Association between intraoperative cerebral microembolic signals and postoperative neuropsychological deficit: comparison between patients with cardiac valve replacement and patients with coronary artery bypass grafting
- Departments of Neurology, Psychosomatic Medicine and Surgery, Rikshospitalet, The National Hospital, University of Oslo, N 0027, Norway
- Dr SK Brækken, Department of Neurology, Ullevål Hospital, 0407 Oslo, Norway. Telephone 0047 22118650; fax 0047 23015949.
- Received 5 November 1997
- Revised 2 March 1998
- Accepted 19 March 1998
Abstract
OBJECTIVES To examine the association between intraoperative cerebral microembolic signals (MES) and postoperative neuropsychological deficit in patients with valve replacement (VR) and patients with coronary artery bypass grafting (CABG).
METHODS Neuropsychological examination (10 tests) was performed 1–2 days before and 2 months after surgery (VR (n=26) and CABG (n=14)). The intraoperative number of cerebral MES were monitored from the right middle cerebral artery using transcranial Doppler.
RESULTS A higher number of cerebral MES were detected in VR patients with neurological deficit (6/26) compared with those without deficit (20/26) (MES median number 2083 v645, p=0.04). No such difference was found in patients with CABG (2/14v 12/14) (MES median number 50 v 112, p=0.2).
CONCLUSION A high number of MES were detected in patients with VR with neuropsychological deficit. In patients with CABG with such a deficit, a low number of MES were detected. This difference in number may be explained by relatively more gaseous emboli in the first and more solid in the second. However, the results in the patients with CABG should be interpreted with caution due to the few patients in this subgroup.
