Transport While on Extracorporeal Membrane Oxygenation Support

Complications during extracorporeal membrane oxygenation transfer in Argentina: A multicenter observational study

BACKGROUND

There is a lack of documented cases regarding complications during ECMO transfer in middle-income countries. Using portable ECMO devices facilitates patient transport but entails significantly higher costs, necessitating evidence of their practical utility. This study aims to describe complications during ECMO transfer in Argentina and to compare complication rates between the integrated portable ECMO and non-portable ECMO systems.

METHODS

A multicenter observational retrospective study was conducted across four high-complexity hospitals in Argentina. Patients over 18 years old who underwent ECMO transfer between January 2017 and July 2023 were included. Complications were classified based on the Ericsson severity classification, a widely accepted system that categorizes complications based on their severity and the need for immediate organ support. The effect of the ECMO systems (portable and non-portable ECMO system) on complication rates was assessed using logistic regression weighted by inverse probability weighting (IPWT) analysis after propensity score assessment to adjust for confounders.

RESULTS

The study included 65 patients who were transferred for ECMO. Complications occurred in 40% (95%CI: 28%, 52%; n=26) of transfers, with grade 2 complications being the most prevalent at 20% (95%CI 11%, 32%; n=13). Integrated portable ECMO systems were associated with fewer complications during ECMO transfer, showing a crude OR of 0.25 (95%CI 0.08, 0.75), and after adjustment by IPWT, an OR of 0.27 (95%CI 0.08, 0.93).

CONCLUSIONS

ECMO transfers in middle-income countries exhibit complication rates similar to those in high-income countries. Our study found fewer complications in transfers using integrated portable ECMO systems and those involving distances exceeding 100 km. These findings suggest that the use of portable ECMO systems, despite their higher costs, may be beneficial in reducing complications during patient transport in middle-income countries.

A Simulation Curriculum for Ground and Air ECMO Transport

Introduction

The use of extracorporeal membrane oxygenation (ECMO) for cardiopulmonary failure is increasing. ECMO transport teams are needed to expand patient access. Our goal was to design and implement a simulation curriculum for an ECMO transport team.

Methods

Using Kern's model, we developed a curriculum, built an ECMO protocol, and performed a pilot simulation. We conducted a needs assessment survey to evaluate presimulation confidence performing ECMO transport procedures using a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree). We used the results to refine a simulation script encompassing transport logistics, ambulance and aircraft loading/unloading, and emergencies. A simulation mannequin with attached ECMO circuit and all necessary equipment was used to simulate transfer of patients receiving ECMO and to ensure learners could manage in-flight emergencies. After implementation, we distributed a postsimulation survey to assess changes in confidence.

Results

The needs assessment was implemented for four physicians, five ECMO specialists, and 11 flight nurses. The needs assessment revealed 95% of respondents were ECMO transport novices. Mean confidence scores for transporting an ECMO patient were low (3.4). The finalized simulation was implemented for 10 members, eight of which completed the needs assessment and postsimulation surveys. Confidence scores improved overall (3.0 to 4.3) and for emergency procedures: air entrainment (3.0 to 4.6), pump failure (3.3 to 4.6), patient loading/unloading (2.8 to 4.1), and use of transport protocols/checklists (3.5 to 4.8).

Discussion

We successfully developed a simulation-based ECMO transport curriculum, which resulted in enhanced confidence in multiple aspects of ECMO transport.

Adult ECMO in the En Route Care Environment: Overview and Practical Considerations of Managing ECMO Patients During Transport

Purpose of Review

The authors’ experience as a part of the U.S. Military ECMO program to include the challenges and successes learned from over 200 transports via ground and air is key to the expertise provided to this article. We review the topic of ECMO transport from a historical context in addition to current capabilities and significant developments in transport logistics, special patient populations, complications, and our own observations and approaches to include team complement and feasibility.

Recent Findings

ECMO has become an increasingly used resource during the last couple of decades with considerable increase during the Influenza pandemic of 2009 and the current COVID-19 pandemic. This has led to a corresponding increase in the air and ground transport of ECMO patients.

Summary

As centralized ECMO resources become available at health care centers, the need for safe and effective transport of patients on ECMO presents an opportunity for ongoing evaluation and development of safe practices.

Mobile Extracorporeal Membrane Oxygenation for Covid-19 Does Not Pose Extra Risk to Transport Team

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.

Air Medical Transport of Patients Diagnosed With Confirmed Coronavirus Disease 2019 Infection Undergoing Extracorporeal Membrane Oxygenation: A Case Review and Lessons Learned

The coronavirus disease 2019 pandemic disrupted health care delivery in every respect, including critical care resources and the transport of patients requiring extracorporeal membrane oxygenation. Innovative solutions allowing for safe helicopter air transport of these critical patients is needed because extracorporeal membrane oxygenation resources are only available in specialty centers. We present a case demonstrating the interfacility collaboration of care for a patient with coronavirus disease 2019 infection and the lessons learned from the air transport. Careful planning, coordination, communication, and teamwork contributed to the safe transport of this patient and several others subsequently.

Surgical outcomes and complications of bedside tracheostomy in the ICU for patients on ECMO

OBJECTIVE

Extracorporeal membrane oxygenation (ECMO) is increasingly employed in the management of patients with severe cardiac and pulmonary dysfunction. Patients commonly require tracheostomy for ventilator liberation. Though bedside percutaneous tracheostomy is commonly performed, it has the potential for increased complications, both surgical and with the ECMO circuit. We examined surgical outcomes of bedside percutaneous tracheostomy in the ECMO population.

METHODS

Patients were identified from an institutional database for bedside procedures. Demographics and data on complications were recorded. Descriptive statistics were calculated.

RESULTS

37 patients on ECMO at the time of tracheostomy were identified. Median age and BMI were 43.2 and 28.0, respectively. 33 patients (89%) were on VV ECMO, and 4 (11%) were on VA ECMO. All were on anticoagulation prior to tracheostomy, which was held for 4 h before and after the procedure in all cases. There were no procedure-related deaths or airway losses. No patients experienced periprocedural clotting events of their ECMO circuit or oxygenator within 24 h. 3 patients (8%) required reintervention (re-exploration or bronchoscopy) for bleeding. Four other patients (10%) had minor bleeding controlled with packing. One patient had pneumomediastinum which resolved without intervention, and one had an occlusion of their tracheostomy which was treated with tracheostomy exchange.

CONCLUSIONS

Bedside percutaneous tracheostomy is feasible for patients on ECMO. Further study is needed to determine specific risk factors for complications and means to mitigate these. Bedside percutaneous tracheostomy may be considered as part of the management of patients on ECMO to help facilitate liberation from mechanical support.

ECMO Transport without Physicians or Additional Clinicians

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has accelerated rapidly for patients in severe cardiac or respiratory failure. As a result, ECMO networks are being developed across the world using a "hub and spoke" model. Current guidelines call for all patients transported on ECMO to be accompanied by a physician during transport. However, as ECMO centers and networks grow, the increasing number of transports will be limited by this mandate.

OBJECTIVES

The aim of this study was to compare rates of adverse events occurring during transport of ECMO patients with and without an additional clinician, defined as a physician, nurse practitioner (NP), or physician assistant (PA).

METHODS

This is a retrospective cohort study of all adults transported while cannulated on ECMO from 2011-2018 via ground and air between 21 hospitals in the northeastern United States, comparing transports with and without additional clinicians. The primary outcome was the rate of major adverse events, and the secondary outcome was minor adverse events.

RESULTS

Over the seven-year study period, 93 patients on ECMO were transported. Twenty-three transports (24.7%) were accompanied by a physician or other additional clinician. Major adverse events occurred in 21.5% of all transports. There was no difference in the total rate of major adverse events between accompanied and unaccompanied transports (P = .91). Multivariate analysis did not demonstrate any parameter as being predictive of major adverse events.

CONCLUSIONS

In a retrospective cohort study of transports of ECMO patients, there was no association between the overall rate of major adverse events in transport and the accompaniment of an additional clinician. No variables were associated with major adverse events in either cohort.

Changes in Oxygen Saturation and Mean Arterial Pressure With Inhaled Epoprostenol in Transport

OBJECTIVE

Patients with hypoxemic respiratory failure have traditionally been considered one of the riskiest patient populations to transport, given the potential for desaturation with movement. We performed a retrospective cohort study to analyze our experience using inhaled epoprostenol in transport, with a primary objective of assessing change in the oxygen saturation throughout the transport.

METHODS

The transport records of patients with severe hypoxemic respiratory failure or right heart failure, transported on inhaled epoprostenol, were reviewed. The primary outcome was the change in SpO₂ from the start of the inhaled epoprostenol transport to the time of handover of care at the receiving institution. The secondary outcome was the change in the mean arterial pressure (MAP).

RESULTS

Comparing the initial SpO₂ to the final, there was no significant difference in oxygenation between time 0 and the transfer of care at the receiving hospital at 91% versus 93% (interquartile range [IQR] 86.0-93.5 vs 87.5-96.0, P = .49). Comparing the SpO₂ for those who had inhaled epoprostenol started by the transport team showed a larger change at 86% compared to 93% (IQR: 83.0-91.0 vs 86.5-94.5, P = .04). There was no change in the median MAP from time 0 to the end of the transport (77 vs 75 mm Hg, IQR, 67.5-84.8 vs 68.5-85.8, P = .70).

CONCLUSIONS

In this study, patients with severe cardiopulmonary compromise transported on inhaled epoprostenol had no significant change in their median oxygen saturations, with the overall population increasing from 91% to 93%. When inhaled epoprostenol was initiated by the transport team, the improvement was clinically and statistically significant with an increase in SpO₂ from 86% to 93%, with a final oxygen saturation comparable to those who were on the medication at the time of the team's arrival.

Extracorporeal Membrane Oxygenation in Transport Part 2: Complications and Troubleshooting

Factors taken for granted while the extracorporeal membrane oxygenation (ECMO) patient is maintained in a hospital setting can become critical when planning for transport. These issues include but are not limited to positioning of patients on a small transport stretcher, positioning of cannulas and equipment, ensuring adequate power sources and supply, inefficient temperature control, and a much higher risk of decannulation. It is paramount to be comfortable with the management strategies required to handle common complications of ECMO with limited resources in a relatively austere environment. Coagulopathy and bleeding are the most common complications occurring in up to 50% of ECMO patients. Loss of flow and hypotension from loss of volume or profound vasodilation after ECMO initiation need to be managed accordingly. Oxygenator malfunction can occur, and clinicians must be able to recognize the indicators of this complication promptly. Loss of pulsatility, low end-tidal carbon dioxide (ETCO₂), and differential hypoxia are common complications in venoarterial ECMO. In addition, an air embolism is life-threatening on venoarterial ECMO but may be better tolerated in the setting of venovenous ECMO. Recirculation in venovenous ECMO leads to circulation of poorly oxygenated blood and must be recognized and addressed. Lastly, pump failure, circuit rupture, and decannulation are devastating complications. Over the last decade, the use of extracorporeal membrane oxygenation (ECMO) has accelerated rapidly,^1-3 providing support for patients in severe respiratory or cardiac failure. With ongoing clinical experience and improvements in technology, the indications for ECMO are increasing.⁴ Many areas are developing centralized ECMO centers to serve their surrounding communities.^5-7 To use a centralized ECMO referral model, patients need access to effective, safe critical care transport, but transporting a patient on ECMO carries a significant risk of adverse events.^8-13 The purpose of this review is to highlight some of the most common adverse events in ECMO transports and provide management suggestions. Note that these recommendations are not a substitution for close collaboration with medical control, and all adverse events should be promptly reported per organizational protocols.

Outcomes of out-of-hospital extracorporeal membrane oxygenation transfers: significance of initiation site and personnel

BACKGROUND

Extracorporeal membrane oxygenation is an accepted therapy option for refractory cardiac or respiratory failure. The outcomes of cases initiated at non-extracorporeal membrane oxygenation centers and subsequently transported for management to an extracorporeal membrane oxygenation center require further investigation.

METHODS

Retrospective institutional review board-approved database research and chart reviews were performed on referrals for extracorporeal membrane oxygenation initially admitted to an outside non-extracorporeal membrane oxygenation center hospital (OSH) then transferred to our extracorporeal membrane oxygenation center (Thomas Jefferson University Hospital (TJUH)). Unstable patients were placed on extracorporeal membrane oxygenation at OSH (Group A) before transport, while others were initiated at our certified extracorporeal membrane oxygenation center (Group B) upon arrival. Group A was further subdivided into patients cannulated by OSH personnel (Group A_OSH) or TJUH transport team (Group A_TJUH). Outcomes and complications were compared between the different initiation sites and personnel.

RESULTS

A total of 108 patients were transferred from August 2010 to June 2018. The technical complication rate for all Group A patients was 33/49 (67%), while that of Group B was 24/59 (41%); p = 0.006. Within Group A, Group A_OSH had a greater technical complication rate with 29/33 (88%) than Group A_TJUH with 4/16 (25%); p < 0.001. extracorporeal membrane oxygenation survival rate was 34/49 (69%) in Group A and 43/59 (73%) in Group B; p = 0.690. The extracorporeal membrane oxygenation survival rate for Group A_OSH and Group A_TJUH was 21/33 (64%) and 13/16 (81%), respectively; p = 0.210.

CONCLUSION

Promising extracorporeal membrane oxygenation survival rates were observed in transferred patients. The complication rates related to cannulation technique were significantly higher when patients were initiated at non-extracorporeal membrane oxygenation centers, especially when placed by personnel from non-extracorporeal membrane oxygenation centers.

Extracorporeal Membrane Oxygenation in Transport Part 1: Extracorporeal Membrane Oxygenation Configurations and Physiology

Extracorporeal membrane oxygenation (ECMO), a term used to describe oxygenation that occurs outside of the body, is an increasingly common means of supporting the most critically ill patients. Because of the invasiveness and high probability of serious complications during ECMO, ECMO is typically indicated only when there is a high likelihood of death with conventional treatment. With continued improvements in technology and increasing clinical experience, transport clinicians are increasingly likely to be called on to transport patients on ECMO. ECMO can be initiated in 2 distinct forms, venovenous or venoarterial, and can primarily support the respiratory system or the cardiac and respiratory systems concurrently. This review will cover the basic physiology and components of ECMO as well as the preparation for ECMO transport for adults.