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Effects of chronic isovolaemic haemodilution on regional cerebral blood flow in conscious rats

Published online by Cambridge University Press:  23 December 2004

T. Frietsch
Affiliation:
Faculty of Clinical Medicine Mannheim, Department of Anesthesiology and Critical Care Medicine, Germany
C. Lenz
Affiliation:
Faculty of Clinical Medicine Mannheim, Department of Anesthesiology and Critical Care Medicine, Germany
W. Kuschinsky
Affiliation:
University of Heidelberg, Department of Physiology and Pathophysiology, Germany
K. F. Waschke
Affiliation:
Faculty of Clinical Medicine Mannheim, Department of Anesthesiology and Critical Care Medicine, Germany
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Summary

Background and objective: Acute isovolaemic haemodilution increases local and mean cerebral blood flow. It is not known whether a single haemodilution has a short-term effect only or whether it affects cerebral perfusion over a longer time period. In the present study, local and mean cerebral blood flow were determined in conscious rats after a 4, 24 and 48 h period following one-time haemodilution.

Methods: Thirty-six rats were randomized to three untreated sham groups and three groups of haemodilution (4, 24 or 48 h, n = 6 for each group). Isovolaemic haemodilution with albumin 5% aimed to a target haematocrit of 0.2. Local cerebral blood flow was measured in 38 brain regions by the iodo-[14C]antipyrine method in conscious normothermic rats.

Results: Isovolaemic haemodilution reduced haematocrit from 0.44 to 0.20. During the following 24 and 48 h periods, haematocrit remained low (0.22 and 0.21). Mean cerebral blood flow was similar in untreated sham groups (88 ± 12 after 4 h, 92 ± 11 after 24 h, 96 ± 10 mL 100 g−1 min−1 after 48 h). Haemodilution increased mean cerebral blood flow after 4 h (184 ± 11 mL 100 g−1 min−1), after 24 h (153 ± 13 mL 100 g−1 min−1) and 48 h (149 ± 15 mL 100 g−1 min−1) (P ≤ 0.05). Local cerebral blood flow increased in all 38 structures after 4 h haemodilution but decreased with time in six of 38 brain structures after 24 h and in 15 regions after 48 h (P ≤ 0.05).

Conclusions: A single one-time haemodilution increased mean cerebral blood flow for 2 days. However, local adaptation of cerebral blood flow to a chronic low haematocrit occurred but was heterogeneous within the brain.

Type
Original Article
Copyright
2004 European Society of Anaesthesiology

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References

Todd MM, Weeks JB, Warner DS. Cerebral blood flow, blood volume, and brain tissue hematocrit during isovolemic hemodilution with hetastarch in rats. Am J Physiol 1992; 263: H75H82.Google Scholar
Cole DJ, Drummond JC, Patel PM, Marcantonio S. Effects of viscosity and oxygen content on cerebral blood flow in ischemic and normal rat brain. J Neurol Sci 1994; 124: 1520.Google Scholar
Goslinga H, Heuvelmans JH, Schmid-Schonbein H. Hemodilution and rehydration in acute ischemic stroke. A preliminary report on the Amsterdam Stroke Study. Acta Med Austriaca 1991; 1: 4144.Google Scholar
Belayev L, Busto R, Zhao W, Clemens JA, Ginsberg MD. Effect of delayed albumin hemodilution on infarction volume and brain edema after transient middle cerebral artery occlusion in rats. J Neurosurg 1997; 87: 595601.Google Scholar
Yamauchi H, Fukuyama H, Ogawa M, Ouchi Y, Kimura J. Hemodilution improves cerebral hemodynamics in internal carotid artery occlusion. Stroke 1993; 24: 18851890.Google Scholar
Multicenter trial of hemodilution in acute ischemic stroke. I. Results in the total patient population. Scandinavian Stroke Study Group. Stroke 1987; 18: 691699.
Tu YK, Liu HM. Effects of isovolemic hemodilution on hemodynamics, cerebral perfusion, and cerebral vascular reactivity. Stroke 1996; 27: 441445.Google Scholar
Sakurada O, Kennedy C, Jehle J, Brown JD, Carbin GL, Sokoloff L. Measurement of local cerebral blood flow with iodo [14C]antipyrine. Am J Physiol 1978; 234: H5966.Google Scholar
Wallenstein S, Zucker CL, Fleiss JL. Some statistical methods useful in circulation research. Circ Res 1980; 47: 19.Google Scholar
Renkin EM, Joyner WL, Gustafson-Sgro M, Plopper G, Sibley L. Albumin extravasation rates in tissues of anesthetized and unanesthetized rats. J Appl Physiol 1989; 66: 20562060.Google Scholar
Payen JF, Vuillez JP, Geoffray B, et al. Effects of preoperative intentional hemodilution on the extravasation rate of albumin and fluid. Crit Care Med 1997; 25: 243248.Google Scholar
Todd MM. Cerebral blood flow during isovolemic hemodilution: mechanistic observations. Adv Pharmacol 1994; 31: 595605.Google Scholar
Waschke KF, Krieter H, Hagen G, Albrecht DM, Van Ackern K, Kuschinsky W. Lack of dependence of cerebral blood flow on blood viscosity after blood exchange with a Newtonian O2 carrier. J Cereb Blood Flow Metab 1994; 14: 871876.Google Scholar
Waschke K, Schrock H, Albrecht DM, van Ackern K, Kuschinsky W. Local cerebral blood flow and glucose utilization after blood exchange with a hemoglobin-based O2 carrier in conscious rats. Am J Physiol 1993; 265: H1243H1248.Google Scholar
Noria S, Cowan DB, Gotlieb AI, Langille BL. Transient and steady-state effects of shear stress on endothelial cell adherens junctions. Circ Res 1999; 85: 504514.Google Scholar
Takahashi M, Ishida T, Traub O, Corson MA, Berk BC. Mechanotransduction in endothelial cells: temporal signaling events in response to shear stress. J Vasc Res 1997; 34: 212219.Google Scholar
Langille BL. Morphologic responses of endothelium to shear stress: reorganization of the adherens junction. Microcirculation 2001; 8: 195206.Google Scholar
Bryan JrRM, Marrelli SP, Steenberg ML, Schildmeyer LA, Johnson TD. Effects of luminal shear stress on cerebral arteries and arterioles. Am J Physiol Heart Circ Physiol 2001; 280: H20112022.Google Scholar