Intrathecal Morphine Versus Intravenous Methadone for Postoperative Analgesia Following Retroperitoneal Lymph Node Dissection.

Intrathecal preservative free morphine (duramorph) 200 mcg with 7.5mg of hyperbaric bupivacaine placed by a spinal needle prior to induction of general anesthesia (n=71)

Intravenous methadone dosed at 0.2 mg/kg Ideal Body weight up to a maximum dose of 20mg, rounded to the nearest milligram, for all patients given during the induction of general anesthesia (n=71)