What are the CT head requirements after a loss of consciousness and bu

Clinical answer with reasoning, red flags and references. Clinically reviewed by Dr Kola Tytler MBBS CertHE MBA MRCGP.

The indications for a computed tomography (CT) head scan following a loss of consciousness and head injury depend on age and clinical features.

For people under 16 who have sustained a head injury and have more than 1 risk factor, do a CT head scan within 1 hour of the risk factors being identified, such as loss of consciousness lasting more than 5 minutes (witnessed), abnormal drowsiness, 3 or more episodes of vomiting, dangerous mechanism of injury, amnesia lasting more than 5 minutes, or current bleeding or clotting disorder .
For people under 16 with only 1 risk factor, observe for at least 4 hours, and if during observation any of the following occur—GCS score less than 15, further vomiting, or abnormal drowsiness—perform a CT head scan within 1 hour .
For people 16 and over, do a CT head scan within 1 hour if they have a GCS score of 12 or less, suspected skull fracture, post-traumatic seizure, focal neurological deficit, or more than 1 episode of vomiting .
In people 16 and over who have had some loss of consciousness or amnesia, do a CT within 8 hours of injury if they are over 65, have bleeding or clotting disorders, a dangerous mechanism of injury, or retrograde amnesia of more than 30 minutes .

What are the CT head requirements after a loss of consciousness and bump to head