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J Chastre

Publications and source records attributed to J Chastre.

At least 19 recordsLinked to original sources
PubMed1995

Early infective endocarditis on prosthetic valves.

Despite major advances in cardiovascular surgical techniques and routine use of prophylactic antimicrobial agents, prosthetic valve endocarditis (PVE) continues to complicate the course of a small percentage of patients after cardiac valve replacement. Using actuarial methods to describe the risk of PVE after valve implementation, several studies have shown that its incidence peaked at around 5 weeks and levelled off to a stable rate by 12 months, for a cumulative risk of 3% at that time. The microbial aetiology of early PVE is dominated by staphylococcal species, S. epidermis and S. aureus accounting for about 30% and 20% of cases, respectively, even though prophylactic regimens used today are targeted against these microorganisms. In nearly all patients, infection spread behind the site of attachment of the valve prosthesis, resulting in valve ring abscesses and valve dehiscence in 60% of cases. Valve obstruction by vegetations is much more uncommon except in patients with mitral or tricuspid valve endocarditis. The clinical course of early PVE tends to be frequently fulminant, with rapid deterioration of the haemodynamic status due to valvular or annular destruction or persistent bacteraemia. In some cases, however, the classic symptoms of endocarditis may be less noticeable because signs related to an initial source of bacteria, such as sternotomy wound infection, may be more prominent. While various non-invasive and invasive studies have been proposed to aid in the diagnosis of PVE, transoesophageal echocardiography is now the technique of choice for that purpose, as well as for detecting prosthetic valve dysfunction and other intracardiac complications of PVE.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Bacterial Agents↗
PubMed1995

Evaluation of bronchoscopic techniques for the diagnosis of nosocomial pneumonia.

To compare the usefulness of specimens obtained by bronchoalveolar lavage (BAL) and using a protected specimen brush (PSB) in the diagnosis of nosocomial pneumonia, both procedures were performed via fiberoptic bronchoscopy just after death in a series of 20 ventilated patients who had not developed pneumonia before the terminal phase of their disease and who had no recent changes in antimicrobial therapy. These results were compared with both histologic and microbiologic postmortem lung features in the same area. The total number of bacteria obtained by culture of lung segments and the latters' histologic grade were closely correlated (rho = 0.79, p < 0.0001). PSB and BAL quantitative culture results were strongly correlated with lung tissue values (rho = 0.67 and 0.75, respectively; p < 0.0001). Using discriminative values of > or = 10(3) and > or = 10(4) bacteria/ml to define positive PSB and BAL cultures, respectively, these techniques identified lung segments yielding > or = 10(4) bacteria/g tissue with sensitivities of 82 and 91% and specificities of 89 and 78%, respectively. Moreover, upon direct observation, the percentage of BAL cells containing intracellular bacteria was closely correlated with the total number of bacteria obtained from corresponding lung samples (p < 0.001). These findings indicate that bronchoscopic PSB and BAL samples very reliably identify both qualitatively and quantitatively microorganisms present in lung segments with bacterial pneumonia, even when the infection develops as a superinfection in a patient already receiving antimicrobial treatment for several days.

Aged↗
PubMed1995

Role of quantitative cultures of endotracheal aspirates in the diagnosis of nosocomial pneumonia.

To assess the reliability of quantitative cultures of endotracheal aspirates (EA) to diagnose ventilator-associated pneumonia, fiberoptic bronchoscopy was used to study 57 episodes of suspected lung infection in 39 patients with no recent changes in antimicrobial chemotherapy. A total of 19 cases (33%) of pneumonia were diagnosed based on the following criteria: protected specimen brush (PBS) sampling yielding > or = 10(3) cfu/ml of at least one microorganism and/or > or = 5% of cells containing intracellular bacteria on direct examination of bronchoalveolar lavage (BAL). The operating characteristics of EA cultures were calculated over a range of cutoff values (from 10(3) to 10(7) cfu/ml), and the threshold of 10(6) cfu/ml appeared to be the most accurate, with a sensitivity of 68% and a specificity of 84%. Microorganisms cultured from EA samples correlated weakly with those obtained using PSB specimens (rho = 0.32), with only 49 microorganisms among 123 (40%) found in both samples. These latter results and the relatively low sensitivity of the technique indicate that EA quantitative cultures are of limited value for the diagnosis of pneumonia in ventilated patients when fiberoptic techniques are available.

Anti-Bacterial Agents↗
PubMed1993

Characterization of intensive care unit patients using a model based on the presence or absence of organ dysfunctions and/or infection: the ODIN model.

OBJECTIVE: To evaluate the sensitivity, specificity and overall accuracy of a model based on the presence or absence of organ dysfunctions and/or infection (ODIN) to predict the outcome for intensive care unit patients. DESIGN: Prospective study. SETTING: General intensive care unit in a university teaching hospital. PATIENTS: 1070 consecutive, unselected patients. INTERVENTIONS: There were no interventions. MEASUREMENTS AND MAIN RESULTS: We recorded within the first 24 h of admission the presence or absence of dysfunction in 6 organ systems: respiratory, cardiovascular, renal, hematologic, hepatic and neurologic, and/or infection (ODIN) in all patients admitted to our ICU, thus establishing a profile of organ dysfunctions in each patient. Using univariate analysis, a strong correlation was found between the number of ODIN and the death rate (2.6, 9.7, 16.7, 32.3, 64.9, 75.9, 94.4 and 100% for 0, 1, 2, 3, 4, 5, 6 and 7 ODIN, respectively; (p < 0.001). In addition, the highest mortality rates were associated with hepatic (60.8%), hematologic (58.1%) and renal (54.8%) dysfunctions, and the lowest with respiratory dysfunction (36.5%) and infection (38.3%). For taking into account both the number and the type of organ dysfunction, a logistic regression model was then used to calculate individual probabilities of death that depended upon the statistical weight assigned to each ODIN (in the following order of descending severity: cardiovascular, renal, respiratory, neurologic, hematologic, hepatic dysfunctions and infection). The ability of this severity-of-disease classification system to stratify a wide variety of patients prognostically (sensitivity 51.4%, specificity 93.4%, overall accuracy 82.1%) was not different from that of currently used scoring systems. CONCLUSIONS: These findings suggest that determination of the number and the type of organ dysfunctions and infection offers a clear and reliable method for characterizing ICU patients. Before a widespread use, this model requires to be validated in other institutions.

Aged↗
PubMed1993

Follow-up protected specimen brushes to assess treatment in nosocomial pneumonia.

To prospectively determine the bacteriologic and clinical efficacy of antimicrobial therapy for nosocomial bacterial pneumonia selected based upon information provided by cultures of protected specimen brush (PSB) samples obtained during bronchoscopy, 76 consecutive patients with ventilator-associated pneumonia were studied using follow-up quantitative PSB cultures obtained after 3 days of treatment. Of the 173 microorganisms initially present in the PSB samples, only 11 (6%) were not eradicated by antimicrobial therapy, including three recovered at high (> or = 10(3) cfu/ml) concentrations. Thirty-two emerging pathogens, including nine at high concentrations, were also detected; 26 of them (81%) were resistant to the initial antibiotics administered. Of the 76 patients included in the study, cultures of follow-up PSB samples identified 51 in whom the infection site in the lung was completely sterilized, 16 with low-grade infection, and only nine with persistent high-grade infection. Analysis of clinical outcome within the 15 days after the initiation of antimicrobial therapy demonstrated clinical improvement in 62 of 67 (93%) patients in whom the site of infection was contained by treatment as compared with four of 9 (44%) patients with persistent high-grade infection (p < 0.01). These data suggest that appropriate antimicrobial therapy for ventilator-associated pneumonia results in the control of the initial infection in 88% of the patients. However, an early superinfection caused by multiresistant pathogens can occur in a small subset of these patients. When follow-up PSB cultures were negative, an improved outcome was noted.

Adolescent↗
PubMed1993

Pilot study of cardiopulmonary risk from pentoxifylline in adult respiratory distress syndrome.

Neutrophils and cytokines are directly involved in the pathophysiology of adult respiratory distress syndrome (ARDS). Pentoxifylline (PTX) has been shown in vitro to protect against the inflammatory effects of neutrophils and cytokines. The same protective effects have been demonstrated on animal models of lung injury. These results suggested that PTX might be useful in patients with ARDS. The cardiopulmonary effects of large doses of PTX were evaluated in a pilot study performed in six patients with severe ARDS. PTX was administered with an initial 1-mg/kg bolus, followed by infusion of 1.5 mg/kg/h over 6 h. No significant change was observed in the gas exchange and hemodynamic parameters, except for a 10 percent increase in the heart rate during the infusion period. Our results demonstrate that large doses of PTX induced only minor hemodynamic changes without worsening in pulmonary gas exchange. Further studies are warranted to evaluate human safety and ultimately the effectiveness of PTX in the treatment of ARDS.

Aged↗
PubMed1992

Procedures for the diagnosis of pneumonia in ICU patients.

The optimal technique for diagnosing nosocomial bacterial pneumonia in critically ill patients cared for in the intensive care unit remains unclear, especially in the subgroup of patients requiring mechanical ventilation. An important advance has been the development of the protected specimen brush technique. Secretions obtained using this technique and evaluated by quantitative cultures are useful in distinguishing patients with and without pneumonia. However, this procedure has important limitations in that results are not available immediately, and in that a few false negative of false positive results may occur. Bronchoalveolar lavage has been suggested to be of value in establishing the diagnosis of pneumonia, because the cells and liquid recovered can be examined microscopically immediately after the procedure and are also suitable for quantitative culture. Microscopic identification of bacteria within cells recovered by lavage may provide a sensitive and specific means for the early and rapid diagnosis of pneumonia in this setting. The lavage technique can also be conveniently incorporated into a protocol along with quantitative culture of samples obtained using the protected specimen brush. This combination will probably improve the overall accuracy of diagnosis while allowing the administration of prompt empiric antimicrobial therapy in most patients with pneumonia.

Bacteriological Techniques↗
PubMed1991

Spontaneous release of granulocyte colony-stimulating factor (G-CSF) by alveolar macrophages in the course of bacterial pneumonia and sarcoidosis: endotoxin-dependent and endotoxin-independent G-CSF release by cells recovered by bronchoalveolar lavage.

Because granulocyte colony-stimulating factor (G-CSF) is known to induce granulopoiesis and activate mature neutrophils, this factor could be important in determining the number and functional activity of neutrophils at sites of lung disease. The purpose of this study was to evaluate the ability of lung immune and inflammatory cells to produce G-CSF, and to seek evidence for the spontaneous production of this factor by cells recovered by lavage from controls and patients with lung diseases in which neutrophils may play a pathogenetic role. Lavage cells from controls produced little G-CSF spontaneously. Alveolar macrophages (AM), but not lymphocytes, produced large amounts following endotoxin stimulation. Lavage cells from patients with respiratory failure associated with bacterial pneumonia, but not those with respiratory failure from noninfectious causes, spontaneously released G-CSF (32 +/- 24 and less than 1 U/10(6) AM, respectively). Lavage cells from five of 15 patients with sarcoidosis and one of five patients with diffuse pulmonary fibrosis also spontaneously released G-CSF, which could not be explained by endotoxin exposure. The release of G-CSF by endotoxin-dependent and -independent mechanisms could play a role in the recruitment and activation of neutrophils in bacterial pneumonia and participate in the pathogenesis of some interstitial lung diseases.

Adult↗
PubMed1991

[Necrotizing fasciitis of the upper limb. 12 cases].

Twelve cases of necrotizing fasciitis or streptococcal cellulitis of the upper limb are reported. Four cases presented with a low grade aggressive for and one case was chronic. Seven fulminating cases resulted in two deaths. These different presentations are in fact different stages of the same disease which is a group A beta-hemolytic streptococcal necrotizing infection of the subcutaneous tissue. It is a medical emergency in which surgery is the main treatment. In cases seen early, surgery helps by making an early diagnosis by showing the typical appearance of the subcutaneous tissue and by isolating organisms in wound culture. In fulminant cases, only extensive surgical debridement can control infection. Delayed or incomplete radical excision may lead to disseminated infection. Infection spreading beyond one upper limb worsens the vital prognosis.

Adult↗
PubMed1990

Bronchoalveolar lavage for rapid diagnosis of the fat embolism syndrome in trauma patients.

OBJECTIVE: To evaluate the usefulness of bronchoalveolar lavage in establishing the diagnosis of the fat embolism syndrome in trauma patients with long-bone fractures. DESIGN: Case series. SETTING: Referral hospital. PATIENTS: Eighteen trauma patients with long-bone fractures, including 5 with definite fat embolism syndrome, 5 in whom the diagnosis had been clinically suspected but was impossible to confirm or exclude before bronchoscopy, and 8 with no clinical evidence of the syndrome. Control groups included 9 patients without previous trauma who developed the adult respiratory distress syndrome for various reasons and 15 normal volunteers. MEASUREMENTS AND MAIN RESULTS: Each patient had fiber-optic bronchoscopy with bronchoalveolar lavage, and the percentage of lavage cells containing intracellular fat droplets stained with oil red 0 were determined. In the five patients with definite fat embolism syndrome, light microscopic study of bronchoalveolar cells stained with oil red 0 showed many large intracellular fat droplets (mean percentage of cells containing fat droplets, 63%; range, 31% to 82%), whereas less than 2% of cells recovered by lavage from trauma patients with no clinical evidence of the syndrome, from patients with the adult respiratory distress syndrome, or from normal volunteers contained such inclusions. Use of the same technique in the five patients with possible fat embolism syndrome permitted the immediate identification of three patients in whom this diagnosis was later confirmed by subsequent autopsy or clinical follow-up. CONCLUSIONS: The identification of fat droplets within cells recovered by bronchoalveolar lavage in trauma patients may be a rapid and specific method for establishing the diagnosis of the fat embolism syndrome.

Adolescent↗
PubMed1990

Abnormal epithelial cells recovered by bronchoalveolar lavage: are they malignant?

The recovery of neoplastic cells by bronchoalveolar lavage is useful in the diagnosis of lung cancer. Abnormal epithelial cells can also be recovered from patients with interstitial lung diseases who do not have cancer, and therefore the usefulness of lavage in the diagnosis of malignancy in this setting is unknown. In this study, we evaluated the diagnostic significance of abnormal lavage cells recovered from patients with diffuse parenchymal abnormalities and compared the usefulness of standard cytologic assessment, correlation with clinical features, and immunocytochemical staining for carcinoembryonic antigen (CEA) in identifying abnormal cells that are truly malignant. Thirty of 2,314 patients had atypical lavage cells, but in only nine was lung cancer demonstrated. Although most patients with clinical suspicion of malignancy had lung carcinoma (six of seven), one such patient did not have cancer, and three were shown to have unsuspected carcinoma. Cytologic criteria identified definitely malignant cells in only four of nine patients with lung cancer, indicating that the approach is not sensitive. Immunostaining of abnormal cells with anti-CEA antibodies proved helpful. All patients with lung malignancy had CEA+ cells (n = 9), and no patient whose abnormal cells were CEA- proved to have cancer (n = 17). Because only nine of 13 patients with CEA+ cells had lung malignancy, the test is not diagnostic, but it appears to limit the need for further evaluation to a smaller group of patients in whom cancer is likely to be present. When used together, cytopathologic findings, detection of CEA by immunocytochemical techniques, and clinical correlates proved useful in diagnosis of lung malignancy, but further improvements are still needed to improve diagnostic accuracy.

Bronchoalveolar Lavage Fluid↗
PubMed1990

Characterization of distal bronchial microflora during acute exacerbation of chronic bronchitis. Use of the protected specimen brush technique in 54 mechanically ventilated patients.

To obtain accurate information on distal bronchial microflora during acute exacerbation in patients with chronic bronchitis, we prospectively studied 54 such patients who had been receiving mechanical ventilation because of hypercapnic respiratory failure. Fiberoptic bronchoscopy using a protected specimen brush (PSB) was performed on each patient within the first 24 h after admission. Cultures of protected brush specimens demonstrated no growth in 27 patients (50%). With the exception of fever (38.2 +/- 0.8 versus 37.7 +/- 0.6 degrees C; p less than 0.05), the initial severity of the episode of exacerbation was similar in patients with and without infection. A total of 44 organisms were isolated in the 27 patients with positive cultures; the predominant pathogens were Hemophilus spp. and Streptococcus spp. (involved in 74% of cases), but other organisms were isolated in 12 of 27 patients. Mortality rates, duration of mechanical ventilation, and duration of hospitalization were not significantly different between patients with bronchial microflora treated with appropriate antimicrobial therapy (n = 27) and patients without bronchial microflora either receiving empirical antibiotic therapy (n = 18) or not (n = 9). These data suggest that distal bronchial infection due to the usual pathogens, as far as shown by protected specimen brush cultures, may not be the sole or even the predominant cause of acute exacerbation of chronic bronchitis in patients requiring mechanical ventilation.

Acute Disease↗
PubMed1990

Incidence and morbidity of cytomegaloviral infection in patients with mediastinitis following cardiac surgery.

To determine the incidence and morbidity of infections with CMV associated with mediastinitis after conventional cardiac surgery, 115 consecutive adult patients with mediastinitis were evaluated with viral cultures of blood and urine. Shedding of CMV was seen in 29 patients (25 percent) within a mean period of 37 +/- 22 days after cardiopulmonary bypass. Viremia was documented in 79 percent (23) of these 29 patients. Acute renal failure and enzymatic abnormalities (AST and LDH) were significantly more common in patients with virologically proven infection with CMV (p less than 0.05). In patients who survived the initial period of bacterial infection, major differences in their clinical course were observed according to their virologic status. After the 15th day of hospitalization following the débridement, the persistence of local infection was more frequent (p less than 0.05) and the mortality was higher (p less than 0.01) in CMV-infected patients. Moreover, the mean duration of hospitalization in the ICU for survivors was 69 +/- 36 days in viral shedders, compared with 48 +/- 27 days in nonshedders (p less than 0.05). Infection with CMV in mediastinitis occurs frequently and is associated with persistence of local infection, prolonged hospitalization, and increased late mortality.

Antibodies, Viral↗
PubMed1990

Fiberoptic bronchoscopy in ventilated patients. Evaluation of cardiopulmonary risk under midazolam sedation.

One hundred seven acutely ill ventilated patients were prospectively studied to ascertain the severity and frequency of alterations in gas exchange and hemodynamic parameters during brief bronchoscopy. Sedation was performed using midazolam (0.1 mg/kg IV) without topical anesthesia. An average decline in PaO2 of 26 percent was observed at the end of the procedure, compared to the baseline value, and this was associated with a mild increase in PaCO2 in spite of the use of a special adapter. Alterations in mean systolic blood pressure appeared to be modest, consisting of a 10 percent decrease from the control level, related to sedation, and a 10 percent rise from baseline during the procedure, associated with a concomitant mild tachycardia. At that time, central hemodynamic measurements performed in a subset of 31 patients showed a significant increase in cardiac output associated with higher pulmonary wedge pressure. Fourteen patients developed hypoxemia of less than 60 mm Hg on FIO2 adjusted to 0.8. Of the ten risk factors univariately associated with hypoxemia, only the presence of ARDS (p less than 0.001) and "fighting" the ventilator during the procedure (p less than 0.05) remained significant after stepwise logistic regression. Attempts to prevent hypoxemia in critically ill patients should focus on inducing complete sedation, with careful attention to hemodynamic status, or providing maximal levels of oxygen to the ventilator (or both).

Adult↗