scholarly journals Comparative Study of Capillary Filtration Coefficient (Kfc) Determination by a Manual and Automatic Perfusion System. Step by Step Technique Review

2019 ◽  
pp. 901-908
Author(s):  
C.C. Bravo-Reyna ◽  
G. Torres-Villalobos ◽  
N. Aguilar-Blas ◽  
J. Frías-Guillén ◽  
J.R. Guerra-Mora
Keyword(s):  
Arterial Pressure ◽  
Pulmonary Arterial Pressure ◽  
Ischemia Reperfusion ◽  
Venous Pressure ◽  
Filtration Coefficient ◽  
Perfusion System ◽  
Gold Standard Method ◽  
Capillary Filtration ◽  
Capillary Filtration Coefficient ◽  
Pulmonary Arterial

The purpose of calculating the capillary filtration coefficient is to experimentally evaluate edema formation in models of pulmonary ischemia-reperfusion injury. For many years, the obtaining of this coefficient implies a series of manual maneuvers during ex-vivo reperfusion of pulmonary arterial pressure, venous pressure and weight, as well as the calculation of the Kfc formula. Through automation, the calculation of capillary filtration coefficient could be easier and more efficient. To describe an automatic method designed in our laboratory to calculating the capillary filtration coefficient and compare with traditional determination of capillary filtration coefficient as gold standard method. An automatic three valve perfusion system was constructed, commanded by a mastery module connected to a graphical user interface. To test its accuracy, cardiopulmonary blocks of Wistar rats were harvested and distributed in manual (n=8) and automated (n=8) capillary filtration coefficient determination groups. Physiological parameters as pulmonary arterial pressure, pulmonary venous pressure, weight and capillary filtration coefficient were obtained. Results: Capillary filtration coefficient, pulmonary arterial pressure, venous arterial pressure shown no statistical significance difference between the groups. The automated perfusion system for obtaining Kfc was standardized and validated, giving reliable results without biases and making the process more efficient in terms of time and personal staff.

Pancreatic circulation: intrinsic regulation

1982 ◽  
Vol 242 (6) ◽  
pp. G596-G602
Author(s):  
P. R. Kvietys ◽  
J. M. McLendon ◽  
G. B. Bulkley ◽  
M. A. Perry ◽  
D. N. Granger
Keyword(s):  
Blood Flow ◽  
Arterial Pressure ◽  
Vascular Resistance ◽  
Venous Pressure ◽  
Filtration Coefficient ◽  
Pancreatic Blood Flow ◽  
Capillary Filtration ◽  
Pressure Elevation ◽  
Capillary Filtration Coefficient ◽  
Intrinsic Regulation

The purpose of the present study was to characterize the intrinsic mechanisms involved in the regulation of blood flow and oxygenation in the totally isolated, perfused canine pancreas. Arterial pressure, venous outflow pressure, blood flow, arteriovenous oxygen difference, and capillary filtration coefficient were measured during graded arterial pressure reductions and venous pressure elevation. Reductions in arterial pressure caused pancreatic blood flow and vascular resistance to decrease, whereas venous pressure elevation resulted in a decreased blood flow and increased vascular resistance. The reductions in blood flow produced by arterial and venous pressure alterations were associated with increases in oxygen extraction and capillary filtration coefficient. During the same pressure perturbations, oxygen uptake remained constant between blood flows of 40-100 ml.min-1.100 g-1, yet decreased progressively as blood flow was reduced below 40 ml.min-1.100 g-1. Arterial occlusion resulted in a postocclusive reactive hyperemia, the magnitude of which was related to the duration of occlusion. The findings of this study suggest that intrinsic regulation of pancreatic blood flow can be attributed to both metabolic and myogenic mechanisms. Resistance and exchange vessels both appear to play a role in the regulation of oxygen delivery to the pancreatic parenchyma.

Fetal whole-body interstitial compliance, vascular compliance, and capillary filtration coefficient

1984 ◽  
Vol 247 (5) ◽  
pp. R800-R805 ◽  
Author(s):  
R. A. Brace ◽  
P. S. Gold
Keyword(s):  
Venous Pressure ◽  
Isotonic Saline ◽  
Optimization Techniques ◽  
Filtration Coefficient ◽  
Whole Body ◽  
Fetal Sheep ◽  
Mean Values ◽  
Capillary Filtration ◽  
Vascular Compliance ◽  
Capillary Filtration Coefficient

Fluid movements across the capillary wall were studied in chronically catheterized, near-term fetal sheep. We hemorrhaged 15 fetuses and infused isotonic saline in seven fetuses. The average experimental changes in arterial pressure, venous pressure, and blood volume were then analyzed by using mathematical modeling and parameter optimization techniques to estimate mean values for the average whole-body interstitial and vascular compliances of the fetus and for the average whole-body fetal capillary filtration coefficient. After fetal hemorrhage, interstitial compliance averaged 45 ml X mmHg-1 X kg-1 of fetal weight and vascular compliance averaged 3.0 ml X mmHg-1 X kg-1, whereas the capillary filtration coefficient averaged 0.4 ml X min-1 X mmHg-1 X kg-1. For intravenous saline infusions, interstitial compliance averaged 45 ml X mmHg-1 X kg-1, and vascular compliance averaged 3.5 ml X mmHg-1 X kg-1, whereas the capillary filtration coefficient averaged 0.8 ml X min-1 X mmHg-1 X kg-1. These data suggest that the fetus has a high whole-body interstitial compliance and a high capillary filtration coefficient compared with the adult. In addition, it appears that the fetus has the ability to decrease its vascular compliance and capillary surface area after a fetal hemorrhage.

Effect of hypoxia on pulmonary artery pressure of dogs

1964 ◽  
Vol 207 (6) ◽  
pp. 1314-1318 ◽  
Author(s):  
Benson R. Wilcox ◽  
W. Gerald Austen ◽  
Harvey W. Bender
Keyword(s):  
Pulmonary Artery ◽  
Arterial Pressure ◽  
Pulmonary Artery Pressure ◽  
Pulmonary Arterial Pressure ◽  
Venous Pressure ◽  
Artery Pressure ◽  
Pulmonary Vasoconstriction ◽  
Systemic Hypoxia ◽  
Pump Output ◽  
Pulmonary Arterial

The mechanism by which the pulmonary artery pressure rises in response to hypoxia has never been clearly demonstrated. This problem was reinvestigated in experiments utilizing separate pulmonary and systemic perfusion systems. These vascular beds were perfused in such a fashion that a change in pulmonary artery pressure could only result from changes in vasomotor tone. Alveolar-pulmonary vein hypoxia was usually associated with a slight fall in pulmonary artery pressure. Systemic hypoxia resulted in elevation of pulmonary arterial pressure in 10 of the 12 animals tested with a constant-flow and constant-pulmonary venous pressure. In addition, all animals with systemic desaturation showed an increased venous return. When the "cardiac output" (pump output) was increased to match this return, the elevation in pulmonary artery pressure increased. It was concluded that the pulmonary arterial pressure elevation seen with hypoxia is the result of active pulmonary vasoconstriction coupled with an increased pulmonary blood flow.

A New Look at Pulmonary Edema

Physiology ◽  
1986 ◽  
Vol 1 (5) ◽  
pp. 150-153 ◽  
Author(s):  
GA Laine ◽  
SJ Allen ◽  
JP Williams ◽  
J Katz ◽  
JC Gabel ◽  
...  
Keyword(s):  
Arterial Pressure ◽  
Pulmonary Edema ◽  
Critically Ill Patients ◽  
Pulmonary Arterial Pressure ◽  
Venous Pressure ◽  
Colloid Osmotic Pressure ◽  
Fluid Accumulation ◽  
Fatal Complication ◽  
Therapeutic Measures ◽  
Pulmonary Arterial

Fluid accumulation within the lungs is a potentially fatal complication in critically ill patients. Sepsis and increased microvascular permeability are often implicated as the cause. This article shows that edema can be prevented by lowering systemic venous pressure (to permit pulmonary lymph to drain), by lowering pulmonary arterial pressure, and by maintaining plasma colloid osmotic pressure. It points out the importance of understanding the basic physiology behind pulmonary edema and therapeutic measures.

Effect of ANP on circulating blood volume

1989 ◽  
Vol 257 (1) ◽  
pp. R127-R131 ◽  
Author(s):  
E. Sugimoto ◽  
K. Shigemi ◽  
T. Okuno ◽  
T. Yawata ◽  
T. Morimoto
Keyword(s):  
Blood Volume ◽  
Venous Pressure ◽  
Filtration Coefficient ◽  
Whole Body ◽  
Control Group ◽  
Peak Reduction ◽  
Circulating Blood Volume ◽  
Capillary Filtration ◽  
Control Value ◽  
Capillary Filtration Coefficient

The effects of rat atrial natriuretic peptide (rANP) on blood volume (BV) were determined by the continuous measurement of BV, mean arterial pressure (MAP), and central venous pressure (CVP). Immediately after a single-bolus injection of rANP-(1-28), 1 nmol/100 g body wt, in conscious rats, BV began to decrease. Peak reduction of -0.22 +/- 0.03 ml/100 g body wt was reached 14.5 min after the injection. Thereafter, BV levels returned gradually to -0.08 +/- 0.03 ml/100 g body wt compared with the control value. In volume expansion experiment, the nephrectomized, anesthetized rats were divided into two groups: the control group, with only a saline infusion, and the ANP group, with an infusion of saline with rANP (1 nmol/100 g body wt). In the ANP group, increases in BV were not as great, and recovery was threefold faster than that of the control group. In the ANP group, the recovery time of BV to the starting control levels was 8.5 min, and the time constant of recovery was 3.6 +/- 0.3 min-1. The control group times were 25 min and 11.5 +/- 0.8 min-1, respectively. The effective vascular compliances were approximately 2.8 ml.mmHg-1.kg body wt-1 in both groups, and the capillary filtration coefficient was 0.47 ml.mmHg-1.min-1.kg body wt-1 in the ANP group and 0.33 ml.mmHg-1.min-1.kg body wt-1 in the control group. Thus the whole body capillary filtration coefficient was 1.5-fold higher in the ANP group than in the control group. This suggests that ANP may increase the permeability of capillaries.

Lowered pulmonary arterial pressure prevents edema after endotoxin in sheep

1987 ◽  
Vol 63 (3) ◽  
pp. 1008-1011 ◽  
Author(s):  
S. J. Allen ◽  
R. E. Drake ◽  
J. Katz ◽  
J. C. Gabel ◽  
G. A. Laine
Keyword(s):  
Pulmonary Hypertension ◽  
Arterial Pressure ◽  
Pulmonary Arterial Pressure ◽  
Venous Pressure ◽  
Dry Weight ◽  
Base Line ◽  
Capillary Membrane ◽  
Significant Difference ◽  
Pulmonary Arterial ◽  
The Difference

Escherichia coli endotoxin causes increased capillary membrane permeability and increased pulmonary arterial pressure (PAP) in sheep. If the pulmonary hypertension extends to the level of the microvasculature, then the increased microvascular pressure may contribute to the pulmonary edema caused by endotoxin. We tested the hypothesis that reducing the pulmonary hypertension would reduce the amount of edema caused by endotoxin. Twelve sheep were chronically instrumented with catheters to measure PAP, left atrial pressure, and central venous pressure. The sheep were divided into two groups. One group (E) of six sheep received an intravenous infusion of 4 micrograms/kg of E. coli endotoxin. The second group (E + SNP) received the same dose of endotoxin as well as a continuous infusion of sodium nitroprusside (SNP) to reduce PAP. Three hours after the endotoxin infusions, the sheep were terminated and the extravascular fluid-to-blood-free dry weight ratios of the lungs were determined (EVF). The base-line PAP was 17.5 +/- 2.7 mmHg. A two-way analysis of variance demonstrated a significant difference (P less than 0.01) in PAP between the E and E + SNP groups. Although PAP in each group varied as a function of time, the difference between the two groups did not. The mean PAP for the E + SNP group (20.9 +/- 1.5 mmHg) was lower than the E group PAP of 27.3 +/- 2.1 mmHg after the endotoxin spike. Furthermore, the E + SNP group EVF (3.9 +/- 0.2) was significantly less than the EVF of the E group (4.7 +/- 0.5).(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of posture on the capillary filtration rate in the human forearm

1970 ◽  
Vol 48 (6) ◽  
pp. 405-414 ◽  
Author(s):  
P. D. Newberry ◽  
J. M. McDonald ◽  
E. R. Rowe
Keyword(s):  
Filtration Rate ◽  
Room Temperature ◽  
Venous Pressure ◽  
Filtration Coefficient ◽  
Left Forearm ◽  
Capillary Filtration ◽  
Capillary Filtration Coefficient ◽  
Human Forearm ◽  
Capillary Resistance ◽  
Male Subjects

A water-filled plethysmograph of a new design was used to measure the capillary filtration rate in the left forearm of each of six male subjects at a room temperature of 27 °C, in the supine and the seated positions. The adoption of the seated position resulted in a decrease of the capillary filtration rate by an average of 0.050 ± 0.015 S.E. ml/min∙100 ml (p < 0.02) and in an increase of the average threshold venous pressure for capillary filtration from 14 to 26 mm Hg (p < 0.01). This change was associated with an increase in the post-capillary resistance. Adoption of the seated position caused no significant change in the capillary filtration coefficient.

Sign in / Sign up

Export Citation Format

Share Document