The prehospital phase of head injury, also called the critical phase, consi
sts of trauma-induced apnea and stress catecholamine release. This immediat
e period after head injury remains poorly summarized in the literature and
essentially ignored with respect to treatment. A MEDLINE search of the lite
rature on apneustic response and catecholamine surge after head injury and
a review of literature from my acquired references revealed 116 references
(from more than 600) that were pertinent, Apnea induced by head injury prod
uces hypoxia, hypercarbia, and subsequent cardiac failure and hypotension,
which, along with substantially elevated catecholamine values, promote seco
ndary mechanisms of organ injury. Treatment for this immediate period after
head injury requires a rapid response to the scene of trauma and developme
nt of treatment options that can be instituted at the scene of injury.