That’s dynamite

‘Explosive’ patch could reduce effects of stroke

An explosive once favoured by safecrackers may help improve the outcome of patients who’ve had a stroke.

During a stroke, blood flow to the brain is dramatically reduced, which can quickly damage the brain; this can result in disability or can be fatal. one in six people will have a stroke at some point, with 32,000 stroke-related deaths in the UK every year.

now a trial is under way to see if a skin patch containing nitroglycerine can improve blood flow, and, in so doing, limit the damage and long-term effects.

The patch will be applied by paramedics while patients are in an ambulance on the way to hospital, within three hours of them having a suspected stroke.

As well as being used as an explosive, nitroglycerine is also used to treat people with angina — chest pain related to narrowed arteries to the heart. This is because it is converted by the body into nitric oxide, a compound that relaxes blood vessels, reducing blood pressure and improving blood flow.

The new patch works on the same principles.

There are two main types of stroke: the most common — accounting for 85 per cent of cases — is an ischaemic stroke, where the blood flow is blocked by a clot in the blood vessels supplying the brain; a haemorrhagic stroke occurs when a weakened blood vessel supplying the brain bursts, causing bleeding.

While ‘clot-busting’ drugs have helped improve outcomes for people who’ve had an ischaemic stroke, with haemorrhagic stroke the treatment focuses on controlling the bleeding and reducing the pressure caused by this, as well as drugs to help lower blood pressure. However, often brain tissue is irreversibly damaged before treatment is administered.

it’s hoped that the new patch could help. A previous study, involving 312 patients who were given a similar nitroglycerine patch but within six hours of the stroke occurring, found it reduced the risk of severe disability and death as well as reducing blood pressure, reported the journal stroke Research and Treatment in 2016.

in the new trial, being overseen by the University of Amsterdam, half of the 1,400 participants will get the patch, while the remainder will have the usual care administered to stroke patients.

After 90 days, the level of disability in the two groups of patients, will be compared.

Commenting on the new patch, Dr Yaqoob Bhat, clinical director in stroke medicine at Aneurin Bevan University Health Board, said: ‘This is an important trial to assess the effect of early blood pressure reduction on the outcome of stroke patients.

‘The results will be interesting to see.’