Rural Medicine: Cranial Burr Hole

Rural Medicine: Cranial Burr Holes

Jess Mason, MD and David Beffa, MD

• Case: A young child presents with a head injury after a fall from 3-4 foot height onto a hard surface about 45 minutes prior to arrival. The child initially looks fine and the exam is normal except for a right-sided hematoma and hemotympanum. Over the next 15-20 minutes, the child rapidly deteriorated with declining mental status and unequal pupils. CT revealed an epidural hematoma with midline shift.
• Time to neurosurgical decompression is key. In settings where there will be delay to decompression, a cranial burr hole may be indicated.
• Indications for an emergency burr hole may include rapid clinical deterioration (eg,declining GCS, unequal pupils), an expanding hematoma (epidural or subdural), and prolonged time to neurosurgical decompression.

PITFALLS

• Don’t forget the basic management of elevated intracranial pressure:
  • Elevate the head of the bed.
  • Ensure adequate sedation.
  • Maintain normoxia and normocapnia
  • Give mannitol or hypertonic saline.
  • Avoid hypotension.
• EMRAP:HD video on cranial burr hole: https://www.emrap.org/episode/cranialburrhole/cranialburrhole
• Steps of procedure (to be done on the side of the blown pupil)
  • Knowing the anatomy from the CT head will be helpful. You can measure the thickness of the skull table so you know approximately how deep you need to go.
  • Prepare the site using sterile technique.
  • If no CT is available and the procedure is done blind, the entry site is 2 cm superior and 2 cm anterior to the tragus on the ipsilateral side of the blown pupil
  • Have an assistant hold the patient’s head hard and steady during the procedure.
  • Make a 3-5 cm vertical skin incision down to bone.
  • Insert self-retaining scalp retractor to expose periosteum.
  • Expose the skull and elevate the periosteum using the periosteal elevator.
  • Trephination technique varies by device. You may feel a change from smooth to rough as you move from outer to inner skull table.
  • An epidural hematoma will start to drain when you get through the inner table. If a subdural hematoma is present, an additional step is needed which involves a 3-sided incision to form a flap in the dura mater.
  • Place a sterile dressing.