Beneficial effects of adrenergic blockade in patients with subarachnoid haemorrhage

A total of 148 patients presenting within 48 hours of subarachnoid haemorrhage were assigned at random to receive standard management only or standard management and treatment with the adrenergic-blocking agents propranolol and phentolamine (or propranolol alone) for three weeks. One hundred and thirty-four patients completed the study. Assessment at four weeks showed a strong trend for less neurological deficit in the treated group, almost statistically significant (p=0.053) in the women. During the first month the treated group suffered fewer episodes of clinical deterioration consistent with cerebral arterial spasm: thus more treated patients underwent operation and those who did had a better outcome (p=0.030). At one year fewer were dead or disabled (unable to work) in the treated group; a significant difference for women (p=0.030). Possible mechanisms for these actions may include a reduction in pulmonary oedema, prevention of myocardial infarcts, a reduction in plasma renin activity, nd a reduction in cerebral oxygen requirements. It is concluded that early adrenergic blockade benefits patients (particularly women) with subarachnoid haemorrhage for up to one year in terms of lesser neurological deficit. Beta-blocker rather than alpha-blockade appears to be the useful component. A randomised, blind extension of the present study using long-acting propranolol and placebo has shown a significant (p=0.026) decrease in deaths and significantly (p=0.003) fewer poor results in the treatment group.