STA-MCA Bypass Under Local Anesthesia

The superficial temporal artery to middle cerebral artery (STA-MCA) bypass procedure has continually evolved and new strategies have been advocated to reduce anesthetic or surgical mortality and morbidity. Further simplifying and decreasing the invasiveness of STA-MCA bypass by performing this operation without endotracheal general anesthesia was deemed feasible in certain subsets of patients.

We performed STA-MCA bypass using local anesthesia using a sedative in 45 patients with hemodynamically compromised cerebrovascular occlusive disease as well as multiple comorbidities in the period between February 2010 and April 2016. The technique is based on preoperative identification of the point at which the donor and recipient vessels are in closest proximity. The preoperative use of computed tomography angiography allowed us to identify the target point precisely and use a minimally invasive procedure. All patients received dexmedetomidine as the sole sedative agent, together with scalp block local anesthesia with an unsecured airway.

Successful STA-MCA bypass surgeries were achieved via a preselected minimally invasive approach in all cases. There was good hemodynamic stability throughout surgery. No airway/ventilation complications occurred and no patient was converted to general anesthesia. The patients subjectively tolerated this technique well with a high rate of satisfaction. Postoperative magnetic resonance angiography confirmed patent bypass in 44 of 45 patients (patency rate of 97.8%). There were two postoperative hyper-perfusion syndromes and one cerebral ischemia with transient neurological symptoms (postoperative complication rate of 6.3%). No recurrence of ipsilateral cerebral ischemia was observed during the follow-up periods. There was one contralateral cardiogenic cerebral embolism during the follow-up period. The overall stroke rate was calculated as 1%/patient/year.

Our initial experience confirms the feasibility of performing STA-MCA bypass under local anesthesia without endotracheal general anesthesia.