Approach To Newonset Seizures In The Hospital

Initial diagnostic evaluation and treatment must often occur simultaneously, at least until the patient has been stabilized and there is time for more extensive consideration of the clinical situation. Caring for acute seizures in the hospital begins with basic life support measures, including ensuring the patient has a patent airway, is breathing adequately and has intact circulation. While vital signs, electrocardiography and pulse oximetry monitoring are being

Karine J. Abou Khaled, MD, NYU Comprehensive Epilepsy Center, New York, USA. Currently at Hotel-Dieu de France Hospital, Department of Neurology, Saint Joseph University, Beirut, Lebanon

Lawrence J. Hirsch, MD, Associate Clinical Professor of Neurology, NYU Comprehensive Epilepsy Center; Department of Neurology, Columbia University, New York, New York, USA

implemented, care-givers should ensure the patient is in a safe position to prevent injury and/ or aspiration. Part of assessment of circulation is obtaining intravenous access and obtaining blood for laboratory studies. In addition to bedside glucose testing, and electrolytes including calcium, laboratory tests should be chosen based on what is known about the patient's other medical conditions, including tests of renal and hepatic function. Part of the initial assessment includes a focused review of the patient's history, including recent neurological and systemic complaints, medications (especially those recently introduced), and drug and alcohol use. A proposed timetable and treatment protocol for acute seizures in the hospitalized patient are outlined in Table 12.1. Treatment should be first directed towards all potentially correctable underlying causes, as delineated in Tables 12.2 and 12.3. Most seizures cease spontaneously within 5 minutes, requiring no immediate intervention. If a seizure is prolonged (longer than 5 minutes), treatment with an intravenous benzodiazepine such as lorazepam is generally indicated. Treatment of status epilepticus is discussed in detail in Chapter 14.

Once the patient has been stabilized and the initial evaluation is complete, more extensive evaluation includes a focused physical examination to identify focal neurological deficits or other clues to the underlying aetiology of the seizure. Following this, urgent brain imaging is usually warranted. Non-contrast computerized tomography (CT) imaging of the head, which can be obtained rapidly, is useful for identifying acute intracranial haemorrhage and can identify subacute or chronic cerebral infarcts, mass lesions and hydrocephalus. Magnetic resonance imaging (MRI) is superior in the less-emergent setting for characterizing the huge variety of lesions that may cause seizures, including cerebral infarcts, oedema, tumours or abscesses or other infections. Specific MRI sequences are important for certain diagnoses

Table 12.1 Evaluation and initial treatment of acute seizures in adults

Time (min)

Action

0-5

Diagnose; give oxygen; stabilize airway, breathing and circulation; obtain intravenous access; begin ECG monitoring; draw blood for electrolytes, BUN test, creatinine, glucose, magnesium, calcium, phosphate, complete blood count, liver enzymes, anti-epileptic drug levels, arterial blood gas test, troponin; toxicology screen (urine and blood)

6-10

If still seizing or not back to baseline mental status and adequate glucose not documented, give thiamine 100 mg i.v. and 50 ml of D50 i.v. If still seizure activity: Lorazepam 4 mg i.v. over 2 min; if still seizing, repeat x 1 in 5 mins

If no rapid i.v. access give diazepam 20 mg PR or midazolam 10 mg intranasally, buccally or i.m.*

10-20

If seizures persist, or patient estimated to be at high risk for recurrence or high risk for seizure-related adverse secondary effects, begin fosphenytoin 20 mg/kg i.v. at 150 mg/min, with blood pressure and ECG monitoring. For ongoing seizures (i.e. status epilepticus), this step can be skipped initially, especially if proceeding to midazolam or propofol infusion, or performed simultaneously with the next step; if done simultaneously, administration rate can be slowed. Valproic acid i.v. 25-40 mg/kg is a reasonable alternative in specific situations (e.g. hypotensive). i.v. Levetiracetam 1500-4000 mg i.v. may be a reasonable option in those with contraindications to phenytoin and valproate Begin electroencephalography monitoring if patient does not rapidly awaken to rule out non-convulsive seizures

*The i.v. solution of diazepam can be given rectally if Diastat is not available; the i.v. solution of midazolam can be given by any

of these routes.

BUN, blood urea nitrogen; ECG, electrocardiography; i.m., intramuscular; i.v., intravenous.

Table 12.2 Common aetiologies of seizures in hospitalized patients

History of epilepsy

Medication withdrawal or non-compliance

Other

Acute neurological insult

Cerebrovascular disease: infarct, haemorrhage, vasculitis

Intracranial haemorrhage: subarachnoid, subdural, intracerebral, other

Infection: meningitis, encephalitis, brain abscess

Head trauma

Anoxia

Brain tumours

Demyelinating disorders

Acute systemic insult

Electrolyte imbalance: hyponatraemia, hypocalcaemia,

hypomagnesaemia, hypophosphataemia (especially in alcoholics)

Hypoglycaemia, and hyperglycaemia with hyperosmolar state; both

can cause focal seizures as well

Vitamin deficiency: pyridoxine

Illicit drug use

Toxins

Hypertensive encephalopathy (also known as reversible posterior

leukoencephalopathy syndrome [RPLS] or posterior reversible

encephalopathy syndrome [PRES])

Hypotension from shock or secondary to syncope

Organ failure: uraemia, hepatic failure, cardiac failure

Multi-system illness such as systemic lupus erythematosus

Medications: side-effects, toxicity, withdrawal (see Table 12.3)

Alcohol related

Systemic infection/sepsis

Eclampsia

Table 12.3 Medications that can lower the seizure threshold [74, 75]

Antidepressants, especially bupropion and maprotiline Neuroleptics, especially clozapine, but also phenothiazines Lithium Baclofen

Phenytoin at supratherapeutic levels (including very high free levels) Theophylline

Analgesics: meperidine, fentanyl and tramadol Opioid withdrawal

Antibiotics: beta-lactams (imipenem, cefazolin), quinolones, isoniazid (treat with B6 for seizures related to isoniazid), metronidazole Anti-arrhythmic medications: mexiletine, lidocaine, digoxin Radiographic contrast agents

Immunomodulators: cyclosporine, tacrolimus, interferons Chemotherapeutic agents: alkylating agents such as chlorambucil and busulfan

- for example, diffusion-weighted imaging (DWI) is best for identifying acute ischaemia. Fluid-attenuated inversion recovery (FLAIR) sequences are used to detect inflammatory changes or oedema. In the reversible posterior leukoencephalopathy syndrome ([RPLS], a cause of seizures associated with hypertension, particularly in transplant patients on certain immunosuppressant medications) FLAIR images may show bilateral hyperintensities in the subcortical and cortical parieto-occipital regions, and DWI images will show increased diffusion, corresponding to vasogenic oedema rather than ischaemia [2, 3].

Additional diagnostic testing should be guided by the patient's specific clinical situation. Lumbar puncture may be needed in the setting of headache, meningismus, rash or other signs of infection, immunosuppression or recent neurosurgery. Following repetitive seizures or status epilepticus, the cerebrospinal fluid (CSF) white cell count may be mildly and transiently elevated, and CSF protein might also be mildly elevated secondary to blood-brain barrier breakdown [4].

A large number of critically ill patients have non-convulsive seizures, unrecognized by care-givers, and diagnosed only by electroencephalogram (EEG) monitoring [5, 6]; at our centre, 101 of 110 intensive care unit (ICU) patients who had seizures recorded while undergoing continuous EEG monitoring had purely non-convulsive seizures that would have been missed without EEG [5]. Risk factors for non-convulsive seizures or NCSE include coma, age < 18, prior convulsive seizures, acute or remote risk factors for epilepsy, oculomotor abnormalities (such as nystagmus, eye deviation and even hippus), and EEG findings of periodic lateralized epileptiform discharges (PLEDs) or burst-suppression [5, 7]. In our series of 97 patients in coma who had continuous EEG ordered, 56% had non-convulsive seizures.

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Do Not Panic

Do Not Panic

This guide Don't Panic has tips and additional information on what you should do when you are experiencing an anxiety or panic attack. With so much going on in the world today with taking care of your family, working full time, dealing with office politics and other things, you could experience a serious meltdown. All of these things could at one point cause you to stress out and snap.

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