Mechanism of arterial hypoxemia following pulmonary thromboembolism in dogs

1975 ◽  
Vol 39 (1) ◽  
pp. 41-46 ◽  
Author(s):  
S. E. Levy ◽  
D. H. Simmons
Keyword(s):  
Pulmonary Thromboembolism ◽  
Minute Volume ◽  
Lung Mechanics ◽  
Diffusing Capacity ◽  
Pulmonary Resistance ◽  
Arterial Hypoxemia ◽  
Single Breath ◽  
Before And After ◽  
Pulmonary Embolization

Mongrel dogs (29) were anesthetized, paralyzed, and ventilated at a constant minute volume. AaD02 breathing air and 100% O2, venous admixture breathing air (Qva/Qt) and 100% O2 (Qs/Qt), single-breath diffusing capacity for CO (DLCO), and total pulmonary resistance (RL) and pulmonary compliance (CL) were measured before and after pulmonary embolization with autologus in vivo venous thrombi. Nine dogs were heparinized before embolization. In the 20 nonheparinized dogs AaDo2 breathing air increased from 11 to 26 mmHg, Qva/Qt from 4 to 22%, and Qs/At from 5 to 8%. DLCO decreased 24%, RL increased 43%, and CL fell 30%. In the nine heparinized dogs AaDo2 breathing air increased from 8 to 13 mmHg and Qva/Qt from 3 to 8%; Qs/Qt did not change. DLCO decreased 31%; RL and CL did not change significantly. The increase in Qva/Qt of 5% in the heparinized dogs was significantly less (P smaller than 0.001) than the increase of 18% in the nonheparinized dogs. These findings suggest that arterial hypoxemia following thromboembolism is due to ventilation-perfusion inequality caused by changes in lung mechanics.

Effects of fever on pulmonary diffusing capacity and pulmonary mechanics in man

1963 ◽  
Vol 18 (6) ◽  
pp. 1065-1070 ◽  
Author(s):  
Leon Cander ◽  
Ernest G. Hanowell
Keyword(s):  
Pulmonary Blood Flow ◽  
Minute Volume ◽  
Lung Mechanics ◽  
Breath Holding ◽  
Pulmonary Mechanics ◽  
Diffusing Capacity ◽  
Oral Temperature ◽  
Pulmonary Resistance ◽  
Pulmonary Diffusing Capacity ◽  
Normal Adults

Measurements of oral temperature, pulse rate, blood pressure, expired minute volume (Ve), respiratory rate (f), O2 consumption (Vo2), CO2 excretion (Vco2), breath-holding pulmonary diffusing capacity (DlCO), dynamic pulmonary compliance (Cdyn), and total pulmonary resistance were made on six normal adults before and at regular intervals over an 8-hr period following the induction of fever with triple typhoid vaccine. Although Ve, f, Vo2 increased during the chill, flush, and defervescence phases of fever, there was no significant change in Cdyn and total pulmonary resistance. Of interest was the slight, though statistically significant decrease in DlCO during the flush and defervescence phases. Results suggest a low temperature coefficient for the mechanical properties of the lung in the range studied. The absence of an increased DlCO during the flush phase of fever when Ve and the cardiac output are known to increase suggests that ventilation and pulmonary blood flow are not important determinants of DlCO. lung mechanics; ventilation Submitted on February 18, 1963

Respiratory mechanics in men following a deep air dive

1986 ◽  
Vol 61 (2) ◽  
pp. 734-740 ◽  
Author(s):  
P. W. Catron ◽  
J. Bertoncini ◽  
R. P. Layton ◽  
M. E. Bradley ◽  
E. T. Flynn
Keyword(s):  
Lung Function ◽  
Vital Capacity ◽  
Respiratory Mechanics ◽  
Decompression Sickness ◽  
Lung Compliance ◽  
Lung Mechanics ◽  
Base Line ◽  
Pulmonary Resistance ◽  
Doppler Signals ◽  
Before And After

The mechanical properties of the lungs were measured in 10 men before and after a simulated air dive to 285 ft of seawater (87 m). The objective was to determine whether a dive likely to produce pulmonary bubble emboli would alter lung mechanics. Lung function was measured predive and at 1, 2, 3, 6, 7, and 23 h postdive. Measurements of lung function were also made at identical times on a control day when no dive was made. Each set of measurements included precordial Doppler signals, pulmonary resistance, quasistatic lung compliance, forced vital capacity (FVC), forced expired volume after 1.0 s (FEV 1.0), the ratio of FEV 1.0 to FVC (FEV 1.0/FVC%), and maximal airflow after 50 and 75% of the vital capacity had been expired (Vmax50 and Vmax75, respectively). Base-line measurements of pulmonary resistance and quasistatic compliance were normal in all subjects. FVC and FEV 1.0 were greater than predicted for most subjects and were increased proportionately so that the FEV 1.0/FVC% was normal. Following the dive, bubble signals were heard in four subjects, and two subjects had mild symptoms of decompression sickness. No subject demonstrated any alteration in lung function that could be attributed to the dive. We concluded that stressful decompressions capable of producing “silent” pulmonary bubble emboli do not alter lung mechanics.

Early exercise pulmonary diffusing capacity of carbon monoxide after anatomical lung resection: a word of caution for fast-track programmes

2019 ◽  
Vol 56 (1) ◽  
pp. 143-149 ◽  
Author(s):  
Nuria M Novoa ◽  
Pedro Esteban ◽  
Maria Teresa Gómez Hernández ◽  
Marta G Fuentes ◽  
Gonzalo Varela ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Visual Analogue Scale ◽  
Analogue Scale ◽  
Lung Resection ◽  
Linear Regression Analysis ◽  
Diffusing Capacity ◽  
Early Exercise ◽  
The Third ◽  
Single Breath ◽  
Before And After

Abstract OBJECTIVES In healthy individuals, increasing pulmonary blood flow during exercise also increases the % of the diffusing capacity of the lungs for carbon monoxide (DLCO%), but its evolution after lung resection is unknown. In this study, our goal was to measure changes in exercise DLCO% during the first 3 days after anatomical lung resection. METHODS We performed a prospective observational study on consecutive patients with non-small-cell lung cancer scheduled for anatomical resection, except pneumonectomy, during a 6-month period. Patients underwent measurement of the DLCO% by a single-breath technique adjusted by the concentration of haemoglobin—before and after standardized exercise the day before and 3 consecutive days after surgery. The delta (Δ) variation (basal versus exercise) was calculated. The number of functioning resected segments was calculated by bronchoscopy. Postoperative pain and pleural air leak were estimated using a visual analogue scale and graduated conventional pleural drainage systems, respectively, and their influence on ΔDLCO each postoperative day was evaluated by linear regression analysis. RESULTS Fifty-seven patients were included. The visual analogue scale of pain and pleural air leaks were not correlated to Δ values (model R2: 0.0048). The evolution of Δ values during 3 postoperative days showed a progressive recovery of values, but on the third day, DLCO% capacity during exercise was still impaired (P < 0.01), especially in patients who underwent a resection of more than 3 functioning segments. CONCLUSIONS Physiological increase in DLCO% during exercise is still impaired on the third postoperative day in patients undergoing resection of more than 3 functioning pulmonary segments. This fact should be considered before discharging those patients after anatomical lung resection.

scholarly journals Significant blood resistance to nitric oxide transfer in the lung

2010 ◽  
Vol 108 (5) ◽  
pp. 1052-1060 ◽  
Author(s):  
Colin D. R. Borland ◽  
Helen Dunningham ◽  
Fiona Bottrill ◽  
Alain Vuylsteke ◽  
Cuneyt Yilmaz ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Exchange Transfusion ◽  
Membrane Conductance ◽  
In Vivo Studies ◽  
Bovine Hemoglobin ◽  
Diffusing Capacity ◽  
Before And After ◽  
Capillary Blood Volume

Lung diffusing capacity for nitric oxide (DlNO) is used to measure alveolar membrane conductance (DmNO), but disagreement remains as to whether DmNO = DlNO, and whether blood conductance (θNO) = ∞. Our previous in vitro and in vivo studies suggested that θNO < ∞. We now show in a membrane oxygenator model perfused with whole blood that addition of a cell-free bovine hemoglobin (Hb) glutamer-200 solution increased diffusing capacity of the circuit (D) for NO (Dno) by 39%, D for carbon monoxide (Dco) by 24%, and the ratio of Dno to Dco by 12% (all P < 0.001). In three anesthetized dogs, DlNO and DlCO were measured by a rebreathing technique before and after three successive equal volume-exchange transfusions with bovine Hb glutamer-200 (10 ml/kg each, total exchange 30 ml/kg). At baseline, DlNO/DlCO = 4.5. After exchange transfusion, DlNO rose 57 ± 16% (mean ± SD, P = 0.02) and DlNO/DlCO = 7.1, whereas DlCO remained unchanged. Thus, in vitro and in vivo data directly demonstrate a finite θNO. We conclude that the erythrocyte and/or its immediate environment imposes considerable resistance to alveolar-capillary NO uptake. DlNO is sensitive to dynamic hematological factors and is not a pure index of conductance of the alveolar tissue membrane. With successive exchange transfusion, the estimated in vivo θNO [5.1 ml NO·(ml blood·min·Torr)−1] approached 4.5 ml NO·(ml blood·min·Torr)−1, which was derived from in vitro measurements by Carlsen and Comroe ( J Gen Physiol 42: 83–107, 1958). Therefore, we suggest use of θNO = 4.5 ml NO·(min·Torr·ml blood)−1 for calculation of DmNO and pulmonary capillary blood volume from DlNO and DlCO.

Diffusing capacity of the lung during hypoxia: role of capillary recruitment

1981 ◽  
Vol 50 (1) ◽  
pp. 165-171 ◽  
Author(s):  
R. L. Capen ◽  
L. P. Latham ◽  
W. W. Wagner
Keyword(s):  
Carbon Monoxide ◽  
Gas Exchange ◽  
Surface Area ◽  
Diffusing Capacity ◽  
Capillary Recruitment ◽  
Pulmonary Capillary ◽  
Hemoglobin Binding ◽  
Before And After

We have used in vivo microscopy to show that airway hypoxia caused pulmonary capillary recruitment. To determine whether the recruited capillaries add to the surface area for gas exchange, we measured the diffusing capacity of the lung for carbon monoxide before and after inducing recruitment with hypoxia. Diffusing capacity increased during hypoxia. However, some increase in diffusing capacity was expected, since there were fewer oxygen molecules to compete with carbon monoxide for hemoglobin-binding sites. To determine the effect of capillary recruitment alone on diffusing capacity, we held hypoxia constant while infusing a vasodilator to diminish recruitment. Diffusing capacity decreased concomitantly as recruitment diminished. These results indicate that our microscopic observations reflect a widespread recruitment that increases the gas exchange surface area.

Influence of Performance Level on Exercise-Induced Arterial Hypoxemia During Prolonged and Successive Exercise in Triathletes

2008 ◽  
Vol 3 (4) ◽  
pp. 482-500 ◽  
Author(s):  
Olivier Galy ◽  
Olivier Hue ◽  
Karim Chamari ◽  
Alain Boussana ◽  
Anis Chaouachi ◽  
...  
Keyword(s):  
Short Distance ◽  
Alveolar Ventilation ◽  
Diffusing Capacity ◽  
Diffusion Limitation ◽  
Arterial Hypoxemia ◽  
Ventilatory Parameters ◽  
Before And After ◽  
Exercise Induced ◽  
And Control ◽  
The Relationship

Purpose:To study the relationship between performance and exercise-induced arterial hypoxemia (EIAH), 5 internationally ranked (INT) and 8 regionally ranked (REG) triathletes performed cycle-run successions (CR) and control runs (R) in competitionlike conditions: at ≍75% VO2max.Methods:Ventilatory parameters and oxyhemoglo-bin saturation (SpO2) data were collected continuously. Arteriolized partial pressure in O2 (PaO2) and alveolar ventilation (VA) were measured before and after cycling (CRcycle), the successive run (CRrun), and R. Pulmonary diffusing capacity (DLco) was measured at rest and 10 minutes post-CR. Training and short-distance triathlon data were collected.Results:INT showed signifcantly greater experience than REG in competition years (P > .05), training regimen (P > .05), and swimming (P > .05), and cycling (P > .05) volumes; running showed a trend (P < .06). Cycling, running, and total triathlon performances were significantly higher in INT than REG (P > .01). SpO2 during CR dropped significantly more in INT than in REG. Both groups showed significant inverse correlations between the magnitude of the SpO2 change from CRcy-cle to CRrun and the triathlon running time (r = −0.784; P < .05 and r = −0.699; P < .05; respectively). When compared with CRcycle, PaO2 significantly decreased and VA significantly increased after CRrun and R in both groups (P < .01). DLco significantly dropped between pre- and postexercise in CR and R with no between-group difference (P < .05).Conclusions:EIAH was aggravated in higher performers during simulated cycle-run segments, related to longer experience and heavier training regimens. Possibly, relative hypoventilation caused this aggravated EIAH in INT, although pulmonary diffusion limitation was observed in both groups. Beyond EIAH severity, the magnitude of SpO2 variations during the cycle-run transition may affect triathlon running performance.

Radiolabeled r-Hirudin as a Measure of Thrombin Activity at, or within, the Rabbit Aorta Wall In Vitro and In Vivo

1994 ◽  
Vol 71 (04) ◽  
pp. 499-506 ◽  
Author(s):  
Mark W C Hatton ◽  
Bonnie Ross-Ouellet
Keyword(s):  
Rabbit Aorta ◽  
Balloon Injury ◽  
Recombinant Hirudin ◽  
Aorta Wall ◽  
Thrombin Activity ◽  
Before And After ◽  
The Matrix

SummaryThe behavior of 125I-labeled recombinant hirudin towards the uninjured and de-endothelialized rabbit aorta wall has been studied in vitro and in vivo to determine its usefulness as an indicator of thrombin activity associated with the aorta wall. Thrombin adsorbed to either sulfopropyl-Sephadex or heparin-Sepharose bound >95% of 125I-r-hirudin and the complex remained bound to the matrix. Binding of 125I-r-hirudin to the exposed aorta subendothelium (intima-media) in vitro was increased substantially if the tissue was pre-treated with thrombin; the quantity of l25I-r-hirudin bound to the de-endothelialized intima-media (i.e. balloon-injured in vitro) correlated positively with the quantity of bound 131I-thrombin (p <0.01). Aortas balloon-injured in vivo were measured for thrombin release from, and binding of 125I-r-hirudin to, the de-endothelialized intimal surface in vitro; 125I-r-hirudin binding correlated with the amount of active thrombin released (p <0.001). Uptake of 125I-r-hirudin by the aorta wall in vivo was proportional to the uptake of 131I-fibrinogen (as an indicator of thrombin activity) before and after balloon injury. After 30 min in the circulation, specific 125I-r-hirudin binding to the uninjured and de-endo- thelialized (at 1.5 h after injury) aorta wall was equivalent to 3.4 (± 2.5) and 25.6 (±18.1) fmol of thrombin/cm2 of intima-media, respectively. Possibly, only hirudin-accessible, glycosaminoglycan-bound thrombin is measured in this way.

The Effect of Active Site-inhibited Factor VIIa on Tissue Factor-initiated Coagulation Using Platelets before and after Aspirin Administration

1997 ◽  
Vol 78 (04) ◽  
pp. 1202-1208 ◽  
Author(s):  
Marianne Kjalke ◽  
Julie A Oliver ◽  
Dougald M Monroe ◽  
Maureane Hoffman ◽  
Mirella Ezban ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Active Site ◽  
Large Scale ◽  
Thrombin Generation ◽  
Factor Viia ◽  
Dependent Manner ◽  
Antithrombotic Agent ◽  
Before And After ◽  
Ic50 Values

SummaryActive site-inactivated factor VIIa has potential as an antithrombotic agent. The effects of D-Phe-L-Phe-L-Arg-chloromethyl ketone-treated factor VIla (FFR-FVIIa) were evaluated in a cell-based system mimicking in vivo initiation of coagulation. FFR-FVIIa inhibited platelet activation (as measured by expression of P-selectin) and subsequent large-scale thrombin generation in a dose-dependent manner with IC50 values of 1.4 ± 0.8 nM (n = 8) and 0.9 ± 0.7 nM (n = 7), respectively. Kd for factor VIIa binding to monocytes ki for FFR-FVIIa competing with factor VIIa were similar (11.4 ± 0.8 pM and 10.6 ± 1.1 pM, respectively), showing that FFR-FVIIa binds to tissue factor in the tenase complex with the same affinity as factor VIIa. Using platelets from volunteers before and after ingestion of aspirin (1.3 g), there were no significant differences in the IC50 values of FFR-FVIIa [after aspirin ingestion, the IC50 values were 1.7 ± 0.9 nM (n = 8) for P-selectin expression, p = 0.37, and 1.4 ± 1.3 nM (n = 7) for thrombin generation, p = 0.38]. This shows that aspirin treatment of platelets does not influence the inhibition of tissue factor-initiated coagulation by FFR-FVIIa, probably because thrombin activation of platelets is not entirely dependent upon expression of thromboxane A2.

Determination and Treatment of Disorders of Primary Haemostasis

1999 ◽  
Vol 19 (04) ◽  
pp. 168-175 ◽  
Author(s):  
M. Weippert-Kretschmer ◽  
V. Kretschmer
Keyword(s):  
Platelet Function ◽  
Bleeding Risk ◽  
Bleeding Complications ◽  
Bleeding Tendency ◽  
Platelet Counts ◽  
Platelet Function Disorders ◽  
Perioperative Bleeding ◽  
Before And After ◽  
Low Sensitivity

SummaryPerioperative bleeding complications due to disorders of primary haemostasis are often underestimated. Routine determination of primary haemostasis is still problematic. The in vivo bleeding time (BT) shows low sensitivity and high variability. In this contribution the results and experiences with the IVBT having been obtained in various studies and during 10 years of routine use are reported. Patients and Methods: Blood donors before and after ASA ingestion, patients with thrombocytopenia as well as congenital and acquired platelet function disorders. Monitoring of desmopressin efficacy. IVBT with Thrombostat 4000 (tests with CaCl2 = TST-CaCl2 and ADP = TST-ADP) and PFA-100 (test cartridges with epinephrine = PFA-EPI and ADP = PFA-ADP). Results and Conclusions: IVBT becomes abnormal with platelet counts <100,000/μl. With platelet counts <50,000/μl the results are mostly outside the methodical range. IVBT proved clearly superior to BT in von Willebrand syndrome (vWS). All 16 patients with vWS were detected by PFA-EPI, whereas with BT 7 of 10 patients with moderate and 1 of 6 patients with mild forms of vWS were spotted. The majority of acquired and congenital platelet function disorders with relevant bleeding tendency were detectable by IVBT. Sometimes diagnostic problems arose in case of storage pool defect. Four to 12 h after ingestion of a single dose of 100 mg ASA the TST-CaCl2 became abnormal in all cases, the PFA-EPI only in 80%. However, the ASA sensitivity of TST-CaCl2 proved even too high when looking for perioperative bleeding complications in an urological study. Therefore, the lower ASS sensitivity of the PFA-100 seems to be rather advantageous for the estimation of a real bleeding risk. The good efficacy of desmopressin in the majority of cases with mild thrombocytopenia, congenital and acquired platelet function disorders and even ASS-induced platelet dysfunction could be proven by means of the IVBT. Thus IVBT may help to increase the reliability of the therapy. However, the IVBT with the PFA-100 is not yet fully developed. Nevertheless, routine use can be recommended when special methodical guidelines are followed.

Аpplying of high-frequency monopolar diathermocoagulation in the treatment of chronic pulpitis

2020 ◽  
Vol 1 (12) ◽  
pp. 40-42
Author(s):  
F. Yu. Daurova ◽  
D. I. Tomaeva ◽  
S. V. Podkopaeva ◽  
Yu. A. Taptun
Keyword(s):  
Root Canal ◽  
High Frequency ◽  
Antibacterial Effect ◽  
Comparison Group ◽  
Poor Quality ◽  
Endodontic Treatment ◽  
Root Canals ◽  
The Third ◽  
Before And After

Relevance: the reason for the development of complications in endodontic treatment is poor-quality instrumental treatment root canals.Aims: a study of the animicrobial action and clinical efficacy of high-frequency monopolar diathermocoagulation in the treatment of chronic forms of pulpitis.Materials and methods: 102 patients with various chronic forms of pulpitis were divided into three groups of 34 patients each. In the first two groups, high-frequency monopolar diathermocoagulation was used in endodontic treatment in different modes. In the third group, endodontic treatment was carried out without the use of diathermocoagulation (comparison group). The root canal microflora in chronic pulpitis in vivo was studied twice-before and after diathermocoagulation.Results: it was established that high-frequency monopolar diathermocoagulation in the effect mode is 3, power is 4 (4.1 W) and effect is 4, power is 4 (5.4 W) with an exposure time of 3 seconds, it has a pronounced antibacterial effect on all presented pathogenic microflora obtained from the root canals of the teeth.

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