EPILEPSY

EPILEPSY DEFINATION OF EPILEPSY:  Epilepsy refers to any type of recurrent convulsions produced by paraoxysmal excessive neuronal discharges in different parts of brain;it is caused by variety of cerebral and non cerebral disorders and implies chronocity of seizures. INTRODUCTION  Epilepsy is a symptom of brain disorder involving paraoxysmal neuronal discharge sufficient to cause effects such as recurrent seizures with disturbances of consciousness.  These abnormal electrical activity can be detected by electroencephalography.  More prevalent in young & mentally or physically impaired affecting over 1% population. CLINICAL ASPECTS  Epilepsy is characterized by seizures that are chronic & recurrent .  In addition to seizures there may be other features such as headache, changes in mood, energy level, confusion & memory loss. CAUSES OF EPILEPSY  Idiopathic epilepsy  Symptomatic or secondary epilepsy -febrile convulsions  Intracranial causes -space occupying lesions -trauma -vascular defects -infections -cerebral palsy -rubella syndrome -phakomatoses -AIDS -meningitis  Systemic causes -hypoxia -hypoglycemia -inborn errors of metabolism -drug overdose or withdrawal (anticonvulsants, barbiturates, alcohol, opioids, benzodiazepines) DIFFERENT FORMS OF EPILEPSY TYPE SUBTYPE MAIN FEATURES LOSS OF CONCIOUSNESS, TONIC PHASE, CLONIC PHASSE, TONGUE BITTING, INCONTINENCE,LAST FOR LESS THAN 5min BRIEF PERIOD OF UNRESPONSIVENESS LAST FOR LESS THAN 30 sec GENERLIZED TONIC-CLONIC SEIZURES (GRANDMAL) ABSENCES (PETITMAL) DIFFERENT FORMS OF EPILEPSY TYPE SUBTYPE PARTIAL SEIZURES SIMPLE (JACSONIAN EPILEPSY) COMPLEX (TEMPORAL LOBE EPILEPSY) OTHERS MYOCLONIC ATONIC MAIN FEATURES MOTOR, SENSORY, AUTONOMIC OR PSYCHIC FEATURES IMPAIRED CONSIOUSNESS, AUTOMATIC REPETATIVE ACTS GRANDMAL EPILEPSY  It usually begins in childhood or sometimes at puberty.  There is aura followed by loss of loss of conciousness, tonic & clonic convulsion & prolonged recovery.  Aura may consists of mood change, irritability, hallucination or headache.  The attack begin suddenly with total body tonic spasm & loss of conciousness. GRANDMAL EPILEPSY  Initially face becomes pale & pupils dilate head & spine are thrown into extension & glottic & respiratory muscle spasm may cause brief cry & cyanosis.  Tonic phase passes in less than a minute into clonic phase where there are repetitive jerky movements of lips, tongue, trunk, limbs.  Profuse salivation with bruxism & tongue biting GRANDMAL EPILEPSY  Occasionally vomiting  Urinary or fecal incontinence.  Autonomic phenomena such as flushing, hypertension & tachycardia  Clonus is followed by state of flaccid semi-coma for 1015min.  Confusion & headache common afterwards.  Patient sleep for next 12 hours or more before full recovery. GRANDMAL EPILEPSY  The attack is followed by transient paralysis or agrresive behaviour.  Complications from major convulsions can be trauma ,brain damage. PETIT-MAL SEIZURES  It comes more often during childhood and are     characterised by: minimal or no movements,except eye blinking. Brief sudden loss of awareness or of concious activity which may last for seconds. Frequent recurrence. Learning difficulties. SIMPLE PARTIAL SEIZURES  It can be motor ,sensory or behavioural and confined     to one area and include: Muscle contractions of specific body part. Abnormal sensations. Sometimes nausea,sweating,skin flushing and dilated pupils. Other localised symptoms. PARTIAL COMPLEX SIEZURES  It is characterised by :  Automatism such as lip smacking and chewing      movements or facial grimacing. Abnormal sensations Nausea,sweating,skin flushing and dilated pupils, sometimes. Recalled emotions. Changes in personality or alertness. Sometimes disorientation,confusion and amnesia,or loss of conciousness. DENTAL ASPECTS  Epilepticus have good and bad phases and dental treatment should be carried out in in good phase where attacks are infrequent.  Whille carrying out dental t/t in epileptic patients a strong mouth prop should be kept in position and oral cavity should be kept free of debries.  Dental apparatus must be kept away from the are around the patient.  Drugs which interfere with anti-convulstant is          contraindicated like:Alcohol Chlorpromazine Enflurane Ketamine Lidocaine Metronidazole Quinolone Tramadol Tricyclic antidepressant  Concious sedation in epilepsy should be safe,stress reduction should reduce the chance fit.  Avoid electronic dental analgesia.  Acrylic is probably better used for prosthesis than porcelain as it is more resilient FACTORS PRECIPITATING FITS IN SUSCEPTIBLE SUBJECTS  Withdrawal of anti-convulsant medication  Epileptogenic drugs  Fatigue,starvation or stress.  Infection  Menstruation  Flickering lights DIAGNOSIS OF EPILEPSY  It involves history of recurrent seizures,but some patients with known epilepsy may,because of stigma,not disclose the history.  Disorders that may show features resembling seizures include transient ischaemic attacks,rage or panic attacks and any disorders that causes loss of conciousness tremors or tics.  A physical examination includes detailed neuromuscular       examination. An electroencephalograph{EEG} usually confirms the presence of seizures and sometimes location of lesion. Magnetic resonance imaging{MRI} and CSF investigations may be indicated. Other tests:Full blood pressure Blood chemistry/blood glucose. Liver /renal function test. Lumber puncture and CSF analysis. GENERAL MANAGEMENT  It may include medical treatment or surgical treatment of tumors or brain lesions.  Propylaxis of epilepsy with anti-convulsant typically started with single drug,raising doses until disorded is controlled.  Most patients with major epilepsy having more than one attack in an year need to be maintained on anticonvulsant.  Anti-convulsant are of two broad groups: GABA or receptor potentiators  Neuronal inhibitors  A second line drug should be given only if a single agent in a maximal doses fail to control fits. ANTI-CONVULSANT T/t OF EPILEPSY SUBTYPES TYPES OF EPILEPSY Grand mal 1ST CHOICE DRUGS Carbamazepine, valproic acid 2ND CHOICE DRUGS Primidone Petit mal Valproic acid or ethosuximide clonazepam Partial complex seizures Carbamazepine primidone Anti-convulsant drugs :uses and adverse effects DRUGS Carbamazepine USE TLE GM SYSTEMIC ADVERSE EFFECTS Ataxia, drowsiness, leukopenia, lupoid syndrome ORAL ADVERSE EFFECTS Dry mouth, erythema multiforme, dyskinesias Purpura Gingival swelling,Dental annomalies, Erythema multiforme,ulcer Valproate Phenytoin GM PM GM TLE Drowsiness, bleeding diathesis Cerebellar damage, hirsutes, nephrotic syndrome, hyperglycemia Ethosuximide PM Lupoid syndrome,renal damage,eosinophilia Primidone GM TLE PM Drowsiness, Ataxia, Oculomotor palsy Megaloblastic anemia Gabapentine GM PM Topiramate GM PM GM:- GRAND MAL ; TLE:-TEMPORAL LOBE EPILEPSY; PM:-PETIT MAL PATHO-PHYSIOLOGY OF EPILEPSY  Epilepsy is not a disease but symptom that represents primary form of brain dysfunction.  Adult onset epilepsy indicates structural lesion of brain.  Clinical seizure activity develops if abnormal discharge is propagated along neural pathways.  If discharge remains localized within a focal area than partial seizure develops & if it continues to spread, generalized seizure occur.  Clinical manifestation of seizure depend on focus of origin & region of brain.  Seizure can also arise in normal neurologic tissues caused by systemic metabolic & toxic disorder.  Deficiency in oxygen, glucose or calcium ion create a membrane instability. MANAGEMENT OF TONIC-CLONIC SEIZURES  CONVULSIVE PHASE: STEP 1 2 3 4 Supine position of patient. prevent injury to patient. soft object under head soft object between teeth loosened tight clothing. Initiate basic life support. Monitor vital signs.  POSTICTAL PHASE: STEP 5: 6: Initiate basic life support permit patient to recover, contact physician. 7: discharge patient in company of responsible adult. GRANDMAL STATUS: STEP 1: supine position of patient. 2: prevent injury to patient. 3: initiate basic life support. 4: monitor vital signs. 5: administer anticonvulsant drug diazepam, 2mg/min slowly I.V phenobarbitol, 25mg/min slowly I.V 6: summon medical help Investigations       Physical and psychiatric diagnosis EEG (Electroencephalograph ) Tomographies (Axial, Magnetic) Psychological research Detailed History Seizures observation Diferential Diagnosis  Syncope  Psychological disorders  Metabolic disturbances  Migraine  Sleep disorders  Movement disorders Medicinal Management Antiepileptic medication  Valproic Acid (Depakine) First rate:primary-reductions, muscle spams, tonic spasms, Second rate: Focal, All  Carbamazepine (Tegretol) First rate: Focal Second rate: tonic spasms  Phenitoin sodium (Epanutin) First rate: Focal, origin tonic spasms Antiepileptic medication Phenobarbital (Gardenal) Secondary rate: Focal, Generalized tonic spasms Primidone (Mysoline) Secondary rate: Focal, Tonic spasms Clonazepam (Rivotril) Secondary rate: Reductions, Muscle spasms, All Gabapentin (Neurontin) Lamotrigine (Lamictal) Secondary rate: Resistant, Focal, Generalized Side effects of antiepileptic medication.  The eventual severe side effects are depression, ataxia, and hematological disorders.  The milder social side effects of these medication are hypertrichosis, obesity, oedema of the gums and hardness of facial characteristics.  Exposure to AED in utero  2-3 x inc in background rate (1-2%)  cardiac  cleft lip/palate  neural tube  polytherapy increases risk  retrospective small studies – ‘older’AEDs Rate of dose increments  Typical doses for phenytoin –300-400 mg once daily, carbamazepine – 200-600 mg twice daily, valproate 500-1000 mg twice daily.  The commonest cause of failure of carbamazepine therapy is non-compliance as a result of unpleasant adverse effects (dizziness, drowsiness, nausea, vomiting).  It is reasonable to start slow (eg 100-200 mg twice daily) and increase by 100-200 mg/day every 4-7 days until a final desired dose (ranging from 600-1600 mg/day) is obtained. Final dose depends in part on type and severity of epilepsy Discontinuation of treatment  If seizure freedom has been achieved for 2-5 years, treatment discontinuation is an option.  Seizure recurrence in adulthood is highest for JME (80% recurrence) vs 40-50% for other subtypes.  75% of relapses occur within first 12 months, and at least half of those relapses occur in the first three months.  No driving during tapering. Tapering should occur over 6-10 weeks for all drugs except barbiturates and benzodiazepines, which probably should be tapered over 10-16 weeks. Other Epilepsy Treatments  Vagal Nerve Stimulator (VNS)  Diet Modification Vagal Nerve Stimulator (VNS)   Device is implanted to control seizures by delivering electrical stimulation to the vagus nerve in the neck, which relays impulses to widespread areas of the brain Used to treat partial seizures when medication does not work Ketogenic diet  Ketosis improves seizure control  The basic protocol calls for a diet with a fat-to– carbohydrate-plus-protein ratio of 4 to 1 on a caloric basis. A modification of the diet uses medium-chain triglyceride (MCT) oil and allows for a greater amount of carbohydrate.  Beneficial in a subset of patients who have not responded to antiepileptic drugs. Protocol for epileptic patient  Consider having serum level of AED’S  Avoid hypoglycemia and fatigue  Use anxiety reduction protocol  Before appointment    Hypnotic agent to promote sleep on night before surgery Sedative agent to reduce anxiety Morning apointment in order to reduce reception room time Nonpharmocologic means Frequent verbal reassurance  Distracting conversation  Don’t surprise the patient  No noise  Surgical instrument out of patients sight  Relaxing background music   Non pharmacologic means  Local anesthesia of sufficient intensity and duration  Nitrous oxide  Iv anxiolytics  AFTER SURGERY  Sufficient instruction for postoperative care  Patient information on expected pst surgical sequele INITIAL DIAGNOSIS & MANAGEMENT  Primary care  take history from patient and witness --district-based       education make initial diagnosis - clinical nurse specialist make initial referral -local protocols provide information for the patient - referral template/agreed dataset may initiate drug therapy (paper/computerised) arrange early review - information source for patient (paper/computerised)  Secondary care  confirm diagnosis - local protocols  undertake investigations - hospital-based team  initiate drug therapy - clinical nurse specialist  provide access to counselling -template for consultants letter  shared record Suggestions for starting and using antiepileptic drugs Main Choices Carbamazepine Sodium Valproate Phenytoin Maintenance dose 200-1600 mg daily 600-2500 mg daily 150-600 mg daily Starting doses 100mg bd for 2 weeks 600 mg daily 200 mg daily Older Alternatives Primidone, Primidone, Clonazepam, indications seizure type partial OR generalised tonic-clonic absence partial or generalised adverse effects & limitations to use sedation, behavioural problems nausea, vomiting, sedation, tolerance Dental Management  Complete medical history regarding the type n frequency of seizure episode prior to t/t  Reduce stress on pt by psychobehaviourail prepration,sedation etc  Use of dental chair light is avoided  Drugs such asphenothiazines,iv local anesthesia,methohexitone,tricylics,alcohol  Due to use of AED’S[dilantin sodium],typical gingival hyperplasia may occur surgical removal may be done in certain cases  In dental t/t appoinments should be kept short  Importance of tooth brushing procedure and regular dental review must be stressed  If appliances are indicated they must be fixed  Any prostheses should be radiopaque Patient protection  If the pt is on floor gently restrain the victims harms and legs from gross movemet  Head injury should be prevented by using well padded head rest  A soft handkerchief or large gauze piece of 4’’ by4’’ shoild be used ACUTE MANAGEMENT OF TONIC-CLONIC SEIZURES IN ADULTS  General mangement  During the attack, take measures to avoid the patient being injured (eg. protect them from hot radiators, hot water, stairs, sharp objects etc)  After the convulsive movements have subsided, put the patient in the recovery position and check that the airway is not obstructed and that there are no injuries  When the patient has fully recovered, reassure them  Patients in whom the seizure is associated with acute or chronic alcohol excess may need to be referred for general management (for example, to treat hypoglycaemia or infection)  If the patient is a pregnant woman, she should be transferred to hospital immediately The single seizure  Individual episodes usually stop spontaneously within 3 minutes, although in some patients the pattern is different and they can last longer.  Recovery from such individual episodes is not speeded by emergency drug treatment and their management should be as outlined above. Referral advice  If the patient has a diagnosis of epilepsy and is otherwise well controlled, early referral is usually not necessary and they should be reviewed at their next appointment with the neurologist or epilepsy nurse.  The appointment may need to be brought forward if the fit might affect the patient’s employment or driving status. Prolonged or serial Seizures  A patient presenting with a ‘prolonged’ seizure (ie tonic-clonic movement) lasting 5 minutes or more or, with serial seizures (3 or more in an hour), should be managed as set out in the general management advice above.  In addition, give rectal diazepam 10-20mg and repeat the dose after 15 minutes if necessary; buccal midazolam is an alternative, although it is currently unlicensed for this indication. Status Epilepticus  Status epilepticus is defined as either a run of discreet seizures without full recovery in between fits, or continuous seizures lasting for 30 minutes.  The mortality and morbidity of generalised tonic/clonic status is high, and it is important to control the fits as soon as possible. The following measures should be instituted as soon as status has been diagnosed. Management  Protect the patient from injury. Do not leave the patient alone whilst fitting or recovering; do not restrain the patient or put anything, including an oral airway, in the mouth during a seizure.  Arrange for an ambulance to transfer the patient to hospital immediately  Assess cardiorespiratory function - record blood pressure and pulse rate and, if possible, and not contraindicated, give oxygen.  Measure blood glucose and if the patient is hypoglycaemic give 1mg glucagon IM or IV glucose (see page 39 for further details).  Try to discover evidence of previous epilepsy and/or whether the patient is on any anti-epileptic drugs. Also try to establish the time of onset of the episode. Record this information and send it with the patient to hospital.  Drug treatment  While waiting for the ambulance give diazepam 10- 20mg rectally (use rectal solution; absorption from suppositories is too slow) and repeat the dose after 15 minutes if status continues to threaten.  Buccal midazolam is an alternative.  If seizures continue, and you carry it, consider giving IV lorazepam 0.1mg/kg into a large vein (usually 4mg bolus, repeated once after 10-20 minutes) or IV diazepam (as Diazemuls) 10mg over 2-5 minutes. References Medical emergencies by MALAMED/CAWSON Textbook of pedodontia by FINN Oral surgery by PETTERSON Google.com