In the case of closed head injury, loss of consciousness may not be immediate; in fact, several minutes may elapse between the time of injury and the appearance of neurological signs.
To determine the state of consciousness, the Glasgow Coma Scale, through which a score of 8 or below determines severe trauma.
It is necessary to provide the patient with controlled ventilation and transfer him to intensive care unit.
Source: Mediserve‘s Medical Emergencies in Pediatrics.