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J Chastre

Publications and source records attributed to J Chastre.

At least 19 recordsLinked to original sources
PubMed1997

Usefulness of quantitative cultures of BAL fluid for diagnosing nosocomial pneumonia in ventilated patients.

STUDY OBJECTIVE: To evaluate the role of quantitative cultures of BAL for diagnosing nosocomial pneumonia in mechanically ventilated patients. DESIGN: Cohort study. SETTING: Medical ICU, Hôpital Bichat, Paris, France, an academic tertiary care center. PATIENTS: A total of 141 episodes of suspected lung infection in 84 consecutive patients mechanically ventilated for 48 h or more. MEASUREMENTS AND RESULTS: Microbiologic findings obtained using BAL were compared with those obtained with protected specimen brush (PSB) samples and their operating characteristics were determined. The level of qualitative agreement between BAL and PSB specimen cultures was high, with 83% of the organisms isolated in PSB specimens being recovered simultaneously from BAL fluid. In addition, the results of quantitative BAL and PSB cultures were significantly correlated (rho = 0.46, p < 0.0001). Fifty-seven cases of pneumonia were diagnosed based on the following criteria: PSB sample yielding > or = 10(3) cfu/mL of at least one microorganism and/or > or = 5% of cells containing intracellular bacteria on direct examination of BAL. The operating characteristics of BAL fluid cultures were determined using different ways to report the results and over a range of values. The discriminative value of 10(4) cfu/mL was found to be an optimal threshold, with a sensitivity of 82% (95% confidence interval [CI], 76 to 88) and a specificity of 84.5% (95% CI, 79 to 90). CONCLUSIONS: These results indicate that BAL fluid cultures can offer a sensitive and specific means to diagnose pneumonia in ventilated patients and may provide relevant information about the causative pathogens.

Adult↗
PubMed1996

[Nosocomial pneumonia in intensive care units].

Nosocomial pneumonia is associated with substantial morbidity and mortality. Patients treated with mechanical ventilation have the highest risk for developing this intensive care unit acquired infection. Gram-negative bacilli are the predominant organisms responsible for pneumonia in this setting. However, Staphylococcus aureus has recently emerged as a significant isolate. Nosocomial pneumonia is difficult to diagnose clinically in ventilated patients because fever, lung infiltrate on chest X-ray, leukocytosis are frequent in severely ill patients under mechanical ventilation whatever lung infection is present or not and because lower respiratory tract of such patients is colonized by potentially pathogenic bacteria independently of the presence of true lung infection; thus, different diagnostic strategies are proposed. Our personal bias is that using bronchoscopic techniques to obtain bronchoalveolar lavage and protected-brush specimens permits us to devise a therapeutic strategy that is superior to one based only on clinical evaluation. Measures for prevention of nosocomial infection are essential to decrease the incidence of nosocomial pneumonia and the emergence of multiresistant pathogens.

Cross Infection↗
PubMed1996

Nosocomial pneumonia and mortality among patients in intensive care units.

OBJECTIVE: To evaluate the role that nosocomial pneumonia plays in the outcome of intensive care unit (ICU) patients. DESIGN: Cohort study. SETTING: Medical ICU, Hôpital Bichat, Paris, France, an academic tertiary care center. PATIENTS: A total of 1978 consecutive patients admitted to the ICU for at least 48 hours. MAIN OUTCOME MEASURES: Various parameters known to be strongly associated with death of ICU patients were recorded: age, location before admission to the ICU, diagnostic categories, Acute Physiology and Chronic Health Evaluation (APACHE) II score, Simplified Acute Physiologic Score, McCabe score, number and type of dysfunctional organs, and the development of nosocomial bacteremia and nosocomial urinary tract infection. These variables and the presence or absence of nosocomial pneumonia were compared between survivors and nonsurvivors and entered into a stepwise logistic regression model to evaluate their independent prognostic roles. RESULTS: Nosocomial pneumonia developed in 328 patients (16.6%) whose mortality was 52.4% compared with 22.4% for patients without ICU-acquired pneumonia (P < .001), APACHE II score (odds ratio [OR] = 1.08; 95% confidence interval [CI], 1.06 to 1.10; P < .001), number of dysfunctional organs (OR = 1.54; 95% CI, 1.36 to 1.74; P < .001), nosocomial pneumonia (OR = 2.08; 95% CI, 1.55 to 2.80; P < .001), nosocomial bacteremia (OR = 2.51; 95% CI, 1.78 to 3.55; P < .001), ultimately or rapidly fatal underlying disease (OR = 1.76; 95% CI, 1.38 to 2.25; P < .001), and admission from another ICU (OR = 1.30; 95% CI, 1.01 to 1.68; P =.04) were significantly associated with mortality. CONCLUSION: These data suggest that, in addition to the severity of underlying medical conditions and nosocomial bacteremia, nosocomial pneumonia independently contributes to ICU patient mortality.

APACHE↗
PubMed1996

Closed drainage using Redon catheters for local treatment of poststernotomy mediastinitis.

BACKGROUND: Continuous irrigation has been used worldwide for the treatment of acute poststernotomy mediastinitis. However, its high rate of failure led to the development of new methods, among them closed drainage with Redon catheters. METHODS: We evaluated the results obtained with Redon catheters in 70 patients, and compared them to those obtained in 38 patients treated with continuous irrigation. RESULTS: The two treatment groups were not different for age, type of cardiac operation, and initial severity of illness. Local failure of Redon catheter drainage occurred less frequently (20 of 38 versus 9 of 70 patients; p = 0.0001). This reduced failure rate was mainly attributable to a lower incidence of superinfections (10 of 38 versus 2 of 70 patients; p = 0.0002), but also to a lower incidence of primary failure (10 of 38 versus 7 of 70 patients; p = 0.026). Mortality was significantly decreased (15 of 38 versus 12 of 70 patients; p = 0.01). The other major advantage of this technique was the simplicity of its use. CONCLUSIONS: The technique using Redon catheters should be considered an effective and convenient treatment of acute poststernotomy mediastinitis.

Acute Disease↗
PubMed1996

Long-term outcome and quality of life of patients requiring multidisciplinary intensive care unit admission after cardiac operations.

Patients with organ failure or severe infection after cardiac operations may require prolonged stays in the intensive care unit. This study examined long-term mortality and determined quality of life for surviving patients in this group. This observational cohort study was conducted at Bichat Hospital, Paris, an academic tertiary care center. The study group consisted of 116 consecutive patients who underwent cardiac operations and were transferred to the multidisciplinary intensive care unit between January 1986 and December 1987. Patients referred for mediastinitis were automatically excluded. Respiratory failure (88.8%) and hemodynamic instability (81.9%) were the main causes of transfer; an infection was present in 23.3% of patients at entry into the intensive care unit. Twenty-seven patients (23.3%) died in the intensive care unit. Presurgical New York Heart Association functional class, postoperative bacteremia before admission to the intensive care unit, and severity of illness on admission to the intensive care unit were independent predictors of death in the intensive care unit. After an average follow-up of 81 months (range 70 to 93 months), 69% of the patients alive at transfer from the intensive care unit were still alive. Preoperative New York Heart Association functional class was the only long-term independent prognostic factor. Quality of life, as evaluated by the Nottingham Health Profile, was good for more than 70% of the survivors and was not influenced by any recorded variables, with the exception of age.

Aged↗
PubMed1996

Mortality due to ventilator-associated pneumonia or colonization with Pseudomonas or Acinetobacter species: assessment by quantitative culture of samples obtained by a protected specimen brush.

Ventilator-associated pneumonia (VAP) due to multiresistant pathogens is associated with a high death rate. We analyzed the relationship between VAP due to Pseudomonas or Acinetobacter species and death by comparing the outcomes for patients colonized with these pathogens (bacterial counts of < 10(3) cfu/mL) with those for patients with pneumonia due to these pathogens (bacterial counts of > or = 10(3) cfu/mL). Samples were obtained systematically with a protected specimen brush when pneumonia was suspected. Clinical characteristics at admission to our intensive care unit and clinical features at the time of suspicion of VAP were not significantly different between colonized patients and those with VAP. Mortality rates were 29% among colonized patients and 73% among patients with VAP (P < .001). These results demonstrate a relationship between a high mortality rate and the development of pneumonia due to multiresistant, nonfermenting, gram-negative bacilli ( > or = 10(3) cfu/mL) in the lower airways of patients receiving ventilatory support.

Acinetobacter↗
PubMed1996

Interactions between neutrophils and cytokines in blood and alveolar spaces during ARDS.

Although the pathogenesis of the acute respiratory distress syndrome (ARDS) is complex and poorly understood, several observations point to an important role of interactions between polymorphonuclear neutrophils (PMN) and cytokines in this process. We therefore studied certain parameters involved in PMN transendothelial migration (adhesion molecule expression and cytoskeletal organization) in patients with ARDS (n = 14) in comparison with other ventilated patients (n = 15). We found that in the basal state, both whole-blood PMN and alveolar PMN obtained by bronchoalveolar lavage (BAL) were activated, as shown by decreased L-selectin CD62L and increased beta 2 integrin CD11b expression, as well as decreased F-actin content. The degree of PMN activation increased with the degree of lung injury and with the levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and interleukin-8 (IL-8). Moreover, the capacity of ex vivo stimulation of alveolar PMN by a bacterial peptide was low in ARDS and could partly account for the high susceptibility of these patients to lung infection. Therefore, ARDS-associated lung injury could be caused, at least in part, by inappropriate adhesion and transendothelial migration of proinflammatory cytokine-primed PMN.

APACHE↗
PubMed1996

Diagnosis of pulmonary infections in mechanically ventilated patients.

The optimal management strategy for ventilator-dependent patients who develop symptoms suggestive of lung infection remains controversial. Proponents of the empirical approach prefer to treat most patients with fever and pulmonary infiltrates with one or more new antibiotics, even if it may be difficult (1) to determine whether pneumonia has developed in such patients, (2) in case of infection, to precisely identify the responsible microorganisms and thereby select the optimal antimicrobial treatment, and (3) to avoid resorting to broad-spectrum drug coverage in patients without true infection. Our personal bias is that using bronchoscopic techniques to obtain protected specimen brush and bronchoalveolar lavage specimens from the affected area in the lung permits to devise a therapeutic strategy superior to the one based only on clinical evaluation. These bronchoscopic techniques, when they are performed before new antibiotics are administered, enable physicians to identify most patients who need immediate treatment and select optimal therapy, in a manner that is safe and well tolerated by patients. Furthermore, they frequently permit the clinician to withhold antimicrobial treatment in patients without infection, minimizing the risk of the emergence of resistant microorganisms in the intensive care unit. In patients with clinical evidence of severe sepsis, the initiation of antibiotic therapy should not, however, be delayed while awaiting bronchoscopy, and patients should be given immediate treatment with antibiotics. In that case, "simplified" non-bronchoscopic diagnostic procedures might allow obtaining reliable distal pulmonary secretions for quantitative cultures on a 24-hour basis just before the initiation of a new antimicrobial therapy.

Bacterial Infections↗
PubMed1996

Severe exacerbations of COPD patients: the role of pulmonary infections.

Infection is usually considered the main cause of acute exacerbation in chronic obstructive pulmonary disease (COPD). However, uncertainty persists concerning the exact role of bacterial and viral infection in this setting because of the confusing and conflicting data on the role of tracheobronchial microflora and the usefulness of antibiotics in treating this disease. Most COPD patients have evidence of lower respiratory tract chronic bacterial colonization during remission periods as well as during acute exacerbations. This is evidenced by using microbiological analysis of secretions, which reflect all the respiratory tract (sputum), the lower respiratory tract (transtracheal aspiration), or the distal respiratory tract (protected specimen brush). Potentially pathogenic organisms can be recovered from the respiratory tract secretions of virtually all patients with COPD at some time during the course of their disease. Absence of difference in isolation of potentially pathogenic organisms between remission periods and acute exacerbations suggests that bacterial infection is probably not the predominant cause of acute exacerbations in COPD. In contrast, data indicate that the association between viral infections and acute exacerbations is clearer than that with bacteria, affecting probably more than 20% of cases. The role of antibiotic therapy in acute exacerbations of COPD remains controversial. (1) Clearly, antibiotic therapy is urgently required in COPD patients with pneumonia. (2) Review of the conflicting results of studies evaluating the role of antibiotic therapy for preventing acute exacerbations suggests that there is no clear-cut rationale for prophylactic treatment of infection for all patients with COPD; it seems, however, that such treatment may be of some use in highly selected patients, such as those with many exacerbations in the winter. (3) Similarly, data are conflicting concerning the curative use of antibiotic therapy, with some studies suggesting acceleration of recovery, prevention of acute deterioration, and longer period of freedom from recurrent exacerbations; conversely many patients recover from exacerbations without resorting to an antibiotic. Unfortunately, no clear data identify patients who could benefit from antibiotic treatment, probably justifying most clinicians' choice to treat acute exacerbations as infectious events.

Acute Disease↗
PubMed1995

Diagnosis and treatment of nosocomial pneumonia in patients in intensive care units.

The optimal management strategy for ventilator-dependent patients who develop symptoms suggestive of lung infection remains controversial. Our personal bias is that using bronchoscopic techniques to obtain protected-brush and bronchoalveolar lavage specimens from the affected area in the lung permits physicians to devise a therapeutic strategy that is superior to one based only on clinical evaluation. These bronchoscopic techniques, when they are performed before new antibiotics are administered, enable physicians to identify most patients who need immediate treatment and to select optimal therapy, in a form that is safe and well tolerated by patients. Furthermore, they frequently permit physicians to withhold antimicrobial treatment from patients without infection, thereby minimizing the risk of emergence of resistant microorganisms in the intensive care unit. Despite many advances in antimicrobial therapy, successful treatment of patients with nosocomial pneumonia remains a complex undertaking, and ultimately further trials will be needed to clarify the optimal duration of treatment and the circumstances in which monotherapy can be safely used.

Aminoglycosides↗
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

Nosocomial pneumonia in ventilated patients: a cohort study evaluating attributable mortality and hospital stay.

PURPOSE: Although nosocomial pneumonia is a common problem in intubated and ventilated patients, previous studies have not clearly demonstrated that nosocomial pneumonia actually results in increased mortality or prolongs hospitalization of these patients. In an attempt to answer these questions, we have performed a cohort study in which patients who developed nosocomial pneumonia and control subjects were carefully matched for the severity of underlying illness and other important variables. PATIENTS AND METHODS: Case patients were 48 ventilated patients with nosocomial pneumonia identified on the basis of results of protected specimen brush quantitative culture and identification of intracellular organisms in cells recovered by bronchoalveolar lavage. For matching cases and their respective controls, the following variables were used: age (+/- 5 years), Simplified Acute Physiologic Score (+/- 3 points), indication for ventilatory support, date of admission, and duration of exposure to risk. RESULTS: Successful matching was achieved for 222 of 240 (92.5%) variables. The mortality rate in cases was 26 of 48 (54.2%) compared with 13 of 48 (27.1%) in controls. The attributable mortality was 27.1% (95% confidence interval [CI], 8.3% to 45.9%; p < 0.01) and the risk ratio for death was 2.0 (95% CI, 1.61 to 2.49). The mean length of stay was 34 days for cases and 21 days for controls (p < 0.02). In the case of pneumonia due to Pseudomonas or Acinetobacter species, the mortality rate was 71.4%, the attributable mortality was 42.8% (95% CI, 14.5% to 69.0%), and the risk ratio was 2.50 (95% CI, 1.31 to 4.61). CONCLUSION: Pneumonias occurring in ventilated patients, especially those due to Pseudomonas or Acinetobacter species, are associated with considerable mortality in excess of that resulting from the underlying disease alone, and significantly prolong the length of stay in the intensive care unit.

Acinetobacter Infections↗
PubMed1993

Analysis of vancomycin entry into pulmonary lining fluid by bronchoalveolar lavage in critically ill patients.

Vancomycin penetration into the fluid lining the epithelial surface of the lower respiratory tract was studied by performing fiberoptic bronchoscopy with bronchoalveolar lavage on 14 critically ill, ventilated patients who had received the drug for at least 5 days. The apparent volume of epithelial lining fluid (ELF) recovered by bronchoalveolar lavage was determined by using urea as an endogenous marker. Vancomycin levels in ELF ranged from 0.4 to 8.1 micrograms/ml (mean, 4.5 micrograms/ml), while the mean simultaneous level of the drug in plasma was 24 micrograms/ml (range, 9 to 37.4 micrograms/ml). There was a significant relationship (r = 0.64, P < 0.02) between vancomycin levels in plasma and those in ELF, with a correlation whose slope (0.15) indicated that the blood-to-ELF ratio of drug penetration was 6:1. Using the albumin concentration in ELF as a marker of lung inflammation, we found that vancomycin penetration was higher in patients with ELF albumin values of > or = 3.4 mg/ml than in patients with normal values (< 3.4 mg/ml) (P < 0.02). These results suggest that the vancomycin distribution includes the ELF of the lower respiratory tract at a concentration that is dependent upon the levels in blood and the alveolar capillary membrane protein permeability. These concentrations were well above the MICs for most staphylococci and enterococci.

Aged↗