Spinal Anesthesia Versus General Anesthesia Using Laryngeal Mask Airway for Anorectal Surgeries in Prone Position

Spinal anesthesia in sitting position was done under complete aseptic technique through a standard midline approach. One and a half millilitres of 0.5% bupivacaine (7.5 mg) was injected through a 25 Gauge pencil-point needle into the subarachnoid space at L3-L4 or L4-L5 interspace. All patients were kept in a head-up position for 3 minutes. The patient was then asked to turn him- or herself into the prone position on the surgical table with the help of the surgical and anesthetic teams.

General anesthesia was induced using fentanyl 2 mcg/kg and Propofol 2-3 mg/kg. Any stomach contents were then suctioned through an oro-gastric tube to reduce the risk of regurgitation. Proper (weight-based) classic laryngeal mask airway was then blindly inserted. laryngeal mask airway was then properly fixed to the face and anesthesia was maintained with isoflurane 1-2% in 50% Oxygen/air mixture.