Reduction of injury during stroke by hemodilution is thought to be limited by the concurrent decrease in O2 carrying capacity. We determined if transfusion of cell-free, polymeric crosslinked hemoglobin during 2 hr of transient focal cerebral ischemia produced by the suture technique decreases infarct volume in halothane-anesthetized C57B/6 mice. Exchange transfusion with adipyl crosslinked, polymeric bovine hemoglobin at 20 min of ischemia decreased hematocrit from 42±1 to 28±1% with only a small decrease in total hemoglobin concentration (13±0.7 to 11±0.3 g/dL). Mean arterial pressure increased slightly from 80±2 to 88±3 mmHg during ischemia. Infarct volume measured at 22 hr reperfusion (66±8 mm3; SE; n=8) was less than in a non-transfused control group (96±9 mm3; n=8) with the same surgery and anesthesia duration. Perfusion was monitored in superior lateral cortex (ischemic border region) by laser-Doppler flowmetry. In 5 control mice, perfusion decreased to 29±4% of baseline at 15 min ischemia, was maintained at 27±3% at 120 min ischemia, and increased to 103±14% at 30 min reperfusion. In 4 other mice, perfusion decreased to 29±4% at 15 min ischemia, but increased after hemoglobin transfusion to 42±6% at 120 min ischemia and to 86±8% at 30 min reperfusion. Therefore, reducing hematocrit while maintaining hemoglobin concentration improves hemoglobin flux in the ischemic border region and reduces subsequent injury volume in the mouse.
|Original language||English (US)|
|State||Published - Mar 20 1998|
ASJC Scopus subject areas
- Molecular Biology