Wearable Extracorporeal Membrane Oxygenation System for Safer Patient Ambulation

Saturday, October 11, 2025

8:55 AM - 9:00 AM PDT

Location: Room 30B

Presenting Author(s)

Lawrence W. Li

Undergraduate Researcher
Vanderbilt University
Clarksburg, Maryland, United States

Co-Author(s)

SB

Sriya Bapatla

PhD Student
Vanderbilt University, United States
GG

Gabriella Glomp

Research Assistant
Vanderbilt University
Evanston, Illinois, United States
Colleen Burke

Undergraduate Student Researcher
Vanderbilt University
Chicago, Illinois, United States

Last Author(s)

Rei Ukita, PhD

Research Assistant Professor, Cardiac Surgery
Vanderbilt University Medical Center
Nashville, Tennessee, United States

Primary Investigator(s)

Rei Ukita, PhD

Research Assistant Professor, Cardiac Surgery
Vanderbilt University Medical Center
Nashville, Tennessee, United States

Co-Author(s)

AK

Andrew R. Kumpfbeck

Post Doctoral Research Fellow
Vanderbilt University Medical Center, United States
YW

Yerin Woo

Postdoctoral Researcher
Vanderbilt University Medical Center, United States

Introduction: : Extracorporeal membrane oxygenation (ECMO) is a mechanical circulatory support system for patients with cardiopulmonary failure. Its use is expanding rapidly: North American centers performing >20 venovenous ECMO cases annually increased from 29% pre-COVID-19 to 41% during the pandemic.

ECMO is often used to bridge patients with end stage lung disease to lung transplantation. By draining venous blood from the patient, pumping it through an oxygenator, and returning oxygen-rich blood to the body, ECMO helps patients maintain adequate oxygenation without mechanically ventilating and stressing their native lungs. Though patients are traditionally sedated on ECMO, recent data suggests that ambulation decreases length of hospital stay, improves patient strength, quality of life, and results in better lung transplant outcomes. Despite the indications to ambulate ECMO patients, current clinical systems are cumbersome and heavy (Fig. 1), requiring at least three clinical staff members to safely mobilize a patient. Given the growing interest in exercising an increasing number of ECMO patients, there is a dire need to innovate on lightweight, ambulatory ECMO systems.

We present a 3D printed wearable ECMO pump driver that weighs less than 3 kg. The modular design supports universal compatibility with other pump heads. The system is optimized for portability while maintaining the ability to deliver clinically relevant pressures and flows, offering a solution to the limitations of traditional bedside ECMO setups.

Materials and

Methods: : Our two-piece design (Fig. 2) supports a DC motor, a magnetic coupling disc, and a clinical centrifugal ECMO pump (Spectrum, CP22V-VT). The cap attachment seats the pump, and a motor casing encloses the motor and magnetic disc. A "twist-to-lock" mechanism couples the cap and pump to the disc in the motor casing. The components were designed in SolidWorks and 3D-printed in polylactic acid (PLA). Ideal magnetic coupling was determined when the highest circuit pressures and flows were obtained.

To assess hydraulic performance of the driver, 1 liter of 50% glycerol solution with similar viscosity to blood was pumped through a benchtop circuit consisting of 3/8” medical tubing, a reservoir bag, and a Hoffman clamp to modulate circuit resistance. The pump input voltage was set from 12-30V, current draw and pump speed in revolutions per minute (RPM) were recorded, and then circuit flow was decreased in 0.5 L/min increments using the Hoffman clamp until flow reached zero. Pressure flow (HQ) curves and power consumption were then computed to achieve relevant clinical ECMO operating conditions of >4 L/min of flow and >250 mmHg of pressure head.

Hemolysis of the pump operated by our driver was compared to a different centrifugal pump and its clinical console, Rotaflow. Circuits identical to those used for assessing hydraulic performance were filled with six hundred milliliters of bovine blood. ECMO conditions of 4 L/min and 300 mmHg were held for 6 hours. Blood samples drawn at every hour were analyzed to determine normalized index of hemolysis (NIH).

Results, Conclusions, and Discussions:: Pressure flow curves (Fig. 3) demonstrate that the Spectrum pump and wearable ECMO driver readily achieve flows of 0–9.5 L/min and pressure heads of 24–357 mmHg (N=3). The driver is capable of operating at clinically relevant ECMO conditions for at least 6 hours without experiencing decoupling events, loss of pressure head, or inconsistent flow issues. Power consumption of the DC motor (in watts) recorded at every pressure-flow point indicates that 17-19W were necessary to maintain ECMO conditions (Fig 3). Additionally, the “twist-to-lock” design for the pump driver proved to be lightweight ( < 3 kg) and robust. The cap attachment did not come loose or cause decoupling issues during testing.

Hemolysis testing determined that the NIH of the wearable ECMO driver was 0.004 g/100L (N=1), a value comparable to the NIH of 0.003 g/100L (N=1) of the clinical Rotaflow console.

Our robust and low-profile wearable ECMO pump driver pushes wearable ECMO technology in the direction of better facilitating ambulatory use. This lightweight driver capable of maintaining clinically relevant flows is a suitable choice for powering a wearable ECMO system. A preliminary hemolytic study suggests that the pump driver is a safe alternative to current clinical consoles. Future work also includes selection of a battery based on power consumption of the motor at clinical ECMO conditions. Additionally, integration of the pump driver into a wearable circuit with tubing, oxygenator, batteries, and a user interface will bring the wearable ECMO technology closer to clinical translation. This platform will also be used to test closed-loop controllers with the goal of automating ECMO.

Acknowledgements and/or References (Optional): : Milewski, Rita C et al. “ECMO During COVID-19: A Society of Thoracic Surgeons/Extracorporeal Life Support Organization Survey.” Annals of thoracic surgery short reports vol. 1,1 (2023): 168-173. doi:10.1016/j.atssr.2022.10.017

Kourek C, Nanas S, Kotanidou A, Raidou V, Dimopoulou M, Adamopoulos S, Karabinis A, Dimopoulos S. Modalities of Exercise Training in Patients with Extracorporeal Membrane Oxygenation Support. J Cardiovasc Dev Dis. 2022 Jan 20;9(2):34. doi: 10.3390/jcdd9020034. PMID: 35200688; PMCID: PMC8875180.

Abrams, D., Javidfar, J., Farrand, E. et al. Early mobilization of patients receiving extracorporeal membrane oxygenation: a retrospective cohort study. Crit Care 18, R38 (2014). https://doi.org/10.1186/cc13746

We'd like to acknowledge the funding sources for this research: Vanderbilt University Center for Technology Transfer and Commercialization: Innovation Catalyst Fund, the VUSE Summer Research Program, the Vanderbilt Institute for Surgery and Engineering, the Wond'ry at Vanderbilt University, and Anderson Meats and Processing.