Measurement of pulmonary clearance of radioaerosol using a portable sodium iodide probe

1984 ◽  
Vol 57 (6) ◽  
pp. 1908-1912 ◽  
Author(s):  
A. L. Jefferies ◽  
G. Coates ◽  
C. E. Webber ◽  
H. M. O'Brodovich
Keyword(s):  
Oleic Acid ◽  
Gamma Camera ◽  
Sodium Iodide ◽  
Intratracheal Instillation ◽  
Acid Group ◽  
Scintillation Camera ◽  
Pulmonary Clearance ◽  
Capillary Membrane ◽  
The Right ◽  
Alveolar Capillary

To determine whether a portable sodium iodide (NaI) probe could provide a valid measure of the pulmonary half-life (T1/2) of aerosolized technetium-99m-diethylenetriaminepentaacetate (99mTc-DTPA, mol wt = 492) in small chests, we measured pulmonary clearance in rabbits using a gamma-scintillation camera and the portable probe. In 10 experiments the lungs of New Zealand White rabbits were insufflated with aerosolized 99mTc-DTPA (0.6 mum aerodynamic mass median diameter) and then simultaneously imaged with the gamma-camera and the probe positioned over the upper right lung. In an additional 12 experiments, alveolar-capillary membrane permeability was increased by either intratracheal instillation of 0.1 N hydrochloric acid (HCl) or intravenous injection of 100 mg/kg of oleic acid. All animals tolerated the procedure. There was a significant decrease in pulmonary T1/2 in both the HCl group (53.4 +/- 10.4 min, mean +/- SE) and the oleic acid group (14.7 +/- 2.3 min) when compared with control (127.5 +/- 18.1 min). When we compared the T 1/2 of the right lung determined by the gamma-camera with that measured by the probe, the correlation coefficient was 0.95. Potential nonpulmonary contributions to thoracic radioactivity were not significant. We conclude that a portable NaI probe is a valid means of determining T 1/2 of 99mTc-DTPA in small chests when compared with a gamma-camera and can detect increases in the permeability of the alveolar-capillary membrane to small solutes.

Gamma camera detection of oleic acid alveolar-capillary albumin leak

1980 ◽  
Vol 29 (1) ◽  
pp. 93-99 ◽  
Author(s):  
Harvey J. Sugerman ◽  
Jerry I. Hirsch ◽  
Alfred M. Strash ◽  
Philip T. Kan ◽  
Alton R. Sharpe ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Gamma Camera ◽  
Alveolar Capillary

Factors affecting perfusion distribution in canine oleic acid pulmonary edema

1986 ◽  
Vol 60 (5) ◽  
pp. 1498-1503 ◽  
Author(s):  
J. Ali ◽  
L. D. Wood
Keyword(s):  
Oleic Acid ◽  
Pulmonary Edema ◽  
Venous Blood ◽  
Lower Lobe ◽  
Acid Group ◽  
Left Lower Lobe ◽  
Base Line ◽  
Positive End Expiratory Pressure ◽  
Vascular Effects ◽  
Factors Affecting

Factors affecting perfusion distribution in oleic acid pulmonary edema were examined in 28 anesthetized open-chest dogs. Sixteen had unilobar oleic acid edema produced by left lower lobe pulmonary artery infusion of 0.03 ml/kg of oleic acid, and 12 had the same amount of edema produced by left lower lobe endobronchial instillation of hypotonic plasma. Lobar perfusion (determined from flow probes) and lobar shunt (determined from mixed venous and lobar venous blood) were measured at base line, 1.5 h after edema, and 10 min after 10 cmH2O positive end-expiratory pressure (PEEP). Fourteen dogs (8 oleic acid, 6 plasma) received sodium nitroprusside (11.72 +/- 7.10 micrograms X kg-1 X min-1). Total and lobar shunts increased to the same extent in all animals. Lobar perfusion decreased by 49.8 +/- 4.8% without nitroprusside and 34.0 +/- 3.6% with nitroprusside in the oleic acid group, corresponding values being 40.3 +/- 0.8% and 26.4 +/- 1.7% in the hypotonic plasma group. PEEP returned perfusion and shunt to base line. In oleic acid edema, most of the decreased perfusion results from mechanical effects of the edema, a smaller fraction results from other vascular effects of the oleic acid, and approximately 30% is reversible by nitroprusside. PEEP normalizes the perfusion distribution.

Lung and chest wall impedances in the dog in normal range of breathing: effects of pulmonary edema

1992 ◽  
Vol 73 (3) ◽  
pp. 1040-1046 ◽  
Author(s):  
G. M. Barnas ◽  
D. Stamenovic ◽  
K. R. Lutchen
Keyword(s):  
Oleic Acid ◽  
Pulmonary Edema ◽  
Chest Wall ◽  
Mean Airway Pressure ◽  
Normal Range ◽  
Normal Ranges ◽  
Before And After ◽  
Measured Resistance ◽  
The Right ◽  
Severe Pulmonary Edema

We evaluated the effect of pulmonary edema on the frequency (f) and tidal volume (VT) dependences of respiratory system mechanical properties in the normal ranges of breathing. We measured resistance and elastance of the lungs (RL and EL) and chest wall of four anesthetized-paralyzed dogs during sinusoidal volume oscillations at the trachea (50–300 ml, 0.2–2 Hz), delivered at a constant mean airway pressure. Measurements were made before and after severe pulmonary edema was produced by injection of 0.06 ml/kg oleic acid into the right atrium. Chest wall properties were not changed by the injection. Before oleic acid, EL increased slightly with increasing f in each dog but was independent of VT. RL decreased slightly and was independent of VT from 0.2 to 0.4 Hz, but above 0.4 Hz it tended to increase with increasing flow, presumably due to the airway contribution. After oleic acid injection, EL and RL increased greatly. Large negative dependences of EL on VT and of RL on f were also evident, so that EL and RL after oleic acid changed two- and fivefold, respectively, within the ranges of f and VT studied. We conclude that severe pulmonary edema changes lung properties so as to make behavior VT dependent (i.e., nonlinear) and very frequency dependent in the normal range of breathing.

scholarly journals Relationship Between Exhaled Na+ and the Diffusion Capacity of the Lungs for Carbon Monoxide (DLCO) and Alveolar‐Capillary Membrane Conductance in Healthy Humans

2010 ◽  
Vol 24 (S1) ◽  
Author(s):  
Courtney M. Wheatley ◽  
Nicholas A. Cassuto ◽  
William T. Foxx‐Lupo ◽  
Eric C. Wong ◽  
Nicholas A. Delamere ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Membrane Conductance ◽  
Diffusion Capacity ◽  
Healthy Humans ◽  
Capillary Membrane ◽  
Alveolar Capillary

scholarly journals Relationship of Structural to Functional Impairment during Alveolar-Capillary Membrane Development

2015 ◽  
Vol 185 (4) ◽  
pp. 913-919 ◽  
Author(s):  
Shawn K. Ahlfeld ◽  
Yong Gao ◽  
Simon J. Conway ◽  
Robert S. Tepper
Keyword(s):  
Functional Impairment ◽  
Capillary Membrane ◽  
Membrane Development ◽  
Relationship Of ◽  
Alveolar Capillary

Diffusion Limitation—Montana Style

2011 ◽  
pp. 135-140
Author(s):  
James R. Munis
Keyword(s):  
Transport Process ◽  
Convective Transport ◽  
The Body ◽  
Peripheral Tissue ◽  
Diffusion Limitation ◽  
Capillary Membrane ◽  
Alveolar Capillary

The pathway of oxygen through the body consists of the diffusion of oxygen across the alveolar-capillary membrane and then the peripheral tissue membranes, followed by the convective transport of oxygen in the blood. Any transport process will have its choke points and limitations. In the case of oxygen, the constraints can take 1 of 2 forms, perfusion limitation or diffusion limitation.

The Two Doctors Fick

2011 ◽  
pp. 94-100
Author(s):  
James R. Munis
Keyword(s):  
Cardiac Output ◽  
Steady State ◽  
Transfer Rate ◽  
Dialysis Membrane ◽  
Solute Transfer ◽  
Fick Principle ◽  
Capillary Membrane ◽  
The Difference ◽  
Physical Laws ◽  
Alveolar Capillary

We often confuse the ‘Fick principle’ with ‘Fick's law of diffusion.’ They are not the same. Ironically, Fick borrowed heavily from already known physical laws when he first described both his law of diffusion and his principle. Borrowing from Ohm's law of electricity, Fick applied concepts of diffusion and transfer across a resistance to formulate a law of diffusion that could be applied to gas or solute transfer across a membrane. Whether we are talking about transfer across the alveolar-capillary membrane or across a dialysis membrane, the concept is the same. The concept is similar to electricity—you have a transfer rate, resistance, and a gradient. Now let's consider the Fick principle. On the basis of another physical law he understood that, in the steady state, the difference between the amount of oxygen going into a tissue bed minus that leaving the tissue bed must be equal to the oxygen consumed. With a little reworking, this became the Fick principle: Cardiac output = O2 consumption / (arterial O2 - venous O2).

Pulmonary clearance of 99mTc-DTPA: influence of background activity

1988 ◽  
Vol 64 (3) ◽  
pp. 1045-1049 ◽  
Author(s):  
M. P. Barrowcliffe ◽  
C. Otto ◽  
J. G. Jones
Keyword(s):  
Background Activity ◽  
Left Lung ◽  
Scintillation Detectors ◽  
Half Time ◽  
Left Chest ◽  
Tissue Accumulation ◽  
Pulmonary Clearance ◽  
Significant Difference ◽  
Left And Right ◽  
The Right

We examined the effect of intravascular and tissue accumulation of tracer when measuring pulmonary clearance of sodium pertechnetate-labeled diethylenetriamine pentaacetate (99mTc-DTPA). Pigs were intubated with endobronchial tubes, permitting deposition of an aerosol of 99mTc-DTPA only into the left lung. Scintillation detectors recorded radioactivity separately from one thigh and from the lung and chest wall on the left and right side. 99mTc-DTPA was given intravenously after 30 min, so that the chest counts from the left lung could be corrected for background activity in either the right lung or the thigh. The uncorrected clearance half time (t1/2) mean± SE from the left chest was 118.5 ± 14.4 min. When corrected for background activity in the right chest, the t1/2 was 82.1 ± 10.5 min, and when corrected for background activity in the thigh, the t1/2 was 80.9 ± 10.6 min. There was no significant difference between t1/2 corrected by the measurements from the right chest or the thigh, and in four of five animals the corrected t1/2 by either method was significantly different from the uncorrected t1/2 (P less than 0.05). There was no correlation between the uncorrected t1/2 and the magnitude of the required correction. We conclude that correction for intravascular and tissue accumulation of tracer is an important refinement of the technique and can easily be accomplished by measuring accumulation of tracer in the thigh.

Inhibitory effect of ileal oleate on postprandial motility of the upper gut

1991 ◽  
Vol 261 (3) ◽  
pp. G458-G463 ◽  
Author(s):  
Z. Dreznik ◽  
D. Brocksmith ◽  
T. A. Meininger ◽  
N. J. Soper
Keyword(s):  
Oleic Acid ◽  
Gastric Emptying ◽  
Gamma Camera ◽  
Delayed Gastric Emptying ◽  
Early Period ◽  
Inhibitory Effect ◽  
Myoelectric Activity ◽  
Phenol Red ◽  
Mixed Meal ◽  
Postprandial Motility

To determine the effect of ileal oleate on postprandial gastrointestinal motility, duodenal and paired perfusion-aspiration ileal catheters and bipolar duodenal and jejunal electrodes were surgically implanted in five dogs. The ileum was perfused with either saline or an isotonic oleic acid emulsion at 2 ml/min. A 205-kcal mixed meal containing 120 ml liquid nutrient labeled with 111In-diethylenetriamine pentaacetic acid (DTPA) and solid food labeled with 99mTc was then administered orally. Gastric emptying was assessed by a gamma camera, myoelectric activity was continuously monitored, and duodenal-ileal transit of phenol red was determined over the ensuing 240 min. Ileal oleate reduced duodenal spikeburst frequency by 50% (P less than 0.05) and delayed gastric emptying of liquids and solids. Four hours after ingesting the meal, 62% of solids and 34% of liquids were retained in the stomach during oleic acid perfusion compared with 25 and 4%, respectively, when saline was perfused (P less than 0.05). Duodenal-ileal transit was markedly slowed by ileal perfusion with the oleic acid emulsion (P less than 0.001). Ileal oleate therefore exerted a profound inhibitory effect on proximal gut motility in the early period after ingestion of a mixed-nutrient meal in dogs.

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