Coma-producing brain lesions that result from trauma include subdural and epidural hematomas, intraparenchymal and subarachnoid hemorrhage, penetrating injuries, cerebral contusion, diffuse cerebral edema, and concussion (see Chapter 113 Neurotrauma ) Though most pediatric head injuries are blunt in nature and are accompanied by a history of trauma, nonaccidental head trauma is also common and may present with nonspecific complaints and deliberately inaccurate histories Patients suffering head trauma may present in a comatose state or may be alert for variable periods after impact ALOC resulting from diffuse cerebral edema and diffuse axonal injury is common in children and is less amenable to neurosurgical intervention than focal lesions such as epidural and subdural hematomas Characteristic loss of gray– white interface on CT may not be visible for 12 to 24 hours after injury When diffuse radiographic abnormalities appear, they may resemble those produced by hypoxic/ischemic insult Concussion is an inexact term for a transient alteration in normal neurologic function after head trauma Postconcussion syndrome is characterized by variable combinations of physical symptoms (e.g., nausea, vomiting, dizziness, headache), behavioral changes (e.g., irritability), sleep disturbances, and cognitive dysfunction, with symptoms lasting weeks in some patients Neuroimaging studies are normal in concussion, yet patients may be ill enough to require admission for observation, analgesia, and intravenous (IV) hydration Seizures Consciousness is greatly diminished during and after periods of seizure activity Generalized seizure activity is readily recognizable by rhythmic motor activity accompanying ALOC Partial or absence seizure activity may present more subtly with staring, tremors, eye blinking, rhythmic nodding, or other repetitive motor activity Seizures of all types, except absence and simple partial seizures, are usually followed by a postictal period, during which obtunded patients gradually regain consciousness Patients in nonconvulsive status epilepticus may present in coma, and if other causes have been ruled out, comatose patients should have an electroencephalogram (EEG) performed The diagnostic approach toward a patient with ALOC from seizure activity varies based on whether seizures have occurred in the past and the progression or resolution of his or her neurologic abnormalities (see Chapter 72 Seizures ) Posttraumatic or new focal seizures are assumed to reflect an intracranial lesion until proven otherwise Children taking antiepileptic medications benefit from drug-level measurement (if available for the medication) during an observation