Pediatric emergency medicine trisk 653

associated with tonic posturing The episode lasts only a few seconds, and afterward, the child resumes normal activity Acute dystonia, usually seen as a side effect of certain medications, can mimic a tonic seizure The child having a dystonic reaction, however, does not lose consciousness and has no postictal drowsiness Several paroxysmal events are associated with sleep Night terrors (see Chapter 126 Behavioral and Psychiatric Emergencies ) usually begin in the preschool years The sleeping child wakes suddenly, is confused and disoriented, and appears frightened, often screaming and showing signs of increased autonomic activity (tachycardia, tachypnea, sweating, dilated pupils) Such episodes typically last only a few minutes, and the child does not usually recall the event Benign myoclonus is characterized by self-limited episodes of sudden jerking of the extremities, usually upon falling asleep There is no alteration of consciousness In sleep paralysis, there is a transient inability to move during the transition between sleeping and waking, also with no change in the level of consciousness Pseudoseizures are occasionally seen, often in patients with an underlying seizure disorder or in patients who have a relative with epilepsy Some features suggestive of pseudoseizures are suggestibility; lack of coordination of movements; moaning or talking during the seizure; lack of incontinence, autonomic changes, or postictal drowsiness; response to painful stimuli; and poor response to treatment with anticonvulsant agents The most important diagnostic test in distinguishing nonepileptic events from seizures is a careful history, including a detailed description of the event from the person who witnessed it In atypical or unclear cases, referral for electroencephalogram (EEG) or video EEG monitoring may help in establishing the diagnosis Clinically, seizures may be divided into partial (also termed focal) and generalized seizures ( Table 97.2 ), and partial seizures are further classified as complex or simple Complex partial seizures imply impaired consciousness Generalized tonic–clonic seizures (previously called grand mal seizures ) are the type most often seen in acute pediatric care The onset of generalized tonic–clonic seizures is usually abrupt, although 20% to 30% of children may experience a sensory or motor aura If sitting or standing, the child falls to the ground The face becomes pale, the pupils dilate, the eyes deviate upward or to one side, and the muscles contract As the increased tone of the thoracic and abdominal muscles forces air through the glottis, a grunt or cry may be heard Incontinence of urine or stool is common After this brief tonic phase (10 to 30 seconds), clonic movements occur The child is unresponsive during the seizure and remains so postictally for a variable period After the seizure, there may be weakness or paralysis of one or more areas of the body (Todd paralysis) In atonic, or akinetic, seizures (drop attacks), there is abrupt loss of muscle tone and consciousness Myoclonic seizures are characterized by a sudden dropping of the head and flexion of the arms (jackknifing); however, extensor posturing may also occur The episodes occur quickly and frequently, as often as several hundred times daily TABLE 97.2 SEIZURE TYPES Generalized Partial (focal) Absence (petit mal) Typical Atypical Tonic–clonic (grand mal) Clonic Tonic Myoclonic Akinetic/atonic (drop attacks) Simple (no impaired consciousness) Motor Sensory Autonomic Psychic Complex (impaired consciousness) Partial seizures becoming partially generalized Absence (petit mal) seizures are generalized seizures, marked by sudden and brief loss of awareness, usually lasting to 30 seconds With typical absence seizures, there is no loss of posture or tone and no postictal confusion There may be a minor motor component such as eyelid blinking The child with simple partial (focal) seizures has unimpaired consciousness Motor signs are most common in children, although sensory, autonomic, and psychic manifestations are possible The motor activity usually involves the hands or face and spreads in a fixed pattern determined by the anatomic origin of the nerve fibers that innervate the various muscle groups Focal seizures may become secondarily generalized, in which case there will be alteration of consciousness Complex partial seizures, also called psychomotor or temporal lobe seizures, exhibit a diverse set of clinical features, including alterations of perception, thought, and sensation In children, they are usually marked by repetitive and complex movements with impaired consciousness and postictal drowsiness An important distinction is whether the seizure is associated with fever Simple febrile seizures are those that are single, brief (lasting less than 15 minutes), and generalized Approximately 20% of febrile seizures are complex, meaning they are focal, prolonged (last for more than 15 minutes), or have multiple episodes within 24 hours Triage and Initial Assessment For an actively seizing child, initiate immediate resuscitative measures and consider administration of antiepileptic agents, as discussed below After seizures have stopped, the first steps in the evaluation are a thorough history and a physical examination, the results of which are helpful in determining the direction of the search for a specific cause (see Table 72.1 and Fig 72.1 ) Important historical items to elicit include fever, trauma, underlying illnesses, current medications, and possible toxic ingestions A complete neurologic assessment to evaluate for signs of increased intracranial pressure (ICP), focal deficits, or signs of meningeal irritation is also essential Diagnostic Testing In children older than 12 months with a typical simple febrile seizure and no signs of meningitis, generally no further evaluation of the seizure is required However, lumbar puncture (LP) is indicated if meningitis is suspected on the basis of physical findings An LP should be considered in children younger than 12 months, in whom signs of meningitis may be subtle, such as irritability and poor feeding; when the febrile seizure is complex; or if there has been pretreatment with antibiotics In addition, LP should be considered for children with prolonged fever before the seizure, and for febrile children who not return to neurologic baseline quickly Other laboratory tests discussed in the next paragraph have been found to have little yield in the child with a typical febrile seizure and are unnecessary Appropriate diagnostic tests to determine the source of the fever are determined by other features such as the intensity of fever, immunization status, and the child’s age For the child who presents with a first-time, nonfebrile seizure, laboratory or radiologic evaluation to search for a specific treatable cause of the seizure may be indicated There is little utility in extensive, routine workups; rather, ancillary test selection should be guided by the results of the history and physical examination In young infants, children with prolonged seizures, and those with a suggestive history or physical examination, determination of serum glucose, sodium, and calcium levels are indicated Other ancillary tests that may be indicated, depending on the clinical picture, include serum magnesium, hepatic transaminases, ammonia, serum or urine toxicology tests, electrocardiogram (ECG), and neuroimaging of the brain LP is rarely emergently necessary in the afebrile child without meningeal signs or altered mental status, although it should be considered in neonates even without fever In children with a known seizure disorder, subtherapeutic anticonvulsant levels are the most common reason for breakthrough seizures The name and dosage of anticonvulsant medications used should be elicited, as well as the time of the last dose given, any missed doses, the last change in dosage, and recent levels, if known Intercurrent illness may also play a role because the metabolism of some medications is affected by systemic illness Such children should have blood drawn for measurement of anticonvulsant levels Although many drugs have a standard therapeutic range ( Table 97.3 ), individual patients may require levels outside that range for adequate seizure control; conversely, dose-dependent toxic effects may be observed in some children even at typically therapeutic levels Computed tomography (CT) (or magnetic resonance imaging [MRI], if available) is indicated in the emergency evaluation of prolonged or focal seizures, when focal deficits are present, when there is a history of trauma, when the child has a ventriculoperitoneal shunt, or when there are associated signs of increased ICP For other children with a normal neurologic examination, MRI may be useful in identifying structural anomalies and determining prognosis, but such studies may be deferred to a follow-up visit Cranial imaging is not indicated in the evaluation of simple febrile seizures EEG is also helpful in the evaluation of children with nonfebrile seizures EEG is rarely beneficial in acute management, but children with nonfebrile seizures should be referred for outpatient testing  ... Computed tomography (CT) (or magnetic resonance imaging [MRI], if available) is indicated in the emergency evaluation of prolonged or focal seizures, when focal deficits are present, when there