Figure 1 Periodic distribution of NIRS data from CR, CL, T5 and T10 regions
ACP: Antegrade cerebral perfusion; CPB: Cardiopulmonary bypass
When compared to the baseline NIRS levels, more than 20% reduction was observed in 17 patients’ T5 NIRS values (56,7%, p<0.001), and 22 patients’ T10 values (73.3%, p<0.001) during ASCP period which was statistically more than the number of such patients in the preceding periods. The patient with paraparesis was in this group. A drop more than 36% of baseline occurred less frequently during the same period (in 1 patient’s T5 and in 7 patients’ T10 NIRS values, p=1,00 and p=0,016 respectively) with none of the patients experiencing any neurologic event. The only patient with more than 36% reduction in both T5 and T10 NIRS values had only 17 minutes of ASCP without any postoperative neurologic complication.
s100β levels at the postoperative 6th hour fell significantly with respect to the period corresponding to the end of ASCP (2.086 ± 0.971 vs 1.082 ± 0.82; p<0.001) (Table 2).
Lactate levels increased with the onset of ASCP reaching its highest level with termination of ASCP and diminishing afterwards in the postoperative period (pΣ <0.001, Table 2, Figure 2). Statistically significant differences were observed in lactate levels between the pairs as before ASCP and during ASCP (pΩ =0.002), during ASCP and at the end of ASCP (pΨ<0.001) (Table 2). Lactate levels in blood samples obtained from descending aorta during ASCP was significantly higher than the samples drawn concurrently from radial artery with a moderately positive correlation between them (4.52 ± 1.56 vs 3.86 ± 1.61 respectively, p=0.002 and r=0.655, p<0.001).