A baby’s heart rate is an indicator of their respiratory status and an important factor to watch closely. If a newborn requires lung ventilations but does not receive it in time, the infant might pass away. The traditional method of detecting a newborn’s heart rate is by using a stethoscope which makes it quite difficult to continuously monitor. Laerdal Medical collaborated with Materialise to co-create an easy-to-use, easy-to-manufacture NewBorn Heart Rate Sensor that helps medical staff see when the newborn needs medical attention.
Karel Honings from Materialise worked with Øystein Gomo from Laerdal Medical to go from idea, to prototype, to manufacturing the final product. Øystein had prior knowledge of vacuum casting, and came to Materialise because of their expertise and engineering consultancy services. “For me as a product developer it was important to cooperate with a company that has skilled and experienced people to perform the vacuum casting”, explains Gomo. “For us it was not only a question of getting an accurate and smooth surfaced master model, but also to cast prototypes that were going to be used directly onto vulnerable patients in their very first minutes of life in this world.”
Continuous Improvements with Rapid Prototyping
Laerdal wanted a monitor without any small gaps or holes. This makes it easier to sterilize and prevent bacteria from getting trapped inside the medical device. Materialise’s approach, by using 3D-printed masters for vacuum casting, allowed going from flexible prototype design to high-quality end parts in an optimum development process.
First, the initial idea went from CAD model to stereolithography prototype. Thanks to 3D Printing, the team was easily able to make several prototypes of the model, improving on the design in each iteration. Both Laerdal and Materialise were committed to ensuring that this monitor would fit newborns exactly, and would not be too tight or too loose for newborns of varying sizes.
The Easiest Route from Prototype to Final Product
Once the final design had been established, the 3D-printed model directly served as master for a vacuum-casted inner shell. After placing the PCB, spring sensor and wiring, the outer shell was casted, resulting into a seamless product with absolutely no small holes.
“The process of in-molding mechanics, cabling, and highly sensitive electronics in plastic was not a straight forward task, but worked out nicely due to a close and direct cooperation between us at Laerdal Medical and the highly competent and dedicated mold makers at Materialise.”
– Øystein Gomo
This monitor will mainly be distributed in developing countries, along with people to train clinicians on how to use the sensor. There is a partnership between Norwegian and Tanzanian medical scientists who are using the data from this heart rate monitor to come up with ways to keep newborns healthy.