OBJECTIVETo evaluate the clinical efficacy of two brain protective methods for aortic operation according to S100beta protein (S100beta) and interleukin-6 (IL-6) in cerebrospinal fluid (CSF).

METHODSFrom November 2004 to April 2005, 14 patients who underwent aortic operations with circulatory arrest were alternatively allocated to one of two methods of brain protection: only deep hypothermic circulatory arrest (core temperature, 18 degrees C) for descending thoracic aorta operations (group DHCA, n = 5) or selective antegrade cerebral perfusion (core temperature, 20 degrees C; flow rate, 10 ml kg(-1) min(-1)) for aortic arch operations with DHCA (group ASCP, n = 9). Indications for surgical intervention were Stanford type A dissection in 11 patients, Stanford type B dissection in 2 patients, false aneurysm on thoracoabdominal aorta in 1 patient. S100beta and IL-6 in CSF were assayed in all patients from each group before cardiopulmonary bypass, as well as 0, 6, 12, 24, 48, 72 h after the operation.

RESULTSThere were no significant differences in lowest core temperature (P > 0.05), hematocrit in lowest core temperature (P > 0.05) and the velocity of rewarming. Mean circulatory arrest time in ASCP group was significant longer than in DHCA group (P < 0.05). There were much more patients with jugular arteries impaired or accompanied with related cerebrovascular diseases in group ASCP compared to group DHCA. The baseline of S100beta in CSF before cardiopulmonary bypass was no difference. S100beta value in CSF ascended to peak level in 12 h after the operation, showing significantly higher in group DHCA than in group ASCP [DHCA vs. ASCP, (0.90 +/- 0.11) microg/ml vs. (0.61 +/- 0.26) pg/ml]. In most hours after operation there was significant intergroup difference. IL-6 value in CSF ascended to peak level in 12 h postoperative for group DHCA and 0 h postoperative for group ASCP. There was no significance difference observed in IL-6 of CSF between two groups except 6 h and 12 h postoperative.

CONCLUSIONSBrain ischemic injury occurred during aortic operations assisted by brain protective methods is not serious. Unilateral ASCP which can delivery adequate oxygen to brain during circulation arrest has some advantage of alleviating ischemic injury compared with only DHCA.