CT BRAIN

Introduction

Guidelines are for general guidance but do not replace the responsibility of the clinician to decide on the optimal treatment for each individual patient.
When doubt or disagreement exists on the urgency of investigations advice should be sought from consultant emergency medicine, radiology and other specialty staff as appropriate. This is the responsibility of the emergency physician. It should not be routine.
If the ED is at 100% occupancy an investigation that may allow us to admit, transfer or discharge a patient may be performed despite lower clinical urgency.
Procedural delay – if it’s agreed that a scan should take place that evening it may be appropriate to allow a delay of several hours to perform several scans at the same time.
Disposition of patients has to be considered. If investigations are delayed then we must have agreement from the relevant specialties that admission will take place prior to investigations.

CLICK BELOW FOR MORE INFORMATION ON EACH CONDITION

Unexplained sudden headache (meningitis not suspected)

Suspected Meningitis

Head Trauma

Head Trauma / Anticoagulation

Stroke

Shunt complications

Unexplained sudden headache (meningitis not suspected)

GCS 15: no focal neurology

C.T. within 12 hours of onset of symptoms
Perform up to 24.00 out of hours (if 12 hour limit expires before 8 am)
If symptoms present for greater than 24 hours scan may be delayed till 8 am
If patient waiting overnight for investigation then admit under neurology
If deterioration then immediate C.T.

GCS < 15, focal neurology

C.T. on presentation

Suspected Meningitis

GCS 15: no focal neurology, normal mental state

LP without prior C.T.

GCS <15 / focal neurology / Altered mental state

Empirical antibiotics prior to C.T.
Delayed LP
C.T. to exclude abscess / other causes if clinically suspected

Head Trauma

C.T. indicated if (any one present).

GCS < 14
GCS 14 noted on 2 obserations 30 mins apart (with senior MO r/v of patient)
Suspected open or depressed skull #
Vomiting ³ 2 episodes
Amnesia before impact > 30 mins

Head Trauma / Anticoagulation

C.T. indicated if (any one present).

Moderate risk - any duration LOC / vomiting / headache / focal signs / drowsiness / any GCS

C.T. - Any evidence of blood

Reverse

Admit all

C.T. - normal

Consider reversal of anticoagulation depending on reason for anticoagulation

C.T. not indicated

Low risk - ° LOC / vomiting / focal signs / drowsiness / GCS 15
Observe / admit

Stroke

C.T. indicated in

Possible thrombolysis (within 2 1/2 hours)
Patients on anti-coagulants
Suspected basilar/vertebral artery occlusion within 12 hours
Posterior fossa / cerebellar signs in patients suitable for surgery
Crescendo TIA's on aspirin
"Stroke in evolution"

Shunt

Urgent

GCS <15 / fits / septic

Discuss with neurosurgeons prior to C.T.

Sub-acute - Perform C.T. up to 24.00 out of hours

If symptoms present for greater than 24 hours scan may be delayed till 8 am

If doubt according to urgency discuss with neurosurgeons

Revised 5 July 2002

Dr Tom Soulsby, Dr Roger Davies, Margaret Crockford, Dr Alphonse Roex

REFERENCES

The guidelines have been prepared from relevant background literature and discussions between Emergency Medicine and Radiology staff.
Systematic reviews have not been performed but were included if available from available literature.

Edlow, J.A. Making the diagnosis of SAH. Journal Irish Colleges Physicians / Surgeons 2002, 31(1): 32-36

Hasbun R, et al. C.T. of the head before L.P. in adults with suspected Meningitis, New England Journal of Medicine 2001:345 (24):1727 - 1733

Edlow JA, et al. Primary Care: Avoiding Pitfalls in the diagnosis of SAH. New England Journal of Medicine 2000; 342 (1): 29 - 36

Morgenstern LB,et al. Worst Headaches and SAH: Prospective, Modern Computerised Tomography and Spinal Fluid Analysis. Ann Emergency Med 1998: 32(3): 297 – 304

Canadian C.T. head rule for patients with minor head injury, Lancet 357 (9266); 5 May 2001.

Pre-injury warfarin does not impact outcome in trauma patients, Journal of Trauma Injury, Infection and Critical Care 51 (6): 1147-51

Garra G et al. Minor head trauma in anti-coagulated patients. Academic Emergency Medicine 6 (2): 121-4; Feb 1999

Tomlinson P. Complications in shunts with adults with spina bifida. BMJ 1995.311(7000)286-7

Watkins L. The diagnosis of blocked CSF shunts. Chids Nerv. Syst 1994.10:87-90