who have failed conventional medical therapy and mechanical ventilation. Veno-arterial (VA) ECMO may be used in patients with acute right ventricular (RV) failure, haemodynamic instability, or refractory respiratory failure. Peripheral percutaneous approaches, either dual-site single-lumen cannulation for veno-pulmonary (VP) ECMO or single-site dual-lumen (dl)VP ECMO, using the ProtekDuo right ventricular assist device (RVAD) cannula, has made this configuration a desirable option as a bridge to transplantation. These configurations support the right ventricle, prevent recirculation by placing the tricuspid and pulmonary valve between the drainage and return cannulas, provide the direct introduction of oxygenated blood into the pulmonary artery, and have been shown to decrease the incidence of acute kidney injury (AKI), requiring continuous renal replacement therapy (CRRT) in certain disease states. This promotes haemodynamic stability, potential sedation-weaning trials, extubation, mobilisation, and pre-transplant rehabilitation. Methods: A web-based literature search in PubMed and EMBASE was undertaken based on a combination of keywords. The PICOS and PRISMA approaches were used. Results: Four case series were identified out of 323 articles, with a total of 34 patients placed on VP ECMO as a bridge to lung transplantation. All relevant data are reviewed and integrated into the Discussion. Conclusions: Despite the limited available evidence, the use of ProtekDuo has become very promising for the management of end-stage lung disease as a bridge to lung transplantation.

Right ventricular failure (RVF) is a clinical challenge associated with various underlying acute and chronic medical conditions, necessitating diverse management strategies including mechanical circulatory support (MCS). The ProtekDuo cannula represents an important advancement in medical devices for MCS in the setting of RVF. When combined with an extracorporeal blood pump, the dual-lumen design allows for direct bypass of the RV using simultaneous drainage and return of blood using percutaneous, single-site access. Studies have reported favorable outcomes with the ProtekDuo cannula and low device-related complications, but comparative studies with other MCS devices are limited. Still, the ProtekDuo cannula has numerous advantages; however, it is not without challenges, and opportunities for further research exist. The ProtekDuo cannula holds significant potential for future advancements in the field of MCS, offering promising solutions for RVF management.