Neurocritical Care

Burst suppression on continuous EEG (target usually is 2–5 bursts/minute) is a surrogate end point

for need of additional pentobarbital doses.

A bolus dose is required concomitantly with an infusion titration because of its long half-life

(24–48 hours) and rapid redistribution.

Monitoring

ICP

EEG and burst occurrence per minute

Serum concentrations do not correlate well with ICP response and should not be used to titrate

infusion. May be useful when therapy has been discontinued as part of brain death examination (to

rule out continued intoxication from pentobarbital)

and osmolality should be monitored during prolonged treatment.

Adverse effects

Hypotension as the result of several different causes

Propylene glycol diluent

ii.

Direct vasodilator

iii.

Reduction in sympathetic tone because of metabolic suppression

iv.

Cardiac depressant (particularly with high doses and duration greater than 96 hours)

Bradycardia

Decreased GI motility and ileus

Difficulty with enteral nutrition

ii.

Caloric needs are usually around 80%–90% of basal energy needs, so a lower flow rate for

enteral nutrition is permissible.

iii.

Ideally, would use an elemental or semi-elemental nutrition product because stooling is rare

on pentobarbital infusion

Immunosuppression

Withdrawal seizures may occur.

Metabolic acidosis due to propylene glycol toxicity

Patient Case

his brain reveals a large right temporal subdural hematoma, an overlying skull fracture, and a left temporal

contusion. His post-resuscitation GCS is E1-M4-V1T. An ICP monitor is placed with an opening pressure

of 32 mm Hg, and CPP is 53 mm Hg. Serum laboratory values include Na 139 mEq/L, K 3.6 mEq/L, BUN

42 mg/dL, SCr 2.4 mg/dL, glucose 178 mg/dL, WBC 14.8 × 103 cells/mm3, pH 7.46, and Pco2 34 mm Hg.

Which is the best initial therapy for this patient’s elevated ICP?

these are “living guidelines” that will be updated continuously. Unfortunately, the newest guidelines reflect

only recommendations with high levels of evidence. Therefore, the 2007 guidelines may be needed to

review practical recommendations (based on all levels of evidence) for complications in patients with a TBI.