Effects of Head Elevation on Cerebral Oxygenation in Acute Cerebral Infarction

This study clarifies the effects of head elevation on cerebral oxygenation in patients with acute cerebral infarction. We included 76 patients with anterior circulation cerebral infarction admitted to the stroke care unit within 7 days of symptom onset. Using near-infrared spectroscopy (NIRS), we measured regional saturation oxygen (rSO2), oxygenated haemoglobin (O2Hb), deoxygenated haemoglobin (HHb), and total haemoglobin (THb) in both the affected hemisphere (AH) and unaffected hemisphere (UH) after raising the head to 0°, 30°, and 60° for 1 minute each. The mean arterial pressure (MAP) was measured non-invasively at each position. Our result demonstrated a significant decrease in O2Hb as the head elevation angle (HEA) increased, with no observable interaction between the AH and UH. A significant decrease in rSO2 interaction was observed. In contrast, the HHb and THb levels changed significantly as the HEA increased, although no interactions were identified. No significant correlations existed between the observed changes in O2Hb, HHb, THb, or rSO2 and changes in MAP at each HEA.