Outcomes in specialist units using protocols may not be better

EDITOR—Mortality and morbidity from head injury seem to have fallen, presumably with use of organised trauma care systems and adequate critical care.1 In his editorial on treating head injuries Wasserberg said that evidence now shows an overall improvement in the outcome of head injury from treatment in a specialist unit that uses protocol driven treatment.2

Skull fracture

Credit: SCIENCE PHOTO LIBRARY

This statement is not based on a randomised controlled trial but a retrospective survey showing that in the whole referral population the tendency to increased favourable outcome after institution of protocol driven treatment did not reach significance and the overall mortality did not change significantly.3 Only patients with severe head injury showed an increase in favourable outcome, without a difference in mortality. Wasserberg's statement therefore seems unsubstantiated.

All protocol driven treatments are based on successive introduction of hyperventilation, drainage of cerebrospinal fluid, infusion of mannitol, hypothermia, barbiturates, and (rarely) decompressive craniotomy—all treatments lowering intracranial pressure. Two studies cited by Raj and Narayan (by Roberts et al, reference 11, and Dickinson et al, reference 5) concluded on the basis of randomised controlled trials that it was impossible to refute either a moderate increase or a moderate decrease in the risk of death or disability from the use of hyperventilation, drainage of cerebrospinal fluid, mannitol, barbiturates, or corticosteroids.1

Wasserberg quotes a Cochrane review, concluding that no evidence exists that hypothermia is beneficial in head injury, forgetting that a …