A 69-year-old woman underwent thoraco-abdominal aortic aneurysm repair with cerebrospinal fluid drainage (CSFD). The initial CSF pressure was elevated to approximately 25 cmH(2)O, and clear CSF was continuously drained at a rate of 30 ml/h with the drainage level at 10-20 cmH(2)O. The CSF became bloody when cardiopulmonary bypass was terminated. The total volume of CSF drained was approximately 300 ml at the conclusion of the 638 min operation. Three hours later, she suffered a series of generalized seizures because of intracranial hemorrhage (ICH). It was suggested that excessive drainage of CSF was associated with ICH. Meticulous control of drainage volume combined with standard pressure-based management may be the key to avoiding these complications.