Lumbar drains are commonly placed to monitor spinal cerebrospinal fluid (CSF) pressures and drain CSF to augment spinal cord perfusion. Excessive CSF drainage or persistent leakage through the dural puncture site can lead to cerebral hypotension and creation of an intracranial subdural hematoma. Anesthesia providers need to be aware of the risk of subdural hematoma development after major thoracoabdominal surgery where placement and subsequent removal of a lumbar drain have occurred. We present a patient who had recurrent subdural hematoma secondary to persistent undiagnosed CSF leak from the dural puncture site after uncomplicated placement and removal of a lumbar drain.