Bertrand Souweine

Bio: Bertrand Souweine is an academic researcher from Centre national de la recherche scientifique. The author has contributed to research in topics: Intensive care & Intensive care unit. The author has an hindex of 13, co-authored 23 publications receiving 1230 citations.

Attributable mortality of ventilator-associated pneumonia: respective impact of main characteristics at ICU admission and VAP onset using conditional logistic regression and multi-state models

Abstract: PURPOSE: Methods for estimating the excess mortality attributable to ventilator-associated pneumonia (VAP) should handle VAP as a time-dependent covariate, since the probability of experiencing VAP increases with the time on mechanical ventilation. VAP-attributable mortality (VAP-AM) varies with definitions, case-mix, causative microorganisms, and treatment adequacy. Our objectives here were to compare VAP-AM estimates obtained using a traditional cohort analysis, a multistate progressive disability model, and a matched-cohort analysis; and to compare VAP-AM estimates according to VAP characteristics. METHODS: We used data from 2,873 mechanically ventilated patients in the Outcomerea((R)) database. Among these patients from 12 intensive care units, 434 (15.1%) experienced VAP; of the remaining patients, 1,969 (68.5%) were discharged alive and 470 (16.4%) died. With the multistate model, VAP-AM was 8.1% (95% confidence interval [95%CI], 3.1-13.1%) for 120 days' complete observation, compared to 10.4% (5.6-24.5%) using a matched-cohort approach (2,769 patients) with matching on mechanical ventilation duration followed by conditional logistic regression. VAP-AM was higher in surgical patients and patients with intermediate (but not high) Simplified Acute Physiologic Score II values at ICU admission. VAP-AM was significantly influenced by time to VAP but not by resistance of causative microorganisms. Higher Logistic Organ Dysfunction score at VAP onset dramatically increased VAP-AM (to 31.9% in patients with scores above 7). CONCLUSION: A multistate model that appropriately handled VAP as a time-dependent event produced lower VAP-AM values than conditional logistic regression. VAP-AM varied widely with case-mix. Disease severity at VAP onset markedly influenced VAP-AM; this may contribute to the variability of previous estimates.

Anti-biofilm Activity as a Health Issue

Abstract: The formation and persistence of surface-attached microbial communities, known as biofilms, are responsible for 75% of human microbial infections (National Institutes of Health). Biofilm lifestyle confers several advantages to the pathogens, notably during the colonization process of medical devices and/or patients’ organs. In addition, sessile bacteria have a high tolerance to exogenous stress including anti-infectious agents. Biofilms are highly competitive communities and some microorganisms exhibit anti-biofilm capacities such as bacterial growth inhibition, exclusion or competition, which enable them to acquire advantages and become dominant. The deciphering and control of anti-biofilm properties represent future challenges in human infection control. The aim of this review is to compare and discuss the mechanisms of natural bacterial anti-biofilm strategies/mechanisms recently identified in pathogenic, commensal and probiotic bacteria and the main synthetic strategies used in clinical practice, particularly for catheter-related infections.

Association between hypernatraemia acquired in the ICU and mortality: a cohort study

Abstract: BACKGROUND: The aim of this study is to describe the prevalence and outcomes of intensive care unit (ICU)-acquired hypernatraemia (IAH). METHODS: A retrospective analysis was performed on a prospectively collected database fed by 12 ICUs. Subjects are unselected patients with ICU stay >48 h. Mild and moderate to severe hypernatraemia were defined as serum sodium >145 and >150 mmol/L, respectively. IAH was hypernatraemia occurring >/=24 h after ICU admission in patients with normal serum sodium at ICU admission. RESULTS: Of the 8441 patients, 301 were excluded because they had hypernatraemia at ICU admission. Of the remaining 8140 patients, 901 (11.1%) experienced mild hypernatraemia, and 344 (4.2%) experienced moderate to severe hypernatraemia. Factors independently associated with IAH were male gender, severity at admission as assessed by the Simplified Acute Physiology Score version II (SAPS II), and organ failure or life-supporting treatment at ICU admission. Unadjusted hospital mortality was 15.2% in patients without hypernatraemia compared to 29.5% in patients with mild IAH and 46.2% in those with moderate to severe IAH (P < 0.0001). When any degree of IAH was handled as a time-dependent variable in a subdistribution hazard model, the subdistribution hazard ratio (SHR) for ICU mortality was 4.26 [95% confidence interval (CI), 3.74-4.84]. After stratification by centre and adjustment for confounders, both mild IAH and moderate to severe IAH were independently associated with mortality [SHR 2.03 (95% CI 1.73-2.39) and 2.67 (95% CI 2.19-3.26), respectively]. CONCLUSION: IAH is frequent and associated with mortality after adjustment on severity at ICU admission.

Multidrug-resistant Klebsiella pneumoniae outbreak after endoscopic retrograde cholangiopancreatography

Abstract: Background and study aims Infection is a recognized complication of endoscopic retrograde cholangiopancreatography (ERCP). We describe the epidemiologic and molecular investigations of an outbreak of ERCP-related severe nosocomial infection due to KLEBSIELLA PNEUMONIAE producing extended-spectrum beta-lactamase (ESBL). Patients and methods We conducted epidemiologic and molecular investigations to identify the source of the outbreak in patients undergoing ERCP. We carried out reviews of the medical and endoscopic charts and microbiological data, practice audits, surveillance cultures of duodenoscopes and environmental sites, and molecular typing of clinical and environmental isolates. Results Between December 2008 and August 2009, 16 patients were identified post-ERCP with KLEBSIELLA PNEUMONIAE that produced extended-spectrum beta-lactamase type CTX-M-15. There were 8 bloodstream infections, 4 biliary tract infections, and 4 cases of fecal carriage. The microorganism was isolated only from patients who had undergone ERCP. Environmental investigations found no contamination of the washer-disinfectors or the surfaces of the endoscopy rooms. Routine surveillance cultures of endoscopes were repeatedly negative during the outbreak but the epidemic strain was finally isolated from one duodenoscope by flushing and brushing the channels. Molecular typing confirmed the identity of the clinical and environmental strains. Practice audits showed that manual cleaning and drying before storage were insufficient. Strict adherence to reprocessing procedures ended the outbreak. Conclusions The endoscopes used for ERCP can act as a reservoir for the emerging ESBL-producing K. PNEUMONIAE. Regular audits to ensure rigorous application of cleaning, high-level disinfection, and drying steps are crucial to avoid contamination.

Selected medical errors in the intensive care unit: results of the IATROREF study: parts I and II.

Abstract: Rationale: Although intensive care units (ICUs) were created for patients with life-threatening illnesses, the ICU environment generates a high risk of iatrogenic events. Identifying medical errors (MEs) that serve as indicators for iatrogenic risk is crucial for purposes of reporting and prevention.Objectives: We describe the selection of indicator MEs, the incidence of such MEs, and their relationship with mortality.Methods: We selected indicator MEs using Delphi techniques. An observational prospective multicenter cohort study of these MEs was conducted from March 27 to April 3, 2006, in 70 ICUs; 16 (23%) centers were audited. Harm from MEs was collected using specific scales.Measurements and Main Results: Fourteen types of MEs were selected as indicators; 1,192 MEs were reported for 1,369 patients, and 367 (26.8%) patients experienced at least 1 ME (2.1/1,000 patient-days). The most common MEs were insulin administration errors (185.9/1,000 d of insulin treatment). Of the 1,192 medical errors, 183 (15...

Acute Kidney Injury Network: report of an initiative to improve outcomes in acute kidney injury

Abstract: Acute kidney injury (AKI) is a complex disorder for which currently there is no accepted definition. Having a uniform standard for diagnosing and classifying AKI would enhance our ability to manage these patients. Future clinical and translational research in AKI will require collaborative networks of investigators drawn from various disciplines, dissemination of information via multidisciplinary joint conferences and publications, and improved translation of knowledge from pre-clinical research. We describe an initiative to develop uniform standards for defining and classifying AKI and to establish a forum for multidisciplinary interaction to improve care for patients with or at risk for AKI. Members representing key societies in critical care and nephrology along with additional experts in adult and pediatric AKI participated in a two day conference in Amsterdam, The Netherlands, in September 2005 and were assigned to one of three workgroups. Each group's discussions formed the basis for draft recommendations that were later refined and improved during discussion with the larger group. Dissenting opinions were also noted. The final draft recommendations were circulated to all participants and subsequently agreed upon as the consensus recommendations for this report. Participating societies endorsed the recommendations and agreed to help disseminate the results. The term AKI is proposed to represent the entire spectrum of acute renal failure. Diagnostic criteria for AKI are proposed based on acute alterations in serum creatinine or urine output. A staging system for AKI which reflects quantitative changes in serum creatinine and urine output has been developed. We describe the formation of a multidisciplinary collaborative network focused on AKI. We have proposed uniform standards for diagnosing and classifying AKI which will need to be validated in future studies. The Acute Kidney Injury Network offers a mechanism for proceeding with efforts to improve patient outcomes.

Duration of hypotension before initiation of effective antimicrobial therapy is the critical determinant of survival in human septic shock.

Abstract: Objective:To determine the prevalence and impact on mortality of delays in initiation of effective antimicrobial therapy from initial onset of recurrent/persistent hypotension of septic shock.Design:A retrospective cohort study performed between July 1989 and June 2004.Setting:Fourteen intensive car

Management of Chronic Kidney Disease Patients in the Intensive Care Unit: Mixing Acute and Chronic Illness

Abstract: Patients with chronic kidney disease (CKD) are at high risk for developing critical illness and for admission to intensive care units (ICU). ‘Critically ill CKD patients' frequently develop an acute w

Intensive insulin therapy for the critically ill patients with stress hyperglycemia

Abstract: Objective To observe the effect of intensive insulin therapy on the critically ill patients with stress hyperglycemia in ICU.Methods One hundred and ten critically ill patients in ICU were randomly divided into two groups,the intensive insulin therapy group(n=55) and control group(n=55).The blood glucose in the intensive insulin therapy group was controlled at 4.4 to 6.1 mmol/L,and the blood glucose in control group was controlled at 10.0 to 11.1 mmol/L.The two groups were observed and compared the days in the ICU,the numbers of patients requiring mechanical ventilation,the days of mechanical ventilation,the incidences of infection in hospital,the days of using antibiotics,Acute Physiology and Chronic Health Evaluation Ⅱ score of the last day in ICU,the morbidity of multiple organ failure,the morbidity of hypoglycemia and mortality.Results All the above indices except morbidity of hypoglycemia were significantly lower in the intensive insulin therapy group than those in control group(P0.05 or P0.01).Conclusion Intensive insulin therapy and keeping blood glucose at 4.4 to 6.1 mmol/L can improve the clinical curative effect and reduce the mortality for the critically ill patients with stress hyperglycemia,