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Jean-Pierre Auffray

Publications and source records attributed to Jean-Pierre Auffray.

16 recordsLinked to original sources

Protective ventilation influences systemic inflammation after esophagectomy: a randomized controlled study.

BACKGROUND: Esophagectomy induces a systemic inflammatory response whose extent has been recognized as a predictive factor of postoperative respiratory morbidity. The aim of this study was to determine the effectiveness of a protective ventilatory strategy to reduce systemic inflammation in patients undergoing esophagectomy. METHODS: The authors prospectively investigated 52 patients undergoing planned esophagectomy for cancer. Patients were randomly assigned to a conventional ventilation strategy (n = 26; tidal volume of 9 ml/kg during two-lung and one-lung ventilation; no positive end-expiratory pressure) or a protective ventilation strategy (n = 26; tidal volume of 9 ml/kg during two-lung ventilation, reduced to 5 ml/kg during one-lung ventilation; positive end-expiratory pressure 5 cm H2O throughout the operative time). RESULTS: Plasmatic levels of interleukin (IL)-1beta, IL-6, IL-8, and tumor necrosis factor alpha were measured perioperatively and postoperatively. Pulmonary function and postoperative evolution were also evaluated. Patients who received protective strategy had lower blood levels of IL-1beta, IL-6, and IL-8 at the end of one-lung ventilation (0.24 [0.15-0.40] vs. 0.56 [0.38-0.89] pg/ml, P < 0.001; 91 [61-117] vs. 189 [127-294] pg/ml, P < 0.001; and 30 [22-45] vs. 49 [29-69] pg/ml, P < 0.05, respectively) and 18 h postoperatively (0.18 [0.13-0.30] vs. 0.43 [0.34-0.54] pg/ml, P < 0.001; 54 [36-89] vs. 116 [78-208] pg/ml, P < 0.001; 16 [11-24] vs. 35 [28-53] pg/ml, P < 0.001, respectively). Protective strategy resulted in higher oxygen partial pressure to inspired oxygen fraction ratio during one-lung ventilation and 1 h postoperatively and in a reduction of postoperative mechanical ventilation duration (115 +/- 38 vs. 171 +/- 57 min, P < 0.001). CONCLUSION: A protective ventilatory strategy decreases the proinflammatory systemic response after esophagectomy, improves lung function, and results in earlier extubation.

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Inhaled nitric oxide does not prevent pulmonary edema after lung transplantation measured by lung water content: a randomized clinical study.

STUDY OBJECTIVE: In order to assess the effects of inhaled nitric oxide (iNO) in preventing early-onset lung edema from occurring after lung transplantation, we measured extravascular lung water (EVLW) in a group of lung transplant recipients who were at high risk for developing ischemia-reperfusion-induced lung injury. DESIGN: Prospective, randomized study. SETTINGS: Surgical ICU in a teaching hospital. PATIENTS: Thirty double-lung transplant recipients. INTERVENTIONS: Patients were randomized to receive or not receive 20 ppm iNO at the time of reperfusion (ie, before any occurrence of lung edema). In the NO group, iNO was then administered for a 12-h period. A double-dilution technique was used for the serial assessment of EVLW, intrathoracic blood volume, and cardiac index. Standard hemodynamic and pulmonary parameters were also recorded during the first 3 postoperative days. MEASUREMENTS AND RESULTS: Patients who received iNO did not have a different lung water content compared to control subjects (p = 0.61 [by analysis of variance (ANOVA)]). Blood oxygenation (ie, Pao(2)/fraction of inspired oxygen [Fio(2)] ratio) did not differ between the two groups (p = 0.61 [by ANOVA]). In both groups, EVLW and Pao(2)/Fio(2) ratio dropped significantly over time, regardless of the use of iNO (p < 0.01 [by ANOVA]). CONCLUSIONS: In the population studied, prophylactic iNO that was administered at 20 ppm had no effect on pulmonary edema formation and resolution following lung transplantation.

Administration, Inhalation↗

Ameba-associated microorganisms and diagnosis of nosocomial pneumonia.

To elucidate the role of ameba-associated microorganisms (AAMs) as etiologic agents of pneumonia, we screened for Legionella spp., Parachlamydia acanthamoeba, Afipia sp., Bosea spp., Bradyrhizobium spp., Mesorhizobium amorphae, Rasbo bacterium, Azorhizobium caulinodans, Acanthamoeba polyphaga mimivirus, and conventional microorganisms in 210 pneumonia patients in intensive-care units by using culture, polymerase chain reaction, and serologic testing. These resulted in 59 diagnoses in 40 patients. AAMs and non-AAMs were implicated in 10.5% of the patients. The infectious agents were identified in 15 patients: Acanthamoeba polyphaga mimivirus, 8; Legionella pneumophila, 3; L. anisa, 1; Parachlamydia sp., 1; Bosea massiliensis, L. worsleiensis, L. quinlivanii, and L. rubrilucens, 1; and M. amorphae and R. bacterium, 1. A. polyphaga mimivirus was the fourth most common etiologic agent, with a higher seroprevalence than noted in healthy controls. This finding suggested its clinical relevance. Therefore, AAM might cause nosocomial pneumonia and should be suspected when conventional microbiologic results are negative.

Acanthamoeba↗

Influence of support on intra-abdominal pressure, hepatic kinetics of indocyanine green and extravascular lung water during prone positioning in patients with ARDS: a randomized crossover study.

INTRODUCTION: Prone positioning (PP) on an air-cushioned mattress is associated with a limited increase in intra-abdominal pressure (IAP) and an absence of organ dysfunction. The respective influence of posture by itself and the type of mattress on these limited modifications during the PP procedure remains unclear. The aim of this study was to evaluate whether the type of support modifies IAP, extravascular lung water (EVLW) and the plasma disappearance rate of indocyanine green (PDRICG) during PP. METHODS: A prospective, randomized, crossover study of 20 patients with acute respiratory distress syndrome (ARDS) was conducted in a medical intensive care unit in a teaching hospital. Measurements were made at baseline and repeated after 1 and 6 hours of two randomized periods of 6 hours of PP with one of two support types: conventional foam mattress or air-cushioned mattress. RESULTS: After logarithmic transformation of the data, an analysis of variance (ANOVA) showed that IAP and PDRICG were significantly influenced by the type of support during PP with an increase in IAP (P < 0.05 by ANOVA) and a decrease in PDRICG on the foam mattress (P < 0.05 by ANOVA). Conversely, the measurements of EVLW did not show significant modification between the two supports whatever the posture. The ratio of the arterial oxygen tension to the fraction of inspired oxygen significantly increased in PP (P < 0.0001 by ANOVA) without any influence of the support. CONCLUSION: In comparison with a conventional foam mattress, the use of an air-cushioned mattress limited the increase in IAP and prevented the decrease in PDRICG related to PP in patients with ARDS. Conversely, the type of support did not influence EVLW or oxygenation.

Adult↗

Development and validation of a perioperative satisfaction questionnaire.

BACKGROUND: Satisfaction is considered a valuable measure of outcome of healthcare processes. Only a few anesthesia-related validated questionnaires are reported. Because their scope is restricted to specific clinical contexts, their use remains limited. The objective of the current study was to develop and validate a self-reported questionnaire, Evaluation du Vecu de l'Anesthesie Generale (EVAN-G), assessing the satisfaction of the perioperative period surrounding general anesthesia. METHODS: Development of the EVAN-G questionnaire comprised a phase of item generation and a phase of psychometric validation. The patient sample was generated to be proportionally matched to the population of patients undergoing general anesthesia in France. The structure of the questionnaire was identified studying interitem, item-dimension, and interdimension correlations and factor analyses. Data were concurrently gathered to assess external validity. The discriminant validity was determined by comparison of scores across well known patient groups. Reliability was assessed by computation of Cronbach alpha coefficients and by test-retest. RESULTS: Eight hundred seventy-four patients were recruited in eight anesthesia departments. The EVAN-G includes 26 items; six specific scores and one global index score are available. Correlations between EVAN-G scores and other concurrent measures supported convergent validity. The EVAN-G correlated poorly with age, American Society of Anesthesiologists physical status, total anesthesia time, and number of previous anesthesias. Significantly higher satisfaction was reported by patients older than 65 yr, belonging to the laryngeal mask group. Reliability and reproducibility were shown. CONCLUSION: The EVAN-G adds important information oriented toward patients' perceptions. The authors' approach provides a novel, valid, and reliable tool that may be used in anesthesia practice.

Adult↗

NH2 terminal pro-brain natriuretic peptide plasma level as an early marker of prognosis and cardiac dysfunction in septic shock patients.

OBJECTIVE: To investigate N-terminal pro-brain natriuretic peptide (NT-proBNP) level as a prognostic factor and a marker of myocardial dysfunction in patients with septic shock. DESIGN: Prospective observational study. SETTING: Intensive care unit. SUBJECTS: A total of 39 patients diagnosed with septic shock and requiring mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: Demographic, hemodynamic, respiratory, and biological data (notably NT-proBNP, lactate, and cardiac troponin I) were collected at inclusion and every 12 hrs. The independent factors for death were higher Sequential Organ Failure Assessment score in the 24-hr period after inclusion (odds ratio, 4.7; 95% confidence interval, 1.15-19.3) and the highest NT-proBNP level in the 24-hr period after inclusion (odds ratio, 1.12 per 1000 pg/mL increase; 95% confidence interval, 1.05-1.26). An NT-proBNP of >13,600 pg/mL predicted intensive care unit mortality with an accuracy of 77%. Area under the receiver operating characteristic curve was 0.8 (p = .002; 95% confidence interval, 0.66-0.93). NT-proBNP levels were over the accepted normal range in all patients. Values were highest between 24 and 36 hrs after onset of septic shock and were significantly higher in nonsurvivors at each time between inclusion and day 7. The lowest left ventricular stroke work index of the first 24-hr period after inclusion was the only factor that independently influenced higher NT-proBNP levels at the same time (odds ratio, 0.91; 95% confidence interval, 0.84-0.98). CONCLUSION: NT-proBNP seems to be an early factor of prognosis and myocardial dysfunction in patients with septic shock.

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Usefulness of ultrasonography in predicting pleural effusions > 500 mL in patients receiving mechanical ventilation.

STUDY OBJECTIVE: To assess the accuracy of chest ultrasonography in predicting pleural effusions > 500 mL in patients receiving mechanical ventilation. DESIGN: Prospective study. SETTING: Surgical and medical ICU in a teaching hospital. PATIENTS: Forty-four patients receiving mechanical ventilation with indications of chest drainage of a nonloculated pleural effusion. INTERVENTIONS: Diagnosis of pleural effusion was based on clinical examination and chest radiography. Chest drainage was indicated when considered as potentially useful for the patient (hypoxemia and/or weaning failure). Sonograms were performed before drainage at the bedside, in the supine position, and measurements were performed at the end of expiration. Effusions were classified as > 500 mL or < or = 500 mL according to the drained volume. MEASUREMENTS AND RESULTS: The drained volume ranged from 100 to 1,800 mL (mean, 730 +/- 440 mL [+/- SD]). The distance between the lung and posterior chest wall at the lung base (PLDbase) and the distance between the lung and posterior chest wall at the fifth intercostal space (PLD5) were significantly correlated with the drained volume (PLDbase, r = 0.68, p < 0.001; PLD5, r = 0.56, p < 0.001). A PLDbase > 5 cm predicted a drained volume > 500 mL with a sensitivity of 83%, specificity of 90%, positive predictive value of 91%, and negative predictive value of 82%. Interobserver and intraobserver percentages of error were, respectively, 7 +/- 6% and 9 +/- 6% for PLDbase, and 6 +/- 5% and 8 +/- 5% for PLD5. The PaO2/fraction of inspired oxygen ratio significantly increased after chest drainage in patients with collected volumes > 500 mL (p < 0.01). CONCLUSIONS: Bedside pleural ultrasonography accurately predicted a nonloculated pleural effusion > 500 mL in patients receiving mechanical ventilation using simple and reproducible measurements.

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Accuracy and limits of transpulmonary dilution methods in estimating extravascular lung water after pneumonectomy.

STUDY OBJECTIVES: The measurement of extravascular lung water index by double indicator (EVLWIdi) or the measurement of extravascular lung water index by transpulmonary thermodilution (EVLWItt) could be useful after pneumonectomy. Since pulmonary blood flow and volume are altered after pneumonectomy, the validity of these methods is uncertain. This study has compared measurements of EVLWIdi and EVLWItt with measurement of extravascular lung water index by gravimetry (EVLWIg) in a porcine model of pulmonary edema induced after right pneumonectomy. DESIGN: Randomized laboratory study. SETTING: Animal research laboratory. SUBJECTS: Twenty-seven female pigs; mean weight, 35 +/- 5 kg (+/- SD). INTERVENTIONS: The pigs were anesthetized, placed on mechanical ventilation, and allocated to a two-lung group (n = 10) or a right pneumonectomy group (n = 17). EVLWIdi and EVLWItt were measured at baseline, 60 min after pneumonectomy, and 60 min after IV injection of oleic acid (OA). MEASUREMENTS AND RESULTS: There was a good correlation between EVLWIg and EVLWIdi values (r = 0.96, p < 0.0001 in the two-lung group; and r = 0.81, p = 0.02 in the pneumonectomy group). EVLWIdi underestimated EVLWIg in the two-lung group (- 3 mL/kg; 95% confidence interval [CI], - 7 to + 2 mL/kg) and in the pneumonectomy group (- 0.9 mL/kg; 95% CI, - 3.3 to + 1.5 mL/kg). After pneumonectomy, EVLWItt decreased in mean by 27% and increased in mean by 70% after OA acid. There was a good correlation between EVLWIg and EVLWItt values (r = 0.96, p < 0.0001 in the two-lung group; and r = 0.90, p < 0.0001 after pneumonectomy). EVLWItt slightly overestimated gravimetric value in the two-lung group (+ 1.5 mL/kg; 95% CI, - 1.5 to + 4.2 mL/kg) and largely overestimated gravimetric value after pneumonectomy (+ 5 mL/kg; 95% CI, + 3.4 to + 6.8 mL/kg). CONCLUSION: Double-indicator and transpulmonary thermodilution methods could be useful in monitoring extravascular lung water index (EVLWI) after pneumonectomy, but transpulmonary thermodilution largely overestimates EVLWI.

Animals↗

Perioperative risk factors for anastomotic leakage after esophagectomy: influence of thoracic epidural analgesia.

STUDY OBJECTIVES: Anastomotic leakage after esophagectomy is associated with high postoperative morbidity and mortality. The most important predisposing factors for anastomotic leaks are ischemia of the gastric conduit and low blood oxygen content. The aim of this study was to evaluate the influence of thoracic epidural analgesia (TEA) on the incidence of anastomotic leakage after esophagectomy. DESIGN: Retrospective study. SETTING: A thoracic surgery and anesthesia department in a teaching hospital. PATIENTS: Two hundred seven patients who underwent one-stage esophagectomy between 1998 and 2003. INTERVENTIONS: The effects of perioperative factors and postoperative complications on the incidence of anastomotic leakage were analyzed. Leakage was defined as an anastomotic disruption detected by an ionic x-ray contrast study and confirmed by upper endoscopy in the postoperative period. Analyzed factors included effective TEA placed before the surgical procedure. MEASUREMENTS AND RESULTS: Anastomotic leakage occurred in 23 patients (11%). This complication was associated with a significant increase in length of stay in the ICU and in the hospital (mean, 19 +/- 16 days vs 9 +/- 7 days [+/- SD], p = 0.008; and 43 +/- 27 days vs 23 +/- 11 days, respectively; p < 0.001). Mortality in patients presenting anastomotic leakage was 26%, compared with 5.4% in the remainder (p = 0.002). Factors independently associated with the incidence of leakage included estimated blood loss per milliliter during the surgical procedure (odds ratio [OR], 1.004; 95% confidence interval [CI], 1.001 to 1.007), the cervical location for anastomosis (OR, 5.4; 95% CI, 1.3 to 22.9), and the development of an ARDS in the postoperative period (OR, 4.1; 95% CI, 2.6 to 176.5). Ninety-three patients benefited from an effective TEA for 4.4 +/- 0.8 days. The use of TEA was independently associated with a decrease in the incidence of anastomotic leakage (OR, 0.13; 95% CI, 0.02 to 0.71). CONCLUSIONS: The results of this retrospective study suggest that TEA is associated with a decrease in occurrence of anastomotic leakage.

Adenocarcinoma↗

Mimivirus in pneumonia patients.

Mimivirus, the largest virus known to date, is an amebal pathogen-like Legionella sp. When Mimivirus was used as an antigen in a microimmunofluorescense assay, seroconversion was found in patients with both community- and hospital-acquired pneumonia. Mimivirus DNA was found in respiratory samples of a patient with hospital-acquired pneumonia.

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Accuracy of the double indicator method for measurement of extravascular lung water depends on the type of acute lung injury.

OBJECTIVE: The double indicator method is sensitive to alterations in the distribution of pulmonary blood flow. This distribution is influenced by the type of lung injury. The aim of this study was to compare measurements of lung water by the double indicator method with measurements obtained by gravimetry in a direct lung injury model induced by tracheal instillation of hydrochloric acid and in an indirect lung injury model induced by the intravenous injection of oleic acid. DESIGN: Prospective, randomized laboratory study. SETTING: Animal research laboratory. SUBJECTS: Forty-two female pigs (28+/-3 kg). INTERVENTIONS: Pigs were anesthetized and ventilated and were allocated into three groups: control (n = 6), hydrochloric acid (4 mL/kg intratracheally, n = 24), or oleic acid (0.1 mL/kg intravenously, n = 12). MEASUREMENTS AND MAIN RESULTS: Hydrochloric acid instillation or oleic acid injection resulted in a similar hypoxemia and induced a two- to three-fold increase in extravascular lung water (EVLW) by gravimetry (EVLWG) at 3 hrs compared with controls. In the oleic acid group, there was a significant correlation between EVLWG and EVLW by double indicator method (EVLWDI; r =.88, p <.0001). The bias for EVLWDI - EVLWG measurements was -5.2 mL/kg (95% confidence interval, -5.7 to -4.7 mL/kg) with 95% limits of agreement of -7 to -3.4 mL/kg. In the hydrochloric acid group, there was no significant correlation between EVLWDI and EVLWG values, and the double indicator method failed to detect pulmonary edema in 65% of the animals (EVLWDI <8 mL/kg). The bias was -7.9 mL/kg (95% confidence interval, -9.3 to -6.5 mL/kg) with 95% limits of agreement of -14.4 to -1.4 mL/kg. CONCLUSIONS: The double indicator method is useful for evaluation of pulmonary edema in indirect lung injury, as induced by oleic acid, but produces misleading values in direct lung injury, as produced by hydrochloric instillation.

Analysis of Variance↗

Long-term outcome in intensive care unit survivors after mechanical ventilation for intracerebral hemorrhage.

OBJECTIVE: To evaluate long-term survival and functional outcome in intensive care unit survivors after mechanical ventilation for intracerebral hemorrhage. DESIGN: Retrospective chart review and prospective follow-up study. SETTING: Outpatient follow-up. PATIENTS: Between 1997 and 2000, 120 patients were mechanically ventilated for an intracerebral hemorrhage at our intensive care unit. Sixty-two patients were discharged from hospital (in-hospital mortality = 48%). Sixty patients were evaluated for survival and functional outcome (two were lost to follow-up). Time between discharge and follow-up was > or =1 yr and was a mean of 27 +/- 14 months (range, 12-56). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients' physicians were first asked about survival, and patients or proxies were interviewed by phone. Barthel Index and modified Rankin Scale scores were collected, and demographic information and general data were reviewed. The estimated life-table survival curve after discharge was 64.6% at 1 yr and 57% at 3 yrs. In the 24 patients who died, the mean time between discharge and death was 5 +/- 6 months. Probability of death after discharge significantly increased if age at admission was >65 yrs (p <.01; odds ratio, 3.5; 95% confidence interval, 1.4-9.1) and if Glasgow Coma Scale score at discharge was <15 (p <.01; odds ratio, 3.9; 95% confidence interval, 1.6-9.5). In the 36 long-term survivors, Barthel Index was 67.5 +/- 15 (median +/- median absolute dispersion) and modified Rankin Scale score was 2.6 +/- 0.5. Fifteen patients (42%) had a slight or no disability (Barthel Index > or =90 and modified Rankin Scale score < or =2), whereas 21 patients (58%) had moderate or severe disability (Barthel Index < or =85 and modified Rankin Scale score >2). CONCLUSIONS: Probability of survival at 3 yrs after mechanical ventilation for an intracerebral hemorrhage was >50%. Age was an important determinant of long-term survival. Forty-two percent of long-term survivors were independent for activities of daily living. Only a few long-term survivors had a very high degree of disability.

Adult↗

Cardiopulmonary effects of lipid emulsions in patients with ARDS.

STUDY OBJECTIVES: Lipid emulsions have been suspected of inducing certain modifications in gas exchange and pulmonary hemodynamics. The aim of this prospective study was to evaluate the hemodynamic and pulmonary effects of two lipid emulsions. DESIGN: Prospective, randomized, double-blind, crossover study. SETTING: Medical and surgical ICU in a French university hospital. PATIENTS: Eighteen patients presenting ARDS. INTERVENTIONS: Each patient received a 6-h infusion of a 20% fat emulsion containing 100% long-chain triglycerides (LCTs) and a 6-h infusion of 50% LCTs/50% medium-chain triglycerides (MCTs) 20% lipid emulsion at the rate of 1.0 mL/kg/h. An 18-h period with no lipids separated the two periods. An additional 18-h period after the end of the second lipid emulsion administration was observed prior to the final measurements. MEASUREMENTS AND RESULTS: The MCT/LCT emulsion increased the PaO(2)/fraction of inspired oxygen (FIO(2)) ratio (p = 0.005) compared with LCT emulsion alone. The mean (+/- SD) PaO(2)/FIO(2) ratio increased from 165 +/- 55 to 191 +/- 64 mm Hg after 1 h of LCT/MCT administration (p < 0.03), and to 175 +/- 46 mm Hg after 6 h. Moreover, there was an increase in oxygen delivery after 6 h of LCT/MCT administration (p < 0.001 vs baseline). While a time-related increase in mean pulmonary artery pressure (p = 0.012) during lipid administration was found, no effect of the kind of lipid emulsion was observed. The time-related increase in cardiac index (p = 0.002) was more marked when the patients received the LCT/MCT emulsion (p = 0.002). Pulmonary vascular resistances were not affected by the kind of lipid emulsion. CONCLUSIONS: The present work showed that while the LCT emulsion induced no deleterious effects on oxygenation in ARDS patients, the LCT/MCT emulsion improved the PaO(2)/FIO(2) ratio and had a further beneficial effect on oxygen delivery.

Cross-Over Studies↗

Conventional mechanical ventilation of healthy lungs induced pro-inflammatory cytokine gene transcription.

We investigated the potential inflammatory reaction induced by mechanical ventilation (MV) using 10 ml/kg tidal volume and no positive end-expiratory pressure (PEEP) in control (C, n = 8), spontaneously breathing (SB, n = 12) and mechanically ventilated (MV, n = 12) rabbits with normal lungs. After 6 h (MV and SB groups) or immediately (C group), lungs were removed for measurement of wet-to-dry (W/D) weight ratio and for bronchoalveolar lavage (BAL). Pulmonary mechanics were also studied. MV animals developed a modest but significant (P < 0.01) impairment of arterial blood oxygenation and had higher W/D lung weight ratio than C ones. In MV group, BAL macrophage count was greater (P < 0.05) than in SB one. MV induced an upregulation of MCP-1, TNF-alpha, and IL-1beta gene transcription (mRNAs), without significant elevation of the corresponding protein cytokines in the BAL supernatant, except for MCP-1 (P < 0.05). These data suggest that MV, even using moderate tidal volume, elicits a pro-inflammatory stimulus to the lungs.

Analysis of Variance↗

Patients in the intensive care unit are exposed to amoeba-associated pathogens.

OBJECTIVE: To study the role of amoeba-associated alpha Proteobacteria as infecting agents in intensive care units (ICUs). DESIGN: Amoeba-associated alpha Proteobacteria were isolated from water samples taken from ICU taps and general hospital reservoir tanks using an amoebal co-culture procedure. Isolates were identified by 16S rDNA gene sequence comparison, and one isolate of each species was used as an antigen in a microimmunofluorescence assay to test the sera of the patients in the ICUs and compare them with those of control subjects. SETTING: The four university hospitals in Marseilles, France. PATIENTS: The sera of 85 patients in the ICUs with nosocomial pneumonia were tested. RESULTS: We isolated 64 bacterial strains that were identified as Afipia species or close relatives within the Rhizobiaceae subgroup of alpha Proteobacteria. These bacteria were assigned to 8 different species. Eleven patients were found to have an elevated antibody titer to either Afipia genospecies 1, or 3 still unnamed bacteria. No specific antibodies were detected in 100 control subjects (P < .01). CONCLUSION: These preliminary results support the hypothesis that ICU patients are exposed to amoeba-associated alpha Proteobacteria.

Alphaproteobacteria↗

Can the tomographic aspect characteristics of patients presenting with acute respiratory distress syndrome predict improvement in oxygenation-related response to the prone position?

BACKGROUND: In some patients with acute respiratory distress syndrome, the prone position is able to improve oxygenation, whereas in others it is not. It could be hypothesized that the more opacities that are present in dependent regions of the lung when the patient is in the supine position, the better the improvement in oxygenation is observed when the patients are turned prone. Therefore, we conducted a prospective study to identify computed tomographic scan aspects that could accurately predict who will respond to the prone position. METHODS: We included 46 patients with acute respiratory distress syndrome (31 responders and 15 nonresponders). Computed tomographic scan was performed in the 6-h period preceding prone position. Blood gas analyses were performed before and at the end of the first 6-h period of prone position. RESULTS: Arterial oxygen partial pressure/fraction of inspired oxygen increased from 117 +/- 42 (mean +/- SD) in the supine position to 200 +/- 76 mmHg in the prone position (P < 0.001). There were 31 responders and 15 nonresponders. There was a vertebral predominance of the opacities (P < 0.0001). However, there was no difference between responders and nonresponders. When only the amount of consolidated lung located under the heart was evaluated, there was more consolidated tissue under the heart relative to total lung area in nonresponders than in responders (P = 0.01). CONCLUSIONS: There are no distinctive morphologic features in the pattern of lung disease measured by computed tomographic scanning performed with the patient in the supine position that can predict response to the prone position.

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