In-Bed Ergometer

An assistive cycling device to allow mobilization of bed-bound patients in the ICU.

Background and Problem Statement

• More than 5 million people are admitted to ICUs in US/year¹
• Immobility during ICU stays leads to complications²: including
  • ICU-acquired weakness
  • Long-term disability
  • ICU-associated delirium
  • Higher rates of mortality
  • Longer ICU stays
• In-bed cycling ergometry is a safe and effective intervention for ICU patients^{3, 4}
• Early mobilization has been found to:
  • Decrease one-year mortality rates⁵
  • Decrease prevalence of psychiatric conditions after ICU discharge
  • Improve hyperglycemia⁷

Problem Statement: ICU patients who are unable to leave their beds without assistance may benefit from increased access to mobility; however, the time required for ICU PTs to exercise patients frequently and the cost of current in-bed cycling ergometers pose a barrier to improving patient outcomes. We are tasked with creating a device that allows patients to move through an assisted cycling motion with their lower limbs from bed at a more accessible price point, allowing patients to reap the benefits of early mobility without needing to be able to leave their beds.

Design Process

Key Design Features

Assistive Cycling	The motorized design allows for the patient’s legs to be moved through a cycling range of motion without using their own muscle power.
Orthotic Boot Foot Attachment	The orthotic boot secures the patient’s foot into the device and comes in a range of sizes. It can also be inflated to provide a tighter fit.
Lockable Wheels	Lockable wheels allow for easy maneuverability through the ICU and for stability while in use.
Collapsible Design	The legs fold up and the boom folds down to decrease the footprint of the device and make storing it in a crowded ICU easier.
Control Panel	The control panel allows the operator to change the direction and speed of movement and track the speed and time spent using the device.
Adjustable Height	The boom can be raised and lowered to adapt to various bed dimensions and patient needs and allow for easy storage.
25 ft Power Cord	No need to charge batteries, the 25 ft power cord will easily plug into the many outlets in the ICU.

Final Prototype

Future Directions

• Enclose belts and motor
• Round edges of device
• Create lower profile foot pedals
• Enclose hydraulic lift
• Create vinyl lining for orthotic boots

Design Team

Megan Bell, Paul DeSouza, Johann Kintzel, and Matthew Tierney

Supervisor: Dr. Cherice Hill, PhD

Project Management Liaison: Amanda King

Customers

Acknowledgements

We would like to acknowledge the following people for their assistance throughout the semester with this project:

Tracy Hardes, Joe Crumlish, Dr. Scott Seidman, Dr. Ben Castañeda, Dr. Cherice Hill, Jim Alkins, Samantha Kriegsman, Martin Gira, and Shawn T. Biehler

Sources

1. Society of Critical Care Medicine (2024). Critical care statistics. [online] Society of Critical Care Medicine (SCCM). Available at: https://www.sccm.org/Communications/Critical-Care-Statistics.
2. Schweickert, W.D., Pohlman, M.C., Pohlman, A.S., Nigos, C., Pawlik, A.J., Esbrook, C.L., Spears, L., Miller, M., Franczyk, M., Deprizio, D., Schmidt, G.A., Bowman, A., Barr, R., McCallister, K.E., Hall, J.B. and Kress, J.P. (2009). Early physical and occupational therapy in mechanically ventilated, critically ill patients: a randomised controlled trial. The Lancet, [online] 373(9678), pp.1874–1882. doi:https://doi.org/10.1016/s0140-6736(09)60658-9.
3. Takaoka, A., Utgikar, R., Rochwerg, B., Cook, D.J. and Kho, M.E. (2020). The Efficacy and Safety of In–Intensive Care Unit Leg-Cycle Ergometry in Critically Ill Adults. A Systematic Review and Meta-analysis. Annals of the American Thoracic Society, 17(10), pp.1289–1307. doi:https://doi.org/10.1513/annalsats.202001-059oc.
4. Nickels, M., Aitken, L., Walsham, J., Barnett, A. and McPhail, S. (2019). 129. Critical Care Medicine, 47, p.47. doi:https://doi.org/10.1097/01.ccm.0000550886.33140.92.
5. Wieske, L., Dettling-Ihnenfeldt, D.S., Verhamme, C., Nollet, F., van Schaik, I.N., Schultz, M.J., Horn, J. and van der Schaaf, M. (2015). Impact of ICU-acquired weakness on post-ICU physical functioning: a follow-up study. Critical Care, 19(1). doi:https://doi.org/10.1186/s13054-015-0937-2.
6. Watanabe, S., Liu, K., Nakamura, K., Kozu, R., Horibe, T., Ishii, K., Yasumura, D., Takahashi, Y., Nanba, T., Morita, Y., Kanaya, T., Suzuki, S., Lefor, A.K., Katsukawa, H. and Kotani, T. (2022). Association between Early Mobilization in the ICU and Psychiatric Symptoms after Surviving a Critical Illness: A Multi-Center Prospective Cohort Study. Journal of Clinical Medicine, 11(9), p.2587. doi:https://doi.org/10.3390/jcm11092587.
7. Patel, B.K., Pohlman, A.S., Hall, J.B. and Kress, J.P. (2014). Impact of Early Mobilization on Glycemic Control and ICU-Acquired Weakness in Critically Ill Patients Who Are Mechanically Ventilated. Chest, 146(3), pp.583–589. doi:https://doi.org/10.1378/chest.13-2046.