Summary
Autopsy studies show that IA is among the most commonly missed diagnoses in critically ill patients. And, because of lack of unequivocal diagnostic criteria, a timely diagnosis remains ...challenging. We investigate the epidemiology of and the clinical risk factors for IA in critically ill patients. We conducted a retrospective, observational study of all consecutive ICU patients with evidence of IA in the postmortem examination. During the period of the study (25 years), 893 postmortem examinations were performed in the ICU. Twenty‐five patients (2.8%) were diagnosed with IA in autopsy. Only ten (40%) were classified as IA ante‐mortem, based on the initiation of antifungal treatment. The most common comorbid conditions were corticosteroid treatment (n = 14, 56%), chronic obstructive pulmonary disease (COPD) (n = 11, 44%), immunosuppression (n = 6, 24%) and haematological malignancy (n = 5, 20%). Twenty‐three patients (92%) had three or more risk factors for IA. Critically ill patients with pulmonary infiltrates, treated with high doses intravenous corticosteroids (even for a short period of time), particularly COPD patients who developed worsening respiratory insufficiency despite appropriate treatment were at the highest risk of IA.
Abstract Purpose The main objective of study was to evaluate the outcome of patients who require reintubation after elective extubation. Materials and Methods This is an observational, prospective ...cohort study including mechanically ventilated patients who passed successfully a spontaneous breathing trial. Patients were observed for 48 hours after extubation. During this time, reintubation or use of noninvasive positive pressure ventilation was considered as a failure. Reintubated patients were followed after the reintubation to register complications and outcome. Results A total of 1,152 extubated patients were included in the analysis. Three hundred thirty-six patients (29%) met the criteria for extubation failure. Extubation failure was independently associated with mortality (odds ratio, 3.29; 95% confidence interval, 2.19-4.93). One hundred eighty patients (16% of overall cohort) required reintubation within 48 hours after extubation. Median time from extubation to reintubation was 13 hours (interquartile range, 6-24 hours). Reintubation was independently associated with mortality (odds ratio, 5.18; 95% confidence interval, 3.38-7.94; P < .001). Higher mortality of reintubated patients was due to the development of complications after the reintubation. Conclusions In a large cohort of scheduled extubated patients, one third of patients developed extubation failure, of whom half needed reintubation. Reintubation was associated with increased mortality due to the development of new complications after reintubation.
Background
Extubation failure is associated with increased morbidity and mortality, but cannot be safely predicted or avoided. High-flow nasal cannula (HFNC) prevents postextubation respiratory ...failure in low-risk patients.
Objective
To demonstrate that HFNC reduces postextubation respiratory failure in high-risk non-hypercapnic patients compared with conventional oxygen.
Methods
Randomized, controlled multicenter trial in patients who passed a spontaneous breathing trial. We enrolled patients meeting criteria for high-risk of failure to randomly receive HFNC or conventional oxygen for 24 h after extubation. Primary outcome was respiratory failure within 72-h postextubation. Secondary outcomes were reintubation, intensive care unit (ICU) and hospital lengths of stay, and mortality. Statistical analysis included multiple logistic regression models.
Results
The study was stopped due to low recruitment after 155 patients were enrolled (78 received high-flow and 77 received conventional oxygen). Groups were similar at enrollment, and all patients tolerated 24-h HFNC. Postextubation respiratory failure developed in 16 (20%) HFNC patients and in 21 (27%) conventional patients OR 0.69 (0.31–1.54),
p
= 0.2. Reintubation was needed in 9 (11%) HFNC patients and in 12 (16%) conventional patients OR 0.71 (0.25–1.95),
p
= 0.5. No difference was found in ICU or hospital length of stay, or mortality. Logistic regression models suggested HFNC OR 0.43 (0.18–0.99),
p
= 0.04 and cancer OR 2.87 (1.04–7.91),
p
= 0.04 may be independently associated with postextubation respiratory failure.
Conclusion
Our study is inconclusive as to a potential benefit of HFNC over conventional oxygen to prevent occurrence of respiratory failure in non-hypercapnic patients at high risk for extubation failure.
Registered at Clinicaltrials.gov NCT01820507.
Diffuse alveolar damage is the histological hallmark of acute respiratory distress syndrome (ARDS). However, the chronology of histological lesions is not well established. We aimed to determine the ...time to onset of exudative or proliferative changes and end-stage fibrosis in ARDS.
We analysed all patients who died between Jan 1, 1991, and Dec 31, 2010, in the intensive-care unit at the Hospital Universitario de Getafe, Madrid, Spain, and who had a clinical autopsy. Patients had to have clinical criteria for ARDS at time of death and histological features of diffuse alveolar damage at autopsy examination. Capillary congestion and intra-alveolar oedema characterised the exudative phase whereas proliferation of alveolar cell type 2 or fibroblasts, or fibrosis characterised the proliferative phase.
We analysed 159 patients. The prevalence of exudative changes decreased over time, being reported in 74 (90%) of 82 patients with ARDS of less than 1 week duration, 40 (74%) of 54 patients with disease of 1-3 week duration, and only four (17%) of 23 patients with disease of longer than 3 weeks' duration (p<0·0001). The incidence of proliferative changes increased over time, and was reported in 44 (54%) of 82 patients with ARDS of less than 1-week duration, 42 (78%) of 54 patients with disease duration of 1-3 weeks, and 23 (100%) of 23 patients with disease duration longer than 3 weeks (p<0·0001). Fibrosis was noted in three (4%) of 82 patients with disease of less than 1 week duration, 13 (24%) of 54 patients with disease of 1-3-weeks' duration, and 14 (61%) of 23 patients with disease longer than 3-week duration (p<0·0001). Fibrosis was more frequent in ARDS of pulmonary origin than in that of extrapulmonary origin.
Histological features of the lungs were related to duration of ARDS. Within the first week of evolution, exudative changes were predominant and fibrosis was rarely noted. Beyond the third week of evolution, proliferative changes were noted in all patients and fibrosis in two-thirds of them. Treatments with a potential effect on inflammation or fibrosis, or both, should probably focus on the first week after the onset of ARDS.
None.
Baseline characteristics and management have changed over time in patients requiring mechanical ventilation; however, the impact of these changes on patient outcomes is unclear.
To estimate whether ...mortality in mechanically ventilated patients has changed over time.
Prospective cohort studies conducted in 1998, 2004, and 2010, including patients receiving mechanical ventilation for more than 12 hours in a 1-month period, from 927 units in 40 countries. To examine effects over time on mortality in intensive care units, we performed generalized estimating equation models.
We included 18,302 patients. The reasons for initiating mechanical ventilation varied significantly among cohorts. Ventilatory management changed over time (P < 0.001), with increased use of noninvasive positive-pressure ventilation (5% in 1998 to 14% in 2010), a decrease in tidal volume (mean 8.8 ml/kg actual body weight SD = 2.1 in 1998 to 6.9 ml/kg SD = 1.9 in 2010), and an increase in applied positive end-expiratory pressure (mean 4.2 cm H2O SD = 3.8 in 1998 to 7.0 cm of H2O SD = 3.0 in 2010). Crude mortality in the intensive care unit decreased in 2010 compared with 1998 (28 versus 31%; odds ratio, 0.87; 95% confidence interval, 0.80-0.94), despite a similar complication rate. Hospital mortality decreased similarly. After adjusting for baseline and management variables, this difference remained significant (odds ratio, 0.78; 95% confidence interval, 0.67-0.92).
Patient characteristics and ventilation practices have changed over time, and outcomes of mechanically ventilated patients have improved. Clinical trials registered with www.clinicaltrials.gov (NCT01093482).
A new classification of patients based on the duration of liberation of mechanical ventilation has been proposed.
To analyze outcomes based on the new weaning classification in a cohort of ...mechanically ventilated patients.
Secondary analysis included 2,714 patients who were weaned and underwent scheduled extubation from a cohort of 4,968 adult patients mechanically ventilated for more than 12 hours.
Patients were classified according to a new weaning classification: 1,502 patients (55%) as simple weaning,1,058 patients (39%) as difficult weaning, and 154 (6%) as prolonged weaning.Variables associated with prolonged weaning(.7d)were: severity at admission (odds ratio OR per unit of Simplified Acute Physiology Score II, 1.01; 95% confidence interval CI, 1.001–1.02), duration of mechanical ventilation before first attempt of weaning (OR per day, 1.10; 95% CI, 1.06–1.13), chronic pulmonary disease other than chronic obstructive pulmonary disease (OR,13.23; 95% CI, 3.44–51.05), pneumonia as the reason to start mechanical ventilation (OR, 1.82; 95% CI, 1.07–3.08), and level of positive end-expiratory pressure applied before weaning (OR per unit,1.09; 95% CI, 1.04–1.14). The prolonged weaning group had a nonsignificant trend toward a higher rate of reintubation (P ¼ 0.08),tracheostomy (P ¼ 0.15), and significantly longer length of stay and higher mortality in the intensive care unit (OR for death, 1.97;95%CI, 1.17–3.31). The adjusted probability of death remained constant until Day 7, at which point it increased to 12.1%.
To determine the incidence, risk factors, and outcome of barotrauma in a cohort of mechanically ventilated patients where limited tidal volumes and airway pressures were used.
Prospective cohort of ...361 intensive care units from 20 countries.
A total of 5183 patients mechanically ventilated for more than 12 h.
Baseline demographic data, primary indication for mechanical ventilation, daily ventilator settings, multiple-organ failure over the course of mechanical ventilation and outcome were collected. Barotrauma was present in 154 patients (2.9%). The incidence varied according to the reason for mechanical ventilation: 2.9% of patients with chronic obstructive pulmonary disease; 6.3% of patients with asthma; 10.0% of patients with chronic interstitial lung disease (ILD); 6.5% of patients with acute respiratory distress syndrome (ARDS); and 4.2% of patients with pneumonia. Patients with and without barotrauma did not differ in any ventilator parameter. Logistic regression analysis identified as factors independently associated with barotrauma: asthma RR 2.58 (1.05-6.50), ILD RR 4.23 (95%CI 1.78-10.03); ARDS as primary reason for mechanical ventilation RR 2.70 (95%CI 1.55-4.70); and ARDS as a complication during the course of mechanical ventilation RR 2.53 (95%CI 1.40-4.57). Case-control analysis showed increased mortality in patients with barotrauma (51.4 vs 39.2%; p=0.04) and prolonged ICU stay.
In a cohort of patients in whom airway pressures and tidal volume are limited, barotrauma is more likely in patients ventilated due to underlying lung disease (acute or chronic). Barotrauma was also associated with a significant increase in the ICU length of stay and mortality.
Recent literature in mechanical ventilation includes strong evidence from randomized trials. Little information is available regarding the influence of these trials on usual clinical practice.
To ...describe current mechanical ventilation practices and to assess the influence of interval randomized trials when compared with findings from a 1998 cohort.
A prospective international observational cohort study, with a nested comparative study performed in 349 intensive care units in 23 countries. We enrolled 4,968 consecutive patients receiving mechanical ventilation over a 1-month period. We recorded demographics and daily data related to mechanical ventilation for the duration of ventilation. We systematically reviewed the literature and developed 11 practice-change hypotheses for the comparative cohort study before seeing these results. In assessing practice changes, we only compared data from the 107 intensive care units (1,675 patients) that also participated in the 1998 cohort (1,383 patients).
In 2004 compared with 1998, the use of noninvasive ventilation increased (11.1 vs. 4.4%, P < 0.001). Among patients with acute respiratory distress syndrome, tidal volumes decreased (7.4 vs. 9.1 ml/kg, P < 0.001) and positive end-expiratory pressure levels increased slightly (8.7 vs. 7.7 cm H(2)O, P = 0.02). More patients were successfully extubated after their first attempt of spontaneous breathing (77 vs. 62%, P < 0.001). Use of synchronized intermittent mandatory ventilation fell dramatically (1.6 vs. 11%, P < 0.001). Observations confirmed 10 of our 11 practice-change hypotheses.
The strong concordance of predicted and observed practice changes suggests that randomized trial results have advanced mechanical ventilation practices internationally.
A single-center retrospective study initial recently identified ventilator settings as a major risk factor for the development of acute respiratory distress syndrome (ARDS) in mechanically ventilated ...patients who do not have ARDS from the outset. We tested this hypothesis in a larger sample of patients prospectively enrolled in a multicenter study on mechanical ventilation.
From a large international mechanical ventilation study database we identified patients who required mechanical ventilation for 48 h or more but did not have ARDS at the onset of mechanical ventilation. We extracted information on demographics, initial severity of illness, ventilator settings and major underlying ARDS risk factors. Primary outcome was development of ARDS after the onset of mechanical ventilation.
Of 3,261 mechanically ventilated patients who did not have ARDS at the outset 205 (6.2%) developed ARDS 48 h or more after the onset of mechanical ventilation. Multivariate logistic regression analysis adjusted for baseline patient characteristics (age, gender, Simplified Acute Physiology Score, hypoxemia) and underlying ARDS risk factors (sepsis, trauma, pneumonia) found the development of ARDS to be associated with the initial ventilator settings: high tidal volume (odds ratio 2.6 for tidal volume>700 ml), high peak airway pressure (odds ratio 1.6 for peak airway pressure>30 cmH2O), and high positive end-expiratory pressure (odds ratio 1.7 for end-expiratory pressure>5 cmH2O).
The association with the potentially injurious initial ventilator settings, in particular large tidal volumes, suggests that ARDS in mechanically ventilated patients is in part a preventable complication. This hypothesis needs to be tested in a prospective study.
Abstract Methods We studied patients requiring mechanical ventilation for more than 48 hours who died in the intensive care unit and whose bodies were autopsied. We evaluated 3 clinical definitions ...of ventilator-associated pneumonia: loose definition, defined as chest radiograph infiltrates and 2 of 3 clinical criteria (leukocytosis, fever, purulent respiratory secretions); rigorous definition, defined as chest radiograph infiltrates and all of the clinical criteria; and a clinical pulmonary infection score higher than 6 points. Sensitivity, specificity, and likelihood ratios were calculated by using pathology pattern as criterion standard. Results One hundred forty-two (56%) of the 253 patients included had histological criteria of pneumonia. Patients who met the clinical criteria of ventilator-associated pneumonia were 163 (64%) for the loose definition, 32 (13%) for the rigorous definition, and 109 (43%) for the clinical pulmonary infection score. The operative indexes (sensitivity and specificity) of each definition were as follows: loose definition, 64.8% and 36%; rigorous definition, 91% and 15.5%; and clinical pulmonary infection score higher than 6, 45.8% and 60.4%. The addition of microbiological data to the clinical definitions increased the specificity and decreased the sensitivity but not significantly. Conclusions Accuracy of 3 commonly used clinical definitions of ventilator-associated pneumonia was poor taking the autopsy findings as reference standard.
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