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TABLE 72.2
DIFFERENTIAL DIAGNOSIS OF PAROXYSMAL EVENTS


Seizure disorders
Psychogenic nonepileptic seizures (Pseudoseizures)
Head trauma
Loss of consciousness
Posttraumatic seizures
Syncope
Hypovolemia
Hypoxia
Reduced cardiac output
Sleep disorders
Nightmares
Night terrors
Narcolepsy
Sleep apnea hypersomnia
Somnambulism
Apparent life-threatening event
Movement disorders
Paroxysmal choreoathetosis
Tic disorders
Shudder attacks
Benign myoclonus
Psychiatric disorders
Daydreaming
Attention-deficit hyperactivity disorder
Panic attacks
Gastrointestinal disorder
Sandifer syndrome (gastroesophageal reflux)

Abdominal migraines
Cyclic vomiting
Breath-holding spells
Pallid
Cyanotic
Atypical migraines


Psychogenic nonepileptic seizures (PNES) were formerly called
“pseudoseizures.” They are a movement disorder that resembles seizure activity,
but have no corresponding abnormal brain electrical activity. PNES include a
wide array of conditions ranging from conversion reaction to movement disorder
and even parasomnias. When the event is psychogenic in nature, the movements
can be quite startling, are typically bizarre and thrashing, and are often associated
with a great deal of vocalization. There is usually no biting, incontinence, or
injury associated with PNES. In contrast to seizures, PNES are rarely followed by
a postictal period or postictal headache, and patients often possess a clear mental
status after the event. PNES should also be suspected when the episodes are
almost always witnessed or heard and never during sleep, rather than occurring
randomly, and if the eyes are closed during the episodes (the eyes are closed in
less than 10% of actual seizures). In some cases, diagnosis may require long-term
video and electroencephalographic (EEG) monitoring. Further complicating the
issue is that PNES are most likely to occur in patients with an underlying seizure
disorder ( Table 72.2 ).
Breath-holding spells are common, affecting 4% to 5% of all children (see
Chapter 126 Behavioral and Psychiatric Emergencies ). They typically present
between the ages of 6 and 18 months and rarely persist past 5 years of age. The
two types of breath-holding spells—cyanotic and pallid—have common features,
including a period of apnea and an alteration in the state of consciousness.
Usually, some initiating event (e.g., pain, fear, agitation) triggers the episode. The

diagnosis is based on the clinical findings, and the prognosis is excellent.
A variety of movement disorders can also mimic seizures. Paroxysmal
choreoathetosis is often associated with a positive family history for seizures and
is exacerbated by intentional movement. Tic disorders can be manifested by
twitching, blinking, head shaking, or other repetitive motions. These are usually
suppressible and are not associated with any loss of consciousness. Shudder
attacks are whole-body tremors similar to essential tremor in adults. Benign
myoclonus of infancy can look like infantile spasms but is associated with a
completely normal EEG.
Sleep disorders, such as somnambulism, night terrors (preschool-aged
children), and narcolepsy (typically in adolescents) can often be diagnosed on the
basis of the history alone (see Chapter 126 Behavioral and Psychiatric
Emergencies ). Infants with gastroesophageal reflux may exhibit torticollis or
dystonic posturing (Sandifer syndrome). Atypical migraines and PNES are often
diagnosed after other causes are excluded.

INITIAL STABILIZATION


This section will focus on patients with generalized convulsive status. The first
priority in the seizing patient is to address airway, breathing, and circulation (see
Chapter 7 A General Approach to the Ill or Injured Child ). An adequate airway is
necessary to allow for effective ventilation and oxygenation. Patients with
impaired consciousness are at risk for obstruction (the tongue, oral secretions,
emesis), aspiration (loss of protective reflexes), and hypoventilation. Simple
maneuvers such as the jaw thrust or suctioning of the oropharynx may improve
the compromised airflow. The use of adjunctive airways (oral or nasopharyngeal)
may also help maintain an adequate airway. In patients who are actively seizing,
it may be difficult to insert these adjuncts and may cause injury if the intervention
is forced. Furthermore, in patients for whom trauma is a possibility, these

maneuvers must be undertaken with cervical spine (C-spine) immobilization. In
patients in whom the airway remains unstable despite these actions, endotracheal
intubation is warranted. When it is necessary to use a muscle relaxant to intubate
a seizing patient, one should use the shortest-acting agent possible. The presence
of motor activity may be the only clinical manifestation of seizure, and a longacting muscle relaxant will mask the ongoing seizure activity. One should
consider alternatives to succinylcholine in the setting of prolonged seizures
because of the potential risk of hyperkalemia related to rhabdomyolysis.
While securing the airway takes priority over other clinical assessment
elements, one will lose the ability to assess whether the clinical seizure activity
has stopped in a medically paralyzed child. Parameters such as heart rate are
notoriously unreliable. Missed “iatrogenic nonconvulsive status epilepticus” will
result in neuronal death despite lack of clonic or tonic features. The clinician must
consider interventions to avoid these dilemmas. For example, a patient may have
a potentially short-lived apneic episode following the rapid administration of a
benzodiazepine. When possible, such a drug should be administered over 1 to 2
minutes rather than rapid infusion, and short apneic/hypopneic episodes that may
follow can often be managed with a short period of bag–mask ventilation prior to
endotracheal intubation. If endotracheal intubation does take place, many
institutions offer an urgent limited-lead EEG that can help evaluating background
activity for possible ongoing seizure. If not available, an emergent EEG should be
obtained. Intubated patients often receive continuous infusions of a
benzodiazepine after endotracheal intubation to maintain sedation. However,
continuous infusions of benzodiazepines may also be used in the treatment of
refractory seizures. Aligning the dose of a benzodiazepine infusion with the latter
protocol may further mitigate the risk of ongoing “subclinical” seizure and
neuronal death.