A surgical equipment manufacturer asked us to craft a product that would help physicians maintain consistent vacuum control during surgical procedures such as liposuction. Existing vacuum pressure controllers could not maintain consistent pressure, resulting in a build-up of vacuum pressure during a blockage of the cannula, resulting in a stall of vacuum, followed by an increase in vacuum pressure after the blockage was removed.
An enthusiastic team of engineers began the iterative process of determining the customer's exact usage context so that the solution would be practical, effective and safe. This required collaboration with the manufacturer to verify the required flow rate for the liposuction medical procedure and the vacuum range of interest, which was determined by the cannula orifice-size (.062-.300) and a pump that yielded a 6.8 CFM (cubic feet per minute) of air flow through the system.
The DigiVac team determined that the desired pressure based on the medical procedural needs was anything from 0 to 29.9 inches of Hg (Mercury) with the performance optimized in the 15 inches of Hg range.
During the design process, the manufacturer requested an additional desired feature set that included the need to maintain vacuum pressure:
- When Suction Collection Chamber size changed (either 1, 2, or 3 liters)
- With variable chamber volume (fill capacity) up to 85%—effectively made the range of chamber volumes from 0.15 liters (15% of 1 liter volume) to 3 liters
Other variables included a valve/orifice configuration that satisfied the economic parameters determined by the medical device company. Several valve candidates were identified and these were tested in a simulated liposuction procedure using apple sauce (recommended by client) as the substitute for fatty tissue. See aspiration vacuum control video.
The final product design request was for the customer's need of an aesthetically pleasing as well as quiet system (low Dba). While this might not seem like a necessary feature for many vacuum applications, it is very important for a surgeon (hence our up front emphasis on context and practicality)
The resulting product was a new vacuum regulator: Medical Aspirtation Controller for Liposuction Procedures.