Methodological error and spatial variability of organ blood flow measurements using radiolabeled microspheres

1991 ◽  
Vol 191 (1) ◽  
pp. 47-63 ◽  
Author(s):  
B. Zwissler ◽  
R. Schosser ◽  
C. Weiss ◽  
V. Iber ◽  
M. Weiss ◽  
...  
Keyword(s):  
Blood Flow ◽  
Spatial Variability ◽  
Methodological Error ◽  
Organ Blood Flow ◽  
Flow Measurements ◽  
Blood Flow Measurements

Evaluation of the role of cellular hypoxia in sepsis by the hypoxic marker [18F]fluoromisonidazole

1991 ◽  
Vol 261 (4) ◽  
pp. R965-R972 ◽  
Author(s):  
R. S. Hotchkiss ◽  
R. S. Rust ◽  
C. S. Dence ◽  
T. H. Wasserman ◽  
S. K. Song ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Blood Flow ◽  
Muscle Blood Flow ◽  
Organ Blood Flow ◽  
The Novel ◽  
Flow Measurements ◽  
Cellular Hypoxia ◽  
Blood Flow Measurements ◽  
And Control ◽  
Increased Retention

Underlying cellular hypoxia, which may be difficult to detect, has been postulated to be a major cause of morbidity and mortality in sepsis. We employed the novel hypoxic marker [18F]fluoromisonidazole to determine whether cellular hypoxia was present in a peritonitis model of sepsis in the rat. A second group of septic and control rats had organ blood flow measurements determined by the radiolabeled microsphere technique to relate possible ischemia to decreased organ perfusion. No evidence of cellular hypoxia was detected in skeletal muscle, brain, liver, heart, or diaphragm in the septic rats. Ligation of the femoral artery caused a greater reduction in flow (55% decrease vs. 20% decrease, P less than 0.05) and an increased retention of [18F]fluoromisonidazole in skeletal muscle of the septic rats. We conclude that sepsis does not invariably result in systemic, i.e., multiorgan, cellular hypoxia and that underlying cellular hypoxia is not the major pathophysiological abnormality in sepsis. The greater reduction in muscle blood flow and the increased retention of [18F]fluoromisonidazole in the ischemic muscle of septic rats implies that they may be more vulnerable to hypoxia.

Determinations of blood flow and shunting of 9- and 15-micrometer spheres in regional beds

1979 ◽  
Vol 237 (1) ◽  
pp. H25-H33 ◽  
Author(s):  
F. C. Fan ◽  
G. B. Schuessler ◽  
R. Y. Chen ◽  
S. Chien
Keyword(s):  
Blood Flow ◽  
Portal Vein ◽  
Venous Blood ◽  
Sampling Technique ◽  
Organ Blood Flow ◽  
Venous Sampling ◽  
Flow Measurements ◽  
Arterial Blood ◽  
Blood Flow Measurements ◽  
The Brain

In 17 pentobarbitalized dogs, the shunting of 15-micrometer and 9-micrometer microspheres was studied in the brain, myocardium, kidney, intestine, and lung. The veins of these organs were catheterized for constant blood withdrawal for 2 min by direct venipuncture. The ratio of microsphere radioactivity in the venous blood to that in the arterial blood gave the shunting of microspheres by the venous sampling technique. The 15-micrometer microspheres showed 2% or less shunting for all organs studied, whereas the 9-micrometer microspheres had shunting ranging from 3% in the coronary sinus to 24% in the portal vein. The shunting of 9-micrometer microspheres was also calculated from direct tissue counting, where the 15-micrometer spheres were considered to be completely entrapped. The results of direct tissue counting indicate that the 2-min venous sampling underestimates microsphere shunting. CO2 administration increased significantly the shunting of 9-micrometer spheres, whereas the shunting of 15-micrometer spheres determined by venous sampling remained less than 2%. Consideration of shunting indicates that the 15-micrometer microspheres might be more appropriate for regional organ blood flow measurements, including the myocardium.

Clinical Utility of Quantitative Cerebral Blood Flow Measurements during Internal Carotid Artery Test Occlusions

Neurosurgery ◽  
2002 ◽  
Vol 50 (5) ◽  
pp. 996-1005 ◽  
Author(s):  
Randolph S. Marshall ◽  
Ronald M. Lazar ◽  
William L. Young ◽  
Robert A. Solomon ◽  
Shailendra Joshi ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Clinical Utility ◽  
Internal Carotid ◽  
Flow Measurements ◽  
Blood Flow Measurements

Doppler Blood Flow Measurements in Chronic Animal Preparations

1975 ◽  
Vol 49 (3) ◽  
pp. 17P-17P
Author(s):  
Maurice R. Cross ◽  
Clive Weller ◽  
E. B. Raftery
Keyword(s):  
Blood Flow ◽  
Flow Measurements ◽  
Blood Flow Measurements

Duplex Sonography of Normal Renal Allografts

1989 ◽  
Vol 30 (1) ◽  
pp. 53-56 ◽  
Author(s):  
B. Schwaighofer ◽  
F. Kainberger ◽  
F. Fruehwald ◽  
P. Huebsch ◽  
N. Gritzmann ◽  
...  
Keyword(s):  
Blood Flow ◽  
Resistive Index ◽  
Duplex Sonography ◽  
Invasive Technique ◽  
Flow Measurements ◽  
Renal Allografts ◽  
Significant Difference ◽  
Main Renal Artery ◽  
Long Term Follow Up ◽  
Blood Flow Measurements

Thirty-five patients with normal renal allografts as well as 10 healthy volunteers with normal native kidneys were examined by duplex sonography. Blood flow measurements were performed in the main renal artery as well as in segmental, interlobar and arcuate arteries. In both groups the normal range of variation in blood flow was defined by using the resistive index (RI). Doppler wave forms and RI of main renal arteries were both similar to those of their branches. In renal allografts as well as in native kidneys the blood flow pattern showed a rapid up-slope in systole followed by a gradual down-slope in early diastole, with a persistent flow throughout diastole. In addition, there was no significant difference in the RI between allografted and native kidneys. The interobserver variability was less than 10 per cent. The mean RI was 0.68 using all data points. Vascular rejection in 11 patients could be discriminated significantly (p<0.001). Duplex sonography is useful in evaluating renal blood flow. This simple and non-invasive technique seems to be useful in long-term follow-up of renal allograft recipients.

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