Researchers at the University of Texas, have looked at data for treatment of sub-arachnoid haemorrhage (SAH) in the state during the 1990s. People with a stroke caused by bleeding into the brain do best in hospitals dealing with many such cases. In SAH, a blood vessel bursts within the blood supply surrounding the brain's exterior. It can cause brain damage, coma and death.
Data on nearly 10,000 patients admitted to 300 emergency departments was scanned, in terms of how many cases the departments saw a year. High volume hospitals were those seeing 20 to 50 cases, while low volume hospitals would see, typically, between zero and nine cases.
Mortality from SAH was 40 per cent in low volume hospitals, compared to 30 per cent in high volume hospitals. Despite this, few referrals are made to high volume departments. The findings on SAH mirror those seen for other complex medical conditions such as coronary bypass and carotid endarterectomy (a surgical procedure done on patients at risk of stroke caused by blood clotting).