A new online simulator developed by the University of Florida’s Center for Safety, Simulation & Advanced Learning Technologies (CSSALT) provides a platform for learning how specific factors can impact non-invasive blood pressure measurement. The Simulation of Blood Pressure Measurement Hydrostatic Artifact* was built at the request of Nikolaus Gravenstein, M.D., the Jerome H. Modell, M.D., Professor of Anesthesiology. It shows the importance of accounting for the height and body inclination angle of a patient as well as the measurement site. Each of these factors can cause changes in blood pressure measurement through hydrostatic pressure.
The simulator was created by UF undergraduate students supervised by CSSALT engineers, Dave Lizdas, BSME, and Chris Samouce, Ph.D. Lizdas explained the new tool. “It conveys a simple concept about blood pressure measurement: the pressure at the location where you place your cuff, like the arm, might be very different from the pressure at the location you care about, like inside the head or at the heart. The context of the cuff’s position matters. It sounds simple, but clinicians use BP all the time in all kinds of patient positions, and it’s important for them to know about this so they can make the right decisions.”
Using a graphical interface, users can interact with the simulator by clicking and dragging the bed to adjust a patient’s angle from 40 degrees head down to 90 degrees vertical. The patient’s height and blood pressure at the heart can also be adjusted. The resulting blood pressure readings at the arm, ankle and head are displayed, allowing users to see the effects of these adjustments on the simulated measurements.
J. S. Gravenstein, M.D., founder of the department of anesthesiology at the University of Florida, used to entertain his med students by standing with a blood pressure cuff on his ankle. “The monitor said his pressure was crazy high, but his students knew he was fine, of course. We’re trying to drive the same point home, online,” said Lizdas. “The difference between what the monitor says and what you need is often something you can work around — it’s just based on vertical distance and hydrostatics.”
This interactive tool allows users to gain a deeper understanding of the complexities of blood pressure management and how various factors can affect the accuracy of readings. The ability to adjust and observe the effects of these factors on simulated measurements in real time provides a valuable learning experience that can enhance the skills and knowledge of medical professionals and students.
*CSSALT’s Simulation of Blood Pressure Measurement Hydrostatic Artifact is best viewed in the Google Chrome browser.