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Circulation Jul 2007
Topics: Aspirin; Cardiovascular Diseases; Cardiovascular Surgical Procedures; Humans; Pulmonary Artery; Pulmonary Circulation
PubMed: 17638938
DOI: 10.1161/CIRCULATIONAHA.107.707992 -
Monaldi Archives For Chest Disease =... Dec 1996
Review
Topics: Administration, Inhalation; Animals; Humans; Hypertension, Pulmonary; Hypoxia; Nitric Oxide; Prognosis; Pulmonary Circulation; Rats; Respiratory Distress Syndrome
PubMed: 9046167
DOI: No ID Found -
Cardiology in ReviewAcquiring pulmonary circulation parameters as a potential marker of cardiopulmonary function is not new. Methods to obtain these parameters have been developed over... (Review)
Review
Acquiring pulmonary circulation parameters as a potential marker of cardiopulmonary function is not new. Methods to obtain these parameters have been developed over time, with the latest being first-pass perfusion sequences in cardiovascular magnetic resonance (CMR). Even though more data on these parameters has been recently published, different nomenclature and acquisition methods are used across studies; some works even reported conflicting data. The most commonly used circulation parameters obtained using CMR include pulmonary transit time (PTT) and pulmonary transit beats (PTB). PTT is the time needed for a contrast agent (typically gadolinium-based) to circulate from the right ventricle (RV) to the left ventricle (LV). PTB is the number of cardiac cycles the process takes. Some authors also include corrected heart rate (HR) versions along with standard PTT. Besides other methods, CMR offers an option to assess stress circulation parameters, but data are minimal. This review aims to summarize the up-to-date findings and provide an overview of the latest progress on this promising, dynamically evolving topic.
Topics: Humans; Heart; Magnetic Resonance Imaging; Pulmonary Circulation; Contrast Media; Magnetic Resonance Spectroscopy; Predictive Value of Tests
PubMed: 36728820
DOI: 10.1097/CRD.0000000000000495 -
Minerva Anestesiologica Jun 2005Cardiac output and the pulmonary perfusion can be affected by anesthesia and by mechanical ventilation. The changes contribute to impeded oxygenation of the blood. The... (Review)
Review
Cardiac output and the pulmonary perfusion can be affected by anesthesia and by mechanical ventilation. The changes contribute to impeded oxygenation of the blood. The major determinant of perfusion distribution in the lung is the relation between alveolar and pulmonary capillary pressures. Perfusion increases down the lung, due to hydrostatic forces. Since atelectasis is located in dependent lung regions, perfusion of non-ventilated lung parenchyma is common, producing shunt of around 8-10% of cardiac output. In addition, non-gravitational inhomogeneity of perfusion, that can be greater than the gravitational inhomogeneity, adds to impeded oxygenation of blood. Essentially all anaesthetics exert some, although mild, cardiodepressant action with one exception, ketamine. Ketamine may also increase pulmonary artery pressure, whereas other agents have little effect on pulmonary vascular tone. Mechanical ventilation impedes venous return and pushes blood flow downwards to dependent lung regions, and the effect may be striking with higher levels of PEEP. During one-lung anesthesia, there is shunt blood flow both in the non-ventilated and the ventilated lung, and shunt can be much larger in the ventilated lung than thought of. Recruitment manoeuvres shall be directed to the ventilated lung and other physical and pharmacological measures can be taken to manipulate blood flow in one lung anesthesia.
Topics: Anesthesia; Blood Pressure; Hemodynamics; Humans; Pulmonary Circulation; Respiration, Artificial
PubMed: 15886595
DOI: No ID Found -
Exercise stress echocardiography of the pulmonary circulation: limits of normal and sex differences.Chest Nov 2012Exercise stress echocardiography has not been recommended in the diagnostic workup of pulmonary hypertension because of insufficient certainty about feasibility and...
BACKGROUND
Exercise stress echocardiography has not been recommended in the diagnostic workup of pulmonary hypertension because of insufficient certainty about feasibility and limits of normal.
METHODS
Doppler echocardiography pulmonary hemodynamic measurements were performed at a progressively increased workload in 56 healthy male and 57 healthy female volunteers aged 19 to 63 years. Mean pulmonary artery pressure (mPAP) was estimated from the maximal tricuspid regurgitation jet velocity. Cardiac index was calculated from the left ventricular outflow velocity-time integral. Pulmonary vascular distensibility a index, the percentage change of vessel diameter permm Hg of mPAP, was calculated from multipoint mPAP-cardiac output (CO) plots.
RESULTS
Peak exercise at 175 ±50 W was associated with an mPAP of 33±7 mm Hg and a CO of 18 ±5 L/min. The slope of mPAP-CO relationships was 1.5 ± 0.5 mm Hg/L/min, and the distensibility coefficient ( α ) was 1.3%± 1.0%/mm Hg. Maximal workload and cardiac index were higher in men than in women ( P , .05), but mPAP-cardiac index relationships were not different. However,women had a higher a (1.6%± 1.3%/mm Hg vs 1.1%± 0.6%/mm Hg, P < .05). The average mPAP-cardiac index slope was higher and a lower in subjects ≥50 years old. Upper limits of normal of mPAP at exercise were 34 mm Hg at a CO , 10 L/min, 45 mm Hg at a CO <20 L/min, and 52 mm Hg at a CO<30 L/min. These values are in keeping with previously reported invasive measurements.
CONCLUSIONS
Exercise stress echocardiography of the pulmonary circulation is feasible and allows for fl ow-corrected definition of upper limits of normal. Women have a more distensible pulmonary circulation.
Topics: Adult; Echocardiography, Stress; Female; Hemodynamics; Humans; Male; Middle Aged; Pulmonary Circulation; Reference Values; Sex Factors
PubMed: 22539647
DOI: 10.1378/chest.12-0071 -
Diseases of the Chest Nov 1969
Topics: Cardiology; History, 16th Century; History, 17th Century; History, 18th Century; History, 19th Century; History, 20th Century; History, Ancient; History, Medieval; Medicine, Arabic; Pulmonary Circulation
PubMed: 4899783
DOI: 10.1378/chest.56.5.409 -
Science (New York, N.Y.) Jun 1957
Topics: Blood Circulation; Pulmonary Circulation
PubMed: 13432788
DOI: 10.1126/science.125.3260.1231 -
Journal of Breath Research Sep 2012The results of experiments are described in which a known quantity of sterile deuterated water is injected directly into the pulmonary circulation via the right internal...
The results of experiments are described in which a known quantity of sterile deuterated water is injected directly into the pulmonary circulation via the right internal jugular vein of several haemodialysis patients and the deuterium to hydrogen ratio, D/H, in the exhaled lung water was measured using the flowing afterglow mass spectrometry technique. The breath D/H abundance was measured in sequential breath exhalations before and after the injection, providing data that are sufficiently detailed to follow the production and loss rate of D/H in the exhaled breath. Thus, in principle, considering isotope dilution the volume of water in the lungs and pulmonary circulation can be derived. However, it is seen that the maximum abundance that the breath D/H reached was much lower than anticipated by considering the likely volume of blood/water in the pulmonary circulation and so it is deduced that either 'leakage' of the injected deuterated water rapidly occurs from the pulmonary to the systemic circulation and/or isotope exchange of deuterium with hydrogen along the bronchial tree efficiently occurs, thus reducing the D/H in the exhaled breath. This latter phenomenon has important implications to breath analysis in which it is often assumed that so-called alveolar breath concentrations of metabolites reflect blood/systemic levels. Detailed consideration of the breath D/H abundances when the deuterium is equilibrated amongst the total body water, TBW, of the patients, which occurs about 40 min after injection of the deuterated water, allows the TBW of the patients to be estimated.
Topics: Breath Tests; Deuterium Oxide; Exhalation; Humans; Injections; Mass Spectrometry; Pulmonary Circulation; Renal Dialysis
PubMed: 22824740
DOI: 10.1088/1752-7155/6/3/036005 -
Clinical Pharmacology and Therapeutics 1966
Review
Topics: Humans; Pulmonary Circulation; Vasoconstrictor Agents; Vasodilator Agents
PubMed: 5331305
DOI: 10.1002/cpt196676807 -
Thoracic Surgery Clinics Nov 2007The vascular anatomy of the lungs is well known, although quite variable. Given the fragility of the vessels and the flow through them, it is imperative that the... (Review)
Review
The vascular anatomy of the lungs is well known, although quite variable. Given the fragility of the vessels and the flow through them, it is imperative that the thoracic surgeon to be intimately familiar with the normal patterns and anticipate unusual variants.
Topics: Humans; Lung; Pulmonary Artery; Pulmonary Circulation; Pulmonary Veins
PubMed: 18271172
DOI: 10.1016/j.thorsurg.2006.12.012