Dr Hector Thomson
Peer review: Dr Luke Phillips
Editor: Dr David McCreary
Back to the case…
The nurse tells you the left pupil is now fixed and dilated. The blood pressure is 190/110 and the HR is 40. What do you do now? The patient desperately needs a CT scan of their brain and a neurosurgeon but there are steps you can take to temporise the situation. Good care of neurologically injured patients requires a focus on doing the basics well and preventing secondary brain injury.
This is the extreme end of raised ICP management. The Neurocritical Care Society has a tier system that lends itself well to a structured exam answer.
- Elevate head to 30 degrees + Keep head midline/Loosen ties and collar
- Hyperventilate at 20 breaths per minute aiming for EtCO2 of 30mmHg and keep SpO2 94-98%
- Send an ABG
- Avoid high PEEP
- Osmolar therapy: Mannitol or Hypertonic saline
- Mannitol 20% = 0.5-1g/kg or 2.5ml/kg over 10 minutes -> Practically, this is 100-200ml
- Place IDC + Replace losses with normal saline
- 3% hypertonic 250ml over 10 minutes
- Get the systolic above 110mmHg to defend the cerebral perfusion pressure (CCP = MAP – ICP) –> use Noradrenaline if necessary
- Deeply sedate +/- Paralyse = Propofol or Midazolam + Analgesia (Fentanyl or Morphine)/Thiopentone bolus 250-500mg IV could be considered but this is more useful in the ICU when you have some form of ICP monitoring.
- Organise urgent CT Brain
- Call a neurosurgeon immediately
What are the indications to call a neurosurgeon?
- Skull fracture and confusion, decreased level of consciousness, epilepsy or any other neurological symptoms or signs
- Coma (GCS <9) continues after resuscitation
- Deterioration in neurological status such as worsening in conscious state (>2 points on GCS)
- Increasing headache or new CNS signs
- Confusion or other neurological disturbance (GCS 9–13) after > 2 hours with no fracture
- Open depressed skull fracture
- Suspected base of skull fracture such as blood and/or clear fluid from nose or ear, periorbital haematoma or mastoid bruising
- Penetrating injury – known or suspected
- An abnormal finding on CT Scan – Minor focal contusions or subarachnoid haemorrhage increases the risk of later deterioration but after consultation with the neurosurgical service may be managed on site
Or if you are in the middle of nowhere and they have an extradural requiring immediate evacuation due to logistical or patient factors then the College of Surgeons and the Australasian Neurosurgical society have excellent guidelines on how to perform a resuscitative craniotomy.
🤓 Ed: If you’re interested, this is one of the life and limb saving procedures we teach on The Procedures Course!
A legendary case performed by our neurosurgery and trauma teams at the roadside is described here.
The CT reveals a large extradural. You hyperventilate, start the mannitol and wheel him to theatre where the neurosurgeons are waiting to evacuate the clot. After weeks in ICU he slowly started to make purposeful movements. After a long stint at the ABI rehab unit he is reunited with his family at home.
5 KEY TAKEHOME POINTS FROM PARTS 1 & 2
- Small shifts in intracerebral volume may cause large differences in the intracranial pressure
- Subfalcine herniation: cingulate gyrus sneaking under the falx causing ACA stroke and hydrocephalus
- Transtentorial herniation: uncinate process squishes the midbrain causing ipsilateral dilated non-reactive pupil then motor weakness and coma
- Tonsillar herniation: fear the posterior fossa -> Cushing’s reflex of irregular breathing, bradycardia and hypertension
- Sit them up, ventilate to a CO2 of 30mmHg, get their SBP above 110mmHg, start a big bag of Mannitol then get them through a CT scanner and to a neurosurgeon
References / Resources
- Internet Book of Critical Care: Raised ICP – detailed notes on all things raised ICP by Josh Forkas
- Anatomy for Emergency Medicine: Brain Herniation – if you do nothing else, watch Andy Neill’s video on the anatomy of brain herniation (and all of his other videos while you’re there)
- Life in the Fast Lane: Brain Herniation
- Radiopedia: Brain Herniation
- Traumatic Victoria Guidelines
- Carney N, Totten A, O’Reilly C, et al. Guidelines for the Management of Severe Traumatic Brain Injury, Fourth Edition. Neurosurgery. 2017;80(1):6-15. PubMed
- Cadena R, Shoykhet M, Ratcliff JJ. Emergency Neurological Life Support: Intracranial Hypertension and Herniation. Neurocrit Care. 2017 Sep;27(Suppl 1):82-88. doi: 10.1007/s12028-017-0454-z. PMID: 28913634.
- Newcombe R, Merry G. The management of acute neurotrauma in rural and remote locations: A set of guidelines for the care of head and spinal injuries. J Clin Neurosci. 1999 Jan;6(1):85-93. doi: 10.1054/jocn.1997.0188. PMID: 10833574.
- Warner KJ, Cuschieri J, Garland B, Carlbom D, Baker D, Copass MK, Jurkovich GJ, Bulger EM. The utility of early end-tidal capnography in monitoring ventilation status after severe injury. J Trauma. 2009 Jan;66(1):26-31. doi: 10.1097/TA.0b013e3181957a25. PMID: 19131802.
- Tadevosyan A, Kornbluth J. Brain Herniation and Intracranial Hypertension. Neurol Clin. 2021 May;39(2):293-318. doi: 10.1016/j.ncl.2021.02.005. Epub 2021 Mar 31. PMID: 33896520.
- Knight J, De Jesus O. Tonsillar Herniation. [Updated 2021 Aug 30]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK562170/