eMedicine Specialties > Emergency Medicine > Neurology
Status Epilepticus: Differential Diagnoses & Workup
Updated: Aug 24, 2009
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
Differential Diagnoses
Other Problems to Be Considered
Catatonia
Coma
Psychogenic nonepileptic seizures (PNES) (pseudoseizures)
Repetitive extensor or flexor posturing
Stimulant intoxication
Workup
Laboratory Studies
- Clinical information should guide the ordering of laboratory tests.
- Several studies have shown the low yield of multiple laboratory tests in the evaluation of patients presenting with a single seizure.6
- However, status epilepticus should prompt a search for the etiology of status epilepticus or potentially reversible conditions.
- Perform rapid glucose determination shortly after the patient's arrival.
- Obtain additional electrolyte levels, particularly sodium.
- Calcium level abnormalities are an infrequent cause of status epilepticus, but serum calcium level should be obtained in certain patients, notably those with a history of malignancy.
- Toxicologic testing initially should be directed toward determining anticonvulsant levels in a patient with a history of seizures. Theophylline toxicity is a notable exception, since detection of toxic levels would alter therapy.
- Arterial blood gas (ABG) determination following an episode of generalized seizures reveals a metabolic acidosis.
- ABG level determination may be useful to monitor oxygenation and effective ventilation and to discover any unexpected acid-base abnormalities. Metabolic acidosis should correct rapidly following seizure cessation as the lactate generated by vigorous muscle contractions is metabolized.
- Profound metabolic acidosis and continuing seizures might raise the possibility of isoniazid poisoning (see Toxicity, Isoniazid).
Imaging Studies
- For patients with new-onset seizures or status epilepticus, noncontrast CT in the ED is the procedure of choice because of the availability and the utility of the test in detecting acute hemorrhage. Consider neuroimaging if a question exists about the etiology of the status epilepticus or if the episode is difficult to control. Imaging is often deferred if the patient is known to have epilepsy and the seizure pattern is not unusual for the individual.
- MRI offers better anatomic detail than CT scan, but the longer test time, difficulties with patient management, and uneven availability all weigh against use of MRI by the emergency physician at this time.
- Chest radiography may be used to assess for aspiration or endotracheal tube positioning. If clinically indicated, other plain radiographs may be useful to assess fractures or dislocations.
Other Tests
- Electroencephalogram
- EEG is not routinely available in the ED.
- Because of the possibility of subtle GCSE, an EEG should be strongly considered if the patient is not starting to awaken within 20-30 minutes after seizure cessation.
- EEG availability varies greatly at different institutions.
- Normally, EEG is obtained through neurologic consultation.
Procedures
- Consider a lumbar puncture (LP) if CNS infection is in the differential diagnosis. Initiate antibiotic therapy if CNS or systemic infection is strongly suspected.
More on Status Epilepticus |
| Overview: Status Epilepticus |
 Differential Diagnoses & Workup: Status Epilepticus |
| Treatment & Medication: Status Epilepticus |
| Follow-up: Status Epilepticus |
| References |
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References
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DeLorenzo RJ, Hauser WA, Towne AR, Boggs JG, Pellock JM, Penberthy L, et al. A prospective, population-based epidemiologic study of status epilepticus in Richmond, Virginia. Neurology. Apr 1996;46(4):1029-35. [Medline].
Lowenstein DH, Alldredge BK. Status epilepticus. N Engl J Med. Apr 2 1998;338(14):970-6. [Medline].
Leis AA, Ross MA, Summers AK. Psychogenic seizures: ictal characteristics and diagnostic pitfalls. Neurology. Jan 1992;42(1):95-9. [Medline].
Jagoda A, Richey-Klein V, Riggio S. Psychogenic status epilepticus. J Emerg Med. Jan-Feb 1995;13(1):31-5. [Medline].
[Guideline] ACEP Clinical Policies Committee; Clinical Policies Subcommittee on Seizures. Clinical policy: Critical issues in the evaluation and management of adult patients presenting to the emergency department with seizures. Ann Emerg Med. May 2004;43(5):605-25. [Medline].
Rossetti AO, Oddo M, Liaudet L, Kaplan PW. Predictors of awakening from postanoxic status epilepticus after therapeutic hypothermia. Neurology. Feb 24 2009;72(8):744-9. [Medline].
Treiman DM, Meyers PD, Walton NY, Collins JF, Colling C, Rowan AJ, et al. A comparison of four treatments for generalized convulsive status epilepticus. Veterans Affairs Status Epilepticus Cooperative Study Group. N Engl J Med. Sep 17 1998;339(12):792-8. [Medline].
Aggarwal P, Wali JP. Lidocaine in refractory status epilepticus: a forgotten drug in the emergency department. Am J Emerg Med. May 1993;11(3):243-4. [Medline].
[Guideline] Epilepsy Foundation of America's Working Group. Treatment of convulsive status epilepticus. Recommendations of the Epilepsy Foundation of America's Working Group on Status Epilepticus. JAMA. Aug 18 1993;270(7):854-9. [Medline].
Fountain NB, Lothman EW. Pathophysiology of status epilepticus. J Clin Neurophysiol. Jul 1995;12(4):326-42. [Medline].
Huff JS. Seizures and status epilepticus in adults: Part II. Emerg Med Rep. 2007;28(24):281-88.
Kumar A, Bleck TP. Intravenous midazolam for the treatment of refractory status epilepticus. Crit Care Med. Apr 1992;20(4):483-8. [Medline].
Limdi NA, Shimpi AV, Faught E, Gomez CR, Burneo JG. Efficacy of rapid IV administration of valproic acid for status epilepticus. Neurology. Jan 25 2005;64(2):353-5. [Medline].
Lowenstein DH, Alldredge BK. Status epilepticus at an urban public hospital in the 1980s. Neurology. Mar 1993;43(3 Pt 1):483-8. [Medline].
Prasad A, Worrall BB, Bertram EH, Bleck TP. Propofol and midazolam in the treatment of refractory status epilepticus. Epilepsia. Mar 2001;42(3):380-6. [Medline].
Privitera MD, Strawsburg RH. Electroencephalographic monitoring in the emergency department. Emerg Med Clin North Am. Nov 1994;12(4):1089-100. [Medline].
Wheless JW, Vazquez BR, Kanner AM, Ramsay RE, Morton L, Pellock JM. Rapid infusion with valproate sodium is well tolerated in patients with epilepsy. Neurology. Oct 26 2004;63(8):1507-8. [Medline].
Further Reading
Keywords
status epilepticus, generalized convulsive status epilepticus, GCSE, seizure, subtle status epilepticus, nonconvulsive status epilepticus, epilepsy, seizure disorder, tonic-clonic activity, persistent tonic seizure, idiopathic seizure disorder, stroke, hypoxic injury, tumor, subarachnoid hemorrhage, trauma, toxicologic effects, electrolyte abnormality, hyponatremia, hypernatremia, hypercalcemia, hepatic encephalopathy, meningitis, brain abscess, encephalitis, metabolic acidosis, isoniazid toxicity, anticonvulsant irregularity
