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786 PART 6: Neurologic Disorders

One study of 86 children presenting with seizure found that those who
received lorazepam had a higher incidence of termination of seizure • Towne AR, Waterhouse EJ, Boggs JG, et al. Prevalence of non-
convulsive status epilepticus in comatose patients. Neurology.
activity and less frequent respiratory depression than those treated with
diazepam. 108 2000;54:340-345.
Midazolam administered by continuous infusion appears effective • Waterhouse EJ, Vaughan JK, Barnes TY, et al. Synergistic effect of
in RSE in children. 97,109,110 Although all eight patients in one study were status epilepticus and ischemic brain injury on mortality. Epilepsy
mechanically ventilated, none demonstrated cardiovascular instability Res. 1998;29:175-183.
despite midazolam doses resulting in burst suppression. 108
As with adults, rapid control of SE in children achieved with benzodi-
azepines should be followed by administration of a longer-acting agent REFERENCES
such as phenytoin (20 mg/kg IV), fosphenytoin (20 mg PE/kg IV), or phe-
nobarbital (10-20 mg/kg IV). The rate of conversion of fosphenytoin Complete references available online at www.mhprofessional.com/hall
111
to phenytoin is probably the same in children as in adults. Intramuscular
injection of fosphenytoin may be particularly advantageous for preven-
tion of recurrent seizures in children without IV access. The use of IV
fosphenytoin over IV phenytoin is prudent in infants and neonates, CHAPTER Intracranial Pressure:
whose small limbs are at especially high risk of extensive necrosis and
Similarly to the treatment of seizures and SE in adults, there is 86
amputation in the event of a phenytoin extravasation. Monitoring and
growing evidence to support the use of levetiracetam. In the neonatal Management
period, intravenous levetiracetam has been found useful and safe as Geraldine Siena L. Mariano
monotherapy or as an adjunct in acute seizure management. When
112
administered within half an hour of seizure onset in children at a dose of Matthew E. Fink
29.4 ± 13.5 mg/kg, 89% of patients were seizure free at 1 hour. When Caitlin Hoffman
113
given with a bolus dose of 25 to 50 mg/kg followed by maintenance as Axel Rosengart
adjunct or monotherapy for status epilepticus or exacerbation of seizure
disorder, response rates were as well favorable. 114
Intravenous valproate appears to be safe and effective in children. KEY POINTS
115
Several retrospective and prospective series have reported seizure ter- • To gain an understanding of the mechanisms and anticipatory man-
mination after infusion of valproate in loading doses between 25 and agement of brain tissue displacement (herniation) and intracranial
30 mg/kg, with response rates between 65% and 100% and without hypertension.
occurrence of serious adverse events. 115-117
• To understand available brain monitoring devices in measuring
ICP and to appreciate their role in guiding early interventions to
avoid secondary brain injury as hesitation to monitor intracranial
KEY REFERENCES pressure dynamics, and to aggressively pursue ICP management
likely accounts for the vast majority of secondary brain injury in
• Bleck TP. Status epilepticus and the use of continuous electroen- patients with reduced level of consciousness.
cephalographic monitoring in the intensive care unit. Continuum • To foster an individualized patient approach in addressing abnor-
Neurology. 2012;18:560-578. mal ICP and flow dynamics within the practice of neurocritical
• Brophy GM, Bell R, Claasen J, et al. Guidelines for the evaluation care. Understanding the indications for brain monitoring via
and management of status epilepticus. Neurocritical Care. 2012;16. real-time parenchymal blood flow, oxygen tension, and chemistry
• Fountain NB, Lothman EW. Pathophysiology of status epilepticus. surveillance, as well as mastering the current recommendations
J Clin Neurophysiol. 1995;12:326-342. in aggressive management approaches toward elevated ICP such
• Oddo M, Carrera E, Claassen J, Mayer SA, Hirsch LJ. Continuous as induced hypothermia, suppression of abnormal electrical dis-
electroencephalography in the medical intensive care unit. Crit charges, and early surgical decompression are necessary tools for
Care Med. 2009;37:2051-2056. the neurocritical care clinician.
• Sharma V, Katznelson R, Jerath A, et al. The association between
tranexamic acid and convulsive seizures after cardiac sur-
gery: a multivariate analysis in 11 529 patients. Anaesthesia. CONSIDERATION OF CEREBRAL PRESSURE
2014;69(2):124-130. AND FLOW DYNAMICS
• Shneker BF, Fountain NB. Assessment of acute morbidity
and mortality in nonconvulsive status epilepticus. Neurology. ■ COMPARTMENTS AND MONRO-KELLIE DOCTRINE
2003;61:1066-1073. In adults, the cranial vault represents a closed, noncompliant structure.
• Shorvon S. Super-refractory status epilepticus: an approach to Two important exceptions exist in which intracranial compliance is
therapy in this difficult clinical situation. Epilepsia. 2011;52(suppl increased. These are at the foramen magnum and craniectomy sites.
8):53-56. Craniectomy refers to surgical bone removal to treat refractory intra-
• Silbergleit R, Durkalski V, Lowenstein D, et al. Intramuscular cranial hypertension or as a by-product of neurosurgical decompression
versus intravenous therapy for prehospital status epilepticus. for an alternate indication. This removal of bone leaves a palpable, soft,
N Engl J Med. 2012;366:591-600. cranial defect covered only by dura, galea, and skin. The brain is distin-
• Swisher CB, Doreswamy M, Gingrich KJ, Vredenburgh JJ, Kolls guished from other organs by the unique challenge of monitoring brain
BJ. Phenytoin, levetiracetam, and pregabalin in the acute manage- function and intracranial dynamics in a structure enclosed by a bony
ment of refractory status epilepticus in patients with brain tumors. vault. The noncompliant surrounding bone of the calvarium does not
Neurocrit Care. 2012;16:109-113. allow for significant volume change of the brain or adjustment of intra-
cranial pressure (ICP) (Fig. 86-1A). As a result, the pressure within the

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