The purpose of this study is to determine the feasibility of administering a predetermined amount of normal saline into the intrathecal or subarachnoid space via a small spinal catheter to reduce or eliminate the effects of previously injected spinal anesthetic following lower extremity orthopedic surgery.
Patients having elective lower extremity joint replacement surgery
Patients >18 years
Contraindications to spinal anesthesia (refusal, lumbar spinal hardware, spinal abnormalities)
Patient on anticoagulation not withheld
Patient receiving re-operation on the same joint
Prior intra-cranial bleeding