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Abstract

Our aim was to study the frequency and reasons an emergent electroencephalogram (EmEEG) is ordered in the ICUs compared to the hospital ward, examine its usefulness and find predictive variables for its results.

We retrospectively identified all electroencephalograms ordered between December 1997 and March 2002 and performed within 1 hour. Tthe tests ordered from four ICUs were compared with those ordered from the Ward beds, and predictive models were developed for the results based on clinical variables. We also compared the EmEEGs ordered by the Neuro-ICU to those from the other Units.

The ICUs ordered 129 (49.4%) of all EmEEGs during the study period. The NICU ordered 32 tests. The most frequent reason for obtaining the test was to rule out status epilepticus (68.2%). The NICU ordered more frequently the test to exclude non-convulsive status than the other ICUs. Compared to non-ICU, ICU patients with head trauma or post cardiopulmonary arrest had more tests and patients with stroke fewer. Convulsive status epilepticus and generalized slowing were found more frequently in the ICUs, and normal EEG, interictal epileptiform activity or focal non-epileptic slowing were more frequent in the non-ICU cases. In at least 12.4% of ICU patients, the test was expected to lead to an anti-epileptic management change. Cardiopulmonary arrest and age were predictive of any epileptic activity on the EEG in ICU patients.

In conclusion, in our institution EmEEG is ordered by the ICUs in two thirds of the cases to exclude status epilepticus. Although status epilepticus is confirmed more frequently in the ICUs than on the Ward, the most frequent finding remains generalized slowing, which is found in half of the ICU-ordered EmEEGs. A conservative estimation is that EmEEG will lead to medication change in at least 1 out of 8 ICU patients. Cardioopulmonary arrest is predictive of epileptic activity and a prolonged EmEEG may also increase the yield.

Keywords

Cardiac Arrest Convulsive Status Epilepticus Electroencephalography Emergent

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References

Vespa

Nenov

Nuwer

. Continuous EEG monitoring in the intensive care unit: Early findings and clinical efficacy. J Clin Neurophysiol 1999, 16: 1–13.

Young

Jordan

Doig

. An assessment of nonconvulsive seizures in the intensive care unit using continuous EEG monitoring: An investigation of variables associated with mortality. Neurology 1996; 47: 83–89.

Jordan

. Continuous EEG monitoring in the neuroscience intensive care unit and emergency department. J Clin Neurophysiol 1999; 16: 14–39.

Hoefnagels

Padberg

Overweg

Roos

van Dijk

Kamphuisen

. Syncope or seizure? The diagnostic value of the EEG and hyperventilation test in transient loss of consciousness. J Neurol Neurosurg Psychiatry 1991; 54: 953–956.

Marsan

Zivin

. Factors related to the occurrence of typical paroxysmal abnormalities in the EEG records of epileptic patients. Epilepsia 1970; 11: 361–381.

Vespignani

Ducrocq

Schaff

. Indications for emergency EEG in disease, a brief loss of consciousness in generalized epileptic seizures in the adult, [in French]. Neurophysiol Clin 1997; 27: 390–397.

Gotman

Marciani

. Electroencephalographic spiking activity, drug levels, and seizure occurrence in epileptic patients. Ann Neurol 1985; 17: 597–603.

Gotman

Koffler

. Intenctal spiking increases after seizures but does not after decrease in medication. Electroencephalogr Clin Neurophysiol 1989; 72: 7–15.

van Donselaar

Schimsheimer

Geerts

Declerck

. Value of the electroencephalogram in adult patients with untreated idiopathic first seizures. Arch Neurol 1992; 49: 231–237.

10.

Varelas

Spanaki

Hacein-Bey

Hether

Terranova

. Emergent EEG: Indications and diagnostic yield. Neurology 2003; 61: 702–704.

11.

Bleck

Smith

Pierre-Louis

Jares

Murray

Hansen

. Neurologic complications of critical medical illnesses. Crit Care Med 1993; 21: 98–103.

12.

Wijdicks

Sharbrough

. New-onset seizures in critically ill patients. Neurology 1993; 43: 1042–1044.

13.

Vespa

Nuwer

Nenov

. Increased incidence and impact of nonconvulsive and convulsive seizures after traumatic brain injury as detected by continuous electroencephalographic monitoring. J Neurosurg 1999; 91: 750–760.

14.

Towne

Waterhouse

Boggs

. Prevalence of nonconvulsive status epilepticus in comatose patients Neurology 2000; 54: 340–345.

15.

Kaplan

. Nonconvulsive status epilepticus in the emergency room. Epilepsia 1996; 37: 643–650.

16.

DeLorenzo

Hauser

Towne

. A prospective, population-based epidemiologic study of status epilepticus in Richmond, Virginia. Neurology 1996; 46: 1029–1035.

17.

Towne

Pellock

DeLorenzo

. Determinants of mortality in status epilepticus. Epilepsia 1994; 35: 27–34.

18.

Fountain

. Status epilepticus: Risk factors and complications. Epilepsia 2000; 41: S23–30.

19.

Bogousslavsky

Martin

Regli

Despland

Bolyn

. Persistent worsening of stroke sequelae after delayed seizures. Arch Neurol 1992; 49: 385–388.

20.

Litt

Wityk

Hertz

. Nonconvulsive status epilepticus in the critically ill elderly. Epilepsia 1998; 39: 1194–1202.

21.

Krumholz

Sung

Fisher

Barry

Bergey

Grattan

. Complex partial status epilepticus accompanied by serious morbidity and mortality. Neurology 1995; 45: 1499–1504

22.

DeLorenzo

Waterhouse

Towne

. Persistent nonconvulsive status epilepticus after the control of convulsive status epilepticus. Epilepsia 1998; 39: 833–840.

23.

Kaplan

. Assessing the outcomes in patients with nonconvulsive status epilepticus: Nonconvulsive status epilepticus is underdiagnosed, potentially overtreated, and confounded by comorbidity. J Clin Neurophysiol 1999; 16: 341–353.

24.

Quigg

Shneker

Domer

. Current practice in administration and clinical criteria of emergent EEG. J Clin Neurophysiol 2001; 18: 162–165.

25.

Khan

Yerremsetty

Lindstrom

McGill

. Emergency EEG and factors associated with nonconvulsive status epilepticus. J Natl Med Assoc 2001; 93: 359–362.

26.

Privitera

Hoffman

Moore

Jester

. EEG detection of nontonic-clonic status epilepticus in patients with altered consciousness. Epilepsy Res 1994; 18: 155–166.

27.

Briggs

Felberg

Malkoff

Bratina

Grotta

. Should mild or moderate stroke patients be admitted to an intensive care unit? Stroke 2001; 32: 871–876.

28.

Varelas

Mirski

. Seizures in the adult intensive care unit. J Neurosurg Anesthesiol 2001; 13: 163–175.

29.

Treatment of convulsive status epilepticus. Recommendations of the Epilepsy Foundation of America's Working Group on Status Epilepticus. JAMA 1993; 270: 854–859.

30.

Snyder

Hauser

Loewenson

Leppik

Ramirez-Lassepas

Gumnit

. Neurologic prognosis after cardiopulmonary arrest: III. Seizure activity. Neurology 1980; 30: 1292–1297.

31.

Krumholz

Stern

Weiss

. Outcome from coma after cardiopulmonary resuscitation: Relation to seizures and myoclonus. Neurology 1988; 38: 401–405.

32.

Thomas

. Status epilepticus: Indications for emergency EEG. [in French]. Neurophysiol Clin 1997; 27: 398–405.

33.

Walsh

Delgado-Escueta

. Status epilepticus. Neurol Clin 1993; 11: 835–856.

34.

Privitera

Strawsburg

. Electroencephalographic monitoring in the emergency department. Emerg Med Clin North Am 1994; 12: 1089–1100.

35.

Ramsay

. Treatment of status epilepticus. Epilepsia 1993; 34: S71–81.

36.

Bleck

. Advances in the management of refractory status epilepticus. Crit Care Med 1993; 21: 955–957.

37.

Treiman

Walton

Kendrick

. A progressive sequence of electroencephalographic changes during generalized convulsive status epilepticus. Epilepsy Res 1990; 5: 49–60.

Emergent Electroencephalogram in the Intensive Care Unit: Indications and Diagnostic Yield

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