The Deleterious Effects of Intraoperative Hypotension on Outcome in Patients with Severe Head Injuries.
Intraoperative hypotension was defined as a systolic blood pressure of 90 mmHg or less. The
mortality rate for patients with hypotension was 82% and 25% in the normotensive group. Only
32% of hypotensive patients received pharmacologic blood pressure support. Prehospital hypoten
sion doubles the mortality for patients with severe head injuries (GCS </= 8). Secondary brain injury
is produced by hypoxia and hypotension and is present in approximately 30% of patients with head
injuries. Despite rapid transport and aggressive resuscitation, Shackford found that 66% of patients
who died of head injury had evidence of secondary ischemic injury. Maintenance of adequate cere
bral perfusion pressure should be the goal of resuscitation in the prehospital and the in-hospital
phase of care in patients with head injuries. Hypotension in lesser head injuries may convert revers
ible neurological deficits into permanent deficits. These authors suggest more aggressive use of
pharmacologic agents to maintain adequate cerebral perfusion pressures if volume resuscitation fails
to meet this goal. Anesthesiologists should avoid agents that provoke hypo-tension in these patients.
J. Trauma 33:403, Sept. 92.