Thoracic Spinal Versus Epidural Anesthesia for Nephrectomy in Obstructive/Restrictive Lung Disease Patients

Spinal anesthesia will be performed for patients of the TSA group at the T7-T8 intervertebral space, using a 27 G pencil point needle with an introducer (Braun Melsungen, Melsungen, Germany). When correct placement is confirmed by the free flow of clear CSF, 1.5 ml of hyperbaric Bupivacaine 0.5% (7.5 mg) in addition to 0.5 ml Fentanyl (25 μg) \& 5 μg dexmedetomidine will be injected.

Epidural anesthesia will be performed for patients of the TEA group at the T7-T8 intervertebral space, using the "Prefix Custom Epidural Anesthesia Tray" with an 18 G Tuohy epidural needle \& a 20 G epidural catheter. Patients will initially receive 5-10 ml of a mixed preparation of 0.5% isobaric Bupivacaine with 2 μg Fentanyl per ml volume as a bolus dose via the epidural catheter, this will be followed by a continuous infusion of 5-10 ml/hr started 1 hour after the bolus dose \& continued throughout the procedure.