Redistribution of local hepatic blood flow during acute bleeding and prolonged hemorrhagic hypotension studied using fluorochromed plasma proteins and surface PO2 measurements.
The present study was performed in order to study the development of sinusoidal blood flow heterogeneity during stepwise bleeding and during prolonged hemorrhagic hypotension. Two methods have been applied: Hepatic surface oxygen tension was measured by a multi-gold-wire-cathode. Sinusoidal perfusion patterns were demonstrated by use of fluorochromed plasma proteins. During stepwise bleeding the relative decrease of the five individual sPO2 curves showed different slopes in the same rat thus indicating a flow dependent heterogeneity. The corresponding perfusion patterns were characterized by an irregular convection front. Time dependent flow heterogeneity resulted in a perfusion pattern showing predominantly perfused sinusoids and low or no flow sinusoids, whereby the predominantly perfused sinusoids might be taken as sinusoidal shunts. It is concluded that stepwise bleeding results in a functional redistribution depending upon the degree of reduced flow, while long time induced microcirculatory changes result in sinusoidal shunt flow depending upon morphological alterations.
Schywalsky
M
M
Department of Physiology, Medical School Hannover, Federal Republic of Germany.
Metzger
H P
HP
D000818:Animals; D001798:Blood Proteins / Q000378:metabolism; D005456:Fluorescent Dyes; D006470:Hemorrhage / Q000503:physiopathology*; D007022:Hypotension / Q000503:physiopathology*; D008102:Liver Circulation / Q000502:physiology*; D008833:Microcirculation / Q000503:physiopathology; D010100:Oxygen / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012039:Regional Blood Flow / Q000502:physiology
D001798:Blood Proteins; D005456:Fluorescent Dyes; D010100:Oxygen