Neurocritical Care
Elevated ICP decreases tissue perfusion and tissue oxygenation and worsens neurologic outcome.
(80%). Each therapy targeted at decreasing ICP acts on one or more of these components.
Most practitioners use a stepwise approach to treating elevated ICP, including the following interventions:
Head-of-bed elevation (30–45 degrees): Optimizes venous return from the brain, reducing venous
pooling
Early treatment of fever (greater than or equal to 37.8°C) to maintain normothermia.
Osmotherapy (mannitol or hypertonic saline)
| d. | Acute hyperventilation: Reduction in Pco2 to around 32 mm Hg causes a compensatory |
|---|
vasoconstriction, which reduces cerebral blood volume (chronic hyperventilation should be avoided
because of complications such as stroke).
Drainage of CSF by a ventriculostomy
Sedation with or without neuromuscular blockade (avoid benzodiazepines, when possible)
Maintenance of CPP at 60–70 mm Hg
Surgical decompression or hemicraniectomy (depending on the clinical scenario)
Pharmacologic coma (pentobarbital)
Hypothermia (33°C–36°C) – Clinicians should consider the risk-benefit of moderate hypothermia
versus targeted temperature management for control of ICP.
Recommendations are to treat sustained (for greater than 5 minutes) ICP greater than 22 mm Hg as
measured by external ventricular drain, intraparenchymal catheter, or bolt (Neurosurgery 2017;80:6-
15). If subarachnoid hemorrhage, symptom-based dosing over ICP targets is suggested (Neurocrit Care
2020;32;647-66).
CPP ideally within 60–70 mm Hg
Targeting CPP greater than 80 mm Hg routinely is also associated with an increased incidence of
acute respiratory distress syndrome and mortality in patients with a TBI; thus, patients must be
Osmotherapy
Mannitol
Hypertonic Saline
Mechanism of action
Acute increase in cerebral blood flow
results in cerebral vasoconstriction
(because of autoregulation), leading to
decreased cerebral blood volume
Increase in serum osmolality creates
osmotic gradient to pull extracellular
fluid from brain
Osmotic diuretic
Acute increase in cerebral blood flow
results in cerebral vasoconstriction
(because of autoregulation), leading to
decreased cerebral blood volume
Increase in serum osmolality creates
osmotic gradient to pull extracellular
fluid from brain