Median time to intracranial pressure monitoring is 3 hours in Traumatic brain injury in England and Wales 1).
1)
Lawrence T, Helmy A, Bouamra O, Woodford M, Lecky F, Hutchinson PJ. Traumatic
brain injury in England and Wales: prospective audit of epidemiology,
complications and standardised mortality. BMJ Open. 2016 Nov 24;6(11):e012197.
doi: 10.1136/bmjopen-2016-012197. PubMed PMID: 27884843.