Trauma Crani:

- after intubation, turn bed 90 degrees with the operative side facing away and the ET tube facing anesthesia. 

- position supine, head turned as much as you can - if patient is in c-collar or old, may need to bump shoulder in order to get enough posterolateral exposure of head

- shave generously, at least half head, sometimes whole head is easier.

- incision 1 cm off midline (plan incision 1 cm off midline, and then plan burr holes 1 cm from incision, that way you are 2 cm from sinus). Start anterior at the edge of hairline then travel back along the vertex - posterior limit is transverse sinus (and realistically, how far back you can reach on the head, which is a function of positioning). Travel laterally above the root of zygoma, then curve in front of ear -  stay 1 cm away. Any closer to tragus and you risk violating EAM, any further and you risk facial nerve.

- use the knife to cut down to bone; over temporalis muscle, knife through skin to temporalis and then bovie through temporalis. If you hit STA, bipolar it until it stops bleeding.
- raney clips on scalp. not everyone likes these. some people like them edge to edge on scalp, some only like them where scalp is bleeding, some never use them at all. if you use them, make sure to include galea in clips. 

- if not super emergent, consider stopping at pericranium and harvesting pericranial flap in case you get into frontal sinus. Also consider trying to save STA.... In a true crash crani, all you care about is speed; aim to get from skin incision to open dura in 15 mins, and to get out of the OR and into the ICU in less than hour. 

- position periosteal at the root of the zygoma, scrape upwards to get temporalis muscle off in one piece quickly. 

- retract flap using whatever system suits you; many like the towel clamps on flap and then some system to attach the towel clamps to

- Burr holes : keyhole, right above root of zygoma (as far down as you can get basically), posterior at least 1-2 cm above transverse sinus if not more, and then 1-2 up top - at least 2 cm off midline.

- remove remaining bone left by perforator drill bit, with straight curette, dissect off dura with woodson; some people will use other devices like penfield 1 or 3 to get additional dura off bone.
- turn the crani - start at the temporal bone. When turning on forehead, if you start at lateral edge of head and turn flap up towards forehead (rather than stating at the vertex and turning down) less risk of getting into frontal sinus.

- if blood starts coming out at copious volume when you are near the vertex, it may just be a venous lake in bone; apply bone wax to bone edges; if it stops, its not the sinus. If it is the sinus, do not panic, put a big gelfoam over it and wait for it to stop. Do not use small gelfoam for this, there's a chance it'll get sucked into the sinus and cause an obstruction.

- dissect dura off bone, remove bone flap

- if you caused a durotomy with the footplate or with the burr holes, reasonable to make a c-shaped dural opening. Alternatively, if you think there is a good chance you'll be able to do dural re-closure/bone replacement immediately, also reasonable to make c-shaped incision as it is easier to close.

- if brain is very swollen and you are aiming for maximum decompression, open dura in stellate manner.
- if brain is swollen, make sure to extend the craniotomy flush to the floor of the middle fossa - if this is not done, the temporal lobe will not be decompressed and the patient can still have temporal lobe swelling and uncal herniation even after decompression. use rongeur in biting, not tearing or twisting motions. 

- evacuate hematoma.
- if you are doing a loculated/membraney subdural, do not strip the membrane. Peeling off membrane takes off a layer or two of cortical cells and predisposes people to seizures/status.
- inspect dural edge and bone edge for bleeding, acquire hemostasis.
- replace bone flap if you think appropriate.
- always leave a drain. always leave a drain. always leave a drain. curl it around so the entire flap is included within the area that is being drained. the point is you can't get perfect hemostasis because you don't want to apply so much electrocautery to the flap so that it won't heal, but if you leave without a drain or place it suboptimally people can get really bad subgaleal hematomas. and a subgaleal hematoma in a person with no bone = epidural hematoma.
- close the galea. remember the words of harvey cushing.
- staples to skin for speed