As a new medical director, I thought to myself, “What is the worst that could happen at our rural, 12-bed ED?” The scenarios we all know came to mind: pericardiocentesis, thoracotomy, lateral canthotomy, resuscitative endovascular balloon occlusion of the aorta, and skull trephination (burr hole). At our monthly departmental meetings, we reviewed all of these procedures so we would be ready. I ordered the necessary kits so we would have the tools on-site. Our hospital had never even had a skull trephination kit before. The one I ordered arrived the day before a 2-year-old patient arrived at triage.
A 2-year-old male was brought to the emergency department by his mother after falling out of a shopping cart seat and striking his head. He initially appeared well and was running around the triage room. After a period of observation, he became increasingly somnolent, and on repeat exam, his pupils were slightly unequal. A head CT revealed a large epidural hematoma with midline shift. His pupils quickly became significantly worse at 6 mm and 2 mm, and he became unresponsive. I intubated him and called the nearest pediatric trauma center (one hour away) to begin arranging for helicopter transport. During the conversation with the trauma surgeon at the major academic center, I told him I was planning on doing an emergent burr hole. He said, “I’ve never done one of those—it’s up to you.”
I had seen one of these in residency and went to the supply room to find the newly arrived burr hole kit, took a deep breath, then started to prepare for the procedure by reviewing the CT.
I performed the burr hole with the technique described below and evacuated 150 mL of blood. The pupils improved. We placed a sterile dressing on the wound, and the helicopter team transported the patient to the pediatric trauma center.
One month later, the mother brought the boy back to the emergency department. The patient was running around the emergency department with no deficits and gave me a hug.
Location to Drill
Emergency department skull trephinations are done in the temporal location 2 cm anterior and 2 cm superior to the tragus.1
- Measure the skull thickness on CT to set stopper depth (see Figure 1).
- Shave the hair with clippers; sterile prep and drape.
- Inject local anesthetic and then make a 4-cm vertical skin incision down to the periosteum at a point 2 cm superior and 2 cm anterior to the tragus.
- Use a periosteal elevator to expose the skull.
- Have an assistant hold the patient’s head firmly prior to drilling.
- Apply the trephine with gentle, steady pressure until the skull is penetrated. The two nonautomated choices for trephine are the Integra hand crank model with stopper (see Figure 1) and the Galt trephine (see Figure 2). The bone fragment may come out in the device or may need to be removed with forceps. Place the bone fragment in a sterile cup with saline.
- Once the bone fragment is removed, the clot may not immediately extrude. Use a small sterile pediatric suction catheter to facilitate hematoma drainage.
- If identified, the bleeding artery (usually the middle meningeal) may be ligated/clamped.1
- Emergency department skull trephinations should only be performed in the temporal region to avoid venous sinus injury and complications of air embolism or hemorrhage.
- Avoid plunging by using the stopper on the hand crank and by measuring skull thickness on the CT image.
- Infection is a possibility.
Trephinations of the skull have been found in human skulls older than 10,000 years of age. Skulls from virtually every major civilization show evidence of successful trephinations. There are three common methods for performing trephinations:2
- Scraping bone (see Figure 3)
- Drilling a series of small holes and connecting them
- Making crosshatch cuts in the bone and connecting them to remove a rectangular piece of bone1