Extrapulmonary ARDS Research Articles

Bacteremia in critically ill immunocompromised patients with acute hypoxic respiratory failure: A post-hoc analysis of a prospective multicenter multinational cohort

The characteristics and impact of bacteremia have not been widely investigated in immunocompromised patients with acute respiratory failure (ARF). We performed a secondary analysis of a prospective cohort of immunocompromised patients with ARF (EFRAIM study). After exclusion of blood cultures positive for coagulase negative Staphylococci, we compared patients with (n = 236) and without (n = 1127) bacteremia. The incidence of bacteremia was 17%. Bacterial pneumonia and extra-pulmonary ARDS were the main causes of ARF in bacteremic patients. Bacteremia involved gram negative rods (48%), gram positive cocci (40%) or were polymicrobial (10%). Bacteremic patients had more hematological malignancy, higher SOFA scores and increased organ support within 7 days. Bacteremia was associated with higher crude ICU mortality (40% versus 32%, p = 0.02), but neither hospital (49% versus 44%, p = 0.17) nor 90-day mortality (60% versus 56%, p = 0.25) were different from non-bacteremic patients. After propensity score matching based on baseline characteristics, the difference in ICU mortality lost statistical significance (p = 0.06), including in a sensitivity analysis restricted to patients with pneumonia. We analyzed a large population of immunocompromised patients with ARF and an incidence of bacteremia of 17%. We could not demonstrate an impact of bacteremia on mortality after adjusting for baseline characteristics.

Pulmonary versus Extrapulmonary Acute Respiratory Distress Syndrome: Clinical Characteristics and Outcome

Abstract Background: Acute respiratory distress syndrome is a clinical syndrome characterized by a refractory hypoxemia due to an inflammatory and high permeability pulmonary edema secondary to direct or indirect lung insult (pulmonary and extrapulmonary form). These two categories of ARDS patients are different regarding the respiratory mechanics, lung recruitment, gas exchange, and positive end-expiratory pressure response. Aim of Study: The aim of this work was to compare the clinical characteristics and outcomes between the two major ARDS subtypes; pulmonary and extrapulmonary. Patients and Methods: A prospective study was conducted during the period from July 2014 to January 2016 in Intensive Care Unit, El-Hussein University Hospital. It included 60 patients diagnosed as ARDS. They were subclassified into pulmonary and extrapulmonary ARDS groups according to the cause of lung injury. Both groups were compared regarding the clinical features, response to treatment and clinical outcome. Results: Patients with extrapulmonary ARDS developed more deteriorated liver and renal functions and arterial blood gases with a better response to elevated levels of PEEP and vasopressors with a mortality rate of 75%. In patients with pulmonary ARDS, mild organs dysfunction were developed with a better response to low levels of PEEP and a mortality rate of 25%. Conclusion: Subdivision of ARDS into pulmonary and extrapulmonary categories has worthy effect on both treatment and clinical outcome. Additionally, they are different in the degree of organ dysfunction and severity of clinical pictures. Recommendation: Proper assessment of patients with ARDS at admission to put them within a major category whether pulmonary or extrapulmonary ARDS. This simple classification will help physician to decide on treatment and to predict prognosis.

Comparison of the Effects of Corticosteroid Therapy on Pulmonary and Extrapulmonary ARDS Patients

Comparison of the Effects of Corticosteroid Therapy on Pulmonary and Extrapulmonary ARDS Patients

Clinical Predictors of Hospital Mortality Differ Between Direct and Indirect ARDS

Direct (pulmonary) and indirect (extrapulmonary) ARDS are distinct syndromes with important pathophysiologic differences. The goal of this study was to determine whetherclinical characteristics and predictors of mortality differ between direct or indirect ARDS. This retrospective observational cohort study included 417 patients with ARDS. Each patient was classified as having direct (pneumonia or aspiration, n= 250) or indirect (nonpulmonary sepsis or pancreatitis, n= 167) ARDS. Patients with direct ARDS had higher lung injury scores (3.0 vs2.8; P< .001), lower Simplified Acute Physiology Score II scores (51 vs62; P< .001), lower Acute Physiology and Chronic Health Evaluation II scores (27 vs30; P< .001), and fewer nonpulmonary organ failures (1 vs2; P< .001) compared with patients with indirect ARDS. Hospital mortality was similar (28%vs31%). In patients with direct ARDS, age (OR, 1.29 per 10 years; P= .01; test for interaction, P= .03), lung injury scores (OR, 2.29 per point; P= .001; test for interaction, P= .058), and number of nonpulmonary organ failures (OR, 1.67; P= .01) were independent risk factors for increased hospital mortality. Preexisting diabetes mellitus was an independent risk factor for reduced hospital mortality (OR, 0.47; P= .04; test for interaction, P= .02). In indirect ARDS, only the number of organ failures was an independent predictor of mortality (OR, 2.08; P< .001). Despite lower severity of illness and fewer organ failures, patients with direct ARDS had mortality rates similar to patients with indirect ARDS. Factors previously associated with mortality during ARDS were only associated with mortality in direct ARDS. These findings suggest that direct and indirect ARDS have distinct features that may differentially affect risk prediction and clinical outcomes.

Acute respiratory distress syndrome in patients with malignancies.

Little attention has been given to ARDS in cancer patients, despite their high risk for pulmonary complications. We sought to describe outcomes in cancer patients with ARDS meeting the Berlin definition. Data from a cohort of patients admitted to 14 ICUs between 1990 and 2011 were used for a multivariable analysis of risk factors for hospital mortality. Of 1,004 included patients (86 % with hematological malignancies and 14 % with solid tumors), 444 (44.2 %) had neutropenia. Admission SOFA score was 12 (10-13). Etiological categories were primary infection-related ARDS (n = 662, 65.9 %; 385 bacterial infections, 213 invasive aspergillosis, 64 Pneumocystis pneumonia); extrapulmonary septic shock-related ARDS (n = 225, 22.4 %; 33 % candidemia); noninfectious ARDS (n = 76, 7.6 %); and undetermined cause (n = 41, 4.1 %). Of 387 (38.6 %) patients given noninvasive ventilation (NIV), 276 (71 %) subsequently required endotracheal ventilation. Hospital mortality was 64 % overall. According to the Berlin definition, 252 (25.1 %) patients had mild, 426 (42.4 %) moderate and 326 (32.5 %) severe ARDS; mortality was 59, 63 and 68.5 %, respectively (p = 0.06). Mortality dropped from 89 % in 1990-1995 to 52 % in 2006-2011 (p < 0.0001). Solid tumors, primary ARDS, and later admission period were associated with lower mortality. Risk factors for higher mortality were allogeneic bone-marrow transplantation, modified SOFA, NIV failure, severe ARDS, and invasive fungal infection. In cancer patients, 90 % of ARDS cases are infection-related, including one-third due to invasive fungal infections. Mortality has decreased over time. NIV failure is associated with increased mortality. The high mortality associated with invasive fungal infections warrants specific studies of early treatment strategies.

Factors Associated within 28 Days In-Hospital Mortality of Patients with Acute Respiratory Distress Syndrome

Objective. To determine the factors leading to in-hospital mortality within 28 days in hospitalized patients with ARDS. It was a prospective observational cohort study conducted in Intensive Care Unit of Aga Khan University Hospital Karachi from March to August 2011. Methodology. Data was collected from patients admitted in the intensive care unit on the basis of inclusion and exclusion criteria. The patients were followed daily for 28 days to record any in-hospital complications and the outcome of patients. Results. Total of 46 patients were included during this period out of which 56% (26) were males and 43% (20) were females. Mean age was 44 ± 19 years. There were 11 (23.9%) patients with age >65 and 35 (76%) had age <65 years. There were 21 (45.6%) patients with pulmonary ARDS and 25 (54.3%) had extrapulmonary ARDS. APACHE II score of >20 was present in 23 (50%) patients while the rest had score of <20. Regarding in-hospital complications, 23 (50%) patients developed sepsis, 31 (67.4%) had multiorgan failure, 14 (30%) had refractory shock, and 15 (32.6%) developed refractory hypoxemia. Out of 46 patients, 26 (56.5%) died within 28 days. On univariate analysis, high APACHE score, multiorgan failure, refractory shock, and refractory hypoxemia were main causes of death. Conclusion. ARDS is a syndrome of high mortality with mortality rate of 56.5% in this study. High APACHE, sepsis, multiorgan failure, refractory shock, and refractory hypoxemia are the leading causes of death in our patients.

Impact of positive end-expiratory pressure on the definition of acute respiratory distress syndrome.

We examined whether PEEP during the first hours of ARDS can induce such a change in oxygenation that could mask fulfillment of the AECC criteria of a PaO(2)/FIO(2) </= 200 essential for ARDS diagnosis. Observational, prospective cohort in two medical-surgical ICU in teaching hospitals. 48 consecutive patients who met AECC criteria of ARDS on 0 PEEP (ZEEP) at the moment of diagnosis. PaO(2)/FIO(2) and lung mechanics were recorded on admission (0 h) to the ICU on ZEEP, and after 6, 12, and 24 h on PEEP levels selected by attending physicians. Lung Injury Score (LIS) was calculated at 0 and 24 h. PaO(2)/FIO(2) rose significantly from 121+/-45 on ZEEP at 0 h, to 234+/-85 on PEEP of 12.8+/-3.7 cmH(2)O after 24 h. LIS did not change significantly (2.34+/-0.53 vs. 2.42+/-0.62). These variables behaved similarly in pulmonary and extrapulmonary ARDS, and in survivors and nonsurvivors. After 24 h only 18 patients (38%) still had a PaO(2)/FIO(2) of 200 or lower. Their mortality was similar to that in the remaining patients (61% vs. 53%). The use of PEEP improved oxygenation such that one-half of patients after 6 h, and most after 24 h did not fulfill AECC hypoxemia criteria of ARDS. However, LIS remained stable in the overall series. These results suggest that PEEP level should be taken into consideration for ARDS diagnosis.

Recruitment maneuvers in acute lung injury.

Maintaining optimal lung recruitment has a marked effect on the outcome of patients who suffer from ARDS. RMs superimposed on mechanical ventilation have the potential to recruit atelectatic lungs in the course of general anesthesia; however, the physiologic benefits are less evident in ARDS patients who are ventilated at low VT values and high PEEP levels. Currently, the following technical aspects warrant further investigation: optimal time (the first hours after intubation or the first days of ARDS), duration (from 15 seconds to 2 minutes), mode (continuous positive end-expiratory pressure or pressure controlled ventilation with high PEEP), and type of patients (pulmonary versus extrapulmonary ARDS). Before the routine implementation of RMs to recruit the lungs fully in ARDS patients, clinicians also need more information on side effects and contraindications. Although RMs are transient, they may be associated with complications such as hypotension, bradycardia, and barotrauma. Moreover, further studies are needed to compare the efficacy of periodic high-pressure RMs that are superimposed on mechanical ventilation with ventilation using high PEEP levels and low VT values without RMs in patients who have early ARDS after initial hemodynamic stabilization.

Acute remodeling of parenchyma in pulmonary and extrapulmonary ARDS. An autopsy study of collagen-elastic system fibers.

This study aimed at evaluating acute pulmonary remodeling, focusing on alterations of fibers of the collagenous and elastic systems in ARDS in the exudative phase according to the etiology of the disease. ARDS patients (n = 23), who died in our institution between 1989 and 1997, were retrospectively studied. Ten patients who died in accidents, without any pathological changes in the lung, and ten patients with Congestive Heart Failure (CHF), submitted to mechanical ventilation, were used as control groups. Histological slides were sampled from the autopsied lungs and stained by the Picrosirius and Weigert's resorcin-fuchsin methods. The fiber content of the collagenous and elastic systems of the alveolar septum was measured by image analysis. All patients were in the early ARDS phase (n = 23), 10 pulmonary and 13 extra-pulmonary diseases. Collagen content was greater in pulmonary (1.23+/-0.27) than in extra-pulmonary (0.92+/-0.39) ARDS in the early phase of the disease (p = 0.05). No differences were observed concerning the elastic fibers' content. Extracellular matrix (ECM) remodeling occurs early in the development of acute lung injury and appears to depend on the site of initial insult (pulmonary or extrapulmonary). The present study provides the basis for a prospective, controlled investigation.

Expiratory pressure-volume curves in pulmonary and extrapulmonary ARDS

Expiratory pressure-volume curves in pulmonary and extrapulmonary ARDS

Morphometric Differences in Pulmonary Lesions in Primary and Secondary ARDSA Preliminary Study in Autopsies

The present study was undertaken in order to describe the morphological differences between pulmonary lesions in acute respiratory distress syndrome originating from direct pulmonary injury (ARDSp) and those originating from extrapulmonary injury (ARDSexp). We investigated a total of 38 ARDS-patients (27 males) ranging in age from 19 to 75 years, classified according to underlying disease in pulmonary (ARDSp) and extrapulmonary disease (ARDSexp). The extent of acute diffuse alveolar damage was assessed morphometrically on histologic gross sections in the upper and lower lobes of one lung. The lesions showed quantitative differences in extent and distribution according to underlying disease (primary pulmonary or secondary involvement). In pulmonary ARDS, a predominance of alveolar collapse (16.6%+/-12.3% versus 10.3%+/-11.9%, p = 0,03), fibrinous exudate (1.7%+/-3.2% versus 0.4%+/-1.1%, p = 0.01) and alveolar wall edema (11.2%+/-7.4% versus 6.6%+/-4.4%, p = 0,05) were found compared to extrapulmonary ARDS. We conclude that the morphology of acute diffuse alveolar damage (DAD) is mainly determined by underlying disease (pulmonary ARDS or extrapulmonary ARDS) differing in quantitative terms within the lung. Physiological, radiographic and respiratory system mechanics differences described in ARDSp and ARDSexp may therefore be due to morphometric differences in pulmonary lesions.

The effects of recruitment maneuver on oxygenation in primary and secondary adult respiratory distress syndrome

Recruitment maneuvers (RM), as an adjunt to mechanical ventilation, have been shown to be capable of reopening collapsed alveolar units in ARDS, providing better ventilatory parameters and improvement in oxygenation. The aim of our study is to investigate and to compare the response of patients with pulmonary and extrapulmonary ARDS to recruitment maneuver.

Oxygenation response to prone positioning in pulmonary and extrapulmonary ARDS

Oxygenation response to prone positioning in pulmonary and extrapulmonary ARDS