Cardiac arrest: adrenaline may increase severe brain damage

The results of a UK study are challenging the widespread practice of having paramedics give adrenaline at the scene of a cardiac arrest.

Adrenaline helped an extra 1% survive by making it easier to jump-start the heart, a study has found, but it almost doubled the risk of severe brain damage for survivors, possibly because it closed off small but vital blood vessels in the brain.

"It can restart the heart but it's no good for the brain," said chief author Dr Gavin Perkins of the University of Warwick Medical School.

"When we interviewed over 300 patients before the