Jean-Pierre Auffray

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)-1&bgr;, IL-6, IL-8, and tumor necrosis factor &agr; were measured perioperatively and postoperatively. Pulmonary function and postoperative evolution were also evaluated. Patients who received protective strategy had lower blood levels of IL-1&bgr;, 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.

Ameba-associated Microorganisms and Diagnosis of Nosocomial Pneumonia

Ameba-associated microorganisms should be suspected when conventional microbiologic test results are negative.

Open-lung Biopsy in Patients with Acute Respiratory Distress Syndrome

Background It has been suggested that fibrosis present during the fibroproliferative phase of acute respiratory distress syndrome (ARDS) can be treated by corticosteroids. However, neither clinical nor microbiologic criteria permit differentiation of this fibroproliferative phase from a nosocomial pneumonia. The aim of this observational case series was to evaluate the safety and utility of open‐lung biopsy (OLB) performed in patients receiving ventilatory support who had persistent ARDS despite negative bacterial cultures. Methods During a 4‐yr period, 37 OLBs were performed in 36 of 197 patients receiving ventilatory support who had ARDS. The severity of ARDS was assessed by a lung injury score of 3.1 +/‐ 0.4 (mean +/‐ SD) and a median ratio of the partial pressure of oxygen (PaO2) to the fraction of inspired oxygen (FiO2) of 118 mmHg. Histologic examination; bacterial, fungal, and acid‐fast staining; and cultures of the tissue sample were performed. Results Fibrosis was present in only 41% of the lung specimens obtained by OLB. Only six patients received corticosteroids (17%). In 9 of the 15 patients with fibrosis, cytomegalovirus pneumonia precluded the use of corticosteroids. Histologic cytomegalovirus pneumonia was diagnosed in 18 cases. Histologic bacterial or mycobacterial pneumonia was diagnosed in five cases. No significant change in arterial blood gases was noted as linked to the biopsy procedure except an increase of the PaO2 /FI O2 ratio. One pneumothorax was diagnosed on a chest roentgenogram 12 h after OLB. Only one patient required blood transfusion during the 48‐h period after OLB (for an hemothorax). Five patients had moderate air leaks from operative chest tubes for 2–10 days. Conclusions Open lung biopsy appeared to be a useful and acceptably safe diagnostic technique in patients with ARDS. It permitted the diagnosis of unexpected cytomegalovirus pneumonia.

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 Vécu de l’Anesthésie Générale (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 α 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.

Monitoring of central venous oxygen saturation versus mixed venous oxygen saturation in critically ill patients

Continous monitoring of mixed venous (SvO2) and central venous (ScO2) oxygen saturation was compared in 7 critically-ill patients (Apache II score: 19±2.1) to determine whether or not information derived from ScO2 were reliable in clinical practice. Patients were catheterized with both a pulmonary artery (PA) and a central venous (CV) catheter, each of them mounted with fiberoptic sensors (Opticath PA Catheter P7110 and Opticath CV Catheter U440, Abbott). A total of 580 comparative measurements were obtained during periods without and with therapeutic interventions (drug-titration, bronchial suction, use of PEEP, changes in FiO2...). The systematic error between the 2 measurement techniques was 0.6% and 0.3% in periods with and without therapeutic interventions, respectively. The variability between the 2 techniques was 10% for both periods. Differences between the values were ≧5% in 49% of values during periods of stability and in 50% of values during periods with therapeutic interventions. There were poor correlations between the values during periods without (r=0.48) and with therapeutic interventions (r=0.62). Better, but still less than ideal, correlations were obtained with changes in SvO2 and ScO2 during periods without (r=0.70) and with therapeutic interventions (r=0.77). Although there is a need to develop a simple technique to monitor mixed venous oxygen saturation, the present study indicates that ScO2 monitoring was not reliable in the study patients.

Is ventilator-associated pneumonia an independent risk factor for death?

BackgroundVentilator-associated pneumonia (VAP) has been implicitly accused of increasing mortality. However, it is not certain that pneumonia is responsible for death or whether fatal outcome is caused by other risk factors for death that exist before the onset of pneumonia. The aim of this study was to evaluate the attributable mortality caused by VAP by performing a matched-paired, case-control study between patients who died and patients who were discharged from the intensive care unit after more than 48 h of mechanical ventilation. MethodsDuring the study period, 135 consecutive deaths were included in the case group. Case-control matching criteria were as follows: (1) diagnosis on admission that corresponded to 1 of 11 predefined diagnostic groups; (2) age difference within 10 yr; (3) sex; (4) admission within 1 yr; (5) APACHE II score within 7 points; (6) ventilation of control patients for at least as long as the cases. Precise clinical, radiologic, and microbiologic definitions were used to identify VAP. ResultsAnalysis was performed on 108 pairs that were matched with 91% of success. There were 39 patients (36.1%) who developed VAP in each group. Multivariate analysis showed that renal failure, bone marrow failure, and treatment with corticosteroids but not VAP were independent risk factors for death. There was no difference observed between cases and controls concerning the clinical and microbiologic diagnostic criteria for pneumonia. ConclusionVentilator-associated pneumonia does not appear to be an independent risk factor for death.

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

IntroductionProne 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.MethodsA 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.ResultsAfter 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.ConclusionIn 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.

Tropheryma whipplei in patients with pneumonia.

This bacterium may be an etiologic agent of pneumonia.

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.

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

ObjectiveTo evaluate long-term survival and functional outcome in intensive care unit survivors after mechanical ventilation for intracerebral hemorrhage. DesignRetrospective chart review and prospective follow-up study. SettingOutpatient follow-up. PatientsBetween 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 ≥1 yr and was a mean of 27 ± 14 months (range, 12–56). InterventionsNone. Measurements and Main ResultsPatients’ 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 ≥90 and modified Rankin Scale score ≤2), whereas 21 patients (58%) had moderate or severe disability (Barthel Index ≤85 and modified Rankin Scale score >2). ConclusionsProbability 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.