Year in review: Highlights in ECLS Innovation and Technology,Anno 2022-2023

Abstract

Background

In the field of extracorporeal life support (ECLS), the rapid influx of novel technologies and innovative techniques presents an ongoing challenge for professionals to stay informed about these advancements. To address this issue and ensure the ECLS community remains up-to-date, we have compiled a concise overview of recent technological innovations in ECLS.

Purpose

This overview focuses primarily on academically investigated and reported advancements in the ECLS domain. It underscores the importance of transparent communication regarding technological limitations in healthcare and advocates for collaboration between medical professionals and engineers to elevate patient care.

Research Design

This manuscript presents a compilation of recent technological advancements in ECLS, with an emphasis on innovations that have been academically explored and documented. The research approach involves gathering information from scholarly sources, reports, and studies to provide a comprehensive overview.

Study Sample

The study sample comprises a diverse range of recent technological innovations in the field of extracorporeal life support (ECLS). These innovations span various aspects of ECLS technology and have been investigated and reported on within the academic literature.

Analysis

Data collection involved systematically reviewing academic literature, reports, and studies related to recent technological advancements in ECLS. The collected information was then analyzed to identify common trends, notable developments, and the impact of these innovations on patient care.

Results

The compilation highlights several significant technological innovations within the ECLS domain. Notable advancements include the development of new dual lumen cannulae, innovative devices for left ventricular (LV) unloading, lightweight ECMO transport systems, streamlined driving consoles to facilitate patient mobility, intricate systems for extracorporeal cardiopulmonary resuscitation (ECPR), standardized driving consoles for networking, and non-invasive circuit pressure monitoring. Some of these innovations have obtained regulatory approvals for distribution in the United States and/or authorization for the European market.

Conclusions

The manuscript underscores the critical role of collaboration between clinicians, researchers, and industry in driving recent technological innovations within the ECLS field. It emphasizes the necessity of open communication about technological limitations and the potential for repurposing established technologies in novel ways. However, the resourcefulness of physicians in repurposing devices requires validation through comprehensive scientific and technical investigation. Thus, fostering broader collaboration among stakeholders is recommended to ensure the rigorous evaluation and validation of new applications for established ECLS devices.

Introduction

Necessity is the mother of invention, and throughout the development of ECLS technology, numerous needs and shortcomings have been recognized and efforts have been done to meet them. Many needs arise from extended patient indications as well as from complications inherent to ECLS support. In addition to identifying these needs, it has been demonstrated that constructive dialogue between those identifying the needs and those capable of providing solutions is essential.

Before new technology reaches the clinician, the manufacturers have to navigate regulatory demands to receive a United States Food and Drug Administration (FDA) approval or the European CE mark.^1–4

A CE mark allows a device to be sold in Europe, while for exportation or sales outside Europe, obtaining FDA approval is mandatory. Additionally, in the UK, the CE marking will be replaced by a new UKCA marking after June 30, 2023. Historically, the CE mark has been the preferred route for registering novel medical technologies due to its faster, more cost-effective, and predictable processes. However, the situation has now changed, especially considering that certain ECLS circuit components, such as ECMO cannulas, are being reclassified by the European Medical Device Regulation from Class IIb (intermediate risk) to Class III (high risk). ¹ This reclassification imposes more stringent requirements, including the need for clinical evaluation of the device.^2,3

In the US, certain medical device regulations established by the FDA, specifically the 510(k) clearance process, expedite the introduction and oversight of new technologies. This is achieved by demonstrating that the new technology is substantially equivalent (SE) in terms of safety and effectiveness to one or more comparable devices that are already legally marketed or FDA cleared. It is important to note that clinical data is not required for this process. The 510(k) clearance process primarily applies to medium-risk or Class II medical devices, such as ECLS devices. However, if substantial equivalence cannot be established, an alternative pathway is available through the submission of a De Novo application to obtain FDA clearance. The De Novo pathway shares similarities with the 510(k) process but necessitates the submission of clinical data and evidence demonstrating that the device carries medium risk. ¹ Consequently, for medical devices cleared through the 510(k) process, it is crucial to prioritize post-market surveillance and device-related reporting to identify any flaws or shortcomings in the technology. ⁴

This manuscript will provide a concise overview of recently introduced ECLS-related technologies and briefly explain the reasons behind their emergence in the market. Moreover, it seeks to emphasize the crucial role that clinicians and technical specialists play in identifying and reporting shortcomings to researchers, industry representatives, and official complaint institutions.

Dual lumen cannulas

In the context of neonatal venovenous extracorporeal membrane oxygenation (VV ECMO), the use of dual lumen (DL) cannulas has posed challenges due to the unique physiology of the pediatric vascular system. To address these challenges, the development of a DL cannula in 1989, initially with a right atrial (RA) design and later a bicaval (BC) design, proved to be significant. The OriGen® RA DL cannula gained popularity among surgeons due to its ease of bedside placement and favorable outcomes. ⁵

While the Avalon® cannula also emerged as the only BC DL cannula sized for neonates, technical challenges and complications associated with its use in the neonatal population made it more commonly utilized in older children and adults. Consequently, the discontinuation of the sole remaining neonatal RA DL cannula on the market prompted changes in neonatal cannulation practices. Clinicians began opting for a venoarterial (VA) approach instead of transitioning to the BC cannula.^5–9

In late 2021, the introduction of the 13 Fr DL RA cannula (Medtronic Crescent®) provided an alternative for neonatal respiratory ECMO cannulation. Initial results have shown promising support with limited recirculation and few complications. However, further research is required to assess its overall effectiveness. The Crescent® pediatric cannula is available in sizes of 13, 15, and 19 Fr, has received FDA clearance, and is currently awaiting CE marking. ¹⁰

The adult BC Crescent® cannula (Medtronic) has gained significant attention since its introduction to the market. Clinical reports indicate that the standard insertion site of the right internal jugular vein can be expanded to include the subclavian vein and left internal jugular vein, making the cannula placement more feasible and versatile. Notably, the use of this cannula has been associated with minimal complications, such as minor repositions, bleeding, and recirculation issues. The speed of insertion and achieved flows have been reported as effective, further supporting the clinical utility of this cannula. ¹¹ One case report highlighted a rare occurrence of a broken dual lumen Crescent® cannula after 2 weeks of ECMO support. The rupture was observed on the inflow side, leading to air aspiration into the ECMO circuit. It is noteworthy that this specific cannula was inserted through the left subclavian vein, and the fracture site was identified approximately 2 cm distal to the skin insertion point. This case report emphasizes the importance of ongoing monitoring and assessment of cannula integrity during ECLS support. ¹²

A recent report explored the feasibility of using mobile X-ray imaging during the insertion of the Crescent® DLC cannula. This approach offers the advantage of avoiding patient transportation for fluoroscopy, which is particularly relevant for critically ill or infectious patients. Additionally, in awake patients, the need for transesophageal echocardiography (TOE) can be eliminated, simplifying the cannula insertion procedure. ¹³

Innovative approaches to canulation and blood flow direction

In addition to new cannula designs, there have been notable advancements in canula configurations and blood flow direction through dual lumen cannulas. The Protek Dual cannula, with its canula-within-a-cannula design, allows for percutaneous, single venous access at the right internal jugular vein. This design facilitates right atrial blood drainage and pulmonary artery blood return. The literature reports successful applications of this cannula as a pulmonary artery drainage method for left ventricular unloading. Furthermore, it has been used as a double return cannula in a V-VP configuration. Additionally, the Protek Dual cannula has been employed in a left ventricular-aorta configuration, in combination with a centrifugal pump, serving as an effective left ventricular assist device (LVAD).^14–17

Left ventricular unloading

Left ventricular unloading plays a crucial role in supporting myocardial recovery in venoarterial (VA) ECMO. While conventional unloading techniques like IABP, Impella, and direct left ventricle cannulation are well-known, there is an ongoing search for more effective, cost-efficient, and less hemolytic unloading strategies. The IVAC2L® (PulseCath) and I-cor® (Fresenius) devices offer pulsatile flow synchronized with the patient's electrocardiogram, assisting in left ventricular unloading by reducing afterload during the end-diastolic phase. These devices, utilizing pneumatic (IVAC2®) or electronically driven (I-cor®) pulsatile flow technology, have shown promising results when combined with VA ECMO. However, further investigation is needed to determine optimal patient selection, flow rates, pulse pressures, cannula types, and the potential for hemolysis.^18–20

Safe transport of ECMO systems

Safe transport of ECMO systems has become increasingly important for transferring patients between hospitals and specialized centers. The Cardiohelp® (Getinge) has been considered the gold standard in terms of transportability. However, newly FDA and CE-approved transport systems, such as the Quantum Transport System® (Spectrum Medical) and Colibri® (Eurosets), also effectively address this need by providing lightweight devices with enhanced safety and monitoring features.^21,22

Additionally, there are some recently introduced basic ECMO pump steering devices like the LifeSPARC® System (LivaNova) and Breethe OXY-1 System® (Abiomed) which facilitate patient mobilization but have limited safety and monitoring capabilities. Both are 510 (k) cleared devices without CE marking. FDA recalls and software updates highlight here the ongoing importance of reporting, and need for device optimization and regulatory oversight.^23–25

Standardization of ECMO systems

To address the lack of uniformity in ECMO systems across countries, the Anivia Extracorporeal System® (Asia Pacific Medical Technology Development) has been introduced to the ECLS market. This centrifugal speed control device with a touch screen interface enables the control of different centrifugal pumps available on the market. This standardization solution allows for rapid switchover at the bedside and reduces capital equipment expenses. Current compatible centrifugal pumps are the Rotaflow® (Getinge), Affinity® (Medtronic), Biopump (Medtronic) and Revolution® (LivaNova). The console received FDA clearance, no CE marking. ²⁶

Non-invasive circuit pressure monitoring

Monitoring and managing circuit pressures are critical in preventing complications associated with ECMO, such as hemolysis, cavitation, and clot formation. Non-invasive electronical pressure ports integrated into ECMO circuits, such as seen in Xenios® tubing (Fresenius), Nautilus Smart Module® (Medtronic), Cardiohelp® (Getinge), and Colibri® (Eurosets) circuit, offer safer alternatives for traditional invasive pressure monitoring. In cases where pressure monitoring hardware is not available, the Compass Pressure Device®, a disposable vascular pressure device attachable to stopcocks, can provide an acceptable alternatives for invasive pressure monitoring. ²⁷

Controlled automated reperfusion of the whole body

The Controlled Automated Reperfusion of the Whole Body (CARL®), developed by Resuscitec GmbH, focuses on safe and effective reperfusion after cardiac arrest during extracorporeal cardiopulmonary resuscitation (ECPR). This therapy employs pulsatile, ECG-synchronized flow generated by two diagonal pumps, controlled oxygenation using a mobile gas blender, and rapid cooling facilitated by a mobile heater-cooler. Although safety and feasibility have been demonstrated, further investigation is necessary to investigate the clinical outcomes associated with this approach. This device has received CE marking. ²⁸

Retrograde flow through ECMO circuits

An emerging trend in ECMO practice involves the utilization of retrograde flow through ECMO circuits, initially in pediatric cases and subsequently in adults. This approach aims to avoid incorporating an additional bridge in the circuit (pediatrics) and to provide preload to the right ventricle during weaning trials (adults). Despite technical considerations and alerts from engineers and perfusionists, more centers are adopting this technique. However, concerns regarding flushing back potentially accumulated circuit clots or embolic load remain unresolved.^29–32

Encouraging cooperation between the clinical, technical and commercial brains

With the realization of the importance of translational science in ECLS, EuroELSO has strengthened its relationship with some of its stakeholders. Firstly with the industry, by encouraging interaction and offering consultancy regarding device related decisions. Secondly, a more tight bond with engineers and perfusionists has been established which is visible by their active presence at the technological oriented meeting sessions and their participation in the EuroELSO Devices and Technology committee.

Conclusion

This manuscript highlights some recent innovations in ECLS-related technologies and techniques, and emphasizes the importance of identifying and addressing technological deficiencies in healthcare.

In both the United States and Europe, ECLS devices are generally classified as medium-risk devices, except for ECMO cannula. In Europe, ECMO cannula are upgraded to Class III or high-risk devices, which necessitate more comprehensive investigations. If it can be demonstrated that new devices are similar to previously approved devices, FDA clearance for them can be expedited. Due to the relatively limited clinical investigation required for medium-risk devices and the expedited 510(k) procedure, post-market surveillance and reporting play a critical role. All stakeholders must take their responsibilities in this regard seriously.

We also witness worldwide a substantial unlabeled use of ECMO related technology in terms of extended usage terms, non-validated ECMO circuit compositions and off label practice.

Collaboration between medical professionals, researchers, and engineers is crucial for designing new solutions and improving existing products, but also to investigate off label practice. By fostering this collaboration and reporting technological shortcomings, the quality of care in technology-dependent medical domains can be enhanced.