Toothpaste-like gel stems excessive bleeding

A new toothpaste-like hydrogel could one day save haemorrhaging patients – even those on blood-thinning medication.

Reginald Avery and Ali Khademhosseini, biochemists at Harvard Medical School in the UK, and colleagues developed a biomaterial that stemmed excessive bleeding and successfully tested it on pigs.

They unveiled their work in Science Translational Medicine.

Patients experiencing uncontrolled bleeding – from an aneurysm or due to injury or trauma – face a 40% death rate.

The current treatment for excessive bleeding is to block the open blood vessels using metallic coils, popped in with a catheter, to induce clotting (called thrombosis).

But it only works in patients with good blood-clotting abilities, spelling danger for those on blood-thinning medication. The procedure is also a technical procedure that requires high levels of expertise.

So Avery, Khademhosseini and colleagues developed a hydrogel, known as a shear-thinning biomaterial, which combined synthetic silicate nanoplatelets and gelatin.

Once injected using a catheter, the gel clogs the blood vessel, blocking the flow of blood. The material is strong enough to withstand pressure without moving and naturally degrades over time.

When tested on pigs, which have similar-sized blood vessels to humans, the gel successfully blocked bleeding for up to 24 days – even in pigs without the ability to clot blood.

“This work is an example of how bioengineering can help address the challenges that clinicians and patients face,” Khademhosseini says.

“Our work thus far has been in the lab, but we are on a translational path to bring this new biomaterial for embolisation to the clinic to improve patient care.”

Because the gel is made from materials already used in humans, the process to get this technology into the clinic should be faster than usual, the researchers write.