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S Chevret

Publications and source records attributed to S Chevret.

At least 163 records · Page 9Linked to original sources
PubMed1994

Chronic diffuse infiltrative lung disease: determination of the diagnostic value of clinical data, chest radiography, and CT and Bayesian analysis.

PURPOSE: To assess the value of clinical, chest radiographic, and computed tomographic (CT) findings in classifying chronic diffuse infiltrative lung disease (CDILD) MATERIALS AND METHODS: Two samples from the same population were consecutively studied: the training set (group A, n = 208) for the development of the decision aid and the test set (group B, n = 100) for validation. Computer-aided diagnoses were made with a Bayesian model that assigned to each patient diagnostic probabilities based on clinical, radiographic, or CT variables. RESULTS: In group A, a correct diagnosis based on clinical data was obtained in 29% of cases; radiography, 9%; and CT, 36%. This increased to 54% when clinical and radiographic variables were combined (P < .0001) and to 80% when data from all three were analyzed together (P < .0001). With prior and conditional probabilities determined from group A, the frequency of correct diagnosis in group B was 27% with clinical data, which increased to 53% (P < .0001) with radiographic findings and 61% after including CT data (P = .07). CONCLUSION: CT can help determine the specific diagnosis in patients with CDILD.

Bayes Theorem↗
PubMed1994

Severe community-acquired pneumonia. Etiology, epidemiology, and prognosis factors. French Study Group for Community-Acquired Pneumonia in the Intensive Care Unit.

A prospective study of 132 patients with severe community-acquired pneumonia (CAP) treated in the ICU was carried out to determine the causative agents, the value of the clinical, biological, and radiologic features in predicting the etiology, and to define prognostic factors. The study group included 98 men and 34 women (mean age: 58 +/- 18 years). The most frequent underlying condition was COPD (51 patients, 39 percent). On admission, 35 patients were in shock, 71 were mentally confused, and 81 (61 percent) required mechanical ventilation during their hospitalization. The clinical, laboratory, and radiologic parameters were of little value for predicting the etiology in patients with severe CAP. An etiologic diagnosis was made in 95 (72 percent) patients. The most frequent pathogens were Streptococcus pneumoniae (43 cases [45 percent]), Gram-negative bacilli (14 cases [15 percent]), and Haemophilus influenzae (14 cases [15 percent]) Mortality was 24 percent. It was significantly associated with a age more than 60 years, septic shock, impairment of alertness, mechanical ventilation requirement, bacteremic pneumonia, and S pneumoniae or Enterobacteriaceae as the causes of the pneumonia. Recommendations for antibiotic chemotherapy in patients with severe CAP admitted to the ICU are included.

Community-Acquired Infections↗
PubMed1994

Prognostic value of early computed tomographic scans in severe acute pancreatitis. French Association for Surgical Research.

BACKGROUND: The prognostic value of computed tomographic (CT) scans in differentiating mild from severe forms of acute pancreatitis is well established. Nonetheless, in patients with a severe form of the disease, some will have a relatively uneventful course while others will have severe complications. This prospective, multicenter study was done to evaluate the prognostic value of early CT scan in a homogenous group of patients with a first attack of severe acute pancreatitis. STUDY DESIGN: Dynamic CT scans were performed within 48 hours after admission. A standardized form was completed for each CT scan, recording the following data: abnormal enhancement of the pancreas itself, characteristics of extrapancreatic collections, and visualization of the portal and splenic veins. Statistical analysis was based on the log rank test and Cox's model and used death and abscess occurrence as the two end points. RESULTS: Two hundred twenty-eight patients from 46 centers were included in the study. The median Ranson and Imrie scores were 3 and 4, respectively. Forty-seven patients died and 72 had an abscess. The CT scan findings indicating an increase in mortality rate were nonenhancement of the neck of the pancreas (p = 0.04) and extrapancreatic collections within the left (p = 0.001) and right (p = 0.02) pararenal posterior spaces. The risk of abscess increased when there was nonvisualization of the splenic vein (p = 0.0001), in the presence of extrapancreatic collections in the right pararenal posterior space (p = 0.03) and when the extrapancreatic collections were heterogenous (p = 0.003). CONCLUSIONS: This study demonstrated that the location of extrapancreatic collections and nonvisualization of the splenic and portal veins on CT scans were not previously recognized prognostic factors of complicated outcome in patients with severe acute pancreatitis.

Abdominal Abscess↗
PubMed1993

High-dose chemoradiotherapy and autologous blood stem cell transplantation in multiple myeloma: results of a phase II trial involving 63 patients.

Sixty-three patients with high tumor mass multiple myeloma were treated with high-dose chemotherapy and total body irradiation supported by autologous blood stem cell transplantation. After high-dose therapy, they were monitored for a median of 44 months. Seven patients died early from toxicity. All the other patients, including those whose disease was resistant to previous therapies, showed a tumor mass reduction. At 6 months postengraftment, 40 (71%) of the surviving patients had minimal residual disease and 11 (20%) were in apparent complete remission. During follow-up, 25 out of the 63 (39%) patients relapsed and 16 of these died; 31 (49%) had a sustained remission. The median overall and event-free survival times after transplantation were 59 and 43 months, respectively. The initial serum beta 2-microglobulin value (> or < 2.8 mg/L) and length of previous therapy (> or < 6 courses of chemotherapy) were the only significant prognostic factors. In all surviving patients, blood stem cell autograft provided satisfactory and sustained haematopoietic reconstitution most often within 15 days. High dose chemoradiotherapy followed by autologous blood stem cell transplantation is thus an important therapeutic option for young patients with aggressive multiple myeloma.

Adult↗
PubMed1993

Splenectomy is safe and effective in human immunodeficiency virus-related immune thrombocytopenia.

Sixty-eight patients, followed in a prospective cohort study of 185 human immunodeficiency virus (HIV)-infected patients with severe immune thrombocytopenia (platelets < 50 x 10(9)/L), underwent splenectomy, 2 to 41 months (median: 10 months) after immune thrombocytopenic purpura (ITP) was diagnosed. The mean platelet count increased from 18 x 10(9)/L to 223 x 10(9)/L with a persistent increase in 56 (82%). It also led to a significant increase of the mean CD4 cell count from 475 x 10(6)/L to 725 x 10(6)/L within a mean delay of 10 months. In the whole cohort, with a mean follow-up of 63 months (range, 6 to 126), the 5-year estimated rate for progression to acquired immunodeficiency syndrome (AIDS) was 23% (95% confidence interval [CI], 15% to 31%) and the AIDS-free survival was 69% (95% CI, 61% to 77%). To investigate the potential impact of splenectomy, a Cox's multiple regression model was used; as splenectomy was not randomly assigned, it was incorporated as a time-dependent covariate. After adjustment on the CD4 cell count, no statistically significant differences were observed between the splenectomized and the nonsplenectomized patients: AIDS progression rate (P = 0.23), survival (P = 0.64) and AIDS-free survival (P = 0.72) were not influenced by splenectomy. Splenectomy is both effective and safe in the treatment of severe, refractory ITP associated with HIV infection.

Female↗
PubMed1993

The continual reassessment method in cancer phase I clinical trials: a simulation study.

In cancer studies, the aim of phase I clinical trials is to identify an appropriate dose for experimentation in phase II and III studies. The continual reassessment method (CRM) has been developed recently and presented as the method of choice in the design and analysis of such phase I studies. However, to implement the method, some methodological and practical considerations must be addressed. This paper examines, through a simulation study, the sensitivity of CRM both to the initial modelling of the dose-toxicity relationship and the prior. It appears that the performance of CRM can be improved by using vague priors and initial tuning of the model to allow flexibility.

Antineoplastic Agents↗
PubMed1993

Incidence and risk factors of pneumonia acquired in intensive care units. Results from a multicenter prospective study on 996 patients. European Cooperative Group on Nosocomial Pneumonia.

OBJECTIVE: To estimate the incidence of pneumonia acquired in the intensive care unit (ICU), and to define risk factors for developing such an event. DESIGN: European prospective survey, in which all patients admitted to the participating ICU from January, 17 to 23, 1990, were followed until ICU discharge. SETTING: 107 general ICUs from 18 countries. PATIENTS: Of 1078 admitted to the ICUs, 996 patients without pneumonia at admission were studied. MEASUREMENTS: Pneumonia was diagnosed by the staff physician on the basis of clinical, radiological and microbiological criteria, secondly validated by an expert committee who reviewed all the forms and even recontacted ICU physicians. Crude incidence and time to occurrence of pneumonia were estimated, then both used as end-points for prognosis analysis. RESULTS: 89 pneumoniae were observed: crude incidence was estimated at 8.9% 7-day and 14-day pneumonia rates at 15.8% and 23.4%, respectively. The risk of developing pneumonia increased when either coma, trauma, respiratory support, Apache II > 16 and/or imparied air-way reflexes were present at ICU admission. To predict time to occurrence of pneumonia, only two variables remained significant: the presence of impaired airway reflexes at admission and the use of mechanical ventilation during ICU course. CONCLUSIONS: The role of the injury to the respiratory system-with the subsequent need for respiratory support--appears central in determining the risk to acquire pneumonia in ICU. In the future, the predictive value of severity scores during ICU course should be otherwise assessed.

Adult↗
PubMed1993

Iatrogenic complications in adult intensive care units: a prospective two-center study.

OBJECTIVES: a) To evaluate the frequency, types, severity, and morbidity of iatrogenic complications; b) determine associated factors that favor iatrogenic complications; and c) suggest new or more efficient protective measures that may be taken to improve patient safety. DESIGN: Prospective, observational study. SETTING: Two ICUs in France. PATIENTS AND METHODS: The study included 382 patients (age > or = 15 yrs; 400 consecutive admissions). Patients were monitored by two physicians in each ICU to assess all iatrogenic complications occurring during their ICU stay, with the exception of adverse effects of drugs. An iatrogenic complication was defined as an adverse event that was independent of the patient's underlying disease. RESULTS: We observed 316 iatrogenic complications in 124 (31%) of the 400 admissions. Of these iatrogenic complications, 107 (in 53 [13%] of the 400 admissions) complications were major, three leading to death. Severe hypotension, respiratory distress, pneumothorax, and cardiac arrest represented 78% of the major iatrogenic complications. Fifty-nine percent of the major iatrogenic complications had clearly identified associated factors. Human errors accounted for 67% of these factors. Patients > 65 yrs (adjusted odds ratio = 2.6, 95% confidence interval: 1.4 to 4.9) and those patients admitted with two or more organ failures (adjusted odds ratio = 4.8, 95% confidence interval: 2.5 to 9.2) were more likely to develop major iatrogenic complications. High or excessive nursing workload also led to an increased risk of major iatrogenic complications. Persistent morbidity, secondary to iatrogenic complications at the time of discharge, was present in five survivors. The risk of ICU death was about two-fold higher for the patients with major iatrogenic complications than in the remaining patients after adjusting for the Organ System Failure Score and the prognosis of the disease (relative risk = 1.92, 95% confidence interval: 1.28 to 2.56). CONCLUSIONS: Major iatrogenic complications were frequent, associated with increased morbidity and mortality rates, related to high or excessive nursing workload, and were often secondary to human errors. To improve patient safety in our ICUs, preventive measures should be targeted primarily on the elderly and the most severely ill patients. Special attention should be given to improving the organization of workload and training, and promoting wider use of noninvasive monitoring.

Adult↗
PubMed1993

Plasma exchange morbidity in Guillain-Barré syndrome: results from the French prospective, randomized, multicenter study. The French Cooperative Group.

OBJECTIVES: To describe all adverse events occurring during plasma exchange sessions in adult patients with the Guillain-Barré syndrome. To analyze these events with regard to the technical modalities and biological changes induced by sessions, and to try to identify a population at high risk for adverse events. DESIGN: Double-blind, randomized, prospective, multicenter trial. SETTING: A total of 28 French and Swiss intensive care units. PATIENTS: The study is based on 220 patients allocated either to plasma exchange (n = 109) or not (n = 111). This study focused on 105 patients who received at least one plasma exchange, with replacement fluid secondly allocated by randomization to albumin, or fresh frozen plasma. A total of 105 patients underwent 390 plasma exchanges. Fifty-five patients received albumin (208 sessions) as replacement fluid, and 50 patients received fresh frozen plasma (182 sessions). INTERVENTIONS: Prospective monitoring of patients for each session including technical modalities, adverse effects, and biological parameters. MEASUREMENTS AND MAIN RESULTS: A total of 253 adverse incidents were recorded. At least one adverse incident occurred in 39% of plasma exchange sessions among 80 (76%) patients. In 15 patients, plasma exchange treatment had to be discontinued because of severe intolerance (six patients, including three patients with severe bradycardias), intercurrent complications, mainly infections (four patients), and technical difficulties. One patient with pneumococcal septicemia and pneumonia died during the second plasma exchange session. Fresh frozen plasma was associated with more adverse incidents than albumin (135 vs. 118, p = .008). The occurrence of adverse events was also related to the preplasma exchange hemoglobin level assessed before the session (p = .04). Otherwise, the frequency of adverse effects did not depend on technical modalities (type of equipment, anticoagulation). Age, sex, previous history, neurologic severity, and the need for mechanical ventilation, as assessed on inclusion in the study, did not modify the risk of adverse effects. Finally, occurrence of bradycardia did not rely on initial neurologic severity. CONCLUSIONS: These results confirm that fresh frozen plasma should be abandoned as replacement fluid in plasma exchanges of Guillain-Barré syndrome patients. They also underline the need for close monitoring of patients during sessions and, especially, the respect of treatment contraindications. Some adverse incidents could be attributed to the underlying disease rather than to the plasma exchange session.

Albumins↗
PubMed1993

Influence of long-term oro- or nasotracheal intubation on nosocomial maxillary sinusitis and pneumonia: results of a prospective, randomized, clinical trial.

OBJECTIVE: To compare the occurrence rate of nosocomial maxillary sinusitis and pneumonia in patients who have undergone nasotracheal vs. orotracheal intubation. DESIGN: Randomized, clinical trial. SETTING: General adult intensive care unit (ICU) in a nonteaching public hospital. PATIENTS: A total of 300 (209 male, 91 female) patients were included. The mean age was 59 +/- 17 (SD) yrs. The simplified acute physiologic score was 14 +/- 6. Reasons for admission to the ICU were: coma (n = 78), pneumonia (n = 46), infection (n = 35), surgery (n = 34), multiple trauma (n = 20), head trauma (n = 12), other (n = 75). Among the 300 patients, 149 were randomized into the nasotracheal group and 151 into the orotracheal group. No statistical difference was found between initial characteristics of the two groups. INTERVENTIONS: Patients were randomized between nasal and oral endotracheal intubation. Gastric intubation was performed via the same route as endotracheal intubation. Sinus computed tomography (CT) scans were performed every 7 days or earlier in case of fever and/or purulent nasal discharge. Criteria for nosocomial sinusitis were as follows: fever of > 38 degrees C, radiographic (sinusal air-fluid level or opacification on CT scan) signs and presence of purulent aspirate from the involved sinus puncture with 10(3) colony-forming units (cfu)/mL. Diagnosis of pneumonia was based on classical criteria and a protected brush specimen with 10(3) cfu/mL. MEASUREMENTS AND MAIN RESULTS: Radiographic evidence of sinusitis was observed in 78 patients, 45 from the nasal group and 33 from the oral group (p = .08, log-rank test). Among these patients, 54 fulfilled the sinusitis criteria stated above, 29 in the nasal group and 25 in the oral group (p = .75, log-rank test). Nosocomial pneumonia was observed in 26 patients, 17 in the nasal group and 9 in the oral group (p = .11, log-rank test). A multivariable analysis considering sinusitis as a time-dependent factor has suggested that sinusitis increased the risk of nosocomial pneumonia by a factor of 3.8. Nosocomial septicemia was observed in 33 patients, 22 episodes in the nasal group and 13 episodes in the oral group (p = .11, log-rank test). Overall mortality rate was 37% in the nasal group vs. 41% in the oral group (p = .37, log-rank test). Episodes of atelectasis and accidental extubations, and doses of sedative drugs and antibiotics were not different between the two groups. Length of mechanical ventilation did not differ between the two intubation groups. The mean length of stay in the ICU was 11 +/- 15 days in the nasal group vs. 9.5 +/- 11 days in the oral group (p = .27, Student's t-test). CONCLUSIONS: In patients undergoing prolonged mechanical ventilation, there was no statistically significant difference in the occurrence rate of nosocomial sinusitis or pneumonia between patients undergoing tracheal intubation via the nasal vs. oral route. A trend (p = 0.008) suggests less sinusitis in the orotracheal group.

Adult↗
PubMed1993

[Immunoglobulins or plasma exchange? Guillain-Barré syndrome: indications for plasma exchange and immunoglobulins].

The effect of plasma exchange (PE) in the Guillain-Barré syndrome (GBS) has been evaluated in 4 randomized clinical trials. A positive effect could be excluded in only one study conducted in Great Britain which included 29 patients. The more powerful studies conducted in Sweden (39 patients), in North America (245 patients) and in France (220 patients) demonstrated that early use of four PEs in patients with a GBS severe enough to require assistance in walking was followed by decreased duration and severity of the acute phase. These conclusions were ratified at a North American consensus conference. More recently, PE has been demonstrated to increase the number of patients who recover normal muscular power after a 1-year follow-up. The French trial also demonstrated that diluted albumin should be preferred over fresh frozen plasma. The number of plasma exchanges and the role of PE in initially benign forms is of great importance and is now under study by a cooperative group in France. The effect of immunoglobulins (IgG) was recently investigated in a randomized trial including 150 patients. In this study, high doses (0.4 g/kg/day for 5 days) were compared with 5 PE administered between days 7 and 14 in children and adults who, at inclusion, were unable to walk. The main result was that the outcome at one month was good with IgG as with PE. Treatment is easier with IgG, and morbidity is lower. Direct costs are similar. If IgG are shown to be as effective as PE, IgG should be given for GBS.(ABSTRACT TRUNCATED AT 250 WORDS)

Contraindications↗
PubMed1992

A controlled trial in intensive care units of selective decontamination of the digestive tract with nonabsorbable antibiotics. The French Study Group on Selective Decontamination of the Digestive Tract.

BACKGROUND: Selective decontamination of the digestive tract with topical nonabsorbable antibiotics has been reported to prevent nosocomial infections in patients receiving mechanical ventilation, and the procedure is used widely in Europe. However, it is unclear whether selective decontamination improves survival. METHODS: We conducted a randomized, double-blind multicenter study in which 445 patients receiving mechanical ventilation in 15 intensive care units were given either prophylactic nonabsorbable antibiotics (n = 220) or a placebo (n = 225). Topical antibiotics (tobramycin, colistin sulfate, and amphotericin B) or a placebo was administered through a nasogastric tube and applied to the oropharynx throughout the period of ventilation. The main end points were the mortality rate in the intensive care unit and within 60 days of randomization. RESULTS: A total of 142 patients died in the intensive care unit; 75 (34 percent) in the treatment group and 67 (30 percent) in the placebo group (P = 0.37). Mortality within 60 days of randomization was similar in the two groups (P = 0.40), even after adjustment for factors that were either unbalanced or individually predictive of survival in the two groups (P = 0.70). Pneumonia developed in 59 patients (13 percent) in the intensive care unit within 30 days of enrollment in the study (33 in the placebo group and 26 in the treatment group, P = 0.42). Pneumonia acquired in the intensive care unit and due to gram-negative bacilli was less frequent (P = 0.01) in the treatment group than in the placebo group. The total charges for antibiotics were 2.2 times higher in the treatment group. CONCLUSIONS: Selective decontamination of the digestive tract does not improve survival among patients receiving mechanical ventilation in the intensive care unit, although it substantially increases the cost of their care.

Administration, Topical↗
PubMed1992

Breathing disorders during sleep in myasthenia gravis.

Twenty consecutive patients (16 women and 4 men), with a mean age of 40 years, who were diagnosed and treated for myasthenia gravis were enrolled in a prospective investigation aimed at determining the amount of respiratory disturbance occurring during sleep while they received treatment. Patients were clinically evaluated to determine body mass index, presence of upper airway anatomical abnormalities, level of functional capacity and activity scored from 1 to 5, and presence of sleep-related complaints. They underwent daytime pulmonary function tests, determination of maximal static inspiratory pressure, measurement of transdiaphragmatic pressure, and measurement of arterial blood gas levels. Polygraphic monitoring during sleep, evaluating respiration and oxygen saturation, was also performed. Results indicated that in the studied population, all subjects had evidence of daytime diaphragmatic weakness as demonstrated by transdiaphragmatic pressure measurements, independent of the degree of autonomy and functional capacity and activity level reached. Older patients with moderately increased body mass index, abnormal total lung capacity, and abnormal daytime blood gas concentrations were the primary candidates for development of diaphragmatic sleep apneas and hypopneas, and oxygen desaturation of less than 90% during sleep. However, these clear indicators were not found in all subjects with sleep-related disordered breathing. Rapid-eye-movement sleep was the time of highest breathing vulnerability during sleep. Sleep-related complaints may also help identify subjects at risk for abnormal breathing during sleep, even when daytime functional activity is judged normal.

Adult↗
PubMed1992

Single- versus triple-lumen central catheter-related sepsis: a prospective randomized study in a critically ill population.

PURPOSE: A prospective randomized study was conducted over a 23-month period in an adult medical-surgical intensive care unit to determine whether triple-lumen catheters reduce the need for peripheral vascular access and whether they are associated with a higher rate of infection than single-lumen catheters. PATIENTS AND METHODS: After the insertion route, internal jugular or subclavian, was selected by the physician, patients were randomized either to single-lumen or triple-lumen catheter groups. Complementary peripheral vascular access was allowed in both groups. Catheters were removed according to preestablished defined reasons: suspicion of catheter-related sepsis, uselessness of central venous access, duration of catheterization of more than 21 days, discharge from the intensive care unit, or death. RESULTS: Data on 129 central venous catheters were collected from 91 consecutive patients. Twenty-five of 68 patients from the single-lumen group and 1 of 61 patients from the triple-lumen group needed peripheral vascular access (p less than 0.001). Catheter-related sepsis rates, defined either by clinical signs and positive qualitative tip cultures (8.9% versus 11.5%) or by quantitative tip cultures (16.2% versus 11.5%), were identical in the single-lumen and triple-lumen groups (type II error: 8%). CONCLUSION: In intensive care units, the use of triple-lumen catheters is associated with a dramatic decrease in the need for peripheral vascular access. The incidence of central venous catheter-related sepsis appears identical for single- and triple-lumen catheters.

Adult↗
PubMed1992

Is the internal mammary artery an acceptable graft in the elderly patients with left main coronary artery disease?

Age over 70 years and critical stenosis of the left main coronary artery trunk are two situations in which the use of the internal mammary artery has been questioned. Because the coexistence of these two conditions is increasingly seen, we reviewed our experience with 53 patients 70 years of age or older that underwent myocardial revascularization for left main disease. In 17 patients, the left anterior descending coronary artery was grafted with the left internal mammary artery whereas the 36 remaining patients were exclusively revascularized by means of saphenous vein conduits. There was no significant difference in postoperative mortality or morbidity between the two patient groups. We conclude that elderly patients with left main disease should be offered the benefits of a mammary artery graft provided they are hemodynamically stable.

Age Factors↗