Duration and determinants of impaired consciousness after febrile status epilepticus in children.

PURPOSE: While prolonged impaired consciousness is often attributed to encephalopathy or meningitis, its occurrence and associated factors in patients with febrile status epilepticus without these conditions remain unclear. This study investigated the duration and determinants of impaired consciousness following febrile status epilepticus lasting ≥ 30 min in children treated with antiseizure medications.

METHODS

This retrospective multicenter study used data from the Febrile Acute Convulsion and Encephalopathy registry, a prospective multicenter consecutive case registry for acute encephalopathy and febrile convulsive status epilepticus in Japan. Children aged 6-60 months with febrile status epilepticus lasting ≥ 30 min who received antiseizure medication were analyzed. Clinical data and early laboratory results were compared between prolonged (≥4 h) and non-prolonged (<4 h) impaired consciousness groups.

RESULTS

Among 227 children with febrile status epilepticus lasting ≥ 30 min, the median time to recovery of consciousness was 176 min, and 79 (34.8%) had prolonged impaired consciousness (≥4 h). The two groups did not differ in age, sex, seizure duration, body temperature, history of febrile seizures, or number of antiseizure medications. Phenobarbital use was more frequent in the prolonged group. Laboratory abnormalities, including lower pH, lower base excess, higher creatinine, higher glucose, and higher ammonia were associated with prolonged impairment. Low pH was the only independent factor.

CONCLUSION

In children with febrile status epilepticus ≥ 30 min, prolonged unconsciousness (≥4 h) was associated with phenobarbital use and laboratory abnormalities, with acidosis as the sole independent predictor. Early recognition of delayed recovery may support timely clinical decision making and optimize emergency care.