Search PubMed⌕ Search

Biomedical subjects

F Jardin

Publications and source records attributed to F Jardin.

At least 91 records · Page 5Linked to original sources
PubMed1985

Right ventricular volumes by thermodilution in the adult respiratory distress syndrome. A comparative study using two-dimensional echocardiography as a reference method.

Measurements of right ventricular ejection fraction and volumes were obtained at bedside by the thermodilution method performed with a fast-response balloon-tipped thermistor in a group of 18 patients undergoing respiratory therapy for the adult respiratory distress syndrome (ARDS). These measurements were compared with right ventricular dimensions simultaneously obtained with two-dimensional echocardiography. A significant correlation was found between right ventricular ejection fraction by thermodilution and two-dimensional echocardiographic fractional area contraction (r = 0.74; p less than 0.001), between right ventricular end-diastolic volume by thermodilution and two-dimensional echocardiographic end-diastolic area (r = 0.70; p less than 0.001), and between right ventricular end-systolic volume by thermodilution and two-dimensional echocardiographic end-systolic area (r = 0.78; p less than 0.001). Right ventricular end-diastolic pressure, a commonly used index of right ventricular preload, did not correlate with two-dimensional echocardiographic end-diastolic area. In conclusion, the thermodilution method allowed reliable measurements of right ventricular ejection fraction and volumes at bedside in critically ill patients. Appraisal of right ventricular end-diastolic volume by this method appeared to be a better predictor of right ventricular preload than were the measurements of pressure.

Adolescent↗
PubMed1985

Influence of lung and chest wall compliances on transmission of airway pressure to the pleural space in critically ill patients.

Nineteen patients with acute respiratory failure were divided into three groups according to their total compliance (CT). Transmission of airway pressure to the pleural space was then evaluated by measurement of esophageal pressure at both end-expiration and end-inspiration, and at three levels of PEEP. Chest wall (CW) and lung complicance (CL) were also calculated from simultaneous measurements of lung volume changes induced by tidal delivery. In group 1 (CT greater than 45 ml/cmH2O), 37 percent of airway pressure was transmitted to pleural space. In group 2 (CT between 45 and 30 ml/cmH2O), 32 percent of airway pressure was transmitted to the pleural space. In group 3 (CT less than 30 ml/cmH2O), only 24 percent of airway pressure was transmitted to the pleural space. These differences are statistically significant (p less than 0.001) and illustrate the influence of a progressive increase in lung stiffness (CL = 100.3 +/- 17.2 ml/cmH2O in group 1, CL = 45.0 +/- 6.3 ml/cmH2O in group 2, and CL = 28.6 +/- 8.9 ml/cmH2O in group 3) on transmission of airway pressure to the pleural space. Despite lesser transmission of airway pressure to the pleural space in the most damaged lungs, no significant difference was found between groups with regard to transmural venous pressure changes throughout the study.

Acute Disease↗
PubMed1984

[Acute right ventricular failure. Treatment with dobutamine].

Acute right ventricular failure is commonly observed during respiratory intensive care, particularly in patients suffering from massive pulmonary embolism, chronic obstructive pulmonary disease or adult respiratory distress syndrome. The haemodynamic effects of a continuous dobutamine infusion at the rate of 9.4 +/- 3.7 micrograms/kg/min were assessed in a group of 15 patients with acute and isolated right ventricular failure, as evidenced by haemodynamic and two dimensional echocardiographic measurements. This inotropic agent induced at 37% increase in mean cardiac index and a 25% increase in mean stroke index, with only a 10% increase in mean heart rate. Moreover, measurement of the right ventricular ejection fraction by a thermal dilution technique performed in 10 patients demonstrated that dobutamine consistently and significantly increased right ventricular systolic function and also significantly reduced right ventricular end-diastolic tension. In conclusion, it appeared that dobutamine was able to improve circulatory status in patients with acute right heart failure or various origins.

Acute Disease↗
PubMed1984

[Evaluation of the severity of pulmonary embolism. Value of the measurement of stable carbon monoxide transfer capacity].

A non-invasive and easily repeatable method of pulmonary gas exchange evaluation, using measurements of stable carbon monoxide transfer capacity (DLCO) and alveolar-capillary ductance ( DuaCo ), was compared to a complex, invasive method of pulmonary vascular bed evaluation (pulmonary angiography) in 17 patients during the first 24 hours of pulmonary embolism. DLCO and DuaCo measurements were subsequently repeated in several of the patients during the course of the disease. The study showed that DLCO was lowered in both massive (Walsh's angiographic index 12.9 +/- 1.9) and submassive (Walsh's index 4.1 +/- 1.3) pulmonary embolism, with values of 7.0 +/- 2.5 and 7.0 +/- 1.8 ml/min/mm Hg respectively. It also showed a highly significant correlation between the degree of vascular obstruction, as determined by Walsh's angiographic index, and the reduction of alveolar-capillary gas exchange, as evaluated by DuaCo (r = 0.80; p less than 0.001). A progressive improvement in the pulmonary capillary bed perfused could be suspected from the results of DuaCo monitoring during the course of embolism.

Carbon Monoxide↗
PubMed1984

Circulatory failure in acute pulmonary embolism.

Circulatory failure occurs in about 10% of patients with pulmonary embolism, resulting from a massive obstruction of the pulmonary arterial bed. Hemodynamic and respiratory features are well established; they involve precapillary pulmonary hypertension, low cardiac output state, elevated filling pressure for the right ventricle, and venous admixture. More recently, two-dimensional echocardiography permitted the visualization of pulmonary artery and right heart enlargement, reduced right ventricular ejection fraction, and tricuspid regurgitation. Evaluated by this latter means, left ventricular systolic function appeared unchanged, but diastolic function might be reduced by septal bulging.

Cardiac Output, Low↗
PubMed1984

Two-dimensional echocardiographic demonstration of acute myocardial depression in septic shock.

A 50-yr-old woman exhibiting streptococcal neck cellulitis developed severe septic shock with low cardiac output, which was reversed by infusion of dopamine plus dobutamine. Two-dimensional echocardiography performed at the bedside demonstrated severe myocardial failure. The patient's condition remained dependent on inotropic drug support for 2 days and ultimately improved. Two-dimensional echocardiography repeated on the fourth day corroborated the disappearance of transient myocardial failure.

Cardiac Output, Low↗
PubMed1984

Echocardiographic evaluation of ventricles during continuous positive airway pressure breathing.

Using M-mode and two-dimensional echocardiography, we have compared left and right ventricular dimensions at expiration and inspiration in a group of 12 healthy young volunteers during the following two distinct periods: 1) a control period with atmospheric pressure breathing, and 2) a continuous positive airway pressure (CPAP) period with 15 cmH2O end-expiratory pressure breathing. In 6 of the 12 subjects we also evaluated inferior vena caval size, using the same technique. Inspiratory decrease in left ventricular short-axis area (A), length (L), calculated volumes (V = 5/6 AL), and inspiratory increase in right ventricular short-axis diameter and long-axis area were evident at both control and CPAP periods. CPAP also produced a marked decrease in left and an increase in right ventricular dimensions during both expiration and inspiration and a significant decrease in calculated stroke output. An increase in vena caval size during CPAP breathing indirectly suggested a decrease in venous return, but the finding of an unchanged percent of inspiratory change of this vessel during CPAP indicated that the inspiratory augmentation of venous return was still present. On the other hand, the finding of an increased right ventricular size indicated that the right ventricle was afterloaded by CPAP; this probably could explain the observed reduction in calculated stroke output.

Adult↗
PubMed1984

Two-dimensional echocardiographic assessment of left ventricular function in chronic obstructive pulmonary disease.

In 10 patients undergoing therapy for a mild exacerbation of their chronic obstructive pulmonary disease (COPD), a quantitative two-dimensional echocardiographic (2DE) study was performed together with hemodynamics to assess left ventricular (LV) function. From the 2DE examination, which was made up of parasternal, subcostal, and apical views, measurements of LV short axis end-diastolic and end-systolic areas (A) at the high papillary muscle level and long axis end-diastolic and end-systolic length (L) permitted us to calculate LV end-systolic and end-diastolic volumes (V) using the formula V = 5/6 AL. Compared with the same measurements obtained in a group of 12 normal volunteers, patients with COPD exhibited a markedly reduced LV cavity (LVES, 28.9 +/- 14.6 ml/m2 versus 51.5 +/- 11.0 ml/m2; LVEDV, 67.7 +/- 24.6 ml/m2 versus 103.2 +/- 19.9 ml/m2). An increased thickness of both left ventricular free wall and interventricular septum was also evidenced in patients with COPD. Left ventricular systolic function, assessed using both peak systolic blood pressure/end-systolic volume ratio and calculated left ventricular ejection fraction, was found to be clearly enhanced in patients with COPD. The influence of right ventricular enlargement on left ventricular diastolic function was also investigated in patients with COPD using progressive volume loading and 2DE right ventricular measurements. After a given threshold of volume loading, reduction in stroke index, opposite variations in right and left ventricular size and septal flattening, suggested the occurrence of ventricular interaction.

Adult↗
PubMed1982

[Influence of positive end-expiratory pressure ventilation on left ventricular function (author's transl)].

During the last decade several attempts have been made to elucidate the mechanism of the fall in cardiac output observed during positive end-expiratory pressure ventilation (PEEP). some of these studies have given conflicting results, but the weight of experimental and clinical evidence available today points to a coherent physiopathology. PEEP does not alter left ventricular contractility, but it impedes left ventricular filling by reducing pulmonary venous return and left ventricular compliance. In patients under high PEEP, reduction in left ventricular distensibility results from septal shift and flattening of the left ventricle due to right ventricular overload.

Diastole↗
PubMed1982

[Shock during leptospirosis icterohaemorrhagica. Four cases (author's transl)].

Four patients with leptospirosis icterohaemorrhagica (LH) were admitted to an intensive care unit in a state of shock. Haemodynamic studies showed that the shock was due to three different mechanisms which were often associated or successive in the same patient: (1) septic shock with fall of systemic vascular resistance (SVR) and no widening of arteriovenous oxygen difference (AVDO2); (2) cardiogenic shock, probably due in part to specific myocarditis, with reduced left ventricular work and normal or high pulmonary wedge pressure; and (3) hypovolaemic shock with the increased SVR and widened AVDO2. These data suggest that haemodynamic studies are required in patients with LIH associated with shock in order to determine its mechanism and provide guidelines for its treatment.

Adult↗
PubMed1982

[Outcome of the adult acute respiratory distress syndrome. Predictive value of a severity index calculated from arterial oxygenation (author's transl)].

A retrospective study was carried out a group of 50 adult patients who had presented with acute respiratory distress syndrome and had all been treated by mechanically controlled ventilation with positive end-expiratory pressure (PEEP). The predictive value of the so-called "severity index" was tested. This index, which is used from the second day of treatment onward to predict with strong probability whether the lung lesions will subside or develop, is obtained from the PaO2 after corrections taking into account the FiO2 and the PEEP level. The study also supplied information on the outcome of lung lesions which may result in one of four possible courses of about equal frequency: the patient may either die or be cured rapidly after less than a week of assisted ventilation, or he may die at a later date or be cured slowly after more than a week of assisted ventilation.

Female↗
PubMed1982

Mechanism of paradoxic pulse in bronchial asthma.

To elucidate the mechanism of paradoxic pulse in severe bronchial asthma, we performed hemodynamic studies and measured esophageal pressure in nine patients who had status asthmaticus and clinical paradoxic pulse. Two-dimensional echocardiography allowed simultaneous assessment of cyclic changes in right- and left-heart size throughout the respiratory cycle. Esophageal pressure varied from a markedly negative level during inspiration (-24.4 +/- 6.5 cm H2O) to a positive level during expiration (7.6 +/- 6.0 cm H2O). Competition between right- and left-heart chambers for pericardial space during inspiration was suggested by the reduced left ventricular cross-sectional area at end-systole (-24%, p less than 0.01) and end-diastole (-32%, p less than 0.01), the leftward septal shift, and the increased right ventricular internal diameter at end-systole (42%, p less than 0.01) and end-diastole (40%, p less than 0.001). Competition for filling, however, could not entirely account for the paradoxic pulse, for systemic and pulmonary pulse pressures were almost (within one cardiac cycle) in phase: both were minimal at inspiration and maximal at expiration. The increase in impedance to right ventricular ejection is another major factor reducing left ventricular preload at inspiration. This reduction in preload was shown to be the predominant mechanism for the decrease in left ventricular stroke output at inspiration.

Adult↗
PubMed1982

Hemodialysis in septic patients: improvements in tolerance of fluid removal with concentrated albumin as the priming fluid.

Hemodynamic function and volume of ultrafiltration (UF) during hemodialysis were studied in 8 patients with anuric acute renal failure (ARF) and severe sepsis. Patients were alternatively dialyzed with a saline priming (every 2 days) and with a 17.5% albumin priming. Hypovolemia, as indirectly reflected by reduced left ventricular filling pressure, decreased cardiac output (CO), and decline in mean systemic arterial pressure (MAP), was observed during the hemodialysis procedure using saline as the first prime. Hemodialysis was tolerated better after concentrated albumin priming; left ventricular filling pressure increased during the 1st h of dialysis, whereas CO and MAP remained close to that of control values. Furthermore, UF could be increased progressively without major hemodynamic consequences in the patients who received a concentrated albumin priming; moreover, larger volumes of fluid were removed.

Acute Kidney Injury↗
PubMed1981

Influence of positive end-expiratory pressure on left ventricular performance.

Although left ventricular dysfunction is common during ventilatory support with positive end-expiratory pressure (PEEP), the mechanism of this disorder remains unclear. In 10 patients with the adult respiratory-distress syndrome we studied the effects of a stepwise increase in PEEP from 0.to 30 cm H2O on left ventricular output, intracardiac transmural pressures, and two-dimensional echocardiographic measurements of left ventricular cross-sectional area at end-systole and at end-diastole. Increasing PEEP was associated with progressive declines in cardiac output, mean blood pressure, and left ventricular dimensions and with equalization of right and left ventricular filling pressures. The radius of septal curvature decreased at both end-diastole and end-systole, implying a leftward shift of the interventricular septum. At the highest PEEP, blood-volume expansion did not restore cardiac output, although left ventricular transmural filling pressures had returned to base-line values. We conclude that decreased cardiac output during PEEP is mediated by a leftward displacement of the interventricular septum, which restricts left ventricular filling.

Blood Pressure↗
PubMed1981

Controlled ventilation with best positive end-expiratory pressure (PEEP) and high level PEEP in acute respiratory failure (ARF).

We assessed hemodynamics, total lung and chest wall compliance (CT) and gas exchange using two different levels of PEEP during controlled ventilation in two different groups of patients with ARF; in the first group (Group 1, 12 patients) chest X-Rays showed a symmetrical pattern of bilateral alveolar infiltrates; in the second group (Group 2, 5 patients) chest X-Ray showed a asymmetrical pattern with unilateral lobar consolidation. A first level of PEEP (best PEEP = 9 +/- 3 cm H2O) produced an improvement in CT and in gas exchange with a slight decrease in cardiac index in both groups; but improvement in PaO2 (from 64 +/-33 to 122 +/- 76 torr, p less than 0.001 in Group 1, and from 76 +/- 39 to 91 +/- 33 torr, p less than 0.05 in Group 2) and decrease in QS/QT were not as well marked in Group 2 as i Group 1. A second level of PEEP (high level PEEP: 20 +/- 4 cm H2O) produced a sharp decrease in CT and required hemodynamic support in each case (blood volume expansion with or without Dopamine infusion) to maintain cardiac index within a normal range. In Group 1 this high level PEEP produced a greater improvement in gas exchange (PaO2 increased from 122 +/- 76 to 194 +/- 76, p less than 0.01) but in Group 2 it had a deleterious effect, producing a decrease in PaO2 (from 91 +/- 33 to 76 +/- 41 torr, p less than 0.05), and an increase in QS/QT; with this higher PEEP we also noted an increase of alveolar dead space in Group 2. This study demonstrates the efficiency of high levels of PEEP to reduce QS/QT in ARF but also shows its limitations: namely reduction in cardiac performance and in efficiency if the damage to one lung is significantly more pronounced than that to the other lung.

Acute Disease↗
PubMed1981

Dobutamine: a hemodynamic evaluation in human septic shock.

The hemodynamic effect of dobutamine infusion (DI) was studied in 19 patients with septic shock. DI resulted in hemodynamic improvement as indicated by a significant increase in cardiac index (+36%, p less than 0.001), stroke index (+15%, p less than 0.01), mean arterial pressure (+20%, p less than 0.01), and a significant decrease in aVDO2 (-27%, p less than 0.01). This hemodynamic improvement occurred concomitantly with a fall in both right and left filling pressures. Mean systemic arterial resistance remained unchanged with a scatter of individual responses depending on other factors, such as infusion rate, initial vascular resistance, and underlying hemodynamic setting. In patients mechanically ventilated, venous admixture in the lung (Qs/Qt) during DI increased significantly (+30%, p less than 0.001) and insignificantly reduced PaO2, but this adverse effect was not observed when PEEP was used in patients mechanically ventilated. It is concluded that dobutamine can be useful in management of septic shock, particularly when filling pressures are high because of fluid overload or cardiac failure.

Adult↗