Seizures & Status Epilepticus Management

Transcription

1 Seizures & Status Epilepticus Management Airway, Breathing, Circulation Don t Ever Forget Glucose If on arrival the seizure is continuing treat with Lorazepam. This should be titrated if other antiepileptic drugs (AED) have already been given. Use the epilepsy-seizure proforma supplied Emergency treatment status epilepticus Pre-hospital stage Early status Diazepam mg given rectally, repeated once 15 minutes later if status continues to threaten, or midazolam 10 mg given buccally If seizures continue, treat as below Lorazepam IV 0.1 mg/kg (usually a 4 mg bolus, repeated once after minutes; rate not critical) Give usual AED medication if already on treatment For sustained control or if seizures continue, treat as below. Established status Refractory status* Phenytoin infusion at a dose of mg/kg at a rate of 50 mg/minute or fosphenytoin infusion at a dose of mg phenytoin equivalents (PE)/kg at a rate of mg PE/minute and/or Phenobarbitone bolus of mg/kg at a rate of 100 mg/minute General anaesthesia, with one of: o propofol (1-2mg/kg bolus, then 2-10mg/kg/hour) titrated to effect. o midazolam ( mg/kg bolus, then mg/kg/hour) titrated to effect. o thiopentone (3-5mg/kg bolus, then 3-5mg/kg/hour) titrated to effect; after 2-3 days infusion rate needs reduction as fat stores are saturated. Anaesthetic continued for hours after the last clinical or electrographic seizure, then dose tapered *In the above scheme, the refractory stage (general anaesthesia) is reached 60/90 minutes after the initial therapy. In some situations, general anaesthesia should be initiated earlier and, occasionally, should be delayed. Experience with long-term administration (hours or days) of the newer anaesthetic drugs is very limited. The modern anaesthetics have, however, important pharmacokinetic advantages over the more traditional barbiturates. Any pre-existing AED therapy should be continued at full dose, and any recent reductions reversed. Treating status epilepticus in adults General measures

2 1st stage (0 10 minutes) Secure airway and resuscitate Administer oxygen Assess cardiorespiratory function Establish intravenous access Early status 2nd stage (0 30 minutes) Institute regular monitoring Consider the possibility of non-epileptic status Emergency AED therapy Emergency investigations Administer glucose (50 ml of 50% solution) and/or intravenous thiamine (250 mg) as high potency intravenous Pabrinex if any suggestion of alcohol abuse or impaired nutrition Treat acidosis if severe 3rd stage (0 60 minutes) Establish aetiology Alert anaesthetist and ITU Identify and treat medical complications Pressor therapy when appropriate 4th stage (30 90 minutes) Transfer to intensive care Establish intensive care and EEG monitoring Initiate intracranial pressure monitoring where appropriate Initiate long-term, maintenance AED therapy Established status Refractory status Emergency investigations Blood should be taken for Glucose, U&E,LFT Calcium and Magnesium, FBC Blood clotting, Blood gases, AED drug levels if applicable; 5ml of serum and 50ml of urine samples should be saved for future analysis, including toxicology, especially if the cause of the status epilepticus is uncertain. Chest radiograph to evaluate possibility of aspiration. Other investigations depend on the clinical circumstances and may include brain imaging, lumbar puncture. Observations/Monitoring Regular neurological observations and measurements of pulse, blood pressure, temperature. ECG, biochemistry, blood gases, clotting, blood count, drug levels. Patients require the full range of ITU facilities and care should be shared between anaesthetist and neurologist. EEG monitoring is necessary for refractory status. Consider the possibility of non-epileptic status. In refractory status epilepticus, the primary end-point is suppression of epileptic activity on the EEG, with a secondary endpoint of burst-suppression pattern (i.e. short intervals of up to 1 second between bursts of background rhythm). First fit Presentation Initial diagnosis is based on a detailed description of the events immediately before, during and immediately after a seizure, together with a full medical history and an eyewitness account of the event(s) You are in the best position to obtain a complete history of what occurred exactly from accompanying paramedics or family. This is very important for a first fit description. Record also the names of any witness to the first fit. What type(s) of seizure?

3 Seizures are described using the International Classification of Seizures: o partial: simple partial (consciousness not impaired) complex partial (impairment of consciousness) o partial seizures may evolve into secondary generalised seizures o generalised (no focal onset): absence myoclonic clonic tonic tonic-clonic atonic, infantile spasms o unclassified epileptic seizures usually used when an adequate description is not available Is it epilepsy? The diferential diagnosis includes syncope Stokes-Adams attacks TIAs Rigors hypoglycaemia More than one seizure needs to be considered for an accurate diagnosis Misdiagnosis often results from a failure to distinguish epileptic seizures from seizures which do not originate in the brain Diagnostic techniques Full physical and neurological examination Comprehensive investigative service for patients with epilepsy o both EEG and neuroimaging should be available Action following diagnosis It is recommended that all people having a first seizure should be seen as soon as possible (within 2 weeks) by a specialist in the management of the epilepsies to ensure precise and early diagnosis and initiation of therapy as appropriate to their needs If the patient experiences focal neurological signs, or severe prolonged or very frequent seizures, he or she should be urgently referred or admitted Patients should receive initial counselling including: o information about epilepsy for the patient and family/carer o advice about what to do during a seizure o advice regarding driving and employment/education issues Drug therapy should only be started once the diagnosis of epilepsy is confirmed except in exceptional circumstances that require discussion and agreement between the

4 prescriber, the specialist and the individual and their family and/or carers as appropriate Algorithm for Paediatric Seizure Management Immediate IV Access Give IV Lorazepam 0.1mg/kg over sec Give IV Lorazepam 0.1mg/kg over sec No IV acess Give Diazepam 0.5mg/kg PR Give Paraldehyde 0.4ml/kg PR with same volume of olive oil Call for senior help and give Phenytoin 18mg/kg IV/IO over 20min & Paraldehyde 0.4ml/kg PR with same volume of olive oil (if not already given) Or if already on phenytoin give Phenobarbitone 10mg/kg over 10 minutes and Call anaesthetist Midazolam mg/kg bolus, then mg/kg/hr titrated Thiopentone 3-5mg/kg bolus then 3-5mg/kg/hr titrated Anaesthetic continued for hours after last seizure the dose tapered

5 Algorithm for adult Seizure Management Immediate IV Access Give IV Lorazepam 4mg/kg over 2min If titrate IV Lorazepam 4mg/kg over 2min If IV Phenytoin 18mg/kg IV max rate 50mg/min or IV Phenobarbital 10mg/kg, max rate 100mg/min if patient is already on phenytoin Paraldehyde 5-10ml deep IM or PR as 10% enema in 0.9% saline and Call anaesthetist Midazolam mg/kg bolus, then mg/kg/hr titrated Thiopentone 3-5mg/kg bolus then 3-5mg/kg/hr titrated Anaesthetic continued for hours after last seizure the dose tapered