|
|
||||||||
Departments of Anesthesiology and Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
The effect of isovolemic hemodilution on the circulation of red blood cells (RBCs) in the cerebrocortical capillary network was studied by intravital videomicroscopy with use of a closed-cranial-window technique in the rat. Velocity and supply rate of RBCs were measured by tracking the movement and counting the number of fluorescently labeled cells. Arterial blood was withdrawn in increments of 2 ml and replaced by serum albumin. Arterial blood pressure was maintained constant with an infusion of methoxamine. Both velocity and supply rate of RBCs increased, by approximately equal amounts, as arterial hematocrit was reduced from 44 to 15%. The maximum increase in RBC velocity was 4.6 and in RBC supply rate was 5.2 times the baseline value. Calculated lineal density of RBC, an index of capillary hematocrit, did not change with hemodilution. The results suggest that RBC flow and oxygen supply in the cerebral capillary network are maintained during isovolemic hemodilution. The "optimal hematocrit" is as low as 15%.
cerebral blood flow; microcirculation; anemia; plasma skimming; oxygen transport; red blood cell
This article has been cited by other articles:
![]() |
M. Licker, C. Ellenberger, J. Sierra, A. Kalangos, J. Diaper, and D. Morel Cardioprotective Effects of Acute Normovolemic Hemodilution in Patients Undergoing Coronary Artery Bypass Surgery Chest, August 1, 2005; 128(2): 838 - 847. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Tonnesen, A. Pryds, E. H. Larsen, O. B. Paulson, J. Hauerberg, and G. M. Knudsen Laser Doppler flowmetry is valid for measurement of cerebral blood flow autoregulation lower limit in rats Exp Physiol, May 1, 2005; 90(3): 349 - 355. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Yoshitani, M. Kawaguchi, M. Iwata, N. Sasaoka, S. Inoue, N. Kurumatani, and H. Furuya Comparison of changes in jugular venous bulb oxygen saturation and cerebral oxygen saturation during variations of haemoglobin concentration under propofol and sevoflurane anaesthesia Br. J. Anaesth., March 1, 2005; 94(3): 341 - 346. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Nemoto, S. Sheth, M. Guiou, N. Pouratian, J. W. Y. Chen, and A. W. Toga Functional Signal- and Paradigm-Dependent Linear Relationships between Synaptic Activity and Hemodynamic Responses in Rat Somatosensory Cortex J. Neurosci., April 14, 2004; 24(15): 3850 - 3861. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. M. T. Hare, C. D. Mazer, W. Mak, R. M. Gorczynski, K. M. Hum, S. Y. Kim, L. Wyard, A. Barr, R. Qu, and A. J. Baker Hemodilutional anemia is associated with increased cerebral neuronal nitric oxide synthase gene expression J Appl Physiol, May 1, 2003; 94(5): 2058 - 2067. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. F. Duebener, T. Sakamoto, S.-i. Hatsuoka, C. Stamm, D. Zurakowski, B. Vollmar, M. D. Menger, H.-J. Schafers, and R. A. Jonas Effects of Hematocrit on Cerebral Microcirculation and Tissue Oxygenation During Deep Hypothermic Bypass Circulation, September 18, 2001; 104 (2009): I-260 - I-264. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |