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S Arnaud

Publications and source records attributed to S Arnaud.

At least 37 records · Page 2Linked to original sources
PubMed2000

Efficacy of a new neuroprotective agent, gacyclidine, in a model of rat spinal cord injury.

Prevention of the immediate excitotoxic phase occurring in response to spinal cord injury (SCI) is a major issue to reduce the neuronal damage responsible for any ensuing motor deficits. The present study evaluated the neuroprotective efficacy of three noncompetitive NMDA receptor antagonists: Gacyclidine (GK-11), a new compound, Dizocilpine (MK-801), and Cerestat (CNS-1102) in a rat spinal cord contusion model. To mimic human SCI, a standardized model of rat spinal cord closed contusion in which animals spontaneously and progressively recover from the induced paraplegia was employed. Such model, characterized by a slow recovery of hindlimb locomotor function enables easy quantification of the neuroprotection at both the behavioral and cellular level. The animals were treated intravenously with the respective drugs 10 min after the spinal contusion. The dose range study suggested that 1 mg/kg of Gacyclidine was the most effective dose to promote functional recovery in reducing by half the time needed to reach full locomotor recovery. Racemate and enantiomers of Gacyclidine showed similar neuroprotective effects, but treatment with the enantiomers were not as efficacious in promoting full functional recovery. Similarly, a prolonged treatment with the racemate was not as efficious as a single dose, suggesting that a prolonged blockade of the amino-excitatory neurotransmission may be deleterious. Finally, Dizocilpine and Cerestat treatments induced only a partial and delayed neuroprotective effect compared to Gacyclidine. Neuroprotection characterized by a reduction of the cystic cavity and of the astrogliosis was observed with all treatments. As Gacyclidine is already in clinical trials, the present findings suggest the premise that it is a promising agent for limiting the initial neuronal damage induced by CNS trauma leading to better functional recovery.

Animals↗
PubMed2000

Changing heat and moisture exchangers after 96 hours rather than after 24 hours: a clinical and microbiological evaluation.

OBJECTIVE: The aim of this study was to determine whether changing heat and moisture exchangers (HMEs) every 96 hrs rather than 24 hrs would affect their efficacy to preserve the heat and moisture of inspiratory gases. The impact of a prolonged use of the HME on its microbial colonization was also assessed. DESIGN: Prospective cohort observational study. SETTING: Intensive care unit of a university hospital. PATIENTS: Thirteen consecutive patients with no previous history of respiratory disease requiring controlled mechanical ventilation with an HME for >4 days were evaluated. INTERVENTIONS: The same HME was used for 96 hrs in each patient. MEASUREMENTS AND MAIN RESULTS: In each patient, during the inspiration phase, the following measurements were performed: peak and mean airway pressures, mean values of temperature, and relative and absolute humidity of inspired gases. In each patient, measurements were performed after 1 hr of HME use and then daily up to the fourth day. On days 1 and 4, microbiological samples were obtained from the patients' bronchial secretions and the ventilator side of the HME. After 96 hrs of ventilation with the same HME, tracheal tube occlusion was never observed. Using the same HME for 96 hrs rather than 24 hrs did not affect its technical performances: temperature at 24 hrs: 32.2 +/- 1.5 degrees C (90.0 +/- 34.7 degrees F), at 96 hrs: 32.1 +/- 1.6 degrees C (89.8 +/- 34.9 degrees F); relative humidity at 24 hrs: 97.9 +/- 2%, at 96 hrs: 98.1 +/- 1.7%; absolute humidity at 24 hrs: 33.1 +/- 2.4 mg H2O/L, at 96 hrs: 33.0 +/- 2.5 mg H2O/L. This analysis was based on a total of 312 measurements performed on the 13 patients. Peak and mean airway pressures did not change during the 96-hr study period, with identical tidal and minute volumes in the study patients. On day 1, ten patients had a positive culture of their tracheal secretions at a colony count of > or = 10(3) colony forming units/mL. After 96 hrs of use with the same HME, only seven patients had a positive culture of their tracheal secretions. Cultures from the ventilator sides of the HMEs were all sterile (13/13) after 96 hrs of use. CONCLUSIONS: In patients free from previous chronic respiratory disorder and ventilated for neurologic reasons, changing the HME after 96 hrs rather than 24 hrs did not affect its technical performance in terms of heat and water preservation of ventilatory gases. There is also some indirect evidence of very little, if any, changes in the HME resistance. No bacterial colonization of the ventilator sides of the HMEs was observed after 96 hrs of use. However, other large clinical trials should be undertaken to confirm the safety of extending the time between HME changes.

Adult↗
PubMed2000

Relationship between vitamin D status and skin phototype in general adult population.

A link between bone mineral density and skin color has been reported recently, and pigmentation has been shown to affect cutaneous vitamin D production. In the present study, we investigated the relationship between phototype, global self-assessed sun exposure, geographical location and vitamin D serum levels in 1191 French adults. When the factors were analyzed separately, individuals with lower phototypes as well as those with lower sun exposure showed significantly lower levels of vitamin D than those with darker phototypes or those with higher sun exposure. However, when factors were analyzed as a whole, the vitamin D status was no longer linked with the phototype, but with sun exposure and geographical location. Since phototypes and global self-assessments of sun exposure were positively linked, our data suggest that lower vitamin D levels in fair-skinned individuals are due to their sun exposure behavior.

Adult↗
PubMed2000

[Vitamin D concentrations in blood and skin phototype in a general adult population in France].

INTRODUCTION: A link between bone mineral density and skin color has been reported recently, and pigmentation has been shown to affect cutaneous vitamin D production. In the present study, we investigated the relationship between phototype, global self assessed sun exposure, geographical location and vitamin D serum levels in 1191 French adults. METHODS: Three multiple linear regression analyses were performed. The two first analyses to test separately the effect of phototype, and the effect of sun exposure on the vitamin D levels. Then, a third model was constructed, using both factors and geographical location. RESULTS: When the factors were analyzed separately, individuals with lower phototype showed significantly lower levels of vitamin D than those with darker phototype, as well as, individuals with lower sun exposure showed significantly lower levels of vitamin D than those with higher sun exposure. However in the global model, which takes into account phototype and sun exposure simultaneously together with the region of residence, the vitamin D status was no longer linked with the phototype, but with sun exposure and geographical location. CONCLUSION: Since phototype and global self-assessment of sun exposure were positively linked, our data suggest that lower vitamin D levels in fair-skinned individuals are due to their sun exposure behavior.

Adult↗
PubMed1999

Differential effects of human erythroid burst stimulating activity (HuEBSA) on human cord blood burst forming units-erythroid (BFU-Es) as a function of their differentiation state.

An erythroid stimulating activity which promotes the growth of small bursts probably arising from mature burst forming units-erythroid (BFU-Es) of adult human bone marrow cells and called human erythroid burst stimulating activity (HuEBSA), was previously found in media conditioned by a fetal human kidney cell line. In the present work we report that adding HuEBSA to cultures did not increase the burst number but increased the size of bursts from cord blood (CB) cells. A similar observation was made using stem cell factor (SCF). However, a synergistic effect on the burst number was noted when both HuEBSA and SCF were introduced to cultures. We also noticed that CB erythroid progenitors pre-cultured with 5637-Conditioned Medium [as a source of burst promoting activity (BPA)] and erythopoietin (Epo) for 3 days could be stimulated by HuEBSA but not by SCF. Similar results were obtained when interleukin 3 (IL-3) was introduced with Epo to the pre-cultures. These results suggest that two different populations of erythroid progenitors coexist in cord blood, one is Epo- and IL-3-sensitive, the other solely Epo-sensitive. It also seems probable that HuEBSA acts on erythroid progenitors arising from the more immature erythroid population, since its stimulating activity was evident after a 3-day pre-culture of cord blood cells in Epo and IL-3.

Cell Differentiation↗
PubMed1999

Changing a hydrophobic heat and moisture exchanger after 48 hours rather than 24 hours: a clinical and microbiological evaluation.

OBJECTIVE: Complications following ventilation with dry and cold gases may be prevented by the use of artificial noses or heat and moisture exchangers, which are a solution to both the problems of humidification and heat preservation. The aim of the present study was to determine whether changing hydrophobic heat and moisture exchangers (HMEs) every 48 h rather than 24 h would affect their efficacy to preserve the heat and moisture of inspiratory gases. The impact of a prolonged use of the HME on its microbial colonization was also assessed. DESIGN: Prospective observational study. SETTING: ICU of a university hospital. PATIENTS: Twelve patients requiring controlled mechanical ventilation for more than 2 days were evaluated. INTERVENTIONS: The patients were ventilated with a heat and moisture exchanger (HME) (Maxipleat Filter, Europe Medical, France). The hydrophobic HME was placed between the Y-piece and the connecting tube and changed after 48 h of continuous use. Temperature (degree C), relative humidity (%) and absolute humidity (mgH2O/l) were obtained using the capacitive sensor principle. Bacterial colonization (tracheal secretions and ventilator side of the HME) were obtained on days 1 and 2. MEASUREMENTS AND RESULTS: After 48 h of ventilation with the same HME, tracheal tube occlusion was never observed. Using the same hydrophobic HME for 48 h rather than 24 h did not affect its technical performance: temperature at 24 h: 32.5 +/- 1.3 degrees C, at 48 h: 32.7 +/- 1.8 degrees C; relative humidity (RH) at 24 h: 99.0 +/- 1.4%, at 48 h: 99.0 +/- 1.4%; absolute humidity (AH) at 24 h: 34.0 +/- 2.4 mgH2O/l, at 48 h: 34.4 +/- 3.5 mgH2O/l. Peak and mean airway pressures did not change over the 48-h study period, with identical tidal and minute volumes in the study patients. Total respiratory heat losses were not modified during the 48-h study period (at 24 h: 152 +/- 47 cal/min, at 48 h: 149 +/- 65 cal/min). Evaporative and convective heat losses were not modified either. On day 1, eight patients had positive cultures of their tracheal secretions at a colony count of 10(3) or higher cfu/ml. After 48 h of use of the same HME, only six patients had a positive culture of their tracheal secretions. Cultures from the ventilator sides of the HMEs were all sterile (12/12) after 48 h of use. CONCLUSIONS: Changing the hydrophobic HME after 48 h rather than 24 h did not affect its technical performance in terms of heat and water preservation of ventilatory gases. There is also some indirect evidence of very little, if any, change in HME resistance. No bacterial colonization of the ventilator sides of the HMEs was observed after 48 h of use. However, other large clinical trials should be undertaken to confirm the safety of extending the time between HME changes.

Adult↗
PubMed1999

[Severe agranulocytosis induced by carbamazepine (Tegretol)].

We describe a case of severe drug-induced agranulocytosis, with the risk of a lethal outcome in a patient with a posttraumatic tetraplegia. Intercurrent complications required numerous medicaments. One month after admission, the neutrophil count decreased for ten days until a nadir of 70.mm-3, associated with an infectious syndrome. The bone marrow biopsy showed a severe granulocyte hypoplasia with absence of final differentiation. Administration of ienograstime (granulocyte stimulating factor) was efficient. In this patient, carbamazepine was the most probable causal factor for agranulocytosis. However, other medicaments, mainly antibiotics, could have been contributing factors.

Acinetobacter Infections↗
PubMed1999

Do the components of heat and moisture exchanger filters affect their humidifying efficacy and the incidence of nosocomial pneumonia?

OBJECTIVES: To compare the efficiency of two heat and moisture exchange filters (HMEFs) of different compositions of the humidifying capacity and the rate of bronchial colonization and ventilator-associated pneumonia in patients in the intensive care unit (ICU). DESIGN: Prospective, randomized study. SETTING: ICU of a university hospital. PATIENTS: All patients who required mechanical ventilation for 24 hrs or more during the study period. INTERVENTIONS: At admission to the ICU, patients were randomly assigned to one of two groups. In one group, the patients were ventilated with Humid-Vent Filter Light HMEF. The condensation surface was made of paper impregnated with CaCl2. The filter membrane was made of polypropylene. In the other group, the patients were ventilated with the Clear ThermAl HMEF (Intersurgical, France). The condensation surface was made of plastic foam impregnated with AlCl2. The filter membrane was made of two polymer fibers (modacrylic and polypropylene). In both groups, HMEFs were changed daily. MEASUREMENTS AND MAIN RESULTS: Seventy-seven patients were ventilated for 19+/-7 days with the Humid-Vent Filter Light HMEF and 63 patients for 17+/-6 days with the Clear ThermAl HMEF. Patients ventilated with the Humid-Vent Filter Light underwent 8.7+/-3.7 tracheal aspirations and 1.2+/-2.0 instillations per day and those with the Clear ThermAl, 8.2+/-3.9 and 1.5+/-2.4 per day, respectively (NS). The abundance of tracheal secretions and the presence of blood and viscosity, as evaluated by semiquantitative scales, were similar in both groups. One episode of tracheal tube occlusion was observed with the Humid-Vent Filter Light HMEF and none with the other HMEF (NS). Tracheal colonization was observed at a rate of 91% with the Humid-Vent Filter Light and 97% with the Clear ThermAl (NS). The rate of ventilator-associated pneumonia was similar in both groups (35%). Bacteria responsible for tracheal colonization and pneumonia were similar in both groups. CONCLUSIONS: Despite differences in their components, the two HMEFs that were tested achieved similar performances in terms of humidification and heating of inspired gases. Only one episode of endotracheal tube occlusion was detected, and very few patients (three in each group) had to be switched to an active heated humidifier. No difference was observed either in the rate of tracheal colonization or of ventilator-associated pneumonia. These data show that the Humid-Vent Filter Light and the Clear ThermAl HMEFs are suited for use with ICU patients.

Adult↗
PubMed1999

Effects of norepinephrine plus dobutamine or norepinephrine alone on left ventricular performance of septic shock patients.

OBJECTIVE: To determine the hemodynamic effects of the combination of norepinephrine-dobutamine in adult patients with septic shock. Specifically, we tested the hypothesis that norepinephrine in addition to dobutamine would improve cardiac index (CI) and stroke volume index (SVI) and increase left-ventricular afterload. DESIGN: Prospective, descriptive, interventional study with no control group. SETTING: Intensive care unit of a university hospital. PATIENTS: Fourteen patients (group 1) were transferred to the intensive care unit from other wards with septic shock not responsive to dobutamine infusion, low blood pressure (systolic blood pressure of <90 mm Hg), clinical and laboratory signs of infection, clinical signs of poor organ perfusion, and blood lactate of >2.0 mmol/L. They were enrolled and treated by the addition of norepinephrine, while the dose of dobutamine remained constant. Three of these patients required additional fluid loading to achieve adequate ventricular filling (pulmonary capillary wedge pressure [PCWP], 12-15 mm Hg). These patients were compared with 12 patients with septic shock with high CI (CI > 5/min/m2, and other signs as outlined previously) who were treated with norepinephrine alone (group 2). INTERVENTIONS: Patients in group 1 were maintained with the same dobutamine dose, and norepinephrine was added (initial dose, 0.5 microg/kg/min, and increments of 0.3 microg/kg/min) until the correction of mean arterial blood pressure (MAP > or =75 mm Hg). Patients in group 2 received norepinephrine following the same protocol. MEASUREMENTS AND MAIN RESULTS: At study entry, group 1 patients receiving dobutamine had similar MAPs but were significantly older and had significantly lower CIs and SVIs and higher systemic vascular resistance than group 2 patients. In group 1 norepinephrine, in addition to dobutamine, significantly increased MAP, CI, SVI, left ventricular stroke work index (LVSWI), and systemic vascular resistance (SVR). No change in heart rate or PCWP was observed. In group 2, norepinephrine used alone did not modify CI or SVI and it significantly improved MAP, LVSWI, and SVR. No changes in heart rate or PCWP were observed. Blood lactate was significantly decreased in both groups. Comparing the two groups, in response to norepinephrine titrated to increase MAP to a similar concentration, patients with dobutamine-resistant septic shock had a statistically significantly greater increase in CI and SVI than patients treated with norepinephrine alone. There were no other significant differences in hemodynamic and metabolic responses to norepinephrine between groups 1 and 2. CONCLUSION: The addition of norepinephrine to treatment of patients with septic shock unresponsive to dobutamine significantly improves MAP, CI, SVI, and LVSWI. A different pattern of evolution was observed if norepinephrine was used alone in younger patients with higher CI at study entry, increases in MAP and LVSWI, and no concomitant change in CI or SVI. The use of norepinephrine in dobutamine-resistant septic shock may have some beneficial implications for the treatment of patients with inadequate myocardial performance associated with low SVR.

Adrenergic alpha-Agonists↗
PubMed1998

Mona, a novel hematopoietic-specific adaptor interacting with the macrophage colony-stimulating factor receptor, is implicated in monocyte/macrophage development.

The production, survival and function of monocytes and macrophages are regulated by the macrophage colony-stimulating factor (M-CSF or CSF-1) through its tyrosine kinase receptor Fms. Binding of M-CSF results in Fms autophosphorylation on specific tyrosines that act as docking sites for intracellular signaling molecules containing SH2 domains. Using a yeast two-hybrid screen, we cloned a novel adaptor protein which we called 'Mona' for monocytic adaptor. Mona contains one SH2 domain and two SH3 domains related to the Grb2 adaptor. Accordingly, Mona interacts with activated Fms on phosphorylated Tyr697, which is also the Grb2-binding site. Furthermore, Mona contains a unique proline-rich region located between the SH2 domain and the C-terminal SH3 domain, and is apparently devoid of any catalytic domain. Mona expression is restricted to two hematopoietic tissues: the spleen and the peripheral blood mononuclear cells, and is induced rapidly during monocytic differentiation of the myeloid NFS-60 cell line in response to M-CSF. Strikingly, overexpression of Mona in bone marrow cells results in strong reduction of M-CSF-dependent macrophage production in vitro. Taken together, our results suggest an important role for Mona in the regulation of monocyte/macrophage development as controlled by M-CSF.

Adaptor Proteins, Signal Transducing↗
PubMed1998

D2AM, a beamline with a high-intensity point-focusing fixed-exit monochromator for multiwavelength anomalous diffraction experiments.

D2AM is a french CRG beamline installed at the ESRF (European Synchrotron Radiation Facility) in Grenoble, with half of the time dedicated to biological macromolecule crystallography and half to materials science studies (diffraction, wide-angle and small-angle scattering). It is constructed at the front-end BM02 of the ESRF storage ring, using the X-ray beam from a 0.8 T bending magnet. D2AM entered into routine operation at the end of 1994, and is used either for single-wavelength or for multiwavelength anomalous diffraction studies. The beam is monochromated by an Si[111] two-crystal monochromator with a resolution of about 2 x 10(-4). The first crystal is water cooled. The X-ray photon energy covers the range between 6.5 keV (lambda approximately 1.9 A) and 17 keV (lambda approximately 0.7 A), a domain of energy with many K or L absorption edges of heavy atoms of interest for biological macromolecules studies and in materials science. The X-ray beam is focused in the vertical plane by two long curved mirrors and in the horizontal plane by the second crystal of the monochromator which is given an adjustable sagittal curvature. A spot size of 0.3 x 0.1 mm (FWHM) is measured at the sample position. Both mirrors are cut out of a 6"-diameter 1.1 m-long Si single crystal, polished and coated with a 400 A Pt thin film. The rugosity is better than 4 A r.m.s. and the longitudinal slope error is better than 5 x 10(-6) rad r.m.s. The first mirror is water cooled, the second is not. The beam intensity on the sample is about 10(11) photon s(-1) on a 0.3 x 0.3 mm focus area at 100 mA in the storage ring of the ESRF. The harmonic rejection ratio obtained with the two mirrors is better than 10(-5) for lambda/3. The combined optical system, mirror/monochromating-crystals/mirror, used on D2AM constitutes altogether a high-intensity point-focusing fixed-exit monochromator, which has the additional property that the energy resolution is not dependent on the beam divergence in use. Its stability and resolution are perfectly adapted to multiwavelength anomalous diffraction studies. The alignment of the mirrors and the monochromator is fully automated, taking 5 min, with the exception of the adjustment of the sagittal focusing. During multiwavelength diffraction experiments the wavelength is changed by a fast single monochromator rotation. Neither realignment of the mirrors nor readjustment of the beam focusing are necessary. The stability and reproducibility of the selected X-ray photon energy is better than 0.5 eV.

Journal Article↗
PubMed1998

A human cell line isolated from fetal kidney produces an apparently erythroid-specific stimulating activity.

The burst formation from human and murine burst forming unit-erythroid (BFU-E) requires the presence of erythropoietin (Epo) in semi-solid cultures of bone marrow cells. A number of haematopoietic factors are described that increase the burst number: interleukin 3 (IL-3), stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-9, IL-11, insulin-like growth factor I, and erythroid potentiating activity (EPA). The authors now show that another activity present in medium conditioned from adult or fetal human kidney cells specifically stimulates the proliferation of BFU-E. A cell line derived from fetal kidney produced such an activity, which was shown to be different from the previously cited haematopoietins, acted on CD34(+)-enriched BFU-E and promoted an increase in CFU-E number in the bone marrow of injected animals, could be precipitated using 40% ammonium sulfate, was destroyed by proteolytic enzymes and was shown to be a glycoprotein by its retention on ConA-Sepharose. The authors propose to call this apparently novel activity, which influences only the number of bursts, human erythroid burst-stimulating activity (hEBSA).

Adult↗
PubMed1998

Nitric oxide production and perivascular tyrosine nitration following focal ischemia in neonatal rat.

Oxygen free radicals and nitric oxide (NO.) have been proposed to be involved in acute CNS injury produced by cerebral ischemia; however, controversy remains regarding how they cause injury. Because superoxide generation is triggered during reperfusion, the cytotoxic oxidant peroxynitrite could be formed, but it is not known if this occurs. Dot blot and immunohistochemistry studies were performed on the magnitude and time course of tyrosine nitration and inducible NO synthase (NOS2) in the postischemic rat pup brain. Neonatal ischemia was induced by permanent left middle cerebral artery occlusion in association with 1-h occlusion of the left common carotid artery in 7-day-old Wistar pups. Nitrotyrosine (NT) immunoreactivity was evident in the blood vessels close to the cortical infarct at 48-72 h of recovery, and T lymphocytes were involved with this production. NOS2 immunoreactivity was seen in neutrophils in the same vessels and in the parenchyma at 72 h of recirculation. Whereas NT staining decreased with time, NOS2-positive neutrophils could be still detected in arachnoid vessels at 14 days of recirculation. We conclude that perivascular reactions mediated by peroxynitrite are important in the cascade of events that lead to brain oxidative stress in neonatal ischemia. Moreover, NO-related species may serve as a signaling function instead of directly mediating toxicity.

Animals↗
PubMed1998

Preservation of humidity and heat of respiratory gases in spontaneously breathing, tracheostomized patients.

BACKGROUND: Ventilation with endotracheal intubation bypasses the upper airway and the normal heat and moisture exchanging process of inspired gases. A continuous loss of moisture and heat occurs and predisposes patients to serious airway damage. We therefore prospectively studied one heated humidifier system, one cold humidifier system and one heat and moisture exchanger in spontaneously breathing, tracheostomized intensive care unit patients to determine the ability to preserve patients' heat and water. METHODS: Following a randomized order, 10 patients were spontaneously ventilated for 24-h periods with the Nam 35 humidifier (Europe Medical, France, a cold water humidifier), the heat and moisture exchange Trach-Vent (Gibeck, Sweden), and the Aerodyne humidifier (Kendall USA). In each patient, during the inspiration phase, the following measurements were performed: mean values of temperature and relative humidity of inspired gases. The absolute humidity was calculated. Values were obtained in each patients after 40 min and 24 h. RESULTS: The Trach-Vent filter and the Aerodyne humidifier had better humidification and thermic capacities than the Nam 35 humidifier (P < 0.001). With the Nam 35 humidifier, no patient had temperature of inspired gas > 29 degrees C. Concerning absolute humidity of inspired gases, the Nam 35 humidifier achieved a lower performance than the other two tested systems (P < 0.001). CONCLUSION: In spontaneously breathing, tracheostomized intensive care unit patients, the Trach-Vent heat and moisture exchanger and the Aerodyne heated system achieved satisfactorily preservation of heat and humidity of inspired gases.

Body Temperature↗
PubMed1998

Comparing two heat and moisture exchangers, one hydrophobic and one hygroscopic, on humidifying efficacy and the rate of nosocomial pneumonia.

OBJECTIVE: Many heat and moisture exchangers with filter (HMEF) have been developed. In-house data from companies provide some information about their performances; unfortunately, to our knowledge, no comparative evaluation in clinical conditions has been undertaken of these newer products. The aim of this study was to compare the efficiency of two HMEFs, one hydrophobic and one hygroscopic, on humidifying capacity and the rate of bronchial colonization and ventilator-associated pneumonia in ICU patients. DESIGN: Prospective, randomized study. SETTING: ICU of a university hospital. PATIENTS: All patients who required mechanical ventilation for > or = 24 h during the study period. INTERVENTIONS: On admission to the ICU, patients were randomly assigned to one of two groups. In one group, the patients were ventilated with a hygroscopic device (Humid-Vent Filter Light HMEF; Gibeck; Upplands Vaesby, Sweden). The condensation surface was made of paper (Microwell) impregnated with CaCl2. The filter membrane was made of polypropylene. In the other group, the patients were ventilated with a hydrophobic device (Pall BB100 HMEF). The condensation surface was made of a hydrophobic resin with a hydrophylic layer. The filter membrane was made of ceramic fibers. In both groups, HMEFs were changed daily. MEASUREMENTS AND RESULTS: Both groups of patients were similar for the tested characteristics, including parameters of mechanical ventilation. Sixty-six patients were ventilated for 11.7+/-11 days with the Humid-Vent Filter Light HMEF and 70 patients for 12.2+/-12 days with the Pall BB 100. Patients ventilated with the Humid-Vent Filter Light underwent 6.0+/-3.0 tracheal aspirations and 1.7+/-2.0 instillations per day, and those with the Pall BB 100, 6.0+/-3.0 and 1.6+/-2.0 per day, respectively (not significant [NS]). Abundance of tracheal secretions, presence of blood, and viscosity, evaluated by semiquantitative scales, were similar in both groups. No difference in the rate of atelectasis was observed between the two groups (7.5% and 7.1%, NS). One episode of tracheal tube occlusion was observed with the Humid-Vent Filter Light HMEF, and one with the other HMEF (NS). One patient in each group (NS) was switched to an active heated humidifier because of very tenacious bronchial secretions despite repeated instillations. Tracheal colonization was observed at a rate of 67% with the Humid-Vent Filter Light and 58% with the Pall BB 100 (NS). A small, but NS difference was observed in the rate of ventilator-associated pneumonia: Humid-Vent Filter Light, 32% (27.1 per 1000 ventilator days); and Pall BB 100, 37% (30.4 per 1000 ventilator days). Bacteria responsible for tracheal colonization and pneumonia were similar in both groups. Three patients in each group died from their nosocomial pneumonia. CONCLUSION: Despite differences in their components, the two HMEFs tested achieved similar performances in terms of humidification and heating of inspired gases. Only one episode of endotracheal tube occlusion was detected and very few patients (one in each group) had to be switched to an active heated humidifier. No difference was observed either in the rate of tracheal colonization or of ventilator-associated pneumonia. These data show that the hygroscopic HME (Humid-Vent Filter Light) and the hydrophobic HME (Pall BB 100) are suited for use in ICU patients.

Adult↗
PubMed1998

[Therapeutic approach of French practitioners to rectal cancer].

OBJECTIVES: Improvements in treatment of rectal cancer have enabled a better control of locoregional disease. Our objective was to describe the therapeutic decisions of different specialists implied through clinical cases and the influence of their professional characteristics. METHODS: In spring 1996, a questionnaire was mailed to a random sample of 621 French physicians, presenting 3 clinical cases of rectal cancer at different stages. The present analysis deals with a clinical case concerning a 46 year-old man bearing a T3N0 tumor, at 7 cm from the anal verge. Statistical analysis (uni and multivariate, by logistic regression) was performed with SPSS software. RESULTS: Three hundred fifty two exploitable responses were returned (response rate: 57%). Half of the physicians chose a pluridisciplinary decision modality. There were differences according to the speciality (P < 0.003), to the type of practice (public/private) (P < 10(-4)) and to the proximity of specialized units (P = 0.03). Therapeutic attitudes consisted in a combination of radiotherapy and surgery (RT-SU) for 95% of the physicians. The therapeutic choice was in agreement with the French consensus conference for 71% of physicians. Two main attitudes emerged for this clinical case: exclusive RT-SU combination (43.5%) and RT-SU with optional or systematic chemotherapy (CT) (52%). The latter choice appeared to be closely dependent on medical speciality (P = 0.0004) and background (P = 0.002). CONCLUSION: Decision making is mainly related to the place of work, whereas the therapeutic attitude depends on physicians' own characteristics. Until 1990, multiple therapeutic options for rectal cancer were performed in France. Nowadays, for a T3N0 tumor, the argumentation is rather focused on the indication of CT combined with the standard RT-SU treatment. Results from ongoing controlled studies will help update consensual recommendations.

Adult↗