ENGINEERINGSOLUTIONS: MDEA
Now in its 12th year, the Medical Design Excellence Awards (MDEA) recognize innovation
by medical device manufacturers and their suppliers. In this special edition of our Engineering
Solutions section, which typically highlights a case study, MPMN covers the design and
development process of six of this year’s 32 MDEA-winning products. Gold and silver distinctions
will be awarded at the MD&M East trade show event in New York City.
Visit devicelink.com/mpmn/mdea now for a complete list of winning products and bonus information.
Plus, check back with us after the trade show for Web-exclusive coverage of the awards ceremony.
System Helps Cardiac Arrest Patients Chill Out
Beginning this year, New York
City joins a growing number of
cities that require ambulances to
take cardiac arrest patients only to
those hospitals equipped to induce
therapeutic hypothermia. Endorsed
by the American Heart Association
and gaining popularity, therapeutic
hypothermia is the rapid cooling
of the body to minimize potential
neurological damage caused by
oxygen deprivation of a cardiac
arrest patient’s brain.
But despite demonstrated
efficacy, the cooling process has
been somewhat slow to catch on
owing to precise temperature
regulation requirements and a lack
of sophisticated equipment. Life
Recovery Systems HD LLC (LRS;
Waldwick, NJ; www.life-recovery.
com) is looking to change that with
the ThermoSuit body-cooling system,
one of this year’s MDEA-winning
products. The ThermoSuit system
is designed to rapidly cool a
patient’s core temperature to 33°C
in 20 minutes or less.
“To our knowledge, it’s the only
[product] that cools with thin-film
liquid convection,” says Robert
Schock, LRS vice president of
R&D. “We pump cold liquid—in
this case cold water—over the
body in a thin layer and move it to
extract heat from the skin. This
is a really effective way to extract
heat from the body compared with
conventional cooling blankets and
ice cubes.” Conventional methods
typically feature a layer of material
that separates the skin from direct
contact with the coolant, thereby
creating thermal resistance,
according to Schock. “Direct moving
liquid seems to extract heat at least
six times [faster than] if you have
one of these plastic boundary layers,”
he adds.
Ensuring direct skin-to-water
contact in the ThermoSuit is a
body enclosure, manufactured
by thermoplastic medical device
specialist Dielectrics (Chicopee, MA;
www.dielectrics.com). The inflatable,
porous-batting-lined tub is designed
with a self-adjusting sling system that
adapts to a patient’s shape and size
for optimal cooling. Dielectrics also
created a plastic sheet that sprays ice
water on the front of the patient for
even distribution of coolant over the
entire body. “That involved [radio-frequency] welding a network of
channels with perforations in them
making up the top cover, which
is draped over the top of the suit,
and selecting a material that would
actually drape and contour over the
body’s surfaces,” explains Adam
Epstein, Dielectric’s vice president
of R&D. The company elected to
use thermoplastic urethane for its
biocompatibile and stretchable
nature, as well as for its stability
amid extreme temperature changes.
For assistance with the industrial
design of the control unit and
disposable interfaces, LRS turned
to Ximedica (Providence, RI; www.
ximedica.com), a full-service medical
“Up until this device,
there was never a
practical way to do this
in an ER setting without
making a mess.”
—David Robson
device design and engineering firm.
Among its contributions to the
ThermoSuit is a complex hose that
connects the suit enclosure with the
control unit. Although simple to use,
the connecting hose features five
lines: two water inlets, two air inlets,
and a water outlet to regulate the air
and water in the suit. In addition,
the company developed a gear drive
system designed to actually pump
water out of the suit in a worst-case
scenario from roughly 20 in. away—
an action for which many pumping
methods are not suitable, according
to David Robson, Ximedica’s vice
president of development.
Recruited for engineering the
system responsible for pumping
the water into the suit,
Nexcore Technologies
Inc. (Waldwick, NJ; www.
nexcoretech.com) lent its
expertise to a number of
mechanical and electrical
engineering tasks, as well
as software development. “They
had expertise in designing new
pumping systems with monitoring
functions and valving systems,
which were needed to inflate
the suit with air and regulate the
different air pressures,” recalls
Schock. Configured to operate at
the optimal flow rate of 14 L/min
for rapid cooling, the pump system
manufactured by Nexcore consists
of two water pumps, an air pump,
regulating valves, and a computer
controller.
“The other challenge was to
make it almost foolproof for the
end-user, so the software guides
the user through each step of the
procedure,” adds Milton Frank,
Nexcore president.
In addition to simplicity, Nexcore
focused on engineering the software
for safety. For example, the software
safeguards a patient from being
overcooled. Although physicians have
the option to end the procedure at
any time, the unit signals when the
patient’s core body temperature,
taken by an esophageal temperature
probe, approaches the preset target
temperature. “If they don’t take
care of that within a minute, the
system will automatically purge the
water out of the suit and into the
reservoir,” Frank says.
The ThermoSuit body-cooling system is
designed to rapidly cool a cardiac arrest
patient's core temperature in order to
prevent neurological damage.
representation of body temperature
on the screen over time,” Robson
notes. “This provided them with an
extra measure of confidence that
the desired clinical effect was being
accomplished.”
In response to extensive user
research, the team designed the
system to keep working even after
the cooling process is complete.
“Through discussions with doctors,
even though the device automatically
regulates treatment
based on the patient’s
core temperature, it was
clear that they wanted to
be able to see a graphical
Confidence is something that
the development team behind the
ThermoSuit has in its MDEA-winning
device. “Up until this device, there
was never a practical way to do this
in an ER setting without making a
mess,” Robson says. “This has been
the first really practical, really fast
way to address this kind of emergency
situation.” –Shana Leonard
For a complete list of
MDEA-winning products
and bonus coverage of the awards program, go to
devicelink.com/mpmn/mdea
Go to http://www.DEVICELINK.COM/MPMN
