Cranial Decompression (Burr Hole)

Last updated 16/10/17

Definition

• Emergency procedure of cranial decompression via burr hole for drainage of an acute extra-axial haematoma (epidural and/or subdural) in the neurologically deteriorating patient

Features

• Should only be undertaken by a competent practitioner after discussion with the receiving neurosurgical team and in accordance with the Neurosurgical Society of Australasia guidelines
• Mydriasis typically occurs on same side as haematoma
• In the absence of localisng signs
• Temporal 73%
• Frontal or subfrontal 11%
• Burr Hole Sites
• Temporal
• 1 finger breadth anterior to exteral auditory meatus
• 2 finger breadths supeior to zygomatic arch
• Approximate location of MCA (Middle Cerebellar Artery)
• Frontal
• 1 finger breadth anterior to coronal suture
• Coronal suture lies along perpendiular line from midpoint of lie between lateral canthus and external auditory meatus from one side to the other
• 3cm lateral to midline
• Approximately mid-pupillary line
• Parietal
• 2 finger breadths posterior to external auditory meatus
• 3 finger breadths suprior to mastoid process



Burr hole sites: superior view


Burr hole sites: lateral view

Indications

• Head inury with or without CT Brain confirmed epidural and/or subdural associated with significant neurological deterioration
• Unilateral mydriasis
• &/or reduction in GCS by 2 or more
• Discuss with neurosurgeon
• If < 2hrs from neurosurgeon transfer patient without burr hole
• If > 2hrs from neurosurgeon perform burrhole

Contraindications

• GCS >9 without neurolgical deterioration
• CT-Brain not available: unless discussed with neurosurgeon

Equipment

• Sterile gown, gloves, mask with visor
• Sterile field
• Sterile fenestrated drape
• Local Anaesthetic: Lignocaine 1% with Adrenaline
• Needles: 23G and 18G blunt
• Syringes: 10ml x2, 5ml x1
• Gauze x10
• Surgical marking pen
• Hair trimmer
• Chlorhexidine 2% in 70& Alcohol
• Suction catheter
• 2L warm normal saline 0.9%
• Instruments
• 1. Self-retaining retractor
• 2. Artery forceps
• 3. Forceps
• 4. Scalpel size 10
• 5. Scalpel size 11
• 6. Kerrison rongeurs (Bone nibblers)
• +/- 7. Periosteal elevator
• 8. Ruler
• 9. Hand held burr drill with 5mm bit and allen key
• 10. Venturi drain tubing





Burr Hole Equipment

Procedure

• Non Surgical Management of Icreased ICP
• Remove tight clothing around neck
• Mannitol 20% 1g/kg IV over 20 minutes
• Intubation with moderate hyperventilation
• EtCO2 to 30mmHg for 5-10 minutes
• Cease if signs resolve
• Optimise sedation and neuromuscular blockade
• Head up 30o if clinically appropriate
• CT Brain
• Must be performed prior to procedure if available
• Position
• Supine
• Assistant to hold head for entire procedure
• Burr Hole Craniotomy
  • Site selection
  • Mark out incision site
  • Temporal: start 1cm superior to zygomatic arch and draw vertically 3cm

  
  
  Marked out burr hole sites

  • Based on CT Brain
  • In absence of CT Brain or localising signs
  • Site may be indicated by
  • Palpable skull fracture with overlying scalp bogginess or injury; or skull fracture on x-ray
  • Mydriasis ipsilateral to haematoma
  • Temporal burr hole first
  • If no clot found try frontal then parietal burr holes
  • Sterile preparation and drape
  • Skin Incision
  • Aspetic procedure
  • Shave 5cm strip of hair at chosen site
  • Clean with Chlorhexidine and Alcohol
  • LA down to periosteum if time permits
  • Temporal Incision
  • 3cm vertical incision stright down to bone
  • Typically will bleed prpfusely
  • Control bleeding ie: from temporal artery, with firect pressure or artery forceps
  • Self-retaining retractor may assist haemostasis
  • Insert self-retaining retractor
  • Scrape periosteum off bone with scalpel, swab or periosteal elevator
  • Periosteum may get caught in drill bit
  • Reposition self-retaining retractor
  • Drilling Burr Hole
  • Attach drill bit and secure with Allen key
  • Set at 1cm depth initially
  • Drill to depth
  • Use 1cm depth initially for frontal and parietal sites but may need to go further
  • Depth stop will prevent bit entering into parenchyma
  • Drill perpendicular to skull maintainig moderate pressure
  • Drill until bit locks
  • Epidural blood should then escape
  • If haematoma has clotted may need to drill an additional 1 or 2 holes
  • If still not effective discuss with neurosurgeon to cut between holes with Kerrison ronguers to remove flap and suction clot
  • If no blood is evacuated dicuss with neurosurgeon before proceeding
  • Hold venturi drain in proximity to burr hole on free drainage
  • Continuous suctioning until arrive in theatre
  • Apply no pressure to brain during procedure

  
  
  Temporal burr hole in progress with self-retaining retractor and artery forceps on temporal artery

Complications

• Failure to evacuate blood
• Direct brain trauma

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References

Alfred Proedures Course. Cranial Decompression. 2017.
The Management of Acute Neurotrauma in Rural and Remote Locations. Neurological Society of Australiasia. 2009.