Value of cerebrospinal fluid drainage in perioperative management of thoracoabdominal aortic aneurysms

Objectives: The nightmare of thoracoabdominal aortic repair is spinal cord ischaemia with subsequent paraplegia. This study investigated the perioperative efficacy of cerebrospinal fluid (CSF) drainage as spinal cord protecting modality attempting to improve neurological results.

Methods: Between November 2000 and June 2007 we monitored the spinal cords of 97 patients undergoing thoracoabdominal aortic repair (open surgical replacement 27 patients=group I; endovascular stent-graft implantation 57 patients=group II; hybrid-procedure 13 patients=group III) with evoked potentials (EP). All patients obtained vital parameter- as well as constant CSF-pressure-monitoring. If CSF-pressure exceeded 15mmHg, CSF-drainage was performed.

Results: In group I-patients, CSF-drainage was necessary in 18 of 27 patients (66.7%). The allocation of Crawford-Classification-Types (CCT) splits as follows: CCT-I=39%, CCT-II=32%, CCT-III=18%, CCT-IV=11%. In group II-patients, CSF-drainage was carried out in 14 of 57 patients (24.6%; CCT-I=39%, CCT-II=61%). In group III-patients, CSF was drained in eight of 13 patients (61.5%; CCT-I=44%, CCT-II=56%). In case of intracranial pressure (ICP) increase, EP-alterations were observed. Timely CSF-drainage reversed these changes in all group II- and III-patients without subsequent neurological damage. Four group I-patients (14.8%) sustained irreversible neurological damages.

Conclusion: Our data indicates that intraoperative CSF-drainage is a valuable tool for intraoperative neuroprotective interventions in case of spinal cord ischaemia, detected either by EP-alterations or ICP-increase. Furthermore, it emphasizes its importance for the safety of patients with CCT-I and CCT-II thoracoabdominal aortic aneurysms.