- Dexmedetomidine loading dose 1ug/Kg over 10 minutes then maintenance infusion of 0.5 ug/kg/h (range 0.3 to 0.7 ug/Kg/h), titrate to RASS of -4 (sluggish response to glabellar tap or loud stimulus)
- Fentanyl 1ug/Kg 5 minutes prior to skin infiltration with local anesthetic.
- Once sedated to RASS of -4, local anesthetic given (2ml 0.5 bupivacaine and 2ml 2% lignocaine with adrenaline) at each Burr hole site.
- Taper dexmedetomidine and stop once hemostasis achieved and skin closure commenced.
- Rescue bolus of midazolam 0.5 mg IV to max of 2.5mg given if not adequately sedated or with inadvertent movement during procedure.
Failure – switch to General Anesthesia:
- induction with fentanyl 2ug/kg IV
- thiopentone 3-5mg/kg titrate to LOC
- vecuronium 0.12 mg/Kg or atracurium 0.5mg ?kg
- Maintain anesthesia with 40% O2 in N20 and isoflurane or sevoflurane to MAC of 1
- reverse neuromuscular blockade with neostigmine and glycopyrrolate at end of procedure
Other meds for troubleshooting:
- Bradycardia: atropine 0.6mg IV
- Tachycardia: fluid bolus and esmolol 0.5mg/Ig
- Hypotension: fluid bolus then mephentermine 6mg bolus, repeat to max of 12
- Hypertension: labetalol 10mg bolus
Compared to GA, dexmedetomidine sedation with local anesthesia is:
- safe and effective
- associated with shorter OR time, lesser hemodynamic fluctuations, post-op complications and length of hospital stay.
Surve, Rohini M. et al. “Use Of Dexmedetomidine Along With Local Infiltration Versus General Anesthesia For Burr Hole And Evacuation Of Chronic Subdural Hematoma (CSDH)”. Journal of Neurosurgical Anesthesiology (2016): 1. Web.