Evaluation of slope method for measuring pulmonary blood volume in man

1962 ◽  
Vol 17 (3) ◽  
pp. 497-502 ◽  
Author(s):  
Lockhart B. McGuire ◽  
Donald S. Dock ◽  
John W. Hyland ◽  
Donald C. Harrison ◽  
Florence W. Haynes ◽  
...  

Knowledge of the pulmonary blood volume is important in several areas of circulatory physiology. However, adequate methods for measuring this volume have not been established. The slope of an indicator-dilution curve across the central circulation has been used in several studies as an indication of this volume. In the present study the blood volume between pulmonary artery and left atrium was measured in 31 human subjects by an application of the well-established mean transit time principle. Slope volumes were also measured. There was poor agreement between the results of the two techniques. Unilateral pulmonary artery occlusion consistently reduced pulmonary blood volume by the mean transit time method, with only minor and less consistent changes in slope volumes. A close correlation between the slopes of curves from simultaneous pulmonary artery and left atrial injections suggested a predominant effect on both curves of factors at or distal to the left side of the heart. It was concluded that the slope method did not measure the pulmonary blood volume in man. Submitted on June 8, 1961

1962 ◽  
Vol 202 (5) ◽  
pp. 957-960 ◽  
Author(s):  
Charles J. McGaff ◽  
William R. Milnor

Changes in pulmonary blood volume produced by continuous intravenous infusion of serotonin (5-hydroxytryptamine) were measured in 16 experiments on ten dogs. Pulmonary mean transit time was measured by the dye dilution method, using consecutive injections into pulmonary artery and left atrium; pulmonary blood volume was calculated by multiplying this mean transit time by the cardiac output. Serotonin lowered pulmonary blood volume by an average of 2.9 ml/kg, or 26% of the control value ( P <0.001). Pulmonary vascular resistance increased 94 ru (resistance units) kg, and systemic vascular resistance fell 294 ru kg, effects similar to those reported by other investigators. The magnitude of the decrease in pulmonary blood volume indicates that a relatively large part of the pulmonary vascular bed is constricted by serotonin, and provides an example of shifting of blood from pulmonic to systemic circuits by reciprocal changes in the distensibility of these beds.


1961 ◽  
Vol 9 (1) ◽  
pp. 44-47 ◽  
Author(s):  
PEDRO ARAMENDÍA ◽  
JOSÉ D. FERMOSO ◽  
ALBERTO C. TAQUINI

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
L Houard ◽  
H Langet ◽  
S Militaru ◽  
M F Rousseau ◽  
A C Pouleur ◽  
...  

Abstract Background Assessment of congestion and cardiac function has been shown to have both therapeutic and prognostic implication for the management of patient with CHF. Pulmonary transit time (PTT) assessed by cMR is a novel parameter, which reflects not only hemodynamic congestion but also LV and RV function. Purpose We sought to explore the prognostic value of the pulmonary transit time assessed in seconds (PTT) and in beats (PTB) and the pulmonary blood volume indexed (PBVi) above conventional well-known risk factors including cMR-RVEF and estimated pulmonary artery pressure (eSPAP) in predicting outcomes. PBVi is defined by the product of PTB and the stroke volume indexed to body surface area. Methods 401 patients in sinus rhythm with a LVEF <35% (age 61±13 years; 25% female) underwent a cMR and an echocardiography. Patients were followed for a primary endpoint of overall mortality. Results Average cMR-LVEF was 23±7%, cMR-RVEF was 43±15%, average estimated systolic pulmonary pressure (eSPAP) was 33±12mmH, average PTT was 11±6s, PTB 8.9±5.6 bpm and average PBVi 305.5±254.9ml/m2. After a median follow-up of 6 years, 182 reached the primary endpoint. In univariate cox regression, age, ischemic cardiomyopathy, hypertension, diabetes, NYHA class III-IV, eSPAP >40mmHg, E/A ratio, e/e'ratio, cMR-RVEF, LV scar, PTT, PTB, PBVi, GFR, beta blockers and diuretics were associated with overall mortality. For the multivariate analysis, a baseline model was created where age, ischemic etiology, NYHA functional class III-IV, eSPAP >40 mmHg, beta-blockers and cMR-RVEF were found to be significantly and independently associated with the primary endpoint. PTT (X2 to improve = 5.3, HR: 1.03; 95% CI: [1.01; 1.06]; P=0.015), PTB (X2 to improve = 11.8, HR: 1.06; 95% CI: [1.03; 1.09]; P<0.001) and PBVi (X2 to improve = 7.7, HR: 1.08; 95% CI: [1.03; 1.14]; P=0.002) showed a significantly additional prognostic value over the baseline model (p<0.001). Conclusion Pulmonary transit time and pulmonary blood volume provide higher prognostic information over well-known risk factors including cMR-RVEF and eSPAP with high power to stratify prognosis in HF-rEF and might be promising tools to identify patients at higher risk among HF patients. Acknowledgement/Funding Fond National de recherche scientifique (FNRS)


2002 ◽  
Vol 95 (4) ◽  
pp. 835-843 ◽  
Author(s):  
Giorgio Della Rocca ◽  
Gabriella M. Costa ◽  
Cecilia Coccia ◽  
Livia Pompei ◽  
Pierangelo Di Marco ◽  
...  

Stroke ◽  
1974 ◽  
Vol 5 (5) ◽  
pp. 630-639 ◽  
Author(s):  
ROBERT L. GRUBB ◽  
MARCUS E. RAICHLE ◽  
JOHN O. EICHLING ◽  
MICHEL M. TER-POGOSSIAN

1959 ◽  
Vol 196 (3) ◽  
pp. 499-501 ◽  
Author(s):  
Robert C. Schlant ◽  
Paul Novack ◽  
William L. Kraus ◽  
Charles B. Moore ◽  
Florence W. Haynes ◽  
...  

Central blood volume (cardiac output times mean transit time) from right atrium to ascending aorta was determined by the indicator-dilution method in 22 open-chested dogs which had previously had their red blood cells tagged with Cr51. The actual amount of blood in the heart and lungs was calculated from the total radioactivity in the blended homogenate of these organs. The two measurements of central blood volume correlated well ( r = +.88), the indicator-dilution volumes averaging 12% greater. The discrepancy between measurements is probably related to the pulmonary circuit having a lower hematocrit than the large vessels. The results substantiate the use of the Stewart-Hamilton formula (cardiac output times mean transit time) to measure central blood volume.


1992 ◽  
Vol 262 (6) ◽  
pp. H1908-H1914 ◽  
Author(s):  
M. Ferrari ◽  
D. A. Wilson ◽  
D. F. Hanley ◽  
R. J. Traystman

This study tested the hypothesis that cerebral blood flow (CBF) is maintained by vasodilation, which manifests itself as a progressive increase in mean transit time (MTT) and cerebral blood volume (CBV) when cerebral perfusion pressure is reduced. Cerebral perfusion pressure was decreased in 10 pentobarbital-anesthetized dogs by controlled hemorrhage. Microsphere-determined CBF was autoregulated in all tested cerebral regions over the 40- to 130-mmHg cerebral perfusion pressure range but decreased by 50% at approximately 30 mmHg. MTT and CBV progressively and proportionately increased in the right parietal cerebral cortex over the 40- to 130-mmHg cerebral perfusion pressure range. Total hemoglobin content (Hb1), measured in the same area by an optical method, increased in parallel with the increases in CBV computed as the (CBF.MTT) product. At 30 mmHg cerebral perfusion pressure, CBV and Hb were still increased and MTT was disproportionately lengthened (690% of control). We conclude that within the autoregulatory range, CBF constancy is maintained by both increased CBV and MTT. Outside the autoregulatory range, substantial prolongation of the MTT occurs. When CBV is maximal, further reductions in cerebral perfusion pressure produce disproportionate increases in MTT that signal the loss of cerebral vascular dilatory hemodynamic reserve.


Neurosurgery ◽  
2006 ◽  
Vol 58 (4) ◽  
pp. 640-646 ◽  
Author(s):  
Iain D. Wilkinson ◽  
David A. Jellineck ◽  
David Levy ◽  
Frederik L. Giesel ◽  
Charles A. J. Romanowski ◽  
...  

Abstract OBJECTIVE: Glucocorticoid analogues are often administered to patients with intracranial space-occupying lesions. Clinical response can be dramatic, but the neurophysiological response is not well documented. This study sought to investigate the blood-lesion barrier, blood-brain barrier, and cerebral perfusion characteristics of patients who have undergone such therapy using magnetic resonance imaging. METHODS: Seventeen patients with intracranial mass-enhancing lesions underwent magnetic resonance imaging before and after 3 days of high-dose dexamethasone therapy. Assessments of blood-lesion barrier and blood-brain barrier integrity were based on a dynamic T1-weighted exogenous contrast technique that yielded the normalized maximal change in contrast uptake (T1-uptake). Perfusion was assessed using a dynamic T2*-weighted exogenous contrast technique to yield relative regional cerebral blood volume and first-moment mean transit time. Comparisons were made in T1-uptake, regional cerebral blood volume, and first-moment mean transit time of both enhancing lesion and contralateral normal-appearing white matter (CNAWM) obtained before and after dexamethasone. RESULTS: Significant reduction in T1-uptake was observed (19% decrease, P &lt; 0.005) within enhancing pathological tissue, whereas no significant alteration was detected in CNAWM. Regional cerebral blood volume was significantly reduced in both enhancing tissue (28% decrease, P &lt; 0.005) and in CNAWM (20% decrease, P &lt; 0.001). Bolus first-moment mean transit time significantly increased (2.0 s prolongation, P &lt; 0.05) in CNAWM, whereas there was no significant change (1.4 s prolongation, P &gt; 0.05) within enhancing tissue. CONCLUSION: Glucocorticoid-analogue therapy not only affects the permeability of the blood-lesion barrier and lesion blood volume but also affects blood flow within normal-appearing contralateral parenchyma. There is a need for controls in steroid therapy in magnetic resonance imaging studies, which involve assessments of cerebrovascular function.


2013 ◽  
Vol 185 (1) ◽  
pp. 310-318
Author(s):  
Charles Her ◽  
Yong Han Kim ◽  
Sang Yoon Jeon

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