Microvascular pressures measured by micropipettes in isolated edematous rabbit lungs

1986 ◽  
Vol 60 (2) ◽  
pp. 539-545 ◽  
Author(s):  
J. U. Raj ◽  
R. D. Bland ◽  
S. J. Lai-Fook
Keyword(s):  
Blood Flow ◽  
Vascular Resistance ◽  
Weight Ratio ◽  
Dry Weight ◽  
Pressure Profile ◽  
Longitudinal Distribution ◽  
Lung Edema ◽  
Group Iii ◽  
Group I ◽  
Group Ii

To study the mechanical effects of lung edema on the pulmonary circulation, we determined the longitudinal distribution of vascular resistance in the arteries, veins, and microvessels, and the distribution of blood flow in isolated blood-perfused rabbit lungs with varying degrees of edema. Active vasomotor changes were eliminated by adding papaverine to the perfusate. In three groups of lungs with either minimal [group I, mean wet-to-dry weight ratio (W/D) = 5.3 +/- 0.6 (SD), n = 7], moderate (group II, W/D = 8.5 +/- 1.2, n = 10), or severe (group III, W/D = 9.9 +/- 1.6, n = 5) edema, we measured by direct micropuncture the pressure in subpleural arterioles and venules (20–60 micron diam) and in the interstitium surrounding these vessels. We also measured pulmonary arterial and left atrial pressures and lung blood flow, and in four additional experiments we used radio-labeled microspheres to determine the distribution of blood flow during mild and severe pulmonary edema. In lungs with little or no edema (group I) we found that 33% of total vascular pressure drop was in arteries, 60% was in microvessels, and 7% was in veins. Moderate edema (group II) had no effect on total vascular resistance or on the vascular pressure profile, but severe edema (group III) did increase vascular resistance without changing the longitudinal distribution of vascular resistance in the subpleural microcirculation. Perivascular interstitial pressure relative to pleural pressure increased from 1 cmH2O in group I to 2 in group II to 4 in group III lungs.(ABSTRACT TRUNCATED AT 250 WORDS)

Permeability edema in dog lung depleted of blood components

1984 ◽  
Vol 57 (1) ◽  
pp. 147-153 ◽  
Author(s):  
W. F. Hofman ◽  
I. C. Ehrhart
Keyword(s):  
Average Rate ◽  
Weight Ratio ◽  
Dry Weight ◽  
Left Lobe ◽  
Blood Components ◽  
Fluid Exchange ◽  
Lung Lobe ◽  
Group Iii ◽  
Group I ◽  
Group Ii

We perfused the isolated dog lung lobe with a 6% dextran (mol wt 60,000–90,000) balanced salt solution to determine the importance of blood components in lung fluid balance following injury with oleic acid (OA). The ventilated lower left lobe (LLL) was perfused at constant vascular pressure and weighed continuously as an index of transvascular fluid exchange. Each LLL was washed out with at least 600 ml of perfusate before recirculation started. All LLLs perfused with 6% dextran ion solution (group I) rapidly developed a permeability edema. The addition of 10% serum (vol/vol) from the lobedonor to the 6% dextran ion solution greatly improved LLL stability. One group of dextran-serum perfused LLLs (group II, n = 6, control) was infused with 2.0 ml normal saline; a second group (group III;n = 5) was given 45 microliters/kg body wt OA. Group II showed a linear rate of weight gain that averaged 7.9 g X h-1 X 100 g-1 over 3 h compared with an average rate of 249 g X h-1 X 100 g-1 in groupIII. In contrast to no change in group II, group III exhibited a decline in PO2 (P less than 0.05), andlobar compliance (P less than 0.05) and airway fluid was evident in all lobes by 0.5 h after infusion. The wet-to-dry weight ratio was higher in group III than group II. In the near absence of blood,massive edema developed rapidly following OA. Thus normal blood components, such as platelets, leukocytes, and fibrin do not appear to be essential mediators of OA-induced permeability edema. OA appearsto increase vascular permeability either by injuring the lung directly or by releasing mediators endogenous to lung tissue.

Albumin attenuation of oleic acid edema in dog lung depleted of blood components

1985 ◽  
Vol 58 (6) ◽  
pp. 1949-1955 ◽  
Author(s):  
W. F. Hofman ◽  
I. C. Ehrhart
Keyword(s):  
Oleic Acid ◽  
Weight Gain ◽  
Weight Ratio ◽  
Dry Weight ◽  
Left Lobe ◽  
Albumin Solution ◽  
Lung Lobe ◽  
Group Iii ◽  
Group I ◽  
Group Ii

Circulating fatty acids are normally transported principally bound to serum albumin. We examined whether administering oleic acid (OA) in a concentrated albumin solution would attenuate its edemogenic potential in the isolated dog lung lobe perfused with a solution nearly depleted of blood cellular and protein components. The isolated ventilated lower left lobe (LLL) was perfused (7.3 +/- 0.6 ml X min-1 X g LLL-1) with a balanced salt solution containing 6% dextran and approximately 10% serum (vol/vol). Hourly weight gain, net LLL weight gain, and wet-to-dry weight ratio (W/D) were used as indices of extravascular lung fluid changes. Group I lobes (n = 5) were given saline, whereas both group II (n = 5) and III (n = 5) lobes were administered 1 microliter OA/kg body wt. The OA was incubated with 5 ml of albumin solution containing approximately 640 mg of bovine fatty acid-free albumin before infusion into group III lobes. Group I gained weight at rate of 10.8 +/- 0.5 g X h-1 X 100 g LLL-1 after saline, whereas group II exhibited a greater (P less than 0.005) rate of weight gain of 42 +/- 13 after OA. Group III weight gain of 8.4 +/- 0.5 g X h-1 X 100 g LLL-1 was not different (P greater than 0.05) from group I but was lower (P less than 0.005) than group II.

scholarly journals Different Bleeding Patterns with the Use of Levonorgestrel Intrauterine System: Are They Associated with Changes in Uterine Artery Blood Flow?

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Carlo Bastianelli ◽  
Manuela Farris ◽  
Stefania Rapiti ◽  
Roberta Bruno Vecchio ◽  
Giuseppe Benagiano
Keyword(s):  
Blood Flow ◽  
Uterine Artery ◽  
Endometrial Thickness ◽  
Power Doppler ◽  
Artery Blood Flow ◽  
Group Iii ◽  
Group I ◽  
Significant Difference ◽  
Before And After ◽  
Group Ii

Objective. Evaluate if different bleeding patterns associated with the use of the levonorgestrel intrauterine system (LNG-IUS) are associated with different uterine and endometrial vascularization patterns, as evidenced by ultrasound power Doppler analysis.Methodology. A longitudinal study, with each subject acting as its own control was conducted between January 2010 and December 2012. Healthy volunteers with a history of heavy but cyclic and regular menstrual cycles were enrolled in the study. Ultrasonographic examination was performed before and after six months of LNG-IUS placement: uterine volume, endometrial thickness, and subendometrial and myometrial Doppler blood flow patterns have been evaluated.Results. A total of 32 women were enrolled out of 186 initially screened. At six months of follow-up, all subjects showed a reduction in menstrual blood loss; for analysis, they were retrospectively divided into 3 groups: normal cycling women (Group I), amenorrheic women (Group II), and women with prolonged bleedings (Group III). Intergroup analysis documented a statistically significant difference in endometrial thickness among the three groups; in addition, mean pulsatility index (PI) and resistance index (RI) in the spiral arteries were significantly lower in Group I and Group III compared to Group II. This difference persisted also when comparing—within subjects of Group III—mean PI and RI mean values before and after insertion.Conclusions. The LNG-IUS not only altered endometrial thickness, but—in women with prolonged bleedings—also significantly changed uterine artery blood flow. Further studies are needed to confirm these results and enable gynecologists to properly counsel women, improving initial continuation rates.

LOSS OF WEIGHT AND LIPID SHIFTS IN ORGANS OF THE DIGESTIVE TRACT OF TUMOR-BEARING RATS IN RELATION TO TUMOR SIZE

1960 ◽  
Vol 38 (7) ◽  
pp. 673-681
Author(s):  
Carl E. Boyd ◽  
Eldon M. Boyd ◽  
Audrey A. Deyette
Keyword(s):  
Small Bowel ◽  
Digestive Tract ◽  
Tumor Size ◽  
Dry Weight ◽  
Water Levels ◽  
Group Iii ◽  
Group I ◽  
Loss Of Weight ◽  
Group Ii ◽  
Pyloric Stomach

The objective of this project was to find to what extent loss of weight in the digestive tract might affect tumor size and age in albino rats bearing Walker carcinosarcoma 256. Wet weight, dry weight, and water content were measured upon tongue, esophagus, cardiac stomach, pyloric stomach, jejunum, ileum, cecum, colon, and residual carcass (minus tumor). The animals bore tumors weighing 12 ± 6 (mean ± S.D.) % of host (minus tumor) weight after 18 ± 6 days of tumor growth (group I), 38 ± 12% after 24 ± 6 days (group II), and 93 ± 26% after 29 ± 5 days (group III) and controls were twins of the same sex. There were few significant changes in the animals of group I. In group II, there was loss of dry weight in all organs except pyloric stomach, losses being percentagewise the same as in residual carcass. Loss of dry weight of jejunum and ileum was less in rats of group III than in those of group II. In group III, loss of weight in other organs tended to be less than in residual carcass. Loss of dry weight in residual carcass was not significantly greater in the animals of group III than in those of group II. Water levels were increased in all organs of rats in groups II and III. This evidence indicates that rats of group III may have lived longer after tumor implantation, lost no more carcass weight, and bore larger tumors because they had lost weight in the small bowel at a lesser rate than had the rats of group II.Further studies revealed that lipid shifts were in general less marked in organs which had lost the least weight. In animals bearing large tumors, percentage loss of neutral fat was less in most organs of the digestive tract than in the residual carcass. Increases in the levels of cholesterol and phospholipid were less in pyloric stomach and small bowel than in other organs of the digestive tract. Shifts in the amount of nonlipid dry weight and in levels of lipids and water were in general less in pyloric stomach and small bowel than in other organs of the body. In these respects, pyloric stomach and small bowel resembled brain, heart, and lung. It is suggested that resistance of pyloric stomach and small bowel to the cachectic influence of the tumor may be a factor determining tumor size and length of survival of the host.

Effect of norepinephrine on diaphragm contractility and blood flow

1990 ◽  
Vol 69 (6) ◽  
pp. 2019-2028 ◽  
Author(s):  
G. S. Supinski ◽  
A. F. DiMarco ◽  
J. Gonzalez ◽  
M. D. Altose
Keyword(s):  
Blood Flow ◽  
Group Iv ◽  
Arterial Flow ◽  
Force Frequency ◽  
Group Iii ◽  
Arterial Blood ◽  
Group I ◽  
Intramuscular Electrodes ◽  
Phrenic Artery ◽  
Group Ii

Recent studies have shown that diaphragm fatigue can be reversed by mechanical augmentation of phrenic arterial flow. The purpose of the present experiment was to determine whether it was possible to pharmacologically augment diaphragm blood flow and reverse fatigue by the administration of norepinephrine. Four groups of studies were performed, all employing our previously described in situ isometric canine diaphragm strip preparation (Supinski et al., J. Appl. Physiol. 60: 1789-1796, 1986). Group I studies examined the effects of norepinephrine on the contractility of the nonfatigued diaphragm in normotensive dogs, group II studies examined the effects of this drug on the contractility of the fatigued diaphragm in normotensive animals, and group III studies examined the effect of this drug on the contractility of the fatigued diaphragm in hypotensive animals. Group IV studies examined the effect of norepinephrine in normotensive animals in which the phrenic artery was cannulated and pump perfused at constant flow. Fatigue was induced in group II, III, and IV studies by rhythmically stimulating the diaphragm via intramuscular electrodes. Norepinephrine had no effect on the contractility of the nonfatigued diaphragm (group I). In normotensive (group II) and hypotensive animals (group III), norepinephrine elicited dramatic increases in arterial blood pressure and phrenic arterial flow and produced a significant upshift in the force-frequency curve of the fatigued diaphragm. However, when phrenic flow was held constant (group IV experiments), norepinephrine failed to augment the contractility of the fatigued diaphragm. These results indicate that 1) norepinephrine can increase phrenic blood flow and augment the contractility of the fatigued diaphragm in both normotensive and hypotensive conditions and 2) this effect of norepinephrine to partially reverse fatigue is secondary to its action to augment diaphragmatic blood flow.

Effects of nitroglycerin on forearm haemodynamics in patients with cirrhosis

1988 ◽  
Vol 74 (4) ◽  
pp. 433-436 ◽  
Author(s):  
M. Isabel Jiron ◽  
Samuel S. Lee ◽  
Raimondo Cerini ◽  
Domenico Pugliese ◽  
Antoine Hadengue ◽  
...  
Keyword(s):  
Blood Flow ◽  
Forearm Blood Flow ◽  
Inverse Correlation ◽  
Venous Occlusion ◽  
Group Iii ◽  
Dilatory Response ◽  
Age Related ◽  
Group I ◽  
Venous Distensibility ◽  
Group Ii

1. Basal forearm haemodynamics were studied by venous occlusion plethysmography in three groups of subjects: group I, healthy controls, group II, patients with cirrhosis age- and sex-matched with group I, and group III, an older group of patients with cirrhosis. Subsequently, responses to sublingual nitroglycerin were measured in group I and II subjects. 2. Controls responded to nitroglycerin with an increase in venous distensibility; group II patients had higher initial venous distensibility but did not respond to nitroglycerin. No other variables in either group were affected by nitroglycerin. 3. Group II and III patients differed in forearm blood flow and vascular resistance and venous distensibility. A significant inverse correlation was found between age and forearm blood flow (r = −0.57, P < 0.001) in all patients with cirrhosis. 4. We conclude that (a) venous tone is reduced in cirrhosis, possibly as a result of chronic venodilatation; (b) this venodilatation impedes further dilatory response to a small dose of nitroglycerin; (c) cirrhosis is also associated with age-related decreases in peripheral haemodynamics.

Treatment and Prevention of Diaphragm Fatigue Using Low-Dose Dopamine

2002 ◽  
Vol 3 (3) ◽  
pp. 140-149 ◽  
Author(s):  
Janet D. Pierce ◽  
Richard L. Clancy ◽  
Nan Smith-Blair ◽  
Robert Kraft
Keyword(s):  
Blood Flow ◽  
Intensive Care ◽  
Intensive Care Units ◽  
Low Dose ◽  
Aortic Blood Flow ◽  
Group Iii ◽  
Aortic Blood ◽  
Group I ◽  
Group Ii ◽  
Diaphragm Fatigue

There is increasing evidence that diaphragm fatigue is a major cause of failure in weaning patients frommechanical ventilation. Patients in intensive care units are often administered dopamine to improve renal blood flow without regard to its effect on diaphragmblood flow. The aimof this study was to investigate if intravenous low-dose dopamine, equivalent to the dose used in intensive care units, can treat and prevent diaphragmfatigue. Diaphragmfatigue was produced in anesthetized rats by inspiratory resistance loading (IRL). The effect on diaphragmshortening, diaphragmblood flow, and aortic blood flow was determined. When diaphragm fatigue was attained, group I was given saline for 30 min while maintaining IRL. At the time of diaphragm fatigue, group II was given low-dose dopamine (2 μg/kg/min) for 30 min while maintaining IRL. In group III, dopamine administration was started before and continued throughout the period of IRL. Administering dopamine after the development of diaphragm fatigue (group II) increased diaphragm performance as measured by increased diaphragmshortening and was accompanied by an increased diaphragmblood flow. Administering dopamine prior to and throughout IRL (group III) prevented diaphragmfatigue. Low-dose dopamine can prevent and/or reverse diaphragmfatigue in rats without a significant change in aortic blood flow. This effect of dopamine may be due to increased oxygen delivery associated with the increased diaphragm blood flow, resulting in less free radical formation and thus less muscle damage.

Lung edema formation following inhalation injury: role of the bronchial blood flow

1991 ◽  
Vol 71 (2) ◽  
pp. 727-734 ◽  
Author(s):  
S. Abdi ◽  
D. N. Herndon ◽  
L. D. Traber ◽  
K. D. Ashley ◽  
J. C. Stothert ◽  
...  
Keyword(s):  
Blood Flow ◽  
Bronchial Artery ◽  
Weight Ratio ◽  
Dry Weight ◽  
Inhalation Injury ◽  
Smoke Inhalation ◽  
Lung Edema ◽  
Edema Formation ◽  
Group 2 ◽  
Group 1

We investigated the contribution of the bronchial blood flow to the lung lymph flow (QL) and lung edema formation after inhalation injury in sheep (n = 18). The animals were equally divided into three groups and chronically prepared by implantation of cardiopulmonary catheters and a flow probe on the common bronchial artery. Groups 1 and 2 sheep were insufflated with 48 breaths of cotton smoke while group 3 received only room air. Just before injury, the bronchial artery of group 2 animals was occluded. The occlusion was maintained for the duration of the 24-h study period. At the end of the investigation, samples of lung were taken for determination of blood-free wet weight-to-dry weight ratio (W/D). Inhalation injury induced a sevenfold increase in QL in group 1 (7 +/- 1 to 50 +/- 9 ml/h; P less than 0.05) but only a threefold increase in group 2 (10 +/- 2 to 28 +/- 7 ml/h; P less than 0.05). The mean W/D value of group 1 animals was 23% higher than that of group 2 (5.1 +/- 0.4 vs. 3.9 +/- 0.2; P less than 0.05). Our data suggest that the bronchial circulation contributes to edema formation in the lung that is often seen after the acute lung injury with smoke inhalation.

LOSS OF WEIGHT AND LIPID SHIFTS IN ORGANS OF THE DIGESTIVE TRACT OF TUMOR-BEARING RATS IN RELATION TO TUMOR SIZE

1960 ◽  
Vol 38 (1) ◽  
pp. 673-681
Author(s):  
Carl E. Boyd ◽  
Eldon M. Boyd ◽  
Audrey A. Deyette
Keyword(s):  
Small Bowel ◽  
Digestive Tract ◽  
Tumor Size ◽  
Dry Weight ◽  
Water Levels ◽  
Group Iii ◽  
Group I ◽  
Loss Of Weight ◽  
Group Ii ◽  
Pyloric Stomach

The objective of this project was to find to what extent loss of weight in the digestive tract might affect tumor size and age in albino rats bearing Walker carcinosarcoma 256. Wet weight, dry weight, and water content were measured upon tongue, esophagus, cardiac stomach, pyloric stomach, jejunum, ileum, cecum, colon, and residual carcass (minus tumor). The animals bore tumors weighing 12 ± 6 (mean ± S.D.) % of host (minus tumor) weight after 18 ± 6 days of tumor growth (group I), 38 ± 12% after 24 ± 6 days (group II), and 93 ± 26% after 29 ± 5 days (group III) and controls were twins of the same sex. There were few significant changes in the animals of group I. In group II, there was loss of dry weight in all organs except pyloric stomach, losses being percentagewise the same as in residual carcass. Loss of dry weight of jejunum and ileum was less in rats of group III than in those of group II. In group III, loss of weight in other organs tended to be less than in residual carcass. Loss of dry weight in residual carcass was not significantly greater in the animals of group III than in those of group II. Water levels were increased in all organs of rats in groups II and III. This evidence indicates that rats of group III may have lived longer after tumor implantation, lost no more carcass weight, and bore larger tumors because they had lost weight in the small bowel at a lesser rate than had the rats of group II.Further studies revealed that lipid shifts were in general less marked in organs which had lost the least weight. In animals bearing large tumors, percentage loss of neutral fat was less in most organs of the digestive tract than in the residual carcass. Increases in the levels of cholesterol and phospholipid were less in pyloric stomach and small bowel than in other organs of the digestive tract. Shifts in the amount of nonlipid dry weight and in levels of lipids and water were in general less in pyloric stomach and small bowel than in other organs of the body. In these respects, pyloric stomach and small bowel resembled brain, heart, and lung. It is suggested that resistance of pyloric stomach and small bowel to the cachectic influence of the tumor may be a factor determining tumor size and length of survival of the host.

Enhanced Platelet Thromboxane Synthesis In Normotensive And Hypertensive Pregnancies With Insufficient Fetal Growth

1981 ◽  
Author(s):  
H C S Wallenburg ◽  
P Rotmans
Keyword(s):  
Blood Flow ◽  
Platelet Aggregation ◽  
Fetal Growth ◽  
Gestational Age ◽  
Control Group ◽  
Group Iii ◽  
Group I ◽  
Group Ii ◽  
Generating System ◽  
Platelet Thromboxane

In normal pregnancy platelet aggregation and blood flow in the uterine arteries could be modulated by the balance between the prostacyclin-generating system in the uterine arterial walls and the thromboxane-generating system in platelets. Since hypertensive pregnancies and pregnancies complicated by insufficient fetal growth are characterized by a diminished uteroplacental blood flow,the present study was performed to investigate platelet thromboxane synthesis in these conditions.Material and methods. The study was performed in a control group of 27 women with uncomplicated pregnancies and adequate-for-gestational age (AGA)infants(group I),23 women with uncomplicated pregnancies but small-for-gestational age(SGA) infants(group II); 18 women with pregnancy-induced hypertension (PIH) and AGA-infants(group III); 16 women with PIH and SGA infants(group V).All women were investigated in the last trimester of pregnancy. Venous blood was obtained in EDTA. Platelet aggregation was induced with thrombin( l I.U./ml final concentration)in platelet-rich plasma, and the amount of malondehyde(MDA)generated was measured spectrophotometrically after reaction with thiobarbituric acid. The amount of MDA is equivalent to that of HHT and a measure of the formation of thromboxane.Results. The amount of MDA (mmol/109 platelets ± S.D.)formed in group I was 5.35±0.8, in group II 6.32± 1.4,in group III 6.3 ± 1.5, and in group IV 6.4 ± 1.8. Groups II, III and IV were not different from each other, but were all significantly higher than group I(p < 0.01).Conclusion. The results indicate that pregnant women with a high incidence of a compromised uterine circulation-normotensive with SGA, hypertensive with AGA or SGA- as a group exhibit a more active platelet thromboxane-synthesis. This might be due to defective production of PGI2 by the uterine arterial wall.

Sign in / Sign up

Export Citation Format

Share Document