http://orcid.org/0000-0001-9747-5683
To Dr. Scherer,
My name is Bob Graebe. I hold a degree in electrical engineering. I am writing this letter to offer some perspective on a problem that I have been trying to solve for 60 years. Dr. Arthur Heather introduced me to the problem of bedsore, or decubitus ulcers, as they were called in the 1950s.
I introduced a disruptive concept into support device design in 1958 by changing performance goals from pressure relief to shape fitting to minimize ischemia. It is my opinion that ischemia is a cause of cellular death. I designed a support device that synthesized all of the floatation properties of a fluid by creating a matrix of pneumatically interconnected air cells that arrange to create a seat that makes a unique shape fitting support surface. From concept to salable product, it took me over 20 years of part-time self-taught biomedical engineer and garage work. Persistence and science won in the end.
Many of you are familiar with the ROHO® air floatation cushion (now sold by Permobil) that was produced as a result of this effort. And while the ROHO® cushion has gone on to prevent and help heal many pressure injuries (as they are now called), we have not eliminated the problem and our work is not complete. Pressure injuries still occur, and I maintain that it is a failed engineering solution, not a failed medical problem.
As the current generation of engineers try to understand the development of pressure injuries and prevent pressure injury development, your first goal must be to avoid getting distracted by the name “pressure injury” and understand that the external pressure alone is not responsible for the pressure injury.
The external pressure leads to a cascade of pathophysiological responses inside the body, many of which begin when the tissue displaces relative to the bony skeleton and changes shape or strains. These changes also lead to occlusion of blood flow and lymphatic flow, all of which work together to lead to tissue damage and ultimately cell death. We know that the amount of tissue change caused by the external pressure and the likelihood of tissue damage differs according to an individual’s deformation resistance, and it is vital that we figure out how to measure which people have the lowest deformation resistance and need the most attention in terms of preventing pressure injuries.
In the past 60 years, this field has not seen any disruptive ideas to support pressure injury prevention. I encourage the current generation of young engineers to use the same level of persistence and devotion to science that I struggled with in my garage for 20 years to break through and solve the engineering problem of pressure injuries, and in turn to improve the lives of many people at risk of developing pressure injuries.
Disclosure statement
No potential conflict of interest was reported by the authors.