Ventilatory responses to lung inflation and arterial CO2 in halothane-anesthetized dogs

1988 ◽  
Vol 64 (4) ◽  
pp. 1433-1438 ◽  
Author(s):  
G. S. Mitchell ◽  
B. D. Selby
Keyword(s):  
Left Lung ◽  
Surgical Removal ◽  
Halothane Anesthesia ◽  
Burst Frequency ◽  
Lung Inflation ◽  
Arterial Pco2 ◽  
Ventilatory Responses ◽  
Carotid Bodies ◽  
Anesthetized Dogs ◽  
The Right

Hypercapnia attenuates the effects of static airway pressure (Paw) on phrenic burst frequency (f) and the expiratory duration (TE) in chloralose-urethan-anesthetized dogs. Surgical removal of the carotid bodies abolishes this interaction. Since halothane anesthesia in hyperoxia greatly impairs peripheral chemoreflexes, experiments were conducted to determine whether hypercapnia would attenuate the effects of Paw on f and TE in halothane-anesthetized dogs (approximately 1.5 minimum alveolar concentration). Integrated activity of the phrenic nerve was monitored as a function of Paw (2-12 cmH2O) in a vascularly isolated left lung at varied levels of arterial PCO2 (PaCO2; 38-80 Torr) controlled by inspired gas concentrations ventilating the denervated but perfused right lung. Halothane was administered only to the right lung. The results were as follows: 1) integrated phrenic amplitude increased with PaCO2 but was unaffected by Paw; 2) f decreased as Paw increased but was not affected by PaCO2; 3) the inspiratory duration (TI) increased as PaCO2 increased but was unaffected by Paw; 4) TE increased as Paw increased but was unaffected by PaCO2; and 5) there was no phrenic response to intravenous sodium cyanide (50-100 micrograms/kg). Thus, unlike chloralose-urethan-anesthetized dogs, hypercapnia does not attenuate the effect of lung inflation on f or TE in halothane-anesthetized dogs. Furthermore, hypercapnia increases TI during halothane anesthesia, an effect found after carotid denervation but not found in intact chloralose-urethan-anesthetized dogs. It is suggested that these differences between chloralose-urethan- and halothane-anesthetized dogs may be due to functional carotid chemoreceptor denervation by halothane.

METASTATIC CHORIOCARCINOMA PRESENTING AS RENAL COLIC AND SKIN LESION – CASE REPORT

2021 ◽  
Vol 74 (7) ◽  
pp. 1763-1766
Author(s):  
Michał Pietrus ◽  
Adrian Czekaj ◽  
Dominik Dziadkowiak ◽  
Krzysztof Ratajczyk ◽  
Maciej Trzciniecki ◽  
...  
Keyword(s):  
Case Report ◽  
Skin Lesion ◽  
Renal Colic ◽  
Left Lung ◽  
Cutaneous Metastasis ◽  
Blood Levels ◽  
Surgical Removal ◽  
Β Hcg ◽  
The Right ◽  
Kidney Metastasis

Choriocarcinoma is a rare malignant disease that is usually associated with a gestational event. Kidney metastasis might be misdiagnosed as renal cell carcinoma or kidney abscess. To the best of our knowledge, only 13 cases of cutaneous metastasis of choriocarcinoma have been reported in the literature so far. We report a case of choriocarcinoma that manifested with multiple metastases to the lung, skin, kidney and brain. Case report: We reported a case of a 37-year-old woman with a history of hydatiform mole, with symptoms of renal colic and abnormal findings on the skin. Chest X-ray revealed visible focal change 80 mm in diameter, located in the left lung area. The CT exposed in both kidneys multiple hypodense foci, 32 mm in size, suggesting multifocal abscesses with disruptions and perforation to paranephric area. Due to the presence of and temporary loss of vision in the right eye head CT was performed revealing metastatic changes in the brain. The diferential diagnosis between renal cancer, lung carcinoma and choriocarcinoma was achieved only after surgical removal skin lesion. This was the first time in our experience with choriocarcinoma. Immunohistochemically, the analysis was positive for beta hCG, cytokeratin AE1/AE, CK 8/18, CD10, EMA, alfa 1-inhibin and negative for protein 63, CD30 and CD117. Serum hCG level was 394590,0 mIU/mL. Conclusions: Choriocarcinoma should be taken into consideration when associated symptoms and significantly elevated blood levels of β-hCG were identified.

Redistribution of pulmonary blood flow during unilateral hypoxia in prone and supine dogs

1998 ◽  
Vol 84 (6) ◽  
pp. 2010-2019 ◽  
Author(s):  
Christopher M. Mann ◽  
Karen B. Domino ◽  
Sten M. Walther ◽  
Robb W. Glenny ◽  
Nayak L. Polissar ◽  
...  
Keyword(s):  
Blood Flow ◽  
Pulmonary Blood Flow ◽  
Regional Distribution ◽  
Left Lung ◽  
Flow Distribution ◽  
Random Order ◽  
Total Flow ◽  
Hypoxic Vasoconstriction ◽  
Anesthetized Dogs ◽  
The Right

We used fluorescent-labeled microspheres in pentobarbital-anesthetized dogs to study the effects of unilateral alveolar hypoxia on the pulmonary blood flow distribution. The left lung was ventilated with inspired O2 fraction of 1.0, 0.09, or 0.03 in random order; the right lung was ventilated with inspired O2 fraction of 1.0. The lungs were removed, cleared of blood, dried at total lung capacity, then cubed to obtain ∼1,500 small pieces of lung (∼1.7 cm3). The coefficient of variation of flow increased ( P < 0.001) in the hypoxic lung but was unchanged in the hyperoxic lung. Most (70–80%) variance in flow in the hyperoxic lung was attributable to structure, in contrast to only 30–40% of the variance in flow in the hypoxic lung ( P < 0.001). When adjusted for the change in total flow to each lung, 90–95% of the variance in the hyperoxic lung was attributable to structure compared with 70–80% in the hypoxic lung ( P < 0.001). The hilar-to-peripheral gradient, adjusted for change in total flow, decreased in the hypoxic lung ( P = 0.005) but did not change in the hyperoxic lung. We conclude that hypoxic vasoconstriction alters the regional distribution of flow in the hypoxic, but not in the hyperoxic, lung.

Pulmonary arterial distension and activity in phrenic nerve of anesthetized dogs

1979 ◽  
Vol 46 (4) ◽  
pp. 625-631 ◽  
Author(s):  
W. O. Kan ◽  
J. R. Ledsome ◽  
C. P. Bolter
Keyword(s):  
Venous Blood ◽  
Pulmonary Arteries ◽  
Left Lung ◽  
Left Pulmonary Artery ◽  
Systemic Arterial Pressure ◽  
Respiratory Drive ◽  
Vagus Nerves ◽  
Anesthetized Dogs ◽  
Pulmonary Arterial ◽  
The Right

In chloralose-anesthetized dogs a constant-flow, right atrium-to-left pulmonary artery, right-heart bypass was created. The right lung root was completely occluded and an isolated pouch of the main pulmonary arteries was perfused with venous blood at controlled nonpulsatile pressures between 10 and 90 Torr. An increase in pulmonary arterial pouch pressure caused an increase in systemic arterial pressure and in respiratory drive. In animals with afferent nerves intact, the increase in respiratory drive was indicated by an increase in the amplitude of the integrated phrenic electroneurogram. In animals with the left vagus nerve cut immediately above the left lung root, the increase in respiratory drive was evident by a shortening of the time of expiration. All responses were abolished by bilateral section of the cervical vagosympathetic trunks. It is concluded that in the preparation described pulmonary arterial distension causes a reflex increase in systemic vascular resistance and in respiratory drive, the afferent path of the reflex being in the vagus nerves.

Carotid chemoreceptors in ventilatory responses to changes in venous CO2 load

1981 ◽  
Vol 51 (6) ◽  
pp. 1398-1403 ◽  
Author(s):  
E. A. Phillipson ◽  
G. Bowes ◽  
E. R. Townsend ◽  
J. Duffin ◽  
J. D. Cooper
Keyword(s):  
Ventilatory Response ◽  
Venous Blood ◽  
Major Influence ◽  
Arterial Pco2 ◽  
Peripheral Venous Blood ◽  
Carotid Chemoreceptors ◽  
Ventilatory Responses ◽  
Carotid Bodies ◽  
Co2 Excretion

We examined the role of the carotid chemoreceptors in the ventilatory response to changes in venous CO2 load in 12 awake sheep using a venovenous extracorporeal perfusion circuit and two carbon dioxide membrane lungs (CDML). Three of the sheep had undergone surgical denervation of the carotid bodies (CBD). In the nine intact sheep, as CO2 was removed from or added to the peripheral venous blood through the CDML under normoxic conditions, there was a linear relationship between the rate of pulmonary CO2 excretion (VCO2) and the resulting rate of ventilation over a VCO2 range of 0--800% of control, so that arterial PCO2 remained close to isocapnic. In contrast, in the three CBD sheep, the ventilatory response to changes in VCO2 was significantly decreased under normoxic conditions, resulting in marked hypercapnia. The results indicate that the carotid chemoreceptors exert a major influence on the ventilatory response to changes in venous CO2 load.

Reflex effects of lung inflation on tracheal volume

1963 ◽  
Vol 18 (4) ◽  
pp. 681-686 ◽  
Author(s):  
J. G. Widdicombe ◽  
J. A. Nadel
Keyword(s):  
Carotid Body ◽  
Artificial Ventilation ◽  
Vagus Nerves ◽  
Right Heart ◽  
Lung Inflation ◽  
Stretch Receptors ◽  
Pulmonary Stretch Receptors ◽  
Anesthetized Dogs ◽  
The Right ◽  
Spontaneously Breathing

Transient lung inflation increased the volume of a bypassed tracheal segment in anesthetized dogs, whether spontaneously breathing or paralyzed and artificially ventilated. The degree of dilation during inflation varied with the state of “tone” of the tracheal muscle and with the inflation volume. Pulmonary denervation caused maintained constriction of the trachea and blocked the dilation during lung inflation. Cooling the cervical vagus nerves to between 7 and 12 C had the same effect. Both of these procedures blocked the Hering-Breuer inflation reflex, but the trachea still constricted following carotid body chemoreceptor stimulation by KCN. In paralyzed dogs, injection of veratrine into the right heart caused tracheal dilation, presumably by stimulating pulmonary stretch receptors. Left heart injection dilated the trachea much less. The former effect was abolished by pulmonary denervation. In anesthetized spontaneously breathing dogs carotid body chemoreceptor stimulation by KCN constricted the trachea; this was followed by increased ventilation and secondary tracheal dilation. Pulmonary denervation or muscular paralysis and artificial ventilation prevented the secondary dilation. These results establish the reflex nature of tracheal dilation during transient lung inflation and suggest that Hering-Breuer stretch receptors are the responsible end organs. Submitted on January 15, 1963

Asymmetrical action of the canine diaphragm after single-lung inflation

2011 ◽  
Vol 110 (6) ◽  
pp. 1519-1525 ◽  
Author(s):  
André De Troyer ◽  
Dimitri Leduc ◽  
Pierre Alain Gevenois ◽  
Matteo Cappello
Keyword(s):  
Radius Of Curvature ◽  
Lung Inflation ◽  
Endotracheal Tubes ◽  
Computed Tomographic ◽  
Airway Opening ◽  
Anesthetized Dogs ◽  
Radiopaque Markers ◽  
Phrenic Nerves ◽  
The Right ◽  
Phrenic Stimulation

Single-lung transplantation (SLT) in patients with emphysema leads to a cranial displacement of the diaphragm on the transplanted side and a shift of the mediastinum toward the transplanted lung. The objective of the present study was to assess the effect of unilateral lung inflation on the mechanics of the diaphragm. Two endotracheal tubes were inserted in the two main stem bronchi of six anesthetized dogs, and radiopaque markers were attached along muscle fibers in the midcostal region of the two halves of the diaphragm. The animals were then placed in a computed tomographic scanner, the left or the right lung was passively inflated, and the phrenic nerves were stimulated while the two endobronchial tubes were occluded. As lung volume increased, the fall in airway opening pressure (ΔPao) in the inflated lung during stimulation decreased markedly, whereas ΔPao in the noninflated lung decreased only moderately ( P < 0.001). Also, the two hemidiaphragms shortened both during relaxation and during phrenic stimulation, but the ipsilateral hemidiaphragm was consistently shorter than the contralateral hemidiaphragm. In addition, the radius of curvature of the ipsilateral hemidiaphragm during stimulation increased, whereas the radius of the contralateral hemidiaphragm remained unchanged. These observations indicate that 1) in the presence of unilateral lung inflation, the respiratory action of the diaphragm is asymmetric; and 2) this asymmetry is primarily determined by the differential effect of inflation on the length and curvature of the two halves of the muscle. These observations also imply that in patients with emphysema, SLT improves the action of the diaphragm on the transplanted side.

Control of ventilation during intravenous CO2 loading in the awake dog

1978 ◽  
Vol 44 (2) ◽  
pp. 311-316 ◽  
Author(s):  
R. W. Stremel ◽  
D. J. Huntsman ◽  
R. Casaburi ◽  
B. J. Whipp ◽  
K. Wasserman
Keyword(s):  
Carotid Artery ◽  
Common Carotid Artery ◽  
Jugular Vein ◽  
Ventilatory Response ◽  
Arterial Pco2 ◽  
Control Of Ventilation ◽  
Ventilatory Responses ◽  
Co2 Sensitivity ◽  
The Mean ◽  
The Right

The ventilatory response to venous CO2 loading and its effect on arterial CO2 tension was determined in five awake dogs. Blood, 200–500 ml/min, was diverted from a catheter in the right common carotid artery through a membrane gas exchanger and returned to the right jugular vein. CO2 loading was accomplished by changing the gas ventilating the gas exchanger from a mixture of 5% CO2 in air to 100% CO2. The ventilatory responses to this procedure were compared with those resulting from increased inspired CO2 concentrations (during which ventilation of the gas exchanger with the air and 5% CO2 mixture continued). The ventilatory response to each form of CO2 loading was computed as deltaVE/deltaPaco9. The mean ventilatory response to airway CO2 loading was 1.61 1/min per Torr PaCO2. The mean response for the venous CO2 loading was significantly higher and not significantly different from “infinite” CO2 sensitivity (i.e., isocapnic response). The results provide further evidence for a CO2-linked hyperpnea, not mediated by significant changes in mean arterial PCO2.

Role of carotid chemoreceptors and pulmonary vagal afferents during helium-oxygen breathing in ponies

1987 ◽  
Vol 62 (3) ◽  
pp. 1020-1027 ◽  
Author(s):  
L. G. Pan ◽  
H. V. Forster ◽  
G. E. Bisgard ◽  
T. F. Lowry ◽  
C. L. Murphy
Keyword(s):  
Treadmill Exercise ◽  
Work Load ◽  
Vagal Afferents ◽  
Breathing Frequency ◽  
Heavy Exercise ◽  
Arterial Pco2 ◽  
Ventilatory Responses ◽  
Oxygen Breathing ◽  
Carotid Bodies

Our purpose was to assess compensatory breathing responses to airway resistance unloading in ponies. We hypothesized that the carotid bodies and hilar nerve afferents, respectively, sense chemical and mechanical changes caused by unloading, hence carotid body-denervated (CBD) and hilar nerve-denervated ponies (HND) might demonstrate greater ventilatory responses when decreasing resistance. At rest and during treadmill exercise, resistance was transiently reduced approximately 40% in five normal, seven CBD, and five HND ponies by breathing gas of 79% He-21% O2 (He-O2). In all groups at rest, He-O2 breathing did not consistently change ventilation (VE), breathing frequency (f), tidal volume (VT), or arterial PCO2 (PaCO2) from room air-breathing levels. During treadmill exercise at 1.8 mph-5% grade in normal and HND ponies, He-O2 breathing did not change PaCO2 but at moderate (6 mph-5% grade), and heavy (8 mph-8% grade) work loads, absolute PaCO2 tended to decrease by 1 min of resistance unloading. delta PaCO2 calculated as room air minus He-O2 breathing levels at 1 min demonstrated significant changes in PaCO2 during exercise resistance unloading (P less than 0.05). No difference between normal and HND ponies was found in exercise delta PaCO2 responses (P greater than 0.10); however, in CBD ponies, the delta PaCO2 during unloading was greater at any given work load (P less than 0.05), suggesting finer regulation of PaCO2 in ponies with intact carotid bodies. During heavy exercise VE and f increased during He-O2 breathing in all three groups of ponies (P less than 0.05), although there were no significant differences between groups (P greater than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of positive end-expiratory pressure on hypoxic pulmonary vasoconstriction in the dog

1990 ◽  
Vol 259 (3) ◽  
pp. H697-H705 ◽  
Author(s):  
K. B. Domino ◽  
M. R. Pinsky
Keyword(s):  
Blood Flow ◽  
Hypoxic Pulmonary Vasoconstriction ◽  
Linear Regression Analysis ◽  
Left Lung ◽  
Vena Cava ◽  
Positive End Expiratory Pressure ◽  
Anesthetized Dogs ◽  
Alveolar Hypoxia ◽  
Lung Blood Flow ◽  
The Right

We studied the effects of uni- and bilateral positive end-expiratory pressure (PEEP) on pulmonary artery pressure-flow (Ppa/Q) relationships during unilateral hypoxia in anesthetized dogs. A bronchial divider was inserted, the right lung was ventilated with 100% O2, and the left lung was ventilated with either 100% O2 (hyperoxia) or a hypoxic gas mixture (hypoxia). Left lung blood flow (QL) and aortic flow (QT) were measured by electromagnetic flow probes. Simultaneous Ppa/Q relations for both lungs, with Q on the ordinate, were obtained by altering QT via an arteriovenous fistula and an inferior vena cava occluder. Ppa/Q slopes (delta Q/delta Ppa) and extrapolated zero-flow Ppa intercepts (Pzf) were obtained by linear regression analysis. Bilateral PEEP increased Pzf for both lungs (P less than 0.01) but did not alter delta Q/delta Ppa of either lung. Unilateral PEEP decreased ipsilateral blood flow (P less than 0.001) and increased Pzf for the ipsilateral lung (P less than 0.05). Left lung PEEP did not affect the slope of the left lung Ppa/Q relationship (delta QL/delta Ppa). Hypoxic ventilation of the left lung decreased QL (P less than 0.001), increased Pzf (P less than 0.05), and decreased delta QL/delta Ppa (P less than 0.001). Neither uni- nor bilateral PEEP altered this flow diversion away from the left lung or the reduction in delta QL/delta Ppa with left lung hypoxia. We conclude that PEEP and alveolar hypoxia increase pulmonary vascular resistance at different loci, such that their effects are additive. A net increase in 10 cmH2O of PEEP does not inhibit the pulmonary vascular response to regional alveolar hypoxia.

Right Ventricle Mass Removal from Tricuspid Valve Apparatus: An Unusual Thromboembolic Complication of Severe Ketoacidosis

2016 ◽  
Vol 19 (2) ◽  
pp. 077
Author(s):  
Ireneusz Haponiuk ◽  
Maciej Chojnicki ◽  
Konrad Paczkowski ◽  
Wojciech Kosiak ◽  
Radosław Jaworski ◽  
...  
Keyword(s):  
Right Ventricle ◽  
Tricuspid Valve ◽  
Mild Hypothermia ◽  
Heart Function ◽  
Thromboembolic Complication ◽  
Surgical Removal ◽  
Unusual Complication ◽  
Type I ◽  
Definitive Therapy ◽  
The Right

The presence of a pathologic mass in the right ventricle (RV) may lead to hemodynamic consequences and to a life-threatening incident of pulmonary embolism. The diagnosis of an unstable thrombus in the right heart chamber usually necessitates intensive treatment to dissolve or remove the pathology. We present a report of an unusual complication of severe ketoacidosis: thrombus in the right ventricle, removed from the tricuspid valve (TV) apparatus. A four-year-old boy was diagnosed with diabetes mellitus (DM) type I de novo. During hospitalization, a 13.9 × 8.4 mm tumor in the RV was found in a routine cardiac ultrasound. The patient was referred for surgical removal of the floating lesion from the RV. The procedure was performed via midline sternotomy with extracorporeal circulation (ECC) and mild hypothermia. Control echocardiography showed complete tumor excision with normal atrioventricular valves and heart function. Surgical removal of the thrombus from the tricuspid valve apparatus was effective, safe, and a definitive therapy for thromboembolic complication of pediatric severe ketoacidosis.<br /><br />

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