Product design has become a life-and-death issue for processor Mack Group Inc. and a seller of a new medical-infusion pump.
The plastic pump, weighing about 1.2 pounds, replaces a bulkier, cast-iron piece that uses technology invented in the 1970s.
The old unit, used to administer medication during intravenous therapy in a hospital, carries with it some danger, said Mark Semler, drug-administration group leader for medical pump supplier FluidSense Corp. of Newburyport, Mass.
"It has limited functionality," Semler said. "Nurses have to put tape on the display to tell you what drug they are infusing. Around 35 percent of accidental injuries in hospital are due to medication or dosage problems."
That situation brought FluidSense into the pump business. The company had made its living giving seminars and consulting on improving IV therapies. But existing equipment was inadequate, Semler said.
Now, the Massachusetts company has signed an exclusive manufacturing agreement with Arlington, Vt.-based Mack to manufacture the lightweight, digitally controlled infusion pumps. FluidSense plans to sell the pumps and about 10 million disposable cassettes a year that attach to the pump and give accurate dosage readouts.
Mack invested about $2.2 million to build a 2,000-square-foot clean room and add four tie-barless Engel molding machines in Arlington to handle the expected workload. Production on the cassettes will begin in July, and work on the pump housings already has started.
"It looks like a camera that you can hold in the palm of your hand," said Mack business unit director Joan Magrath. "Historically, hospitals have used big, heavy pumps that had no security locks and no controls. The technology was lagging way behind."
The new design, developed jointly by the two companies, was recognized in December by Time magazine as one of the top inventions of 2000.
That design came with its own set of issues, Magrath said. The battery-operated unit, capable of being carried in a fanny pack around a hospital corridor, needed to be both lightweight and easy to hold. The companies took their cue from soft-touch Kodak cameras and the overmolding technology they use.
The housings have a rubber feel, with overmolded thermoplastic elastomer wrapping around the parting lines of the substrate. The substrate was molded from a poly-carbonate/ABS blend.
The overmolded parts also help dampen noise and add impact resistance, Semler said. "You can drop it and bounce it around to no end," he said.
Building the cassettes, which store data used to dispense medicine and keep a patient's history, was new to Mack. A lot of attention went into tooling to ensure stability and balance both cavities and gate design, Magrath said.
The cassette toolmaker, Advance Mold & Manufacturing Inc. of South Windsor, Conn., developed five, eight-cavity molds that hold to the part's precise shape requirements, said Advance project engineer Paul Lapio.
"We got involved even before we had the purchase order, and that gave us a better feeling for the job," Lapio said. "I'd like to think that happens every time on a project."
FluidSense will sell the pumps and let Mack handle the manufacturing side, Semler said. The company, now starting to market the units, has signed four hospitals to use the infusion pumps.
"There are about 5,700 hospitals out there in the United States, so we have a lot of work to do," Semler said. "We plan on a big year."
Meanwhile, Mack has added three 100-ton presses and one 40-ton molding machine in Arlington and will install pressure transducers in each mold to provide information on the condition of the parts.
The company also will add between eight and 24 employees, depending how fast the project ramps up, and use automated processes for sonic welding, leak testing and assembly.
Mack plans to make plastic and metal accessories for the intravenous pump, including a clip-on fluid case and mounting bracket, at its Cavendish, Vt., facility.
The pumps include specialized controls that feature a security system to allow only those with a password the ability to change medicine dosages for a patient.
"We interviewed nurses and doctors before we started and identified the source of most problems and frustrations," Magrath said. "We knew we could improve efficiency and patient care."