Differences in cerebral and hepatic oxygenation in response to intradialytic blood transfusion in patients undergoing hemodialysis.

Hemodialysis (HD) patients frequently experience severe anemia, requiring intradialytic blood transfusion. Severe anemia leads to deterioration of systemic tissue oxygenation. However, few reports have examined the effect of intradialytic blood transfusion on tissue oxygenation changes. This study aimed to (i) monitor the differences in tissue oxygenation in the brain and liver during intradialytic blood transfusion, and (ii) elucidate the clinical factors affecting cerebral and hepatic oxygenation. Thirty-eight HD patients with severe anemia requiring intradialytic blood transfusion were included (27 men, 11 women; mean age, 70.2 ± 1.6 years). Cerebral and hepatic regional oxygen saturation (rSO2) values were monitored using near-infrared spectroscopy (INVOS 5100c oxygen saturation monitor). Cerebral and hepatic rSO2 were significantly higher after than before blood transfusion (p < 0.001, both). Furthermore, hepatic rSO2 was significantly higher than cerebral rSO2 after transfusion (p = 0.004). In multivariable linear regression analysis, cerebral rSO2 changes were independently associated with the natural logarithm of hemoglobin (Hb) ratio (Hb after/before transfusion) (standardized coefficient: 0.367, p = 0.023), whereas hepatic rSO2 changes were independently associated with the natural logarithm of [Hb ratio/colloid osmotic pressure ratio (colloid osmotic pressure after/before transfusion)] (standardized coefficient: 0.378, p = 0.019). In conclusion, throughout intradialytic blood transfusion, brain and liver tissue oxygenation improved. Hepatic rSO2 was significantly higher than cerebral rSO2 at the end of HD. Furthermore, cerebral oxygenation changes were associated with only transfusion-induced Hb increase, whereas hepatic oxygenation changes were associated with both transfusion-induced Hb increase (positive changes) and ultrafiltration-induced colloid osmotic pressure increase (negative changes).