Pressure ulcers, also called bedsores, occur when the identical spots on an individual’s pores and skin are squashed for too lengthy, slicing off blood circulation and killing tissue. Today’s alternating-pressure mattresses strive to cease this by gently inflating and deflating air-filled sections so nobody patch of pores and skin stays underneath pressure.
But many of those beds merely goal to cut back the height pressure and the outcomes have been combined.
In a brand new examine, researchers from the University of California Los Angeles requested a shocking query: what if one of the best ways to cease ulcers is to increase the height pressure for brief durations, then drop it, somewhat than protecting it low on a regular basis?
The workforce constructed a full-sized analysis bed containing 1,260 small electrical rams. Each ram might rise or drop by up to 10 cm, permitting the floor to type a chess board of hills and valleys that might flip forwards and backwards.
Then, utilizing an anatomically appropriate 100-kg dummy, a skinny foam pad, and an digital pressure-mapping mat, they recorded the pressures underneath the again, hips, and heels for a lot of patterns of hills and valleys. During this, they tracked the hill-to-hill spacing and the depth.
For every sample they calculated the entire space of pores and skin that stayed above the blood cut-off pressure, about 32 mm (Hg). They additionally checked how delicate this space was to individuals who have barely larger or decrease private cut-off pressures, from 20 to 40 mm (Hg).
The knowledge revealed that patterns with larger peak pressures truly diminished the world above the cut-off and that bigger pressure variations between the elements with and with out pressure helped too. In truth, the workforce discovered the candy spot to be a sample with a 12-13 cm hole between hills and a 2.5 cm distance between valley bottoms and hill tops.
Finally, the researchers constructed an actual mattress with versatile plastic panels joined by skinny metallic strips. When somebody lay on it, the panels snapped right into a steady sample. A mild push or a small motor underneath the equipment might flip it to a second steady form. This was achieved with the assistance of balancing springs that countered the particular person’s weight, such that switching between the 2 shapes required solely about 85 N of pressure, or lower than 10% of a 100 kg person’s weight.
With the dummy mendacity flat, the brand new mattress diminished the world underneath the cut-off by an element of 34 relative to a daily 160 sq. cm hospital foam pad. The space additionally modified little or no when the cut-off was shifted from 20 to 40 mm (Hg), that means it might work for a lot of physique sorts.
In 60 trials, the workforce might flip the mattress reliably with an 85-N pull, indicating that the spring-assisted design could be sensible for healthcare staff to function.
The findings have been printed in Science Robotics on June 18.
