Distensibility of portacaval shunts in portal hypertensive cats: index of contractility model

1994 ◽  
Vol 72 (6) ◽  
pp. 687-692
Author(s):  
Andrés C. Inglés ◽  
Dallas J. Legare ◽  
W. Wayne Lautt
Keyword(s):  
Blood Flow ◽  
Venous Pressure ◽  
Resistance Index ◽  
Portal Blood Flow ◽  
Portal Blood ◽  
Total Occlusion ◽  
Shunt Resistance ◽  
Wide Range ◽  
Flow Through ◽  
And Control

Complete shunting of portal blood flow through portacaval shunts was obtained using a constrictor around the portal vein to gradually produce a total occlusion. After 4 weeks, acute experiments were conducted in anesthetized cats. Blood from the femoral artery was shunted through a pump to supply and control the entire portal blood flow. As shunted portal blood flow was varied over a wide range, the portal shunt resistance showed distensibility. Decreasing portal venous pressure from 15.0 ± 0.9 to 11.1 ± 0.6 mmHg (1 mmHg = 133.3 Pa) resulted in elevations of resistance of 58%. The relation between the resistance (R) and the distending pressure (Pd) was a constant, the index of contractility (IC), where IC = R∙Pd3. In steady state, the IC was 485 ± 55 mmHg4∙mL−1∙min∙kg and did not change passively in response to changes in portal blood flow. In conclusion, portacaval shunts are passively distensible, and resistance is altered as a cubic function of the distending pressure. Because resistance is altered both actively and passively, the IC should prove useful to differentiate these alternatives for evaluation of changes in portal hypertensive therapy.Key words: portacaval shunts, distensibility model, vascular resistance, index of contractility.

RELATIONSHIP OF PORTAL BLOOD FLOW TO METABOLIZABLE ENERGY INTAKE OF CATTLE

1984 ◽  
Vol 64 (5) ◽  
pp. 16-17 ◽  
Author(s):  
G. HUNTINGTON
Keyword(s):  
Blood Flow ◽  
Energy Intake ◽  
Portal Blood Flow ◽  
Metabolizable Energy ◽  
Portal Blood ◽  
Holstein Cows ◽  
Flow Energy ◽  
Flow Through ◽  
Metabolizable Energy Intake ◽  
Relationship Of

Blood flow through portal-drained viscera (PBF) was related to metabolizable energy intake (MEI) in six Hereford × Angus heifers (41 observations), three nonlactating Holstein cows (four observations) and four lactating Holstein cows (14 observations). The linear equation (R2 = 0.75, Sy.x = 55) was PBF (L/h) = 352 + 5.8 ± 0.5 (MEI, MJ/day). Key words: Cattle, portal blood flow, energy intake

Portal Blood Flow as Measured by the Doppler Shift Technique in Sheep Fed Chopped Forages

1975 ◽  
Vol 41 (2) ◽  
pp. 596-600 ◽  
Author(s):  
L. R. Prewitt ◽  
D. R. Jacobson ◽  
R. W. Hemken ◽  
R. H. Hatton
Keyword(s):  
Blood Flow ◽  
Doppler Shift ◽  
Portal Blood Flow ◽  
Portal Blood ◽  
Shift Technique

Krypton 85 myocardial blood flow: precordial scintillation versus coronary sinus sampling

1965 ◽  
Vol 209 (4) ◽  
pp. 705-710 ◽  
Author(s):  
Michael D. Klein ◽  
Lawrence S. Cohen ◽  
Richard Gorlin
Keyword(s):  
Blood Flow ◽  
Myocardial Blood Flow ◽  
Coronary Sinus ◽  
Human Subjects ◽  
Radioactive Decay ◽  
Empirical Correction ◽  
Wide Range ◽  
Actual Flow ◽  
Flow Through ◽  
High Degree

Myocardial blood flow in human subjects was assessed by comparative simultaneous measurement of krypton 85 radioactive decay from coronary sinus and precordial scintillation. Empirical correction of postclearance background from precordial curves yielded a high degree of correlation between flows derived from the two sampling sites (r = .889, P < .001). Comparison of left and right coronary flows in nine subjects revealed similarity in flow through the two vessels over a wide range of actual flow values (r = .945, P < .001).

scholarly journals Portal Blood Flow and Oxygen Usage in Dogs after Hemorrhage

1970 ◽  
Vol 172 (2) ◽  
pp. 284-290 ◽  
Author(s):  
DENIS F. J. HALMAGYI ◽  
ANTHONY H. GOODMAN ◽  
MILES J. LITTLE ◽  
MERRILYN KENNEDY ◽  
DESMOND VARGA
Keyword(s):  
Blood Flow ◽  
Portal Blood Flow ◽  
Portal Blood

Enhanced hepatic portal blood flow induced by prostaglandin E1 following liver transplantation in pigs

Surgery Today ◽  
1994 ◽  
Vol 24 (7) ◽  
pp. 621-626 ◽  
Author(s):  
Kazuhiro Tsukada ◽  
Takeo Sakaguchi ◽  
Takemi Tomiyama ◽  
Katsuyuki Uchida ◽  
Yoshinobu Sato ◽  
...  
Keyword(s):  
Liver Transplantation ◽  
Blood Flow ◽  
Prostaglandin E1 ◽  
Portal Blood Flow ◽  
Portal Blood ◽  
Hepatic Portal

Does the direction of portal blood flow determine outcome with small-diameter prosthetic H-graft portacaval shunt?

Surgery ◽  
1997 ◽  
Vol 121 (1) ◽  
pp. 95-101 ◽  
Author(s):  
Alexander S Rosemurgy ◽  
James G Norman ◽  
Sarah E Goode
Keyword(s):  
Blood Flow ◽  
Small Diameter ◽  
Portacaval Shunt ◽  
Portal Blood Flow ◽  
Portal Blood

scholarly journals Portal Vein Dopplerflowmetry in healthy sheep according to age

2017 ◽  
Vol 37 (10) ◽  
pp. 1172-1176 ◽  
Author(s):  
Alexandra F. Belotta ◽  
Bianca P. Santarosa ◽  
Danilo O.L. Ferreira ◽  
Sílvia M.F. Carvalho ◽  
Roberto C. Gonçalves ◽  
...  
Keyword(s):  
Blood Flow ◽  
Portal Vein ◽  
Portal Blood Flow ◽  
Portal Blood ◽  
Mean Values ◽  
Pulsed Doppler Ultrasound ◽  
Healthy Sheep ◽  
Vein Diameter ◽  
Congestion Index ◽  
Post Hoc

ABSTRACT: Pulsed Doppler ultrasound was used to evaluate portal blood flow, portal velocity and portal congestion index in 24 healthy sheep divided into groups (lambs, yearlings and ewes), according to age. Measurements were performed at the 11th right intercostal space using ideal insonation angle and uniform insonation method. Mean values obtained in each group were compared with one-way ANOVA, followed by Tukey post-hoc test. Portal velocity and portal blood flow were statistically similar between the groups (P>0.05). Mean portal velocity were 17.75; 17.13 and 16.75; while mean portal blood flow were 26.65; 31.04 and 24.32 for lambs, yearlings and ewes, respectively. Portal congestion index was statistically distinct between the groups and values for lambs, yearlings and ewes were 0.009; 0.058 and 0.09, respectively (P<0.01). Statistical differences were observed in portal vein diameter, portal vein area and portal congestion index between the groups, presumably due to influence of weight and not to age.

Blood flow, volume, and transit time in the pulmonary microvasculature using laser-Doppler

1994 ◽  
Vol 76 (6) ◽  
pp. 2643-2650 ◽  
Author(s):  
T. S. Hakim ◽  
E. Gilbert ◽  
E. M. Camporesi
Keyword(s):  
Blood Flow ◽  
Blood Volume ◽  
Transit Time ◽  
Flow Rate ◽  
Venous Pressure ◽  
Laser Doppler ◽  
Flow Volume ◽  
Doppler Flowmetry ◽  
Blood Flow Volume ◽  
Wide Range

Capillary transit time is determined by the ratio of capillary volume to flow rate. Exercise-induced hypoxemia is thought to occur because of the short transit time of erythrocytes in capillaries. The effect of flow rate on capillary volume (recruitment vs. distension) is controversial. In a perfused left lower lobe preparation in canine lungs, we used laser-Doppler flowmetry (model ALF21R) to monitor changes in blood flow, volume, and transit time in the microvasculature near the subpleural surface. Changes in total flow, blood volume, and total transit time (tt) were also measured. The results showed that microvascular volume approached maximum when flow rate was at resting value (0.4 l/min) and pressure in the pulmonary artery was > 6 mmHg relative to the level of the capillaries. In contrast, the total blood volume increased gradually over a wide range of flow rates. When flow increased 4.2 times (from 155 to 650 ml/min), tt decreased from 7.32 to 3.53 s; meanwhile, microvascular flow increased from 6.0 to 12.7 units and microvascular transit time decreased from 3.14 to 1.81 units. The changes in microvascular volume and transit time were essentially independent of whether the venous pressure was higher or lower than alveolar pressure. At very high flow (6–10 times resting value), tt fell gradually to approximately 1 s. Direct monitoring of transit time with the laser-Doppler also revealed a gradual decline in microvascular transit time as flow rate increased from 2 to 10 times the normal flow. (ABSTRACT TRUNCATED AT 250 WORDS)

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