General Versus Regional Anesthesia in Peripheral Arterial Surgery

Participants will receive subarachnoid (spinal) anesthesia with 15-20 mg of isobaric bupivacaine 0.5% and 100 μg of intrathecal morphine. Clonidine (1 μg/kg) may be added at the discretion of the anesthesiologist. Sedation will be achieved with intravenous midazolam (up to 5 mg), fentanyl (up to 100 μg), and/or target-controlled infusion of propofol. Patients will remain spontaneously breathing throughout the procedure and receive supplemental oxygen via nasal cannula.

Participants will undergo general anesthesia induced with intravenous propofol (1.5-2.5 mg/kg) or etomidate (0.2-0.3 mg/kg), remifentanil (0.2-0.4 μg/kg/min), and rocuronium (0.6 mg/kg), followed by endotracheal intubation and controlled mechanical ventilation. Maintenance will include continuous remifentanil infusion and inhaled sevoflurane. Ventilation parameters will follow a protective strategy (tidal volume 6-8 mL/kg predicted body weight and PEEP of 5 cmH₂O).