Professor Yu Cheuk-man, head of Prince of Wales Hospital's Division of Cardiology, says the first three minutes after the heart stops beating is the critical period. Most people who die of sudden death fail to get prompt medical support. "If resuscitation and electrical shock are administered to the patient in a timely manner, there's a 70 per cent survival rate. The survival rate drops by 10 per cent for every minute that passes," says Yu.
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