Objective

Although extracorporeal life support (ECLS) has been increasingly adopted as rescue therapy for cardiac and pulmonary failure, it remains limited to specialized centers. The present study reports our institutional experience with mobile ECLS across broad indications, including postcardiotomy syndrome, cardiogenic shock, and COVID-19 acute respiratory failure.

Methods

We performed a retrospective review of all patients transported to our institution through our mobile ECLS program from January 1, 2018, to January 15, 2021.

Results

Of 110 patients transported to our institution on ECLS, 65.5% required venovenous, 30.9% peripheral venoarterial, and 3.6% central venoarterial support. The most common indications for mobile ECLS were acute respiratory failure (46.4%), COVID-19-associated respiratory failure (19.1%), cardiogenic shock (18.2%) and postcardiotomy syndrome (11.8%). The median pre-ECLS Pao₂:Fio₂ for venovenous-ECLS was 64 mm Hg (interquartile range [IQR], 53-75 mm Hg) and 95.8 mm Hg (IQR, 55-227 mm Hg) for venoarterial-ECLS, whereas median pH and base deficit were 7.25 (IQR, 7.16-7.33) and 7 mmol/L (IQR, 4-11 mmol/L) for those requiring venoarterial-ECLS. Patients were transported using a ground ambulance from 50 institutions with a median distance of 27.5 miles (IQR, 18.7-48.0 miles). Extracorporeal circulation was established within a median of 45 minutes (IQR, 30-55 minutes) after team arrival. Survival to discharge was 67.3% for those requiring venovenous-ECLS for non-COVID-19 respiratory failure, 52.4% for those with COVID-19%, and 54.1% for those requiring venoarterial-ECLS.

Conclusions

Patients can be safely and expeditiously placed on ECLS across broad indications, utilizing ground transportation in an urban setting. Clinical outcomes are promising and comparable to institutional non-transfers and those reported by Extracorporeal Life Support Organization.

Previous experience has shown that transporting patients on extracorporeal membrane oxygenation (ECMO) is a safe and effective mode of transferring critically ill patients requiring maximum mechanical ventilator support to a quaternary care center. The coronavirus disease 2019 (COVID-19) pandemic posed new challenges. This is a multicenter, retrospective study of 113 patients with confirmed severe acute respiratory syndrome coronavirus 2, cannulated at an outside hospital and transported on ECMO to an ECMO center. This was performed by a multidisciplinary mobile ECMO team consisting of physicians for cannulation, critical care nurses, and an ECMO specialist or perfusionist, along with a driver or pilot. Teams practised strict airborne contact precautions with eyewear while caring for the patient and were in standard Personal Protective Equipment. The primary mode of transportation was ground. Ten patients were transported by air. The average distance traveled was 40 miles (SD ±56). The average duration of transport was 133 minutes (SD ±92). When stratified by mode of transport, the average distance traveled for ground transports was 36 miles (SD ±52) and duration was 136 minutes (SD ±93). For air, the average distance traveled was 66 miles (SD ±82) and duration was 104 minutes (SD ±70). There were no instances of transport-related adverse events including pump failures, cannulation complications at outside hospital, or accidental decannulations or dislodgements in transit. There were no instances of the transport team members contracting COVID-19 infection within 21 days after transport. By adhering to best practices and ACE precautions, patients with COVID-19 can be safely cannulated at an outside hospital and transported to a quaternary care center without increased risk to the transport team.

Purpose of the review

This is a comprehensive update on failing Fontan physiology and the role of heart and combined heart and liver transplantation in the current era.

Recent findings

Single ventricle physiology encompasses a series of rare congenital cardiac abnormalities that are characterized by absence of or hypoplasia of one ventricle. This effectively results in a single ventricular pumping chamber. These abnormalities are rarely compatible with long-term survival if left without surgical palliation in the first few years of life. Surgical treatment of single ventricle physiology has evolved over the past 60 years and is characterized by numerous creative innovations. These include the development of arteriopulmonary shunts, the evolution of partial cavopulmonary connections, and the eventual development of the "Fontan" operation. Regardless of the type of Fontan modification, the long-term consequences of the Fontan operation are predominantly related to chronic central venous hypertension and the multi-organ consequences thereof. Atrial arrhythmias can further compromise this circulation.Patients with single ventricle physiology represent a special sub-segment of congenital cardiac transplants and are arguably the most challenging patients considered for transplantation.

Summary

This review describes in detail the challenges and opportunities of heart and liver transplantation in Fontan patients, as viewed and managed by the experienced team at the Ahmanson/UCLA Adult Congenital Heart Center.

The role of veno-venous extracorporeal membrane oxygenation therapy (V-V ECMO) in severe COVID-19 acute respiratory distress syndrome (ARDS) is still under debate and conclusive data from large cohorts are scarce. Furthermore, criteria for the selection of patients that benefit most from this highly invasive and resource-demanding therapy are yet to be defined. In this study, we assess survival in an international multicenter cohort of COVID-19 patients treated with V-V ECMO and evaluate the performance of several clinical scores to predict 30-day survival. This is an investigator-initiated retrospective non-interventional international multicenter registry study (NCT04405973, first registered 28 May 2020). In 127 patients treated with V-V ECMO at 15 centers in Germany, Switzerland, Italy, Belgium, and the United States, we calculated the Sequential Organ Failure Assessment (SOFA) Score, Simplified Acute Physiology Score II (SAPS II), Acute Physiology And Chronic Health Evaluation II (APACHE II) Score, Respiratory Extracorporeal Membrane Oxygenation Survival Prediction (RESP) Score, Predicting Death for Severe ARDS on V‑V ECMO (PRESERVE) Score, and 30-day survival. In our study cohort which enrolled 127 patients, overall 30-day survival was 54%. Median SOFA, SAPS II, APACHE II, RESP, and PRESERVE were 9, 36, 17, 1, and 4, respectively. The prognostic accuracy for all these scores (area under the receiver operating characteristic-AUROC) ranged between 0.548 and 0.605. The use of scores for the prediction of mortality cannot be recommended for treatment decisions in severe COVID-19 ARDS undergoing V-V ECMO; nevertheless, scoring results below or above a specific cut-off value may be considered as an additional tool in the evaluation of prognosis. Survival rates in this cohort of COVID-19 patients treated with V‑V ECMO were slightly lower than those reported in non-COVID-19 ARDS patients treated with V-V ECMO.