approximately 90 mL/100 g/min and then gradually declines to adult levels by
the mid to late teens. However, cerebral auto-regulation is often disrupted after
severe TBI thereby making CBF difficult to interpret and utilize consistently in
the management of TBI. Further details regarding monitoring can be found in
chapter detailing ICU monitoring.
In the past, treatments were directed towards decreasing ICP. Both
fluid restriction and hyperventilation were key strategies. However, current
methods include optimizing the CPP and decreasing ICP. Pediatric TBI
guidelines involve maintaining CPP between 40 and 65 mm Hg. Most
guidelines recommend a minimum CPP of 40 mmHG. ICP elevations above 20
mmHg are not tolerated well by the injured brain and are likely to have poor
morbidity and mortality. Sustained increased ICP may result in decreased
cerebral perfusion and lead to subsequent herniation. Therefore patients with
ICP greater than 20 mmHg should undergo treatment for ICP. Intraventricular
devices effectively allow drainage of CSF in order to decrease ICP.
IV. Intensive Care Management
The patient should be positioned with the head of the bed elevated to
15 - 30 degrees. This position facilitates venous drainage from the head.
Ventilation should maintain a PaCO2 of 35-40 mmHg as hypercapnia may
cause significant increases in cerebral blood volume and flow. Hyperventilation
can temporarily assist in reduction of ICP by causing cerebral vasoconstriction
and thereby reducing cerebral blood flow. However, hyperventilation is