Given the number of device applications that involve the transfer of a gas or liquid, it is no wonder pump technology is such a significant part of many healthcare-related products. In addition, pumps are not exempt from the trends of miniaturization and cost reduction. As such, this article takes a look at how today’s medical device demands are being answered by advanced pump technology.
In medical design, transferring media—be it oxygen, a patient’s sample or fluid for analysis within an IVD device—is dependent on the pump (sometimes referred to as the “heart” of the application). Engineers entrusted with the task of designing medical devices must select pumps on criteria that now include device miniaturization and cost reduction. Fortunately, advances in pump technology are helping engineers meet these criteria and bring additional value by optimizing performance in ever-shrinking designs.
Smaller Size, Bigger Performance
Since day one, component quality has been of utmost importance in medical designs. Today, miniaturization and application flexibility are paramount for components—without any loss in performance or reliability. This includes pumps, where a reduced footprint is required without sacrificing the ability to transfer media consistently.
Designs are not the only aspect of medical devices that are shrinking. Costs are continually scrutinized, and as a result, budgets are not what they used to be. The days of the “blank check” no longer exist, so engineers must select the most cost-efficient pump. A key aspect in that choice is to work with an experienced, knowledgeable pump manufacturer early on so the best pump for the application is used or created.
Working with this type of pump manufacturer may allow for a pump to be tailored specifically to a design. Customization doesn’t necessitate an expanded budget; it doesn’t correlate to extended timelines either. One reason for this is that some pumps now utilize modular designs, incorporating a uniform “block.” Medical design engineers and the pump manufacturer can work together to build the sub assembly and pump according to the specifications required. Often, this process doesn’t just boost performance; it reduces design cost, as the engineer will specify a pump perfect for the application rather than a more expensive model.
An additional trend that has helped meet the smaller-design, less-expensive mandate is the development of brushless DC (BLDC) motors, which have numerous advantages over AC-driven equipment. BLDC allows flow rates to be adjusted as needed, helping to extend the lifecycle and reliability of the device. The ability to adjust to slower speeds also helps to reduce audible noise, a valuable benefit of today’s miniature designs. Another advantage in the miniaturization trend, BLDC motors operate at 12 or 24 V, much lower than AC motors that operate at 115 to 230 V, which significantly reduces heat generation. BLDC motors, with their lower operating voltage, also help create a global chassis that streamlines the system-level regulatory agency approvals as one design can be used worldwide. Select pump manufacturers have developed their own BLDC motors, which brings customization advantages as well.
For these reasons, a large variety of pumps now utilize BLDC motors. Large format pumps, such as the one shown in Figure 1, utilize BLDC technology that reap benefits in a myriad of medical settings. For example, they are used in aspiration systems to evacuate waste and protect samples from becoming contaminated. Efficient and worry-free aspiration enables improved health systems for patients. On the other end of the pump footprint spectrum are micro-diaphragm pumps (Figure 2), which are extremely compact, yet deliver king-sized performance. They prove extremely useful in designs such as anesthesia monitoring, playing a crucial role in analyzing the content of patients’ exhaled air, helping ensure the required precision measurement.
Digital control is an emerging trend that helps create higher-level system control. Utilizing soft-start and other electronic features, pumps can detect changes in the overall system and respond with automatic adjustments, extending component life, improving reliability, and optimizing performance of the entire system.
Not Just a Pump, but a Relationship
With such rapid evolution, medical design engineers often cannot keep up. Integrating the wrong pump into an application can provide drastic effects on necessary fluidic and pneumatic functions within the system. Therefore, it is critical to work with a pump manufacturer with the depth of knowledge needed for unique applications, while remaining open-minded to learn the nuances of the setting.
In fact, an OEM pump manufacturer should be a part of the process from first product touch to last, and even far after. This consultative approach doesn’t just optimize the efficiency of the pump; it provides a total system solution and risk mitigation factor for the design engineer. It also provides efficiency aspects, as engineers can focus on other elements of their design while having confidence that the pump manufacturer can help specify the pump, ultimately leading to a better final product.
The Value of the Right Choice
Adding value is now expected at every step of the design process. Making the right choice while integrating components saves costs down the road; however, making the wrong choice during these critical steps often leads to rework, and potentially monumental re-design costs. Expectedly, a properly integrated pump running at optimal efficiency is a major step toward achieving an entire system that will operate at ideal conditions.
Simultaneously, incorporating the pump manufacturer early into the process can also benefit the pump itself. Well-designed BLDC diaphragm pumps correctly integrated into an application can boost product lifecycles, lasting more than one billion strokes. Therefore, as power consumption becomes a priority and control via electronics is maximized, costs can be reduced when compared to traditional methods of AC pump operation.
The Pulse Behind the Process
Allowing the pump manufacturer to work alongside the design team from the start often leads to continued product and process improvement, while maximizing component lifecycles. In medical design, where pumps are often tasked with life-saving responsibilities, a product must reliably and efficiently transfer air, liquid, gas, or slurry. Failure to do so can immediately affect the diagnostic, and ultimately impact the health of a patient. Therefore, it is key to develop a relationship with the pump manufacturer in which they can provide analysis and modification to the system if needed, helping it remain efficient and cost friendly through the course of its application.
The trend towards miniaturization has led to innovations in pumps to accommodate the smaller medical device designs. Engineers responsible for those designs should not only consider pumps incorporating these advances but also collaborate with pump manufacturers with a commitment to engineering early in the design stage. The result will be the use of pumps that address the specifications but can also optimize performance and reduce design costs.