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F Brunet

Publications and source records attributed to F Brunet.

At least 37 records · Page 2Linked to original sources
PubMed1994

The mariner transposable element in the Drosophilidae family.

The distribution of the mariner transposable element among Drosophilidae species was investigated using three different techniques, i.e. squash blots, Southern blots and PCR amplification, using two sets of primers (one corresponding to the Inverted Terminal Repeats and the other to two conserved regions of the putative transposase). Our results and those of others show that the distribution of mariner is not uniform and does not follow the phylogeny of the host species. An analysis of geographical distribution, based on endemic species, shows that mariner is mainly present in Asia and Africa. At least two hypotheses may be proposed to explain the specific and geographical distributions of this element. Firstly, they may be the results of several horizontal transmissions between Drosophila species and/or between Drosophila species and one or several donor species outside the Drosophilidae family. Secondly, these particular distributions may correspond to the evolution of the mariner element from an ancestral copy which was present in the ancestor of the Drosophilidae family.

Animals↗
PubMed1994

Permissive hypercapnia and intravascular oxygenator in the treatment of patients with ARDS.

This open clinical study was aimed at testing the hypothesis that an intravascular oxygenator (IVOX) may help to perform permissive hypoventilation in 10 patients with severe ARDS. After initial evaluation, we tried to reduce ventilator settings before and after IVOX implantation. Before IVOX, poor clinical tolerance and worsening oxygenation did not allow for a significant decrease in ventilator settings. With IVOX, peak inspiratory pressure (PIP) was reduced from 47 to 39 cm H2O (p = 0.005) and minute ventilation from 13 +/- 3.5 to 11 +/- 3 L/min. CO2 removal by IVOX allowed a significant decrease in PaCO2 from 66 +/- 15 to 59 +/- 13 mm Hg. Improvement of oxygenation with IVOX was not significant. Furthermore, interruption of oxygen flow through IVOX did not change oxygenation variables. Tolerance of the IVOX device was good, but insertion of the device was followed by a significant decrease in both cardiac index and pulmonary wedge pressure. In conclusion, IVOX improves tolerance of hypoventilation by limiting hypercapnia in ARDS patients. These preliminary results must be confirmed by a randomized controlled study.

Adult↗
PubMed1994

Extracorporeal carbon dioxide removal technique improves oxygenation without causing overinflation.

Extracorporeal CO2 removal combined with low frequency positive pressure ventilation (ECCO2R-LFPPV) improves gas exchange and decreases peak pressures, respiratory rates, and tidal volumes in animals and in humans. Recent evidence suggests that pulmonary barotrauma results from lung overinflation rather than from high pressures. This study was to test the hypothesis whether ECCO2R-LFPPV could improve gas exchange without causing lung overinflation, despite the use of higher levels of PEEP, when compared with conventional mechanical ventilation. Eleven patients with severe adult respiratory distress syndrome (ARDS) who failed to respond to different modes of mechanical ventilation were treated with ECCO2R-LFPPV. Risk of pulmonary barotrauma was evaluated by static pressure-volume (P-V) curves and dynamic changes in volumes monitored by respiratory inductive plethysmography (Respitrace). ECCO2R-LFPPV PaO2/FIO2 increased from 79 +/- 21 to 207 +/- 108 (p = 0.003). Risk of barotrauma, as shown by the shape of the P-V curve, was present in all patients receiving mechanical ventilation even though most of them were treated with permissive hypoventilation. By contrast, no evidence of persistent lung overinflation could be detected by either static P-V curves or dynamic measurements in nine of 11 patients who were treated by ECCO2R-LFPPV. The two remaining patients had severe airway obstruction because of bleeding, and they remained ventilated with persistent risk of barotrauma. We conclude that ECCO2R-LFPPV improves gas exchange without causing lung overinflation in a majority of patients with ARDS.

Adolescent↗
PubMed1994

Enoximone vs nicardipine during the early postoperative course of patients undergoing cardiac surgery. A prospective study of two therapeutic strategies.

The hemodynamic effects of enoximone and nicardipine were compared during the early postcardiac surgery period in 40 patients with systemic hypertension and moderate cardiac dysfunction. Patients were prospectively randomized into two groups. Mean right atrial pressure was maintained above 7 mm Hg. The drug infusion rate was adjusted to maintain mean systemic artery pressure (SAP) within the 65 to 80 mm Hg range. Complete hemodynamic evaluations were performed before any drug infusion and during the following 24 h with special attention to O2-related variables. Oxygen consumption, cardiac index, and stroke index improved significantly and similarly in the two groups. The SAP and systemic vascular resistance decreased more rapidly in the enoximone group but whole body lactate level increased after the second hour of infusion. Furthermore, this was paralleled by an arteriovenous O2 contents difference deficit. In our study, nicardipine was found superior over enoximone in terms of recovery from intraoperative tissue hypoxia. Furthermore, enoximone's inotropic effects were not found to be clinically relevant.

Cardiac Surgical Procedures↗
PubMed1993

Extracorporeal carbon dioxide removal and low-frequency positive-pressure ventilation. Improvement in arterial oxygenation with reduction of risk of pulmonary barotrauma in patients with adult respiratory distress syndrome.

Mortality of the adult respiratory distress syndrome (ARDS) remains high and could be increased by pulmonary barotrauma induced by positive-pressure mechanical ventilation. Extracorporeal CO2 removal combined with low-frequency positive-pressure ventilation (ECCO2R-LFPPV) has been proposed to reduce lung injury while supporting respiratory failure. Use of this technique in 23 patients resulted in the following: a dramatic and highly significant increase of PaO2 obtained rapidly with ECCO2R-LFPPV, allowing subsequent reduction in inspired oxygen fraction; a reduction of the risk of barotrauma evidenced by a significant decrease in pressures and insufflated volumes; a survival rate of 50 percent. Bleeding was the only complication related to the technique and was the cause of death in four patients. This method allowed improvement in gas exchange along with reduction of the risk of barotrauma caused by the ventilator.

Adolescent↗
PubMed1993

Recovery from staphylococcal septicaemia in neutropenic patients without removal of the previously inserted central venous catheter.

OBJECTIVES: An open clinical study was conducted in the haematological department of an intensive care unit to investigate cure of staphylococcal septicaemia in neutropenic central venous catheter carriers without removal of the line. METHODS: Thirteen neutropenic patients with a central venous catheter were investigated. These patients were under treatment for haematological malignancies and had at least 2 blood cultures positive for Staphylococcus aureus or coagulase-negative staphylococcus. Antibiotherapy including vancomycin was given through the catheter. Each case was re-evaluated on day 3 of treatment. The catheter was removed if blood cultures remained positive or if clinical signs of bloodstream infection persisted or worsened. RESULTS: Clinical recovery was obtained in ten patients and bacterial eradication in twelve. Three patients died from septic shock: two deaths were not related to staphylococcal septicaemia; one death was due to a staphylococcal septic shock which occurred within a few hours of admission, despite of prompt removal of the central venous catheter. CONCLUSIONS: With appropriate antibiotherapy, leaving the central venous catheter in place would appear possible in cases of staphylococcal septicaemia. Response to treatment, however, must be carefully monitored.

Adult↗
PubMed1993

Modelling of passive expiration in patients with adult respiratory distress syndrome.

The time-course of volume change during passive expiration preceded by an end-inspiratory hold was studied with a biexponential model in six adult respiratory distress syndrome (ARDS) patients. We measured the initial volumes and time constants of the fast (tau 1), and the slow (tau 2) compartments of expiration, as well as the static elastance of the respiratory system. The results were compared to those of 11 normal subjects. We observed that: 1) the biexponential model fitted closely the volume decay; 2) the fast compartment was responsible for 81 +/- 7% (ARDS) versus 84 +/- 10% (controls) of the total volume exhaled, with tau 1 = 0.35 +/- 0.11 s (ARDS) versus 0.50 +/- 0.22 s (controls); 3) the slow compartment contributed only 19 +/- 6% (ARDS) versus 16 +/- 7% (controls), with tau 2 = 4.67 +/- 2.38 s (ARDS) versus 3.27 +/- 1.54 s (controls); and 4) static elastance was higher in ARDS patients. The findings could be explained in terms of a four parameter viscoelastic model of the respiratory system.

Adolescent↗
PubMed1992

Effects of aprotinin on hemorrhagic complications in ARDS patients during prolonged extracorporeal CO2 removal.

The effects of aprotinin, a broad-based proteinase inhibitor, in the management of hemorrhagic complications during prolonged venovenous extracorporeal CO2 removal in patients with adult respiratory distress syndrome are not evaluated. In two patients, aprotinin infusion was added to heparin to treat bleeding, occurring after few days of bypass and responsible for respiratory and hemodynamic deterioration. After aprotinin infusion (loading dose of 2 x 10(6) kIU followed by a continuous infusion of 5 x 10(5) kIU/h) combined with heparin, bleeding vanished until the end of bypass.

Adult↗
PubMed1992

Outcome of patients with systemic rheumatic disease admitted to medical intensive care units.

The outcome of patients admitted to intensive care units is known to be influenced by such factors as age, previous health status, severity of disease, and diagnosis. To estimate the outcome of such patients with systemic rheumatic diseases and to determine if the severity of these diseases unfavourably influences the prognosis at the time of admission to a medical intensive care unit, the clinical courses of all patients with systemic rheumatic disease admitted to two medical intensive care units between January 1978 and December 1988 were studied retrospectively. Sixty nine patients with systemic lupus erythematosus (n = 16), necrotising vasculitis (n = 19), rheumatoid arthritis (n = 19), and other systemic rheumatic diseases (n = 15) were included. The mean (SD) age on admission into the medical intensive care unit was 53 (17) years and the mean simplified acute physiological score was 12 (5.5). The principal diagnoses on admission were infectious complications (29/69 patients) and acute exacerbation of the systemic rheumatic disease (19/69 patients). The death rate in the medical intensive care unit was 33% (23/69 patients) and was similar to that of a non-selected population with comparable simplified acute physiological score. The death rate in hospital was 42% (29/69 patients). Infection was the main cause of death in the medical intensive care unit (19/23 patients) and the infection was mainly acquired in the unit. Only the simplified acute physiological score on admission was a statistically significant prognostic factor: the simplified acute physiological score in patients who died was 15 (5.2) v 9.9 (4.7) for survivors. Long term outcome analysis showed that 83% (33/40 patients) of patients were still alive after admission to the medical intensive care unit with a follow up time between two months and nine years (mean 38 months). The death rate was relatively high and was mainly due to nosocomial infections. It was not different, however, from that of nonselected patients and the long term prognosis was highly favourable. This shows that the complications are often reversible, particularly infectious applications, and justifies admission to the medical intensive care unit of this group of patients.

Adult↗
PubMed1992

Passive partitioning of respiratory volumes and time constants in ventilated patients.

If the thoracoabdominal partitioning of volumes in the mechanical respiratory apparatus was constant, one transducer of indirect spirometry should be sufficient to measure volume variations. To verify this hypothesis we used respiratory inductive plethysmography (RIP) in 16 paralysed patients, of whom eight had normal lungs and 8 had not, to measure: 1) the thoracoabdominal partitioning of volumes (400-1,200 ml) insufflated from either a syringe (Syr) or a ventilator (Vent); and 2) thoracic (Tho) and abdominal (Abd) time constants (T0.368) on spontaneous deflation to barometric pressure. In eleven additional subjects with normal lungs we measured only the time constants. 1) Correlation coefficients of the calibration lines were in all but one subject > 0.98. In all patients the error of volume was < +/- 10% when either one of two coils alone was used to assess volumes with no difference between the two coils; 2) Partitioning varied little with volumes (4 +/- 2%), but widely between subjects, with no group average significant difference between Syr and Vent; 3) T0.368 were identical for Tho and Abd except in one patient; 4) Partitioning and T0.368 were volume size independent. We conclude that, to measure volume variations and time constants in ventilated, paralysed patients, the use of either a thoracic or abdominal single coil RIP is justified. We also provide the normal range for time constant in 19 subjects (0.73 +/- 0.29 s).

Adult↗
PubMed1991

Hemodialysis for acute renal failure in patients with hematologic malignancies.

OBJECTIVE: To assess the prognosis of patients with hematologic malignancies in acute renal failure who require hemodialysis. DESIGN: Retrospective study. SETTING: ICU. PATIENTS: Forty-three consecutive patients. METHODS: Prognostic analysis using both univariate and multivariate (stepwise regression) methods. RESULTS: Fifteen (35%) patients recovered from acute renal failure and 12 (28%) were discharged from the ICU. The prognosis of patients with acute renal failure linked to sepsis is poorer than the prognosis of the patients with acute renal failure from other etiologies. Only one patient survived in the former group (n = 26) and 11 in the latter group (n = 17); p less than .0001 in multivariate analysis. When accompanied by associated respiratory failure, mortality rate was higher (93% vs. 33%; p less than .0001). The Simplified Acute Physiology Score (SAPS) calculated within the first 24 hr of admission was significantly (p less than .001) related to mortality when the SAPS was greater than or equal to 13. The presence of neutropenia and the type of hematologic malignancy were not related to a worse prognosis. Tolerance to hemodialysis appeared good, and complications were rare.

Acute Kidney Injury↗
PubMed1991

A single-compartment model cannot describe passive expiration in intubated, paralysed humans.

The time-course of thoracic volume changes (respiratory inductive plethysmograph) during relaxed expiration was studied in 11 intubated, paralysed, mechanically ventilated subjects. The semilog volume-time curves show that expiration is governed by two apparently separate mechanisms: one causes emptying of most of the expired volume (approximately 80%) with a time constant of 0.50 +/- 0.22 s for a baseline tidal volume of 0.44 +/- 0.12 l (mean +/- SD) and 0.37 +/- 0.14 s when the tidal volume is reduced (VTP); the other contributes a relatively small amount to the expired volume over a significantly longer time, the time constant amounting to 3.27 +/- 1.54 s for baseline VT and 2.95 +/- 1.65 s for VTp. The first mechanism probably reflects the standard elastic and flow resistive properties of the respiratory system, while the second, slower compartment, is probably an expression of the viscoelastic properties of the pulmonary and chest wall tissues.

Adult↗
PubMed1990

Role of tricuspid regurgitation and left ventricular damage in the treatment of right ventricular infarction-induced low cardiac output syndrome.

To evaluate, in right ventricular (RV) myocardial infarction, the role of tricuspid regurgitation (TR) and left ventricular (LV) damage and the response to treatment of low cardiac output, 20 patients were prospectively studied. Volume infusion increased cardiac output only slightly (11%, p less than 0.001), despite a dramatic increase in ventricular filling pressures. Dobutamine (4 micrograms.kg-1.min-1) markedly increased cardiac output (24%, p less than 0.001) with a decrease in ventricular filling pressures. In the 5 patients with TR, dobutamine only modestly increased cardiac output (9 vs 26%, p less than 0.001), while stroke index and LV end-diastolic dimensions decreased in comparison (-5 vs 33% and -6 vs 9%, respectively, p less than 0.001). In the absence of TR (n = 15), there was no significant difference in response to volume expansion between patients with normal (n = 7) and depressed LV ejection fraction (n = 8). In contrast, dobutamine, in patients with depressed LV function, induced a greater increase in cardiac output (38 vs 17%, p less than 0.01) and RV ejection fraction (36 vs 12%, p less than 0.05). All patients with RV infarction-induced low cardiac output responded only modestly to volume loading. Dobutamine is particularly efficacious in patients without TR who have depressed LV function by improving RV function and, consequently, LV preload. In the 5 patients with TR, increasing RV contractility failed to improve the forward stroke volume by increasing the regurgitant fraction.

Adult↗
PubMed1990

Is intensive care justified for patients with haematological malignancies?

The course of 260 adults with haematological malignancies admitted to a medical intensive care unit was studied to evaluate the value of life support techniques and to research predictive factors. The overall in the medical intensive care unit (MICU) and hospital mortality rates were respectively 43% (113 patients) and 57% (148 patients). Among survivors, 64% (49 patients) were still alive after 6 months and 44% (35 patients) after 1 year. Among 34 haemodialysed patients, the MICU mortality was 67% (23 patients) and among 111 mechanically ventilated patients 85% (94 patients). Prolonged mechanical ventilation, more than seven days, was performed in 11 of the 17 survivors and did not influence long term survival. No individual predictor of mortality was found comparing survivors and non-survivors. However, SAPS, intractable sepsis and failure of more than one organ system were significantly different in non-survivors (p less than 0.001). Among the 20 patients requiring both mechanical ventilation and haemodialysis, only two left the MICU and both died soon thereafter. We conclude that life support therapy should be initiated in patients with haematological disorders and that prolonged mechanical ventilation is compatible with long term survival. However, the combination of mechanical ventilation and haemodialysis is always associated with a poor prognosis and therefore the use of both techniques simultaneously for one patient is questionable.

Adult↗