I’m your venous: A device to prevent post-surgery blood clots

Ian Bolland sat down with Bernard Ross, CEO of Sky Medical at its office in Daresbury to talk about the Geko device – the device which helps patients' blood circulation.

The device’s primary use is to help prevent patients from getting blood clots. It’s a wearable for the lower part of the leg and stimulates the common peroneal nerve, activating the calf and foot muscle pumps, resulting in increased blood flow in the deep veins of the calf at a rate equal to 60% of walking.  

Explaining the principle behind it, Ross said: “When you use your calf muscle just by walking it naturally expands, but when it expands it can’t go outwards so it squeezes against the veins, the empty space that’s in there, and that pushes the blood out of the vein back up the leg.

“When you walk, you generate venous return. As a species we’re meant to walk around all day and fall asleep.

“There are very few patients in a hospital who won’t benefit from normalising their blood flow because when you’re in hospital your blood flow just drops like crazy. There’s a whole range of things you can try and do, and this is the best one.”

Ross commented that the device was initially the brainchild of Professor Arthur Tucker from St Bartholomew’s Hospital and Dr Duncan Bain.

He explained the gap the duo spotted in the market, saying: “What they discovered is, and they started off looking at deep vein thrombosis (DVT), is a way of reducing the risk of blood clots. In the market they have these big pumps at the end of the bed in hospitals.

“If you add together the deaths every year from breast cancer, road traffic accidents and AIDS, multiply it by two – that’s how many people die in hospital every year from a DVT. It’s the single largest cause of preventable death in the NHS.

“In 94% of cases it’s not diagnosed prior to death. It’s a massive killer, it’s over the whole of the developed and developing world. What they tried to do was reduce the risk of it with patients undergoing surgery – particularly after surgery. With surgery you’re immobilised for long periods of time, so you’re static and if your blood is static it clots. If you keep it moving it can’t clot. So, they try and keep it moving with pumps that squeeze the leg.”

That’s where the smaller, wearable Geko device comes in. In its appearance you’d be forgiven for thinking it was a wristwatch from afar. The plastic casing is made from polypropylene, and the device features printed circuit boards, electrodes, batteries, conductive gels and adhesives. Materials and parts are sourced in the UK, as well as the product’s assembly before being sold into the developing world.

“The gels used in this are now bespoke to this product. We started off with hydrogels you could get off the shelf, but they have certain issues and characteristics. We needed a hydrogel that could be used on people with poor skin conditions that give the right amount of conductivity of electricity but also was adhesive.

“It doesn’t go right round the leg, it rests on the skin, but it only needs to go over the nerve. The fact it looks like a wristwatch, we didn’t immediately decide to do that but when you look at what’s needed for it, that is the best shape.”

It isn’t just for the prevention of blood clots, as a pleasing side effect of the device has demonstrated a more rapid rate of wound healing by those who use the device.

Explaining why this is the case, Ross elaborates: “The benefit of the Geko device is we eliminate the surgical pain, they don’t come back and there’s huge cost savings. We found that by putting the device here we increase blood flow, venous return. This means that capillaries empty the blood which means that each squeeze of the heart hasn’t got the resistance to hold blood in the capillaries, which means you’ve got much more increase of blood flow in the skin where all of the capillaries are. You can get increased blood flow to the skin and you’ve got a wound that won’t heal there because of circulation. You put the blood flow back in, it heals. Wounds are healing with the device twice as fast.”

There’s also plans to further develop the device as more medical devices delve into the world of connected health, and the increasing nature of the electronic health records combined with the desire for immediate information about one’s health. The potential for connectivity is easy to spot from when it’s turned on.

“When you first put it on, it just looks like rapid flashing but it’s not, it’s sending signals in that telemetry of what the history of that device is.

“We’re at the stage now where we’re developing the next generation device that starts communicating with everything else around it. This device increases blood flow. For blood clot prevention in the hospital, it needs to be on all of the time. But for other times it doesn’t have to be on all of the time – so you need to know how long it needs to be on for.

“The next generation device will measure how much foot twitch you get so it can self-regulate. There’s a lot you can do with this.” 

You can find out more about the Geko device at the Med-Tech Innovation Expo on 29-30 September at NEC, Birmingham. Matthew Watts, head of product R&D at Sky Medical will be speaking about bringing the device to market on the HealthTech Stage on day one of the Expo.