Positive end-expiratory pressure in acute respiratory distress syndrome: should the 'open lung strategy' be replaced by a 'protective lung strategy'?

In patients with acute respiratory distress syndrome, positive end-expiratory pressure is associated with alveolar recruitment and lung hyperinflation despite the administration of a low tidal volume. The best positive end-expiratory pressure should correspond to the best compromise between recruitment and distension, a condition that coincides with the best respiratory elastance

Computed tomography assessment of exogenous surfactant-induced lung reaeration in patients with acute lung injury

Introduction: Previous randomized trials failed to demonstrate a decrease in mortality of patients with acute lung injury treated by exogenous surfactant. the aim of this prospective randomized study was to evaluate the effects of exogenous porcine-derived surfactant on pulmonary reaeration and lung tissue in patients with acute lung injury and acute respiratory distress syndrome (ALI/ARDS).Methods: Twenty patients with ALI/ARDS were studied (10 treated by surfactant and 10 controls) in whom a spiral thoracic computed tomography scan was acquired before (baseline), 39 hours and 7 days after the first surfactant administration. in the surfactant group, 3 doses of porcine-derived lung surfactant (200 mg/kg/dose) were instilled in both lungs at 0, 12 and 36 hours. Each instillation was followed by recruitment maneuvers. Gas and tissue volumes were measured separately in poorly/nonaerated and normally aerated lung areas before and seven days after the first surfactant administration. Surfactant-induced lung reaeration was defined as an increase in gas volume in poorly/non-aerated lung areas between day seven and baseline compared to the control group.Results: At day seven, surfactant induced a significant increase in volume of gas in poorly/non-aerated lung areas (320 +/- 125 ml versus 135 +/- 161 ml in controls, P = 0.01) and a significant increase in volume of tissue in normally aerated lung areas (189 +/- 179 ml versus -15 +/- 105 ml in controls, P < 0.01). PaO2/FiO(2) ratio was not different between the surfactant treated group and control group after surfactant replacement.Conclusions: Intratracheal surfactant replacement induces a significant and prolonged lung reaeration. It also induces a significant increase in lung tissue in normally aerated lung areas, whose mechanisms remain to be elucidated.Univ Paris 06, Multidisciplinary Intens Care Unit, Dept Anesthesiol & Crit Care Med, La Pitie Salpetriere Hosp,Assistance Publ Hop Par, F-75013 Paris, FranceZhejiang Univ, Sch Med, Affiliated Hosp 2, Dept Emergency Med, Hangzhou 310009, Zhejiang, Peoples R ChinaUniversidade Federal de São Paulo, Dept Anesthesiol, Escola Paulista Med, BR-04024002 São Paulo, BrazilUniv Med Ctr Utrecht, Dept Intens Care Med, NL-3584 CX Utrecht, NetherlandsUniversidade Federal de São Paulo, Dept Anesthesiol, Escola Paulista Med, BR-04024002 São Paulo, BrazilWeb of Scienc

Correction to: Use of combined cardiac and lung ultrasound to predict weaning failure in elderly, high-risk cardiac patients: a pilot study

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Effects of contrast material on computed tomographic measurements of lung volumes in patients with acute lung injury

BACKGROUND: Intravenous injection of contrast material is routinely performed in order to differentiate nonaerated lung parenchyma from pleural effusion in critically ill patients undergoing thoracic computed tomography (CT). The aim of the present study was to evaluate the effects of contrast material on CT measurement of lung volumes in 14 patients with acute lung injury. METHOD: A spiral thoracic CT scan, consisting of contiguous axial sections of 10 mm thickness, was performed from the apex to the diaphragm at end-expiration both before and 30 s (group 1; n = 7) or 15 min (group 2; n = 7) after injection of 80 ml contrast material. Volumes of gas and tissue, and volumic distribution of CT attenuations were measured before and after injection using specially designed software (Lungview(®); Institut National des Télécommunications, Evry, France). The maximal artifactual increase in lung tissue resulting from a hypothetical leakage within the lung of the 80 ml contrast material was calculated. RESULTS: Injection of contrast material significantly increased the apparent volume of lung tissue by 83 ± 57 ml in group 1 and 102 ± 80 ml in group 2, whereas the corresponding maximal artifactual increases in lung tissue were 42 ± 52 ml and 31 ± 18 ml. CONCLUSION: Because systematic injection of contrast material increases the amount of extravascular lung water in patients with acute lung injury, it seems prudent to avoid this procedure in critically ill patients undergoing a thoracic CT scan and to reserve its use for specific indications

An international tool to measure perceived stressors in intensive care units: the PS-ICU scale.

Background The intensive care unit is increasingly recognized as a stressful environment for healthcare professionals. This context has an impact on the health of these professionals but also on the quality of their personal and professional life. However, there is currently no validated scale to measure specific stressors perceived by healthcare professionals in intensive care. The aim of this study was to construct and validate in three languages a perceived stressors scale more specific to intensive care units (ICU). Results We conducted a three-phase study between 2016 and 2019: (1) identification of stressors based on the verbatim of 165 nurses and physicians from 4 countries (Canada, France, Italy, and Spain). We identified 99 stressors, including those common to most healthcare professions (called generic), as well as stressors more specific to ICU professionals (called specific); (2) item elaboration and selection by a panel of interdisciplinary experts to build a provisional 99-item version of the scale. This version was pre-tested with 70 professionals in the 4 countries and enabled us to select 50 relevant items; (3) test of the validity of the scale in 497 ICU healthcare professionals. Factor analyses identified six dimensions: lack of fit with families and organizational functioning; patient- and family-related emotional load; complex/at risk situations and skill-related issues; workload and human resource management issues; difficulties related to team working; and suboptimal care situations. Correlations of the PS-ICU scale with a generic stressors measure (i.e., the Job Content Questionnaire) tested its convergent validity, while its correlations with the Maslach Burnout Inventory-HSS examined its concurrent validity. We also assessed the test–retest reliability of PS-ICU with intraclass correlation coefficients. Conclusions The perceived stressors in intensive care units (PS-ICU) scale have good psychometric properties in all countries. It includes six broad dimensions covering generic or specific stressors to ICU, and thus, enables the identification of work situations that are likely to generate high levels of stress at the individual and unit levels. For future studies, this tool will enable the implementation of targeted corrective actions on which intervention research can be based. It also enables national and international comparisons of stressors’ impact.post-print925 K

Cardiac Troponin Release is Associated with Biomarkers of Inflammation and Ventricular Dilatation During Critical Illness.

INTRODUCTION: Troponin release is common during critical illness. We hypothesized that there was an association between cardiac troponin T (cTnT) and biomarkers of systemic inflammation and ventricular dilatation. METHODS: In an observational prospective cohort study, we enrolled consecutive adult patients admitted for non-cardiac reasons to the Intensive Care Unit (ICU) in 2 tertiary care centers. We measured cTnT, C-reactive protein (CRP), Interleukin-6 (IL-6), procalcitonin (PCT) and N-terminal pro brain natriuretic peptide (NT-proBNP) daily in the first week, and on alternate days in the second week. Using a peak cTnT cut-off ≥15ng/L and concomitant changes on electrocardiogram (ECG), patients were categorised as "definite myocardial infarction (MI)", "possible MI", "cTnT rise only" or "no cTnT rise". Within each group, associations between CRP, IL-6, PCT, NT-proBNP and cTnT were investigated using mixed effect models. RESULTS: 172 patients were included in the analysis of whom 84% had a cTnT rise ≥15ng/L. 21 patients (12%) had a definite MI, 51 (30%) had a possible MI and 73 (42%) had a cTnT rise only. At time of peak cTnT, 71% of patients were septic and 67% were on vasopressors.Multivariable analysis showed a significant association between cTnT and IL-6 in all patients with a cTnT rise independent of age, gender, renal function and cardiovascular risk factors. In patients without a definite MI, cTnT levels were significantly associated with PCT and NT-proBNP values. In patients without elevated cTnT levels, there was no associated NT-proBNP rise. CONCLUSIONS: In ICU patients admitted for non-cardiac reasons, serial cTnT levels were independently associated with markers of systemic inflammation and NT-proBNP