Abstract TP168: Impairment of Cerebral Blood Flow Autoregulation in Patients With Acute Cerebral Infarction Recovered Within 7-10 Days After Onset

Abstract

InIntroduction: Cerebral blood flow (CBF) autoregulation is impaired after acute cerebral infarction (AIS). Although previous studies revealed that changes in cerebral oxygenation occurred when head-of-bed raised from flat to head-up position within 72hr after onset, chronological changes of this phenomenon had never been evaluated. Hypothesis: We hypothesized that the impairment of CBF autoregulation improved within 7-10 days after onset of AIS. We aimed to evaluated the chronological changes in oxygenated- (ΔHbO 2 ), deoxygenated- (ΔHb) and total-hemoglobin (ΔtHb) concentration in response to passive sitting between <72hr and 7-10 days after onset of AIS. Method: We repeatedly measured forehead ΔHbO2, ΔHb and ΔtHb in response to raise the head-of-bed to 30 degrees from spine within 72hr (1 st measurement) and 7-10 days (2 nd measurement) after onset of AIS by using time-resolved near-infrared spectroscopy. Difference in the ΔHbO2, ΔHb and ΔtHb values between two measurements were compared. We also evaluated Spearman Rank Correlation Coefficient of those values between affected and unaffected side in each measurement. Results: A total of 37 participants (mean age, 70.4±12.5 years; 13 females) with a first AIS hospitalization in the Seirei Mikatahara General Hospital, Hamamatsu, Japan, were enrolled. No significant differences of ΔHbO 2, ΔHb or ΔtHb in either affected or unaffected side were observed between two measurements. The ΔHbO 2, ΔHb or ΔtHb of the affected side did not correlate with those in the unaffected side at the first measurement (ΔHbO 2 ; r=0.197, p=0.282, ΔHb; r=0.065, p=0.695. and ΔtHb; r=0.193, p=0.245, respectively). Interestingly, the correlation coefficients of the ΔHbO 2, ΔHb and ΔtHb between affected and unaffected side at the 2 nd measurement were statistically significant (ΔHbO 2 ; r=0.420, p=0.011, ΔHb; r=0.398, p=0.017. and ΔtHb; r=0.490, p=0.003, respectively). Conclusion: Although cerebral oxygenation changes in relation to posture change did not correlate between affected or unaffected side within 72hr after onset, this difference was improved in 7-10 days after onset. Our result suggested that the impairment of CBF autoregulation improved, at least partially, within 7-10 days after onset of AIS.