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					 DEPARTMENT OF NEUROLOGY                                                                LECTURE 4
 WOMEN’S AND CHILDREN’S HOSPITAL
 FIFTH YEAR MEDICAL STUDENT LECTURE


         SEIZURES AND NEUROLOGICAL EMERGENCIES
                    Dr. J.I. Manson & Dr. K.J. Abbott, Paediatric Neurologists

     INTRODUCTION
     At the onset, it is necessary to recognise that the term "seizure" means different things
     to different people. To the general public it may refer to any kind of attack of a
     sudden nature. Neurologists use the term mainly in the context of epileptic seizures,
     but some medical professionals would use the term in other contexts as well, eg.
     breath-holding "seizures" or convulsive "seizures". It is advisable not to use the term
     "seizure", therefore, except in the context of a qualifying term that clarifies one's
     meaning.

     In the context of this lecture, the term "seizure" will refer to epileptic seizures, and
     will not be used in the context of non-epileptic events.

     This lecture will cover the following areas:
             A)     Epileptic seizures, their differential diagnosis and treatment
             B)     Paediatric neurologic emergencies

A)   EPILEPTIC SEIZURES (Epilepsy):
            Definition - Epilepsy may be defined as "a recurrent transient disturbance of
            cerebral function caused by a synchronous discharge of nerve cells (neurones)
            of the brain".

     INCIDENCE OF EPILEPSY
     Commonest disorder in paediatric neurology. 85% of epileptics develop
     manifestations of the disorder before the age of 20 years.
     Incidence of seizures at different ages:
            Neonates               12 per 1000
            Pre-school             50 per 1000 (includes febrile convulsions which are not
                                           conventionally regarded as epileptic seizures)
            School-age             8 per 1000
            Idiopathic epilepsy shows its maximum age of onset between 5 and 15 years.

     If one excludes febrile convulsions, then during the first year or two of life, causes
     such a birth asphyxia and congenital abnormalities predominate among the causes of
     epilepsy. In school-age years, idiopathic epilepsy is the predominant type of epilepsy.
     In adults, organic conditions such as brain tumours, head injuries and cerebrovascular
     disease, become more prominent.

     CLASSIFICATION OF EPILEPSY
     This is a confusing area, because of there being different types of classification. This
     confusion is due to the fact that there are several fundamental systems of classification
     of the epilepsies:
             I)      Descriptive (International) Classification* of seizures
             II)     Aetiological
             III)    Developmental (age-related)
             IV)     Syndromal, eg. West Syndrome (III & IV overlap considerably)

     * The international Classification is currently under review.
                                                 -1-
SEIZURES & NEUROLOGICAL EMERGENCIES                                         LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS


I     DESCRIPTIVE CLASSIFICATION
      Generalised Seizures
      The term seizure is generally used to denote an epileptic event, ie. an attack
      secondary to a synchronous discharge of nerve calls of the brain.
      1)     Bilaterally symmetrical, without focal onset:
             a) Absence (formerly petit mal)
             b) Myoclonic (brief, single, momentary, jerking movements)
             c) Clonic (repetitive jerking movements)
             d) Tonic (prolonged muscular stiffening of limbs or trunk)
             e) Tonic-clonic (formerly referred to as grand mal)
             f) Atonic

       2)     Partial (Focal) Seizures (seizures beginning locally)
              a) Simple partial (focal) seizures (consciousness not affected) eg.
                 Jacksonian seizures, with spread of focal clonic activity from face
                 to limb.
              b) Complex partial (focal) seizures (impaired consciousness) eg.
                 temporal lobe seizures.
              c) Partial (focal) seizures with secondary generalisation.

              Partial Seizures may be classified on the basis of the region of the
              cortex from which they arise:
              i) pre-motor cortex (supplementary motor seizures)
              ii) pre-central cortex (Jacksonian)
              iii) parietal (sensory)
              iv) occipital (visual)
              v) temporal
              (Seizures in infancy may take atypical forms, eg. infantile spasms).

II     AETIOLOGICAL CLASSIFICATION
       1)   Idiopathic (primary epilepsy) (approx. 60% of cases).
            This type is that in which the epilepsy is not secondary to some other
            known cause, but appears to be a primary disturbance in the cerebral
            rhythms. Such cases are often familial or genetic in nature. Idiopathic
            epilepsy is commonly, but not always, generalised. Patients usually
            have a normal neurological examination.
       2)   Symptomatic Epilepsy
            There is a known cause for the epilepsy (approx. 40% of cases)
            Symptomatic epilepsy may be partial or generalised.
              Common causes of symptomatic epilepsy in childhood are:
              1.   Congenital brain defects
              2.   Trauma
              3.   Birth asphyxia
              4.   Infections (either congenital or post-natal)
              Less common causes are:
              1.     Tumours
              2.     Metabolic conditions such as hypoglycemia, hypocalcaemia,
                     amino acid or organic acid disorder
              3.     Familial neurodegenerative diseases eg. Tay-Sach’s disease
              4.     Chromosomal disorders, eg. Down’s syndrome
              5.     Neurocutaneous syndrome, eg tuberous sclerosis
                                          -2-
SEIZURES & NEUROLOGICAL EMERGENCIES                                          LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS


       3)     Cryptogenic
              In a significant proportion of cases the cause of the epilepsy is
              unknown, despite the most searching investigations and enquiries, eg.
              many cases of West’s Syndrome and Lennox-Gastaut Syndrome.
       4)     Epilepsy where both hereditary and environmental causes play a part
              in aetiology, eg. brain tumour patients who present with epilepsy, are
              more likely to have a family history of epilepsy, than those who
              present with other symptoms.


III    DEVELOPMENTAL CLASSIFICATION. (OVERLAPS WITH SYNDROMAL
       CLASSIFICATION).
       In paediatrics the most satisfactory classification of epilepsies, from the point
       of view of clinical practise, is one based on the age of onset. The aetiology,
       manifestations and management of epilepsy vary greatly with the age of onset.
       Thus, epilepsies of childhood may be classified as follows:
       1.     Neonatal seizures                                        (first 3 weeks)
       2.     West’s Syndrome (infantile spasms)                       (3/12 – 9/12)
       3.     Febrile convulsions                                      (3/12 to 5 years)
       4.     Benign focal epilepsy                                    (5 to 10 years)
       5.     Absence (petit mal) epilepsy `                           (5 to 10 years)
       6.     Idiopathic generalised tonic clonic epilepsy             (5 to 15 years)
       7.     Juvenile Myoclonic epilepsy                              (10 to 20 years)
       8.     Photo-convulsive epilepsy                                (10 to 20 years)
       9.     Temporal lobe epilepsy                     (all ages including infancy)
       10.    Secondary partial or generalised epilepsy resulting from brain damage
              or malformation
       For the general practitioner, it is necessary to be aware of the clinical aspects
       of the following seizure types in order of importance, viz, generalised tonic-
       clonic, febrile convulsions, neonatal seizures, complex partial (temporal lobe),
       absence, infantile spasms, photoconvulsive seizures, and benign Rolandic
       seizures.


      1.      NEONATAL SEIZURES
              a) Seizures are often fragmentary, migratory, and may cause
                 apnoea. Often not recognised as seizures when manifested as
                 minimal motor activity.
              b) Incidence of 1% in neonates.
              c) Age of onset is important, seizures presenting in first 48 hours,
                 more likely to be due to birth asphyxia – worse prognosis.
                 Seizures after 48 hours – generally have a better prognosis.
              d) Consideration of aetiology is based on age of onset.
       In the first 48 hours, birth asphyxia, birth trauma and intracranial haemorrhage
       are likely causes. After 48 hours, metabolic causes, drug withdrawal due to
       maternal addiction, polycythemia and benign familial neonatal seizures may
       be considered. Infections (bacterial meningitis and herpes simplex
       encephalitis), and hypoglycaemia should be considered at any stage of the
       neonatal period, likewise vitamin B6 dependency.


                                          -3-
SEIZURES & NEUROLOGICAL EMERGENCIES                                          LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS


       Investigations
       1)     Blood glucose, cal., mag., elect., BUN., CBC.
       2)     L.P.
       3)     C.A.T. or cranial ultrasound
       4)     Metabolic work-up:
              a)     amino acids
              b)     organic acids
              c)     ammonia
              d)     Trial of B6 therapy

       Conditions often overlooked as a cause of neonatal seizures.
       Polycythaemia, benign neonatal familial seizures and 5th day seizures (a
       benign syndrome of neonatal seizures presenting on the 5th day, with a self-
       limiting course).

       EEG in Neonatal seizures
       The EEG may be helpful in differentiating seizures from other causes of
       apnoea in the newborn. It may also be helpful in detecting herpes simplex
       encephalitis, which may present after the first week of life, and in which focal
       periodic high voltage slow waves may be a feature.

       Finally, the EEG can be of help in prognostication. In cases of birth asphyxia
       a burst-suppression pattern suggests a bad prognosis. A normal EEG, or one
       showing unifocal spike discharges, suggests a good prognosis.

2.     INFANTILE SPASMS (WEST SYNDROME)
       This is an important condition to recognise. The spasms occur in a series of
       flexion spasms of head, trunk and limbs, often descriptively called salaam or
       jack-knife spasms. The spasms may be mistaken for colic, or Moro reflex, by
       those unaware of their significance.

       The EEG shows hypsarrhythmia, (multifocal high voltage spikes). About 60%
       of cases are secondary to organic or metabolic brain disease. Perinatal brain
       damage, congenital malformations, and tuberous sclerosis are the commonest
       causes. 40% are cryptogenic (of unknown cause).
       The prognosis is grave. Almost all the secondary cases show significant
       intellectual handicap. About 60-70% of cryptogenic cases will be
       intellectually handicapped. Early recognition is important. The prognosis is
       arguably improved with early institution of ACTH or Prednisolone, in
       cryptogenic cases.

       All cryptogenic patients should be fully investigated with head scanning,
       metabolic studies (amino acids, etc), and careful examination of the fundi
       (Aicardi Syndrome, chorio-retinitis, etc), and examination of the skin with an
       ultraviolet light, to check for possible tuberous sclerosis.

       The neurological status of the infant at the time of presentation is an important
       prognostic guide.

3.     FEBRILE CONVULSIONS (FCs)
       Definition: Febrile convulsions may be defined as seizures occurring between
       3 months and 5 years of age, associated with fever, but without evidence of
                                          -4-
SEIZURES & NEUROLOGICAL EMERGENCIES                                         LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS

       intracranial infection or defined cause. Seizures with fever in a child who has
       already had a previous non-febrile seizure are excluded. Febrile seizures are
       to be distinguished from epilepsy, which is characterised by recurrent non-
       febrile seizures.

       Incidence: About 4-5% of children under 5 years will have at least one
       febrile seizure.

       Classification
       1.     Benign FCs (approx 90%)**
              (a) brief (usually 1-2 minutes)
              (b) generalised
              (c) tonic, clonic, tonic-clonic or hypotonic
              (d) rapid recovery (child usually fully recovered by time presents to
                    doctor)
              (e) single, not multiple
              (f) often a family history of benign FCs
              (g) 3 months to 5 years
              (h) excellent prognosis
              (i) management is predominantly supportive with reassurance, anti-
                    pyretics etc
              **Febrile convulsions are very alarming for the parents, and
              considerable reassurance may be required.

       2.     Complicated FC (approx 10%)
              (a) prolonged > 5 minutes, or multiple within 24 hours
              (b) often focal (partial)
              (c) tonic, clonic, tonic-clonic, hypotonic
              (d) recovery delayed, eg. Todd’s paralysis (a transient post-
                  convulsion hemi-paresis lasting less than 24 hours)
              (e) consider possibility of meningitis
              (f) may have underlying neurological or development disorder
              (g) prognosis less favourable (there is a possibility of subsequent
                  epilepsy or brain damage
              (h) treatment is a medical emergency, as for status epilepticus

       Prognosis:
       (a) For febrile seizures:
            After a first febrile seizure about 30-40% will recur (under 1 year 50%
            recurrence; over 3 years 20% recurrence). After each successive febrile
            seizure, the risk of further febrile seizures increases.
       (b) For epilepsy:
            Risk for epilepsy depends on the presence or absence of the following
            factors:
            i) A family history of non-febrile seizures
            ii) Abnormal neurological or developmental status prior to febrile
                 seizure.
            iii) An atypical febrile seizure, such as a prolonged or focal seizure, or
                 recurrent within 24 hours.



                                          -5-
SEIZURES & NEUROLOGICAL EMERGENCIES                                         LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS

            The risk of subsequent epilepsy in febrile convulsions without any extra
            risk factor is of the order of 2% (ie close to normal). The risk of
            subsequent epilepsy depends on the number of risk factors present.
            It is important to recognise that febrile convulsions, if sufficiently
            prolonged, may result in permanent severe brain damage and/or
            epilepsy. Brain damage almost certainly does not occur with
            convulsions lasting less than 30 minutes. Between 30 and 60 minutes
            there is a small, but definite risk of brain damage, with the likelihood of
            brain damage rising rapidly after 60 minutes.
            Hence the treatment of a prolonged febrile convulsion (greater than 3-5
            minutes) is a medical emergency. (Treatment will be discussed
            subsequently).

4.   BENIGN FOCAL EPILEPSY
     This is a relatively common form of childhood epilepsy (more common than
     absence).
     1.    Seizures commonly nocturnal
     2.    Age of onset between 5-10 years
     3.    Seizures arise from Rolandic or Sylvian cortex, and manifest with speech
           paralysis, twitching or paraesthesias of mouth and/or tongue, dribbling,
           and choking, spreading sometimes to unilateral facial, or Jacksonian
           seizures; the seizures may develop into generalised tonic-clonic attacks, if
           original focal seizures not recognised or treated.
     4.    EEG shows either unilateral or bilateral centro-temporal spike discharges.
     5.    The condition is genetically determined and not associated with organic
           brain lesions, as a rule, and the patients are neurologically normal.
     6.    The prognosis for spontaneous cure is excellent, and the disorder usually
           responds to minimal doses of anti-convulsant therapy.

5.     ABSENCE EPILEPSY (petit mal)
       Relatively uncommon (2-5% of childhood epilepsies). Absence epilepsy is
       now generally accepted as a genetic form of epilepsy, possibly multi-factorial.

       Patients are usually neurologically normal. Age of onset is usually between 5
       to 10years, but can begin any time between 3 years of age and adolescence.
       The attacks consist of brief staring attacks, lasting 5-30 seconds, often with
       slight flickering of the eyes, twitching of the hands and mouth, and arrest of
       normal activities, such as speaking. The attacks are of sudden onset, and
       sudden ending, usually without postictal confusion. Consciousness is lost
       during the attacks; head-dropping occasionally occurs; falling or incontinence
       are rare. The attacks can usually be quite easily provoked by voluntary
       hyperventilation; this constitutes a diagnostic test. The seizures are
       accompanied by generalised 3 per second spike wave activity on the EEG.

       Prognosis
       This is still an area of disagreement. At least 50-75% of cases resolve before
       adult life. About 35% subsequently develop generalised tonic-clonic seizures.
       Late onset of absence and an accompanying photo-convulsive response on the
       EEG, favour the subsequent development of generalised tonic-clonic seizures.



                                          -6-
SEIZURES & NEUROLOGICAL EMERGENCIES                                          LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS



6.     IDIOPATHIC (PRIMARY) GENERALISED TONIC-CLONIC
       EPILEPSY (GRAND MAL)
       This is probably the commonest form of childhood epilepsy, presenting
       between 5 years of age and 15 years of age. Isolated generalised tonic-clonic
       is one of the more benign forms of childhood epilepsy. Attacks are often
       predominantly nocturnal, and therefore do not interfere with the child’s
       activities. The seizures, although the first attack is very frightening to the
       parents, usually respond well to therapy, and there is an excellent prognosis
       for long-term remission. The seizure type is well known.

       Consciousness is lost immediately, the patient cries out, falls (if standing);
       there is tonic stiffening and extension of limbs and trunk, with facial oral and
       laryngeal musculature involved. Breathing is arrested; the patient becomes
       cyanosed; incontinence of urine and/or faeces may occur; tongue biting and
       bleeding and salivation from the mouth may occur. This tonic phase lasts
       about 15 seconds to 1 minute. The next stage consists of clonic contractions
       of face, limbs and muscles, with gurgling respirations – first rapidly, then
       more slowly, ceasing after 1-2 minutes. The respirations then become regular;
       colour improves; the patient becomes limp and unconscious. After 5-10
       minutes the patient is then rousable, but drowsy. The patient then sleeps for a
       period of several minutes to several hours. Commonly, the interictal EEG
       shows bilateral spike wive activity. The patients are usually neurologically
       normal.


7.     JUVENILE MYOCLONIC EPILEPSY
       An important group of teenagers who present with nocturnal generalised tonic-
       clonic (grand mal) seizures, and have myoclonic jerks in the morning after
       waking. Some of these patients have photosensitivity or absence. They
       respond very well to Valproate, which needs to be given for many years.


8.     PHOTOSENSITIVE EPILEPSY
       This form of epilepsy most often presents in the early teenage years (range 10
       to 20 years). It is provoked by flickering light, eg. watching a faulty TV set, at
       the beach, or travelling by car on a sunny day, at a disco, or when playing
       electronic TV or video games.
       The seizure usually commences with jerking, clonic movements of the eyes
       and head, then spreads to the limbs and the whole body culminating in a
       generalised clonic seizure. At the beginning of the seizure, consciousness is
       retained, but when the seizure becomes generalised, consciousness is lost. The
       EEG accompaniment consists of generalised polyspikes and spike wave bursts
       in response to photic stimulation at 15-25 c/s.
       The condition is often refractory to initial therapy, but spontaneous
       improvement tends to occur in adult life. Valproate is the drug of choice.
       Photosensitive epilepsy is usually of genetic origin, and very rarely is
       symptomatic of organic brain disease. A photosensitive response to single
       flashes of light is seen in Batten’s disease (late infantile cerebromacular
       degeneration).

                                          -7-
SEIZURES & NEUROLOGICAL EMERGENCIES                                           LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS


9.    TEMPORAL LOBE EPILEPSY (COMPLEX PARTIAL SEIZURES)
      This is an important form of epilepsy for a number of reasons:
      (a)      It is common. 15% of all seizures are temporal lobe seizures. 50% of
               cases of temporal lobe epilepsy begin in the first 10 years of life.
      (b)      It is often misdiagnosed as absence.
      (c)      It is one of the severe forms of childhood epilepsy, which are difficult
               to treat.
      Aetiology
      Commonest cause in childhood is mesial temporal sclerosis, the result of anoxic
      damage to the hippocampal region of the temporal horns, secondary to
      prolonged febrile convulsions. Other causes include birth asphyxia, congenital
      malformations, and infrequently, gliomas.
      Temporal lobe seizures classically manifest as episodes of confusion, and
      unawareness of the surroundings, usually lasting several minutes. The patient
      may have an aura of fear, or an unpleasant smell or taste. There may be
      automatic repetitive lip-smacking, tasting and swallowing, or chewing
      movements. Autonomic changes, such as flushing, pallor, dilatation of the
      pupils, may occur. Various types of confused automatic behaviour such as
      repetitive utterances, purposeless hand movements, walking or running about in
      circles may occur. The patient does not usually fall. After the seizure the
      patient is usually somewhat confused and drowsy, and may sleep for some time.

      Diagnosis is made more difficult by the fact that the routine EEG is often
      unhelpful in temporal lobe epilepsy, as the epileptic discharges arise from the
      inferior surface of the temporal lobes. Special EEG techniques, such as sleep
      EEG and sphenoidal EEG may be necessary for diagnosis. The MRI scan is
      also helpful. MRI scanning is indicated in temporal lobe epilepsy, as it is in all
      persistent partial (focal) forms of epilepsy, unless a clear aetiology has already
      been established.

10.    SECONDARY GENERALISED TONIC CLONIC OR PARTIAL
       EPILEPSY
       Generalised tonic clonic seizures and partial seizures, which commence under
       3 years of age, often accompanied by other forms of epilepsy, or by some prior
       neurological deficit, are in this category. Here the prognosis is not necessarily
       so good, and is dependent on the primary cause. Such cases are often
       secondary to significant brain malformation or damage from early life, and
       may accompany cerebral palsy and/or intellectual disability.


               INVESTIGATION OF CONVULSIVE DISORDERS

DIAGNOSTIC WORK-UP
This is a crucial part of the management of a child with a seizure disorder. The
following steps are taken
1.      History taking
2.      Examination
3.      Investigations



                                           -8-
SEIZURES & NEUROLOGICAL EMERGENCIES                                          LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS


HISTORY TAKING
This is the most important part of the work-up of an epilepsy patient. Certain
essential features must be stressed:
1.      The diagnosis of epilepsy is primarily based on a very detailed description of
        the seizure, given by an eyewitness directly to the doctor. It is most
        undesirable to base the diagnosis of epilepsy on a second-hand account of the
        seizure, or on hearsay. An important source of supportive information is the
        video camera. If there is diagnostic doubt, based on an unclear history,
        parents can be encouraged to take a video of future attacks.
2.      The events leading up to the seizure, the aura (which points to the focus of
        origin), and the duration, frequency, and times of day or night that the seizure
        occurred, as well as the description of the events of the seizure, must be
        recorded. Impairment of language after the seizure may suggest a dominant
        hemisphere origin.

3.     A detailed history of
       (a)    Obstetrical events;
       (b)    Development and school progress (normal, delayed or deteriorating);
       (c)    Past illnesses, such as convulsions, head injuries, meningitis etc;
       (d)    Family history
       (e)    Psychological and social aspects should be recorded;
       (f)    Handedness (right or left) and especially if there has been any change
              of handedness.

EXAMINATION
A detailed neurological and general physical exam must be recorded. Important parts
of the examination include:
1)      Assessment of speech and intellectual functioning. (Epilepsy is a disorder of
        the cerebral cortex). A significant minority of epileptics have associated
        intellectual learning disabilities and neurological disabilities).
2)      Head circumference measurement, and listen for intracranial bruits
3)      Fundus oculi – look for papilloedema, retinal degeneration, chorio-retinitis,
        phakomas, etc.
4)      Although obvious focal neurologic signs are uncommon in epileptics, certain
        physical signs can be most helpful.
        (a)     Slight atrophy of an extremity, (eg. the hand), may suggest a long-
                standing contra-lateral cerebral injury, usually of a congenital or
                perinatal origin.
        (b)     Minor degrees of facial asymmetry have similar significance to (a).
        (c)     Do not forget visual fields. (If child is old enough, test each eye
                separately).
        (d)     Examine the skin carefully for evidence of tuberous sclerosis,
                (depigmented spots may be detected with UV light), neurofibromatosis
                (café au lait spots), and Sturge-Weber syndrome.
        (e)     Observe whether child is right or left-handed.

INVESTIGATIONS
1)   EEG should be done in cases of suspected epilepsy (but may not be necessary
     for febrile convulsions).
2)   Complete blood picture, electrolytes, calcium, fasting glucose, and blood
     urea, for all cases of partial (focal) and generalised non-febrile seizures except
     absence and photoconvulsive seizures.
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SEIZURES & NEUROLOGICAL EMERGENCIES                                         LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS

3)     CAT or MRI scan is indicated for:
       a)   focal (partial) seizures (except typical benign focal epilepsy)
       b)   focal abnormalities on EEG
       c)   focal neurologic signs
       d)   raised intracranial pressure
       e)   deteriorating mental function
       f)   persisting seizures, or worsening seizures
       It should be mentioned that CAT and MRI scans have proved most useful tests
       in investigation of epilepsy. About 1-2% of epileptics who have a scan will be
       found to have a lesion, which is amenable to surgical treatment, eg. tumours,
       focal temporal lobe atrophies, extra-cerebral collections, occult hydrocephalus,
       etc. Much more often a non-surgical focal lesion or congenital abnormality is
       found which provides an explanation for the cause of the epilepsy.

       Although MRI scan provides more detailed information than CAT, CAT is
       adequate to exclude urgent surgically-treatable causes of seizures, and is much
       more readily available. (Children under 10 require anaesthetic for MRI, c.f.
       under 3 for CAT).
       Overall about 40-50% of epileptic patients show an abnormal scan, but as
       previously mentioned, only about 1-2% will be found to have a surgically
       treatable lesion.

4)     EEG in Childhood Epilepsy
       The following points are worth making briefly.
       (a)    The EEG feature suggestive of a seizure disorder is the inter-ictal spike
              discharge. If the discharge is focal, it suggests a focal lesion; if
              generalised, it suggests idiopathic epilepsy. This rule has numerous
              exceptions, however.
       (b)    A normal EEG does not exclude epilepsy, especially in temporal lobe
              epilepsy. Repeated EEG tests, especially in the sleeping state, may be
              necessary to establish the diagnosis.
       (c)    Non-specific changes, eg. excessive amounts of slow-wave activity are
              not of diagnostic help, except in so far as they suggest the presence of a
              focal structural lesion.
       (d)    Provocative Techniques are especially helpful in specific cases, eg.
              hyperventilation in absence, photic stimulation for photic epilepsy, and
              light sleep in temporal lobe epilepsy.
       (e)    EEG – Video Monitoring is an increasingly utilised technique.


             DIFFERENTIAL DIAGNOSIS OF EPILEPSY
NON-EPILEPTIC ATTACKS h more prevalent than epilepsy
                      h diagnosis clinical, on detailed first hand history
                      h home video useful, especially with infants
                      h parents' imitation of child's movements may help

UK HOSPITAL OUTPATIENT STUDY - children referred with "possible epilepsy"
                      h non-epilepsy diagnosis in 35%
                      h epilepsy "doubtful" in 45%
                      h convincing epilepsy approx 20%
                                         -10-
SEIZURES & NEUROLOGICAL EMERGENCIES                                       LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS



DIAGNOSTIC ERRORS include:
                       h accepting inadequate evidence (ie alleged "fit" in
                           school, not seen by parents)
                       h mistaking convulsive-type movements in syncope
                           for epilepsy
                       h assuming epilepsy on basis of past or family
                           history of this.

The EEG cannot prove epilepsy unless a seizure occurs during the test (unusual). 2-
5% of non-epileptic children have paroxysmal ("epileptogenic") changes on EEG
because of their genetic make-up. Children with chronic brain disorders (ie CP) have
higher incidence of such EEG changes yet may not have epilepsy. Likewise, a normal
EEG cannot (except rarely) exclude epilepsy.

Checklist of non-epilepsy:   h SYNCOPES
                             h BEHAVIOURS
                             h SLEEP DISORDERS
                             h NEUROLOGIC EVENTS
                             h FICTITIOUS EVENTS

The most commonly seen episodes vary with age:
      INFANCY      - episodic behaviours/movements
      TODDLER - breath-holding
                   - reflex syncope
      OLDER        - isolated syncopes
                   - stares
                   - sleep disorders
                   - tics
                   - "pseudoseizures"

1)     SYNCOPES - situation/provocation, initial pallor (always ask),
       visual/abdominal symptoms (in older child), brief with restored conscious
       state (immediate sleep is rare). Visible pallor often for ½-1 hour after.

       "Convulsive" syncope - tremors, jerks, extensor stiffening, vocal sounds,
       head/eye movements, are frequent after consciousness lost (due to brain
       anoxia). Must not assume epilepsy on this evidence alone. Urinary
       incontinence occurs in approximately 10% of severe childhood syncope. In
       contrast, hypersalivation does not occur and should suggest epilepsy.

       Forms of Syncope
       h      cyanotic breath-holding (anger, frustration)
       h      reflex vagal syncope (minor trauma, fright)
       These 2 can coexist and there are genetic elements.
       h      vasovagal (upright posture, emotion)
       h      cardiac syncope (usu long QT syndrome) - dangerous - consider when
              exercise related syncope; no known provocation; family history of
              unexplained syncope or sudden death <40yo. Routine ECG and Holter
              monitoring may be required.


                                        -11-
SEIZURES & NEUROLOGICAL EMERGENCIES                                        LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS

2)     BEHAVIOURS - a large variety. Home video most useful with infants,
       where episodes often recur regularly. Video - EEG recordings needed in
       minority of cases.

       h      Episodic movements of infancy - tremors
                                                  - ritualistic incl. masturbation
       h      Stares - ask when? how often? does shaking stop it? Can be absence,
              or focal-type seizure (esp. infancy). Psychogenic stares most common
              in school-aged. In untreated absence epilepsy, stares occur at any time,
              frequently (many daily) and can be induced by 2-3 minute good
              hyperventilation.
       h      Rages, panic attacks - duration and complexity of behaviours usu.
              separate from epilepsy.
       h      Reflex MMs in brain injured - stiffenings in spasticity, tremors or
              clonus, posturings due to episodic discomfort (ie from reflux).
       h      Psychogenic "pseudoseizures" an issue in peripubertal/adolescent
              groups. A conversion reaction rather than conscious deception in great
              majority. May complicate genuine epilepsy (trap for the unwary
              doctor). Triggers include anxiety, predicaments, over-commitment,
              attention seeking, abuse , family dysfunction. Premorbid personality
              usu. average (ie no chronic neurosis etc). Need to recognise early,
              explain honestly, get psychiatric input. Suspect when
                      - spells situational or induced by suggestion
                      - thrashing, variable MMs, or "swooning", unlike true
                          seizures
                      - avoidance behaviour (resists eye opening or airway
                          occlusion) despite no responses to pain
                      - prolonged spells with vigorous movements but no
                          compromise to airway or vital signs, and abrupt recovery in
                          responsiveness
              Self harm (exc. bruising), hypersalivation or incontinence rare.

3)     SLEEP DISORDERS (parasomnias). Not all are fully described - difficult to
       study properly. Most often confused with epilepsy are:
              h Terrors - nature of behaviour is a clue - almost all within 1-3
                   hours of sleep onset ("before midnight") and single episodes in the
                   one night. Two or more in one night, incl. after midnight, suggests
                   epilepsy.
              • Sleep myoclonus (esp. neonate) - can be repetitive, almost
                  rhythmic, hence mistaken for seizures. Face usually uninvolved,
                  airway/respiration unaffected, cease when baby aroused.

4)     NEUROLOGIC EVENTS ie specific neurologic symptoms
       h      Episodic vertigo
       h      tics/dyskinesias
       h      migraine
       h      narcolepsy/cataplexy
       h      vascular
       Diagnosis from careful history and neurologic knowledge. Referral often
       needed.

                                         -12-
SEIZURES & NEUROLOGICAL EMERGENCIES                                          LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS

5)      FICTITIOUS EVENTS. The so-called Munchausen-by-proxy syndrome of
        child abuse (refer to Child Abuse section of curriculum). History of "seizures"
        is especially prone to fabrication - attacks also can be induced (ie suffocation,
        drugs). Usually a problem of early childhood.
        Clues include atypical/implausible history, frequent "spells" where enquiry
        reveals no one other than mother has witnessed, "resistant epilepsy" with
        repeatedly normal EEGs. Hospital admission plus Child Protection/Psychiatry
        Unit involvement essential.


             EPILEPSY – PRINCIPLES OF MANAGEMENT
     1. ISSUES FOR CHILD AND FAMILY
           • Disorder with many causes (often unknown – ‘idiopathic’/genetic),
             forms and outcomes. Tests and therapy vary case to case.
           • Anxiety from uncertainty – seizures usually unpredictable. A ‘hidden
             disability’.
           • Common fears (often not volunteered) include :
                     -brain damage from fits
                     -lifelong disability
                     -cause is birth injury or tumour
             These are usually unjustified. In the common ‘milder’ epilepsies, the
             good prognosis must be stressed.
           • Misconceptions and prejudices exist despite education and
             ‘information overload’.
           • The older child also has to cope with
                     -taking the drug(s)
                     -parental anxieties and possible overprotection
                     -effects on self esteem, peer relationships
                     -possibly restricted activities
                     -school issues
             As adolescence advances, issues of independence, driving, vocation,
             contraception may arise.
           • Support and information from the local Epilepsy Association can be
             valuable. Parents may need to discuss information obtained from the
             Internet.

     2. OPTIMAL MANAGEMENT
          • Information, repeated and reinforced.
          • Accurate diagnosis of epilepsy syndrome.
          • Continuity of medical care, with telephone contact available and GP
             involvement. Specialist input from paediatrician or child neurologist.
          • Various non-drug issues are important.

            SEIZURE FIRST AID – guidelines widely available, must be discussed in
            relation to type(s) of seizure experienced. Includes what not to do (put
            things in mouth, CPR, forcibly restrain), when to call ambulance (T/clonic
            type fit for >3-5 minutes, a second fit quickly follows, or child injured),
            what to do after fit ceases, (observe, let sleep, call doctor if in doubt).
            Basic airway protection in all cases. Always deal with ‘brain damage’
            issue – make clear that fits long enough to injure the brain are rare, and
                                          -13-
SEIZURES & NEUROLOGICAL EMERGENCIES                                         LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS

          that modern first aid guidelines allow large safety margin. Emergency
          rules need to be ‘simple’ but as a result may convey a wrong message.
          POSSIBLE SEIZURE PROVOCATIONS – in children, mainly febrile
          illness, over fatigue/lack of sleep, therapy mishaps, infrequently photic
          stimuli.
          KEEPING SEIZURE RECORD
          LIFESTYLE ISSUES – vary case to case
              climbing
              water
              bathroom
              riding
              driving
              Medic Alert bracelet?
          SCHOOL ISSUES
          IN SEVERE/REFRACTORY CASES – often with other handicap, ie.
          mental delay – head protection (helmet), special schooling etc.

   3. ANTIEPILEPTIC DRUGS (AED’s)
      As of 2004, Australian PBS listing consists of:
       (a) ‘ESTABLISHED’ (unrestricted) AED’s
                valproate(VPA)
                carbamazepine(CBZ)
               phenytoin(DPH)
                barbiturates (phenobarbitone, primidone)
               benzodiazepines(BZD)
                ethosuximide(ESM)
               acetazolamide, sulthiame, corticosteroids
      (b) ‘NEW’ (PBS authority listed) AED
               lamotrigine(LTG)
               topiramate(TPR)
               vigabatrin(VGB)
               gabapentin(GBP)
               tiagabine(TIA)
               oxcarbazepine
               levetiracetam

       Those marked are most common first-line AED’s in children, depending on
       seizure type and age.
       A general guide to spectrum of action of AED’s is:
               • GENERALISED and FOCAL Sz -valproate
                                                       -some BZD
                                                       -lamotrigine
                                                       +topiramate
               • ABSENCE + MYOCLONIC Sz ONLY – ethosuximide
               • FOCAL Sz (and some generalised T/C Sz) – the rest
       Corticosteroids and the ketogenic diet have specialised indications.
       Neurosurgery (mainly in specialised referral centres) is valuable for some
       refractory cases, especially with focal epilepsy. Vagal nerve stimulation is a
       recent, specialised, partly experimental technique.



                                         -14-
SEIZURES & NEUROLOGICAL EMERGENCIES                                     LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS

       BASIC ASPECTS OF AED USE
            • Phase-in is gradual to minimise side effects, except in emergencies.
               Given twice daily (with food), TDS dosing seldom necessary.
               Tablet forms preferred whenever child old enough.
            • Optimal dose is not a standard mg/kg/day – rather the lowest that
               gives maximal benefit without side effects, for that child. Mild
               epilepsy may do well on low dose, severe cases may need maximal
               tolerated doses.
            • Possible mishaps – dose missed, illness, seizure relapse – and what
               to do, are discussed.
            • Drug changes often required, for side effects or inadequate
               response, parents should be prewarned of this.
            • AED withdrawal, after adequate seizure-free period (often 1-4
               years, varying with syndrome and other factors) is gradual, over 2-
               4 months in most cases.
            • Side effects – assessed clinically. Parents informed, told to report
               symptoms promptly. Doctor must do his homework. Most
               frequent are ‘neurotoxic’ SE’s (sedation, behavioural, non-specific
               ie. headache, ataxia), occur with any AED, not always dose related,
               some children very susceptible. Gastrointestinal SE’s especially
               CBZ,VPA,ESM. Skin allergy mainly CBZ, LTG, barbiturates.
               Severe idiosyncratic (liver, bone marrow) rare (< 1/20,000 –
               1/40,000), not predicted by doing routine blood tests. Some AED’s
               have very specific toxicity which Doctor must be aware of.
               Possible teratogenicity may be an issue.
            • Plasma level (PL) tests – often overused. Should not be routine,
               but to help answer specific problems, ie. poor seizure control,
               possible side effects, drug interactions, altered drug metabolism.
               Available for most established AED’s but not new agents (exc.
               LTG). The ‘therapeutic range’ not relevant to all patients – as for
               drug doses, mild cases may need less, severe ones more – don’t
               change dose without a clinical reason. Relation between PL and
               drug effect poor for VPA, BZD, barbiturate, LTG. PL’s most
               useful to adjust phenytoin dose. Best time to do test varies – if
               seizure relapse, PL after fit or a trough – if possible toxicity, PL
               when symptoms occur or a peak level is ideal. Further reading –
               Current Therapeutics (Australia) September 2001 p. 9-13 review by
               F. Vajda.

   4. SPECIAL SITUATIONS
           • ISOLATED (self-limited) SEIZURE PROBLEMS common in
              kids, ie. most neonatal Sz, febrile Sz, post-trauma, metabolic /
              inflammatory brain disorders, drug side effects. A subtle genetic
              tendency may coexist. Emergency drug therapy may be needed,
              not normally chronic treatment. Mild syndromes, especially
              benign focal epilepsy, may not warrant daily drug therapy, after
              discussion of the issues with family.
           • EMERGENCY DRUGS FOR HOME USE ? Rectal diazepam or
              nasal/buccal midazolam, may terminate a potentially prolonged
              T/clonic type fit. Efficacy may be similar but this is not yet
              (c.2004) proven in large trials. When to provide has been debated
                                       -15-
     SEIZURES & NEUROLOGICAL EMERGENCIES                                         LECTURE 4
     DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS

                        since overuse by anxious parents can be problematic, risk of
                        prolonged Sz usually very low, and emergency care usually quickly
                        available. Severe CNS depression (ie. respiratory) is very unusual
                        with recommended dosage. Full instruction including when to give
                        (at once or wait 3-5min.) is essential. May consider when
                                     past history of prolonged fit(s)
                                     living remote from medical care
                                     previous seizure clusters (ie. groups of frequently
                                    repeated fits).
                        For drug dosages see EMERGENCIES – PROLONGED
                        SEIZURES. An initial test dose under medical/nursing supervision
                        is often advised, in case child has excessive sedative response.
                        Rectal diazepam given from IV ampoule (2ml, 5mg/ml) or ‘kit’
                        prepared by some hospitals, using small syringe / plastic feeding
                        tube / lubricant. Midazolam is dripped into anterior nares or buccal
                        cavity, from ampoule (1mg or 5mg/ml). Maximum recommended
                        doses for parent use are – diazepam 10mg, midazolam 5mg.

B)   PAEDIATRIC NEUROLOGIC EMERGENCIES:
                       PROLONGED SEIZURES (T/CLONIC TYPE)

     • "STATUS EPILEPTICUS" - > 30 minute duration continuous seizure or
       episodic fits without neurologic recovery. The duration arose from baboon
       experiments indicating increased brain damage risk after 30 minutes. A
       traditional term but impractical clinically. Factors relevant to brain injury are:
                  "systemic" - hypoxia, hypotension, acidosis, hyperthermia
                  hypoglycaemia. The most critical.
                  "local" - high lactate levels, reduced substrate to brain, neurotransmitter
                  toxicity - possible "metabolic" injury to brain, can be seen on CT/MRI
                  scan as "oedema" or as severely depressed EEG activity.
                  brain damage seems rare in fits under 30 minutes, much longer ones may
                  cause no definite injury - much depends on severity of "systemic"
                  factors.
                  global or focal (esp. mesial temporal) injury may occur, sequelae range
                  from later focal epilepsy (esp. TLE) to severe mental/physical handicap.
                  critical time for damage unknown for any individual child, and exact
                  seizure duration seldom determined from history.
                  longer fits may be less drug-responsive.
     • "PROLONGED SEIZURE" - pragmatic concept - clinical experience including
       monitored GTC fits shows that convulsive phase duration seldom >2 minutes.
       DRUG THERAPY advised after 3-5 minutes or if fits rapidly recur (may be
       prelude to continuous status). In practice, if fit is ongoing at presentation, assume
       it is prolonged.
     • PROLONGED FITS IN KIDS - most of these are:
       - febrile or of unknown cause
       - in first 3-5 years of life
       - the child's first ever attack
       Those due to acute brain disease (ie. meningitis) or chronic CNS handicap, have
       higher morbidity. Asymmetric (or unilateral) fits are frequent. CNS motor
       conduction fails, and muscles fatigue, the longer the fit, most often in the very
                                               -16-
SEIZURES & NEUROLOGICAL EMERGENCIES                                         LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS

   young - motor activity decreases, child unconscious with abnormal eye
   movements/muscle twitches/unstable vital signs - this is late, dangerous status,
   though fit seems "milder" in physical terms.

TREATMENT
1) FIRST AID, AIRWAY, RESPIRATION. Usual principles. Suction + mask
   oxygen if available. Get help. Assist ventilation if seriously compromised
   despite airway care.

2) IV ACCESS. Do blood glucose, treat if low. If circulation/BP adequate, do not
   infuse IV fluids rapidly (can promote brain oedema). If IV access difficult, start
   AED therapy by alternate route (see 3).

3) INITIAL DRUG THERAPY. Optimal is IV BZD, we prefer DIAZEPAM (0.2-
   0.3mg/kg over 1-2 minutes. Estimate for infants is - age in years +1mg).
   Apnoea/hypoventilation may need bag/mask assistance. If no quick IV access -
   DIAZEPAM RECTAL 0.5mg/kg - alternative is MIDAZOLAM IMI or
   intranasal, 0.2-0.3mg/kg (duration of action probably shorter, not yet proven
   superior by large trials). All BZDs for use in Australia have short action (go to
   fat stores, blood levels drop quickly within 1/2 hour) - fit may recur, consider
   follow-up drug (see 5). With rectal, IMI or nasal route, response should be within
   10 minutes. Meanwhile, secure an IV or get more experienced help.

4) FIT CONTINUES? - notify ICU/anaesthetist if available. Prepare
   airway/ventilation support. Oximetry and ECG where available.
   DRUG CHOICE varies with:
                           -     who / where you are
                           -      help available, and
                           -      urgency of "ABC" issues
   Either IV AED (phenobarbitone, phenytoin - dose 15-20mg/kg as 10-15 minute
   infusion - check ECG with phenytoin, sedation with phenobarb) or anaesthetic
   agent (IV thiopentone 1-2mg/kg or other - watch BP/ventilation - will need
   follow-up drug). Ongoing treatment is an ICU issue - support, monitoring, other
   drugs(s) - beyond scope of these notes.

5) FOLLOW-UP DRUG? See 3 above. Seizure relapse after BZD therapy a
   greater risk if febrile illness, acute or chronic brain disorder or previous
   prolonged fit(s). Always consider adding longer-acting AED (usually phenobarb
   or phenytoin, after loading dose). Get specialist paediatric advice if in any doubt.

6) CONSIDER CAUSE. Immediate blood glucose check. Take BP after fit ceases.
   Was fit part of an encephalopathic illness? ie. febrile (?meningitis) or other - what
   were symptom(s) before the fit? Consider AED plasma level if child on chronic
   therapy.

7) ASSESS RECOVERY. Marked sedation from acute BZD therapy alone is brief,
   10-30 minutes. If doesn't recover as expected, consider:
                              - ongoing seizure state ("masked status")
                              - brain swelling from status
                              - serious underlying cause
    Prompt advice, investigation (?CT ?EEG) and possibly intensive care are
    required.
                                          -17-
SEIZURES & NEUROLOGICAL EMERGENCIES                                       LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS



          ACUTE BRAIN DISEASE (ENCEPHALOPATHY)

Emergency treatment and search for cause are often concurrent. It is essential that
       serious treatable causes are quickly recognised (ie. infections,
       hypoglycaemia, neurosurgical disorders).
       the potential for rapid neurologic deterioration is remembered (often due to
       seizure or raised intracranial pressure).


HISTORY Onset over minutes to hours consistent with trauma, asphyxia, seizures,
vascular event and some toxic causes. Onset over days more typical of infection,
metabolic, systemic disease
              Type of symptoms varies and is diagnostically helpful, ie.
                       febrile illness +CNS symptoms
                       progressive loss of consciousness alone
                       confusional state
                       sudden seizure(s)
                       acute headache deterioration
                       stroke-like focal deficit, ie. hemiparesis, ataxia
Infant's symptoms less specific, including poor feeding, lethargy, vomiting, hypotonia
- most can be early sign of raised ICP.
              Past/family/social history - possible clues to neglect (?NAI), genetic/
              metabolic disease, toxic/drug exposure, atypical infection.


EXAMINATION: Attend urgently to vital signs
                                      injury
                                      ongoing seizure
                                      brain herniation
then general and neurologic examinations in detail.


BASIC NEUROLOGICAL EXAMINATION:
          conscious state -GCS or other
          head, fontanelle ?meningism
          optic fundi, pupils, eye movements
          motor/reflex cranial nerve function
          motor response, reflexes, ? focal signs

CAUSES. Some things common in adults (ie. strokes, substance abuse) are much
less so in kids - while problems like NAI and metabolic disease are frequently
considered in the very young. Neonates have particular spectrum of causes, ie.
asphyxia, brain haemorrhage, infections etc.




                                         -18-
SEIZURES & NEUROLOGICAL EMERGENCIES                                        LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS


MOST FREQUENT                                     LESS OFTEN
 Trauma including NAI                              Metabolic
 Infective disease                                  - glucose, electrolyte
   - meningo-encephalitis                           - genetic disorders
   - abscess, empyema                              Toxic - drugs
   - immune type encephalitis                              - lead
 Seizures including non convulsive status                  - venoms
 Hypoxia / ischaemia                               Vascular
   - asphyxia incl. NAI                             - bleeding (subdural intra-
   - hypotension                                          cerebral-AVM)
                                                    - stroke
                                                    - hypertension
                                                    - migraine
                                                   Systemic disease
   Case histories will be reviewed                  - infections
                                                    - organ failure
   Accidental head injury (and its complications)   - malignancy etc.
   is not considered here                          Raised ICP
                                                    - shunt block
                                                    - hydrocephalus

RAISED INTRACRANIAL PRESSURE (ICP). Consider a possible factor with
almost any primary cause - and whenever there is coma, neurologic deterioration or
certain key signs (see below). May result from mass lesion, cerebral oedema or
hydrocephalus. May be worsened by treatable factors - fits, excess IV fluid,
hypoventilation (raised pCO2) increased CVP. Ill-advised lumbar puncture may
precipitate brain shift (coning).
• Key signs of brain shift (any one or more)
            - progressive coma
            - dilated poorly reactive pupil(s)
            - eye deviation down or laterally
            - irregular / depressed respiration, bradycardia (CRITICAL)
            - Extensor posturing limbs or trunk
         Absent reflex (Dolls eye) eye movements can be drug or metabolic effect as
         well as from coning. Papilloedema not seen if ICP is acutely raised (takes
         time) - but retinal haemorrhages may mean subdural bleed with raised ICP..
         Extensor posturing may look like a fit but suspect coning if coma preceded
         posturing, pupil(s) are dilated or marked bradycardia. CT/MRI may seem
         normal (no obvious lesion) with cerebral oedema, despite raised ICP.
         Clinical signs are the most useful.


INVESTIGATIONS. May be extensive, as diagnosis often unclear initially.
• blood/urine tests incl. cultures, toxicology
• CT + MRI scan
• EEG
• metabolic tests for (genetic) "inborn errors"
• CSF exam - if infection diagnosis is critical (ie. possible meningitis) and clinical
   state permits (NOT if coma, ongoing seizures or sign(s) consistent with brain
   shift). Always consult experienced person - CT scan first if any doubt. Antibiotic
   and ICU therapy before lumbar puncture, may be the safe option.

                                         -19-
SEIZURES & NEUROLOGICAL EMERGENCIES                                       LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS


MANAGEMENT
• EMERGENCY MEASURES           resuscitation
                                    -
                               seizure Rx
                                    -
                              for hypoglycaemia
                                    -
                               trauma
                                    -
                              for brain shift (hyperventilation, IV mannitol
                                    -
                              infusion 0.25-0.5g/kg, notify
                              neurosurgeon/neurologist)
•   CLOSE OBSERVATION - SUPPORTIVE CARE
•   SPECIFIC MEDICAL THERAPY
                           - anti-epileptic
                           - antibiotic
                           - acyclovir (?herpes encephalitis)
                           - for specific intoxication, systemic disease
                           - for metabolic disorders
•   NEUROSURGICAL          - trauma
                           - haematoma (cerebral, subdural)
                           - abscess, empyema
                           - hydrocephalus
                           - shunt obstruction
                           - ICP monitoring
•   INTENSIVE CARE ISSUES


            ACUTE WEAKNESS/SPINAL CORD LESIONS

1) NEUROMUSCULAR DISORDERS. Most cause bilateral, symmetric weakness.
    • polyneuritis (GB syndrome)
    • infant botulism (first 6 months of life)
    • acute myositis (often more pain than weakness)
    Other causes much less common
   - focal (polio-like)
   - toxic neuropathy
   - myasthenia
   - auto-immune muscle disease (dermatomyositis)
    Signs - flaccid weakness, hypo- or arreflexia, variable cranial nerve weakness,
    less often sensory signs (mostly muscle-type pain).
    Action          hospitalise if weakness bilateral or any other concern
                    detect bulbar weakness and respiratory involvement early - need
                    for INTENSIVE CARE is highest priority.
Danger signs can evolve in hours. Assessing the under 5 year old is difficult, needs
    close observation and oximetry. Be very watchful if weakness involves upper
    trunk or arms.
                        excess secretions, poor voice/swallow
                        restlessness, resting tachycardia
                        poor cough / chest expansion
                        oximetry
                        serial VFTs in older child
    Polyneuritis (GBS) is the single most common cause - tests and therapy similar to
    adults - severe cases given IV immunoglobulin which may shorten duration of
    weakness.

                                        -20-
SEIZURES & NEUROLOGICAL EMERGENCIES                                        LECTURE 4
DR. J.I. MANSON & DR. K.J. ABBOTT, PAEDIATRIC NEUROLOGISTS

2) ACUTE SPINAL CORD DISORDERS
   • CAUSING CORD COMPRESSION                         abscess
                                                      tumour
                                                      haematoma
                                                      vertebral disease
    •   INFLAMMATORY myelitis
    •   VASCULAR
    •   TRAUMATIC
    Greatest urgency is compression - rapid, irreversible damage if undetected early.
    Must be excluded as urgent priority whenever acute spinal cord syndrome
    suspected - best by spinal MRI scan.
    UNEXPLAINED BACK OR NECK PAIN the most useful early sign - often
    persistent and severe - if increasing, present at night or with fever, has extra
    urgency. "Never" functional in children. With this, may be STIFFNESS,
    RELUCTANCE TO MOVE TRUNK, or ABNORMAL POSTURE (ie.
    torticollis). Always get expert advice incl. neurosurgical expertise. When severe
    weakness or urinary retention also present, situation is critical.
    Tests such as plain x-rays, CT spine and bone scan are inadequate, must not delay
    MRI. Lumbar puncture contraindicated.
    Non-surgical disorders (myelitis, GBS, discitis) can cause prominent spinal
    discomfort, but cord compression more-often-than-not cannot be excluded
    without MRI.
    Neurologic signs of cord disease may be hard to confirm in a fearful young child
    in pain, who resents movement. Abnormal gait is earliest sign in ambulant child.
    A motor level (weakness in legs only, or arms + legs with normal function
    above), reflex changes (can be increased or reduced + extensor plantar
    responses), or sphincter dysfunction are most useful. Sensory loss (ie. sensory
    "level" on trunk) hard to verify in many children, too late and unreliable to be
    depended on.




For those interested to read further, the following articles are available in the WCH
Library:
         Archives of Disease in Childhood
                 vol. 79 p.73-77, 1998 - Status Epilepticus
                 vol. 79 p.78-83, 1998 - Treatment of Acute Seizures
                 vol. 85 p.303-312, 2001 - Non traumatic coma
         Journal of Paediatrics and Child Health
                 vol. 36 p.208-212, 2000 - Persistent or severe back pain
         Developmental Medicine & Child Neurology
                 vol. 41 p.207-210, 1999 - Convulsive status (note - lorazepam for IV
               use not marketed in Australia)
         Practical Paediatrics, 5th Edition 2003
                 p.544-552 -Seizures and epilepsies Harvey, AS.
                Eds Robinson & Roberton/Churchill Livingston


J.I. MANSON                                                  KJ ABBOTT
JANUARY 2004
H:/MANSON/LECTURE 4 CONVULSIVE DISORDERS IN CHILDHOOD.doc



                                           -21-

				
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