There is some evidence that paravertebral analgesia is similar to epidural analgesia in efficacy but superior in maintenance of blood pressure. This is a double blind, randomized control trial comparing paravertebral catheters to epidural catheters for the management of post thoracotomy analgesia. Both groups will undergo placement of a pre-induction epidural catheter as well as a surgically placed paravertebral catheter. Patients will also receive PCA morphine. The primary outcome will be daily morphine use measured in milligrams. The co-primary outcome will be time spent with a systolic blood pressure below 90mmHg. Outcomes will be measured during the first five postoperative days.