The majority of seizures are of a short duration and self-limited; thus, little intervention is required. In most cases, pre-hospital personnel will arrive at least five minutes after the onset of seizure activity, such that patients who are still seizing on EMS arrival should be managed as presumed status epilepticus. If a patient is found convulsing or remains confused or unresponsive, paramedics should immediately measure the patient's blood sugar or, if this test is not available, they can empirically administer dextrose (D50).
There have been several studies that have investigated the safety and efficacy of benzodiazepines in the prehospital management of pediatric seizures. In a randomized double-blind out-of-hospital trial, Aldredge et al compared lorazepam, diazepam, and placebo administered intravenously by EMS personnel to patients with seizure activity lasting more than five minutes. The odds ratio for termination of seizure on arrival to ED in the lorazepam group compared to placebo was 4.8. For diazepam, it was 2.3, though this difference between diazepam and lorazepam did not achieve statistical significance. Interestingly, the rates of respiratory and circulatory complications were significantly worse in the placebo group compared to either benzodiazepine group. Not only does this confirm the safety of out-of-hospital benzodiazepine use, but it suggests the danger of untreated and prolonged seizure activity.22
When IV access is not immediately available, rectal diazepam is an option. 37, 38 One prospective study reported that there were no significant differences between rectal and intravenous diazepam therapy with regard to SE duration, intubation, or recurrent seizures in the emergency department. These data suggest that prehospital administration of diazepam may shorten the duration of SE in children and simplify the subsequent management.
In a retrospective study on prehospital seizure management in children, rectal diazepam .5 mg/kg, was compared to IM midazolam, .15 mg /kg. Over the four year study period, 2566 children presented with seizures and 107 children were eligible for entry into the study. Of these 107 patients, 62 received diazepam and 45 received midazolam. Both groups were similar in terms of demographics and seizure type. Both drugs were effective in stopping seizures within five minutes of drug administration; however, fewer patients in the midazolam group suffered apnea.7 In a study comparing IV diazepam to IM midazolam, Chamberlain et al concluded that IM midazolam is an effective anticonvulsant for children with motor seizures and an important alternative when IV access is not easily available. Vilke et al compared IM to IV midazolam and reported that IV delivery was more effective: 47/49 in the IV group vs 20/25 with IM administration (p less than 0.05). Four patients (three treated IM and one IV) had respiratory compromise necessitating field airway management.
In light of the Chamberlain and Vilke studies, some experts recommend IV midazolam as the agent of choice in the prehospital management of seizures. In some paramedic systems, patients who are "found down" and seizing are routinely transported to the ED in spinal precautions. One large retrospective study suggests that this may be unnecessary. In a review of 1656 patients with seizures not associated with major trauma, no patient had a concomitant spinal fracture. 39 Regarding level of transport, asymptomatic patients who have had a seizure can be transported by an EMS unit if the transport time is short in that it is unlikely that this group of patients will experience a second event during transport.40
Patients with a known seizure disorder who experience a "typical" event and are asymptomatic afterwards do not necessarily require transport to the hospital if they are competent to refuse transport. However, medics should advise these patients to contact their primary care provider as soon as possible.