Pulmonary lymphatic clearance of 99mTc-DTPA from air spaces during lung inflation and lung injury

1987 ◽  
Vol 63 (3) ◽  
pp. 1136-1141 ◽  
Author(s):  
B. T. Peterson ◽  
L. D. Gray
Keyword(s):  
Blood Flow ◽  
Lung Injury ◽  
Control Group ◽  
Diethylenetriaminepentaacetic Acid ◽  
Lung Inflation ◽  
Control Value ◽  
Average Ratio ◽  
Induce Lung Injury ◽  
Right Pulmonary Artery ◽  
The Right

A total of 22 sheep with lymphatic cannulas were used to determine if 99mTc-labeled diethylenetriaminepentaacetic acid (DTPA) clears directly from the air spaces of the lungs into the lymph vessels. Each sheep was anesthetized and ventilated with an aerosol of the DTPA for 2–5 min, and the DTPA activities in the lymph and plasma were measured every 15 min for 2 h. After the first 45 min, the average ratio of the DTPA in the lymph to that in the plasma (L/P) was 1.03 +/- 0.06 (SD) in the six control experiments and 1.11 +/- 0.05 in the six experiments in which the lungs were inflated with a positive end-expired pressure of 10 cmH2O throughout the study. Direct movement of the DTPA from the air spaces into the lymph was not necessary to account for the DTPA clearance in these experiments because the L/P ratio was not significantly different from 1.0. Eight additional sheep received intravenous infusions of air at 0.2 ml.kg-1.min-1 for 2 h to induce lung injury before depositing the DTPA. In these sheep L/P was 1.53 +/- 0.28, which was significantly higher than the value measured in the control group (P less than 0.01). We considered the possibility that the increased L/P ratio in these sheep could be due to alterations in the distribution of the blood flow to the tissue, but the L/P ratio in four sheep whose distribution of blood flow was altered by inflation of a balloon in the right pulmonary artery was 1.05 +/- 0.10, the same as the control value.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Flow Velocity Profiles in Pulmonary Branch Arteries in Lambs

1995 ◽  
Vol 117 (2) ◽  
pp. 237-241
Author(s):  
H. Katayama ◽  
G. W. Henry ◽  
C. L. Lucas ◽  
B. Ha ◽  
J. I. Ferreiro ◽  
...  
Keyword(s):  
Blood Flow ◽  
Pulmonary Artery ◽  
Pulmonary Arteries ◽  
Maximum Velocity ◽  
Left Pulmonary Artery ◽  
Control Group ◽  
Pulsed Doppler Ultrasound ◽  
Right Pulmonary Artery ◽  
Blood Flow Velocities ◽  
The Right

We studied the detailed profiles of blood flow in the right and left pulmonary arteries using 20 MHz pulsed Doppler ultrasound equipment in a lamb model. Fourteen lambs aged four to six weeks were selected. In six lambs, monocrotaline pyrrole was injected parenterally to create pulmonary hypertension (PH group). Eight other lambs served as unaltered controls (control group). The blood flow velocities were sampled in 1mm increments along the anterior—posterior axis of the branch arteries. The maximum velocity of the forward flow in the left pulmonary artery was higher than that in the right pulmonary artery in the control group (71.7 ± 15.9cm/s vs 60.2 ± 13.5; p < 0.05). The fastest backward flow was located at the posterior position of the vessel in the right pulmonary artery in the control group. No significant bias in location was shown in the left pulmonary artery. Using indices of P90, acceleration time, P90*AcT, the velocity waveforms in the PH group were compared with those in the control group. In the left pulmonary artery, every index in the control group showed a significantly greater value that in the PH group. On the other hand, no significant differences were found between either group in the right pulmonary artery.

Hemodilution during Venous Gas Embolization Improves Gas Exchange, without Altering V̇A/Q̇ or Pulmonary Blood Flow Distributions 

1999 ◽  
Vol 91 (6) ◽  
pp. 1861-1861 ◽  
Author(s):  
Steven Deem ◽  
Steven McKinney ◽  
Nayak L. Polissar ◽  
Richard G. Hedges ◽  
Erik R. Swenson
Keyword(s):  
Blood Flow ◽  
Gas Exchange ◽  
Lung Injury ◽  
Partial Pressure ◽  
Pulmonary Blood Flow ◽  
Flow Distribution ◽  
Arterial Oxygen ◽  
Control Group ◽  
Blood Flow Distribution ◽  
Over Time

Background Isovolemic anemia results in improved gas exchange in rabbits with normal lungs but in relatively poorer gas exchange in rabbits with whole-lung atelectasis. In the current study, the authors characterized the effects of hemodilution on gas exchange in a distinct model of diffuse lung injury: venous gas embolization. Methods Twelve anesthetized rabbits were mechanically ventilated at a fixed rate and volume. Gas embolization was induced by continuous infusion of nitrogen via an internal jugular venous catheter. Serial hemodilution was performed in six rabbits by simultaneous withdrawal of blood and infusion of an equal volume of 6% hetastarch; six rabbits were followed as controls over time. Measurements included hemodynamic parameters and blood gases, ventilation-perfusion (V(A)/Q) distribution (multiple inert gas elimination technique), pulmonary blood flow distribution (fluorescent microspheres), and expired nitric oxide (NO; chemoluminescence). Results Venous gas embolization resulted in a decrease in partial pressure of arterial oxygen (PaO2) and an increase in partial pressure of arterial carbon dioxide (PaCO2), with markedly abnormal overall V(A)/Q distribution and a predominance of high V(A)/Q areas. Pulmonary blood flow distribution was markedly left-skewed, with low-flow areas predominating. Hematocrit decreased from 30+/-1% to 11+/-1% (mean +/- SE) with hemodilution. The alveolar-arterial PO2 (A-aPO2) difference decreased from 375+/-61 mmHg at 30% hematocrit to 218+/-12.8 mmHg at 15% hematocrit, but increased again (301+/-33 mmHg) at 11% hematocrit. In contrast, the A-aPO2 difference increased over time in the control group (P &lt; 0.05 between groups over time). Changes in PaO2 in both groups could be explained in large part by variations in intrapulmonary shunt and mixed venous oxygen saturation (SvO2); however, the improvement in gas exchange with hemodilution was not fully explained by significant changes in V(A)/Q or pulmonary blood flow distributions, as quantitated by the coefficient of variation (CV), fractal dimension, and spatial correlation of blood flow. Expired NO increased with with gas embolization but did not change significantly with time or hemodilution. Conclusions Isovolemic hemodilution results in improved oxygen exchange in rabbits with lung injury induced by gas embolization. The mechanism for this improvement is not clear.

Metabolic CO2 Removal by Dialysis: THAM vs NaOH Infusion

1989 ◽  
Vol 12 (11) ◽  
pp. 720-727 ◽  
Author(s):  
J.P. Gille ◽  
C. Saunier ◽  
F. Schrijen ◽  
D. Hartemann ◽  
B. Tousseul
Keyword(s):  
Blood Flow ◽  
Blood Flow Rate ◽  
Co2 Removal ◽  
Control Value ◽  
New Methods ◽  
Lower Blood ◽  
Acid Base Equilibrium ◽  
Marked Weight ◽  
The Difference ◽  
The Right

New methods of respiratory support are needed to reduce the high mortality rate of acute respiratory failure. To simplify the procedures of extracorporeal CO2 elimination under apneic oxygenation, one approach is to replace the membrane lung by a hemodialyzer and to administer an alkali, since hemodialysis requires a lower blood flow rate than blood-gas exchange. This study compared the effectiveness of trishydroxymethyl aminomethane (THAM) and NaOH in this procedure. Twelve male Anglo-Poitevin dogs (25 to 33 kg) were anesthetized, curarized and mechanically hypoventilated (&Vdot;E = 41% of the control value). After not less than 15 min, a venovenous shunt was used for dialysis with blood flow of 7-10 ml. min.-1kg-1 for at least 8 hours. The dialysate contained no acetate, bicarbonate or lactate, but was alkalinized to a pH of 8-9 by the addition of NaOH. A solution of THAM (0.5 N) was infused into the right heart at the rate of 0.30 ml.min.-1kg-1 in six animals, and NaOH (0.15 N) was infused in the other six at the rate of 0.80 ml.min.-1 kg-1. The injected volumes were compensated for by an equivalent amount of ultrafiltration. Elimination of CO2 (mean †CO2 = 2.3 ml.min.-1kg-1) was the same with both methods and the difference for the electrolytes and acid-base equilibrium was only very small. However, hemolysis was six times greater with NaOH than with THAM. Despite ultrafiltration, a similar marked weight gain was observed from the second hour of the experiment in the NaOH series, but only after 7 hours with THAM. It thus appears that hemodialysis combined with alkalinisation is still too complex a procedure to be safely applied in acute or chronic pulmonary failure

A feedback system to control blood flow in dog lung lobes

1982 ◽  
Vol 53 (6) ◽  
pp. 1650-1652
Author(s):  
R. E. Drake ◽  
D. K. Adcock ◽  
R. L. Scott ◽  
J. C. Gabel
Keyword(s):  
Blood Flow ◽  
Left Lung ◽  
Electromagnetic Flowmeter ◽  
Feedback System ◽  
Relative Magnitude ◽  
Left Lobe ◽  
Lung Lobe ◽  
Flow Signal ◽  
Right Pulmonary Artery ◽  
The Right

We have developed an electromechanical feedback system to control blood flow to the lower left lung lobe of dogs. Blood flow is measured with an electromagnetic flowmeter. The feedback system compares the blood flow signal to an adjustable reference voltage and causes a motor to turn. The direction of motor rotation depends on the relative magnitude of the flow signal and the reference. The motor pushes the plunger of a syringe that is attached to a balloon in the right pulmonary artery. Inflation of the balloon causes increased blood flow to the lower left lobe. We have used the system to control lobe blood flow in three dogs.

scholarly journals Function of the p38MAPK-HSP27 Pathway in Rat Lung Injury Induced by Acute Ischemic Kidney Injury

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Tao Ma ◽  
Xiao Wei Liu ◽  
Zhi Liu
Keyword(s):  
Acute Kidney Injury ◽  
Lung Injury ◽  
Signaling Pathways ◽  
Lung Tissue ◽  
Kidney Injury ◽  
Control Group ◽  
Significant Difference ◽  
Induce Lung Injury ◽  
Group A ◽  
Group B

This study aims to observe the changes and the function of p38MAPK-HSP27 signaling pathways in acute lung injury (ALI) induced by acute ischemic kidney injury in rats. Wistar rats were randomly divided into Group A (control group), Group B (acute kidney injury group), and Group C (acute kidney injury +SB203580). The concentration of protein in BALF, neutrophil counts, PI, W/D; the concentration of TNF-α, IL-6, and IL-1βin plasma and BALF; and the concentrations of MDA and NO in the lung tissue started to increase 2 h after the experiment in Group B, which showed a significant difference compared with those in Groups A and C. The expressions of p-p38MAPK and p-HSP27 in the lung tissue began to increase 2 h after the experiment in Group B, which was different from those in Groups A and C. A significant increase was observed in the F-actin expression in Group B than that in Group A. In Group B, the correlation of cytokine TNF-α, IL-6, and p-p38MAPK in BALF was positive. Acute kidney injury (AKI) induced by bilateral renal arteriovenous clamp closure could activate p38MAPK-HSP27 signaling pathways and induce lung injury, which blocks the p38MAPK-HSP27 signal pathway to reduce the risk of lung injury.

Mechanism by Which a Sustained Inflation Can Worsen Oxygenation in Acute Lung Injury

2004 ◽  
Vol 100 (2) ◽  
pp. 323-330 ◽  
Author(s):  
Guido Musch ◽  
R. Scott Harris ◽  
Marcos F. Vidal Melo ◽  
Kevin R. O’Neill ◽  
J. Dominick H. Layfield ◽  
...  
Keyword(s):  
Blood Flow ◽  
Acute Lung Injury ◽  
Gas Exchange ◽  
Lung Injury ◽  
Pulmonary Blood Flow ◽  
Lung Inflation ◽  
Positron Emission ◽  
Regional Lung Function ◽  
Sustained Inflation ◽  
Physiologic Data

Background Sustained lung inflations (recruitment maneuvers [RMs]) are occasionally used during mechanical ventilation of patients with acute lung injury to restore aeration to atelectatic alveoli. However, RMs do not improve, and may even worsen, gas exchange in a fraction of these patients. In this study, the authors sought to determine the mechanism by which an RM can impair gas exchange in acute lung injury. Methods The authors selected a model of acute lung injury that was unlikely to exhibit sustained recruitment in response to a lung inflation. In five sheep, lung injury was induced by lavage with 0.2% polysorbate 80 in saline. Positron emission tomography and [13N]nitrogen were used to assess regional lung function in dependent, middle, and nondependent lung regions. Physiologic data and positron emission scans were collected before and 5 min after a sustained inflation (continuous positive airway pressure of 50 cm H2O for 30 s). Results All animals showed greater loss of aeration and higher perfusion and shunting blood flow in the dependent region. After the RM, Pao2 decreased in all animals by 35 +/- 22 mmHg (P &lt; 0.05). This decrease in Pao2 was associated with redistribution of pulmonary blood flow from the middle, more aerated region to the dependent, less aerated region (P &lt; 0.05) and with an increase in the fraction of pulmonary blood flow that was shunted in the dependent region (P &lt; 0.05). Neither respiratory compliance nor aeration of the dependent region improved after the RM. Conclusions When a sustained inflation does not restore aeration to atelectatic regions, it can worsen oxygenation by increasing the fraction of pulmonary blood flow that is shunted in nonaerated regions.

scholarly journals A novel experimental porcine model to assess the impact of differential pulmonary blood flow on ischemia–reperfusion injury after unilateral lung transplantation

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Anna Elisabeth Frick ◽  
Michaela Orlitová ◽  
Arno Vanstapel ◽  
Sofie Ordies ◽  
Sandra Claes ◽  
...  
Keyword(s):  
Blood Flow ◽  
Pulmonary Artery ◽  
Lung Transplantation ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Left Lung ◽  
Right Pulmonary Artery ◽  
The Right ◽  
The Impact

Abstract Background Primary graft dysfunction (PGD) remains a major obstacle after lung transplantation. Ischemia–reperfusion injury is a known contributor to the development of PGD following lung transplantation. We developed a novel approach to assess the impact of increased pulmonary blood flow in a large porcine single-left lung transplantation model. Materials Twelve porcine left lung transplants were divided in two groups (n = 6, in low- (LF) and high-flow (HF) group). Donor lungs were stored for 24 h on ice, followed by left lung transplantation. In the HF group, recipient animals were observed for 6 h after reperfusion with partially clamping right pulmonary artery to achieve a higher flow (target flow 40–60% of total cardiac output) to the transplanted lung compared to the LF group, where the right pulmonary artery was not clamped. Results Survival at 6 h was 100% in both groups. Histological, functional and biological assessment did not significantly differ between both groups during the first 6 h of reperfusion. injury was also present in the right native lung and showed signs compatible with the pathophysiological hallmarks of ischemia–reperfusion injury. Conclusions Partial clamping native pulmonary artery in large animal lung transplantation setting to study the impact of low versus high pulmonary flow on the development of ischemia reperfusion is feasible. In our study, differential blood flow had no effect on IRI. However, our findings might impact future studies with extracorporeal devices and represent a specific intra-operative problem during bilateral sequential single-lung transplantation.

Features of hemodynamics of the mother–placenta–fetus system in the first half of pregnancy after the assisted reproductive technologies application

2018 ◽  
pp. 62-66
Author(s):  
L.M. Vygivska ◽  
◽  
I.V. Maidannyk ◽  
O.O. Chorna ◽  
V.F. Oleshko ◽  
...  
Keyword(s):  
Blood Flow ◽  
Pregnant Women ◽  
Doppler Ultrasound ◽  
Uterine Artery ◽  
Umbilical Artery ◽  
Assisted Reproductive Technologies ◽  
Reproductive Technologies ◽  
Control Group ◽  
Uterine Arteries ◽  
The Right

Doppler study is one of the main methods for assessing the condition of placental blood circulation and fetal hemodynamics. Doppler blood flow in the uterine arteries demonstrates the broad capabilities of the method for predicting pregnancy complications such as gestosis, fetal development delay, preterm birth, as well as for diagnosing adverse perinatal consequences. However, there is still no clear opinion about the feasibility of using Doppler as a screening test, as well as about the optimal pregnancy period for this type of study. The objective: is to study the hemodynamic features in pregnant women after assisted reproductive technologies (ART) application in the dynamics of the first part of pregnancy. Materials and methods. 299 pregnant women were examined – the main group included 249 women whose pregnancy occurred as a result of ART application. The control group consisted of 50 pregnant women with spontaneous pregnancy and its physiological course. I group – 94 women with tubal-peritoneal factor of infertility, II group – 87 women with endocrine factor of infertility, III group - 68 women whose infertility was caused by the male factor. Doppler ultrasound examination of the uterine arteries, arteries of the umbilical cord and middle cerebral arteries of the fetus were conducted. Results. It was found that the highest intensity of hemodynamics in the uterine artery basin at 11–12 weeks of gestation was recorded in a group of patients with a physiological course of pregnancy. The systolic-diastolic ratio in the right and left uterine arteries in these patients was 1.9 (1.8–2.7) and 2.1 (1.9–2.6), respectively. In contrast to women in the control group, pregnant women after ART application analyzed indicators were higher (1.6–1.9 times; p<0.0001). The systolic-diastolic ratio in the right uterine artery in III group was 3.0 (2.4–3.5), I group – 3.3 (3.1–3.4). Similar data were obtained analyzing the curves of blood flow rates in the left uterine artery – 2.9 (2.1–3.5) and 3.0 (2.7–3.6), respectively. The highest peripheral resistance, both in the right (3.6 (3.4–3.7) and left (3.5 (3.2–3.8) uterine arteries, was naturally registered in pregnant women of II group. In 36 (72%) patients with uncomplicated course and successful gestation at 11–12 weeks of pregnancy, blood flow was not recorded in the intervellon space. In the vast majority – 50 (73.5%) pregnant women of I group, two types of blood flow were registered in the intervellar space: pulsating arterial and continuous venous. Only in 18 (26.5%) patients of this group the blood flow in intervellon space was not determined. As a result of the obtained data analysis, it was found that at 16-17 weeks of gestation, the highest intensity of blood flow in the uterine artery pool was recorded in the control group. Thus, the systolic-diastolic ratio of the right and left uterine arteries in these subjects was 1.6 (1.5–1.8) and 1.8 (1.6–2.0). In pregnant women of the main group, the indicators were significantly higher (1.2-2.0 times; p<0.0001). The systolic-diastolic ratio in the uterine arteries in group III was 2,1 (1,9–2,6); 2,2 (1,9–2,5), in the II group – 3,1 (2,5–3,3); 2,2 (1,9–2,5), in the I group – 2,6 (2,5–3,2); 2,7 (2,5–2,9). In contrast to the control group, in which the systolic-diastolic ratio in the fetal umbilical artery was 3.4 (3.3–3.5), in III group patients, there was a significantly higher intensity of umbilical blood flow (S/D – 3.3 (3.5–3.6), p=0.03). At the same time, feto-placental hemodynamics in II and I groups patients was characterized by a significant increase in the numerical values of blood flow in the umbilical arteries (S/D – 4.5 (4.4–4.7), p=0.0001 and 3.5 (3.5–3.6), p=0.03, respectively). In patients of the control group, the systolic-diastolic ratio of the middle cerebral artery of the fetus at 16–17 weeks of gestation was 3.4 (3.4–3.5), almost completely coinciding with the same indicator in the umbilical artery (S/D – 3.4 (3.3–3.5). Patients of group III had a higher blood flow intensity, as evidenced by significantly lower (S/D 3.2 (3.1–3.3), compared with the control group (S/D 3.4 (3.4–3.5) absolute values of the systolic-diastolic ratio. An increase in the intensity of blood flow in the fetal medial artery (against the background of increased vascular resistance in the umbilical artery) was also recorded in the group of subjects of group II (S/D – 2.8 (2.7–2.9). High absolute values of systolic-diastolic ratio in the indicated vessel (4.4 (4.3–4.5) were found in the fetuses of the examined group and group, which characterize a significant decrease in the intensity of cerebral blood flow, compared with all the analyzed groups. Conclusions. Thus, the results of the study allow us to attribute Doppler ultrasound to highly informative research methods that make it possible to predict hemodynamic changes in the mother-placenta-fetus system, depending on the type of infertility, take preventive measures and start correction in time. Keywords: pregnancy, assisted reproductive technologies, Doppler ultrasound, uterine arteries, systolic-diastolic ratio.

Physiological and Biochemical Consequences of Exposure of Neonatal Rats to Chronic Hypoxia

2020 ◽  
Vol 8 (10) ◽  
Author(s):  
Basil Ibe ◽  
May Abdallah ◽  
J. Raj
Keyword(s):  
Ventricular Hypertrophy ◽  
Chronic Hypoxia ◽  
Platelet Activating Factor ◽  
Control Group ◽  
Neonatal Rats ◽  
Tlr4 Expression ◽  
Control Value ◽  
The Right ◽  
Human Neonates ◽  
Physiological And Biochemical

We studied effect of chronic hypoxia (CH) on expression of platelet activating factor receptor (PAFR) by neonatal rats (pups). We hypothesized that PAFR antagonist will prevent pulmonary hypertension (PH) in pups exposed to CH. Pups were placed in an air-tight chamber ventilated with 13% oxygen, hypoxia (Hpx) or room air normoxia (Nmx) from 1d to 22d of age. Three groups of pups were studied (each group, n=10-14 pups): Group1, pups in Nmx; Group2, pups in Hpx given 5mg/kg PAFR receptor antagonist, WEB 2170, IP, every other day for 22d, (Hpx+WEB); Group3, pups in Hpx control. Hemotocrit, RV/LV+S, PAF binding, PAF synthesis, and PAFR expression were determined. Hyx control group had 2-fold higher RV/LV+S than Nmx group and PAFR antagonist decreased RV/LV+S to the Nmx control value. Lungs of pups in Hpx expressed more PAFR protein than Hpx+WEB and Nmx groups. Additionally, Hpx increased PAF synthesis and PAFR binding whereas WEB treatment decreased PAFR binding, but produced no difference in PAF synthesis compared to Nmx group. Hpx increased NF-kB p65 and TLR4 expression. WEB treatment abrogated expression or NF-kB p65 and TLR4 proteins. Our findings show that chronic hypoxia induces expression of PAFR, NF-kB p65 and TLR4 by pups’ lungs and suggest that increased PAFR expression may be responsible for the right ventricular hypertrophy and PH. Thus a PAFR antagonist may offer a therapeutic intervention for CH-induced PH in human neonates.

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