Fig. 5.

Cerebral blood flow (CBF) and oxygen delivery (CDO₂) during hemodilution in humans. Data taken from five studies utilizing hemodilution and concurrent measures of CBF and arterial blood gases. The subject samples include 20 anesthetized tumor resection patients prior to surgery (filled circle) (33), eight patients with vasospasm following aneurysmal subarachnoid hemorrhage (filled square) (47), eight young healthy volunteers (upwards triangle) (73), five patients with unilateral internal carotid artery occlusion in addition to previous stroke or transient ischemic attacks (downwards triangle) (211), and 11 healthy young volunteers (filled diamond) (130), totaling 47 subjects [as all of the data collected in clinical patients, except for that of Ref. 211 (circled data point), followed the same trend as the studies using healthy patients, the data from Ref. 211 have been excluded from our representation of mean data]. Indeed, the unilateral internal carotid artery occlusion would have influenced CBF regulation and in turn likely explains the larger increase in CBF (on the patent side). The mean lines for both the CBF and CDO₂ graphs have been calculated as the linear slope from the mean data of each study weighted for sample size.