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.
- 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.