Application of a multiplex molecular pneumonia panel and real-world impact on antimicrobial stewardship among patients with hospital-acquired and ventilator-associated pneumonia in intensive care units.

BACKGROUND: The optimal timing for applying the BioFire FilmArray Pneumonia Panel (FAPP) in intensive care unit (ICU) patients with hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP) remains undefined, and there are limited data on its impact on antimicrobial stewardship. METHODS: This retrospective study was conducted at a referral hospital in Taiwan from November 2019 to October 2022. Adult ICU patients with HAP/VAP who underwent FAPP testing were enrolled. Patient data, FAPP results, conventional microbiological testing results, and the real-world impact of FAPP results on antimicrobial therapy adjustments were assessed. Logistic regression was used to determine the predictive factors for bacterial detection by FAPP. RESULTS: Among 592 respiratory specimens, including 564 (95.3%) endotracheal aspirate specimens, 19 (3.2%) expectorated sputum specimens and 9 (1.5%) bronchoalveolar lavage specimens, from 467 patients with HAP/VAP, FAPP testing yielded 368 (62.2%) positive results. Independent predictors for positive bacterial detection by FAPP included prolonged hospital stay (odds ratio [OR], 3.14), recent admissions (OR, 1.59), elevated C-reactive protein levels (OR, 1.85), Acute Physiology and Chronic Health Evaluation II scores (OR, 1.58), and septic shock (OR, 1.79). Approximately 50% of antimicrobial therapy for infections caused by Gram-negative bacteria and 58.4% for Gram-positive bacteria were adjusted or confirmed after obtaining FAPP results. CONCLUSIONS: This study identified several factors predicting bacterial detection by FAPP in critically ill patients with HAP/VAP. More than 50% real-world clinical practices were adjusted or confirmed based on the FAPP results. Clinical algorithms for the use of FAPP and antimicrobial stewardship guidelines may further enhance its benefits.

Clinical characteristics and treatment outcomes among the hospitalized elderly patients with COVID-19 during the late pandemic phase in central Taiwan.

BACKGROUND: There is a lack of information regarding outcomes of elderly patients hospitalized with COVID-19 following the widespread use of COVID-19 vaccines and antiviral agents. METHODS: A retrospective study was conducted between January and August 2022, enrolling patients aged 65 years or older. Patients were categorized into two groups: 'old' (65-79 years) and 'oldest-old' (80 years or more). Multivariate regression was employed to identify independent prognostic factors for in-hospital mortality. RESULTS: A total of 797 patients were enrolled, including 428 old and 369 oldest-old patients. In each subgroup, 66.6 % and 59.6 % of patients received at least one dose of the COVID-19 vaccine, respectively. Approximately 40 % of the patients received oral antiviral agents either before or upon hospital admission. A greater percentage of the oldest-old patients received remdesivir (53.4 % versus 39.7 %, p < 0.001), dexamethasone (49.3 % versus 36.7 %, p < 0.001), and tocilizumab (10.0 % versus 6.8 %, p < 0.001) than old patients. The mortality rate was comparable between the two age subgroups (14 % versus 15.2 %). Independent predictors of in-hospital mortality included disease severity and comorbidities such as end-stage renal disease (ESRD), cirrhosis, solid tumours, and haematologic malignancies. Ageing was not correlated with increased in-hospital mortality across all comorbidity subgroups. CONCLUSIONS: In the later stages of the pandemic, with widespread vaccination and advancements in COVID-19 treatments, outcomes for hospitalized elderly and oldest-old patients with COVID-19 have improved. The influence of age on in-hospital mortality has diminished, while comorbidities such as ESRD, cirrhosis, solid tumours, and hematologic malignancies have been associated with mortality.

Risk factors for prolonged mechanical ventilation in critically ill patients with influenza-related acute respiratory distress syndrome.

BACKGROUND: Patients with influenza-related acute respiratory distress syndrome (ARDS) are critically ill and require mechanical ventilation (MV) support. Prolonged mechanical ventilation (PMV) is often seen in these cases and the optimal management strategy is not established. This study aimed to investigate risk factors for PMV and factors related to weaning failure in these patients. METHODS: This retrospective cohort study was conducted by eight medical centers in Taiwan. All patients in the intensive care unit with virology-proven influenza-related ARDS requiring invasive MV from January 1 to March 31, 2016, were included. Demographic data, critical illness data and clinical outcomes were collected and analyzed. PMV is defined as mechanical ventilation use for more than 21 days. RESULTS: There were 263 patients with influenza-related ARDS requiring invasive MV enrolled during the study period. Seventy-eight patients had PMV. The final weaning rate was 68.8% during 60 days of observation. The mortality rate in PMV group was 39.7%. Risk factors for PMV were body mass index (BMI) > 25 (kg/m2) [odds ratio (OR) 2.087; 95% confidence interval (CI) 1.006-4.329], extracorporeal membrane oxygenation (ECMO) use (OR 6.181; 95% CI 2.338-16.336), combined bacterial pneumonia (OR 4.115; 95% CI 2.002-8.456) and neuromuscular blockade use over 48 h (OR 2.8; 95% CI 1.334-5.879). In addition, risk factors for weaning failure in PMV patients were ECMO (OR 5.05; 95% CI 1.75-14.58) use and bacteremia (OR 3.91; 95% CI 1.20-12.69). CONCLUSIONS: Patients with influenza-related ARDS and PMV have a high mortality rate. Risk factors for PMV include BMI > 25, ECMO use, combined bacterial pneumonia and neuromuscular blockade use over 48 h. In addition, ECMO use and bacteremia predict unsuccessful weaning in PMV patients.

High mortality of patients with severe pneumonia caused by respiratory syncytial virus, August 2021-June 2023, Taiwan.

Among the 14 patients with respiratory syncytial virus pneumonia, the majority (n = 8, 57.1 %) were older than 65 years and had health care-associated pneumonia (57.1 %). Over 70 % (n = 10) of them exhibited bacterial co-infection, with a high proportion (64.3 %) requiring mechanical ventilation. The hospital mortality rate was 50 %.

Prediction of methicillin-resistant Staphylococcus aureus and carbapenem-resistant Klebsiella pneumoniae from flagged blood cultures by combining rapid Sepsityper MALDI-TOF mass spectrometry with machine learning.

This study investigated combination of the Rapid Sepsityper Kit and a machine learning (ML)-based matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) approach for rapid prediction of methicillin-resistant Staphylococcus aureus (MRSA) and carbapenem-resistant Klebsiella pneumoniae (CRKP) from positive blood culture bottles. The study involved 461 patients with monomicrobial bloodstream infections. Species identification was performed using the conventional MALDI-TOF MS Biotyper system and the Rapid Sepsityper protocol. The data underwent preprocessing steps, and ML models were trained using preprocessed MALDI-TOF data and corresponding labels. The interpretability of the model was enhanced using SHapely Additive exPlanations values to identify significant features. In total, 44 S. aureus isolates comprising 406 MALDI-TOF MS files and 126 K. pneumoniae isolates comprising 1249 MALDI-TOF MS files were evaluated. This study demonstrated the feasibility of predicting MRSA among S. aureus and CRKP among K. pneumoniae isolates using MALDI-TOF MS and Sepsityper. Accuracy, area under the receiver operating characteristic curve, and F1 score for MRSA/methicillin-susceptible S. aureus were 0.875, 0.898 and 0.904, respectively; for CRKP/carbapenem-susceptible K. pneumoniae, these values were 0.766, 0.828 and 0.795, respectively. In conclusion, the novel ML-based MALDI-TOF MS approach enables rapid identification of MRSA and CRKP from flagged blood cultures within 1 h. This enables earlier initiation of targeted antimicrobial therapy, reducing deaths due to sepsis. The favourable performance and reduced turnaround time of this method suggest its potential as a rapid detection strategy in clinical microbiology laboratories, ultimately improving patient outcomes.

Direct prediction of carbapenem-resistant, carbapenemase-producing, and colistin-resistant Klebsiella pneumoniae isolates from routine MALDI-TOF mass spectra using machine learning and outcome evaluation.

The objective of this study was to develop a rapid prediction method for carbapenem-resistant Klebsiella pneumoniae (CRKP) and colistin-resistant K. pneumoniae (ColRKP) based on routine MALDI-TOF mass spectrometry (MS) results in order to formulate a suitable and rapid treatment strategy. A total of 830 CRKP and 1462 carbapenem-susceptible K. pneumoniae (CSKP) isolates were collected; 54 ColRKP isolates and 1592 colistin-intermediate K. pneumoniae (ColIKP) isolates were also included. Routine MALDI-TOF MS, antimicrobial susceptibility testing, NG-Test CARBA 5, and resistance gene detection were followed by machine learning (ML). Using the ML model, the accuracy and area under the curve for differentiating CRKP and CSKP were 0.8869 and 0.9551, respectively, and those for ColRKP and ColIKP were 0.8361 and 0.8447, respectively. The most important MS features of CRKP and ColRKP were m/z 4520-4529 and m/z 4170-4179, respectively. Of the CRKP isolates, MS m/z 4520-4529 was a potential biomarker for distinguishing KPC from OXA, NDM, IMP, and VIM. Of the 34 patients who received preliminary CRKP ML prediction results (by texting), 24 (70.6%) were confirmed to have CRKP infection. The mortality rate was lower in patients who received antibiotic regimen adjustment based on the preliminary ML prediction (4/14, 28.6%). In conclusion, the proposed model can provide rapid results for differentiating CRKP and CSKP, as well as ColRKP and ColIKP. The combination of ML-based CRKP with preliminary reporting of results can help physicians alter the regimen approximately 24 h earlier, resulting in improved survival of patients with timely antibiotic intervention.

Using real-time visualization system for data-driven decision support to achieve lung protective strategy: a retrospective observational study.

BACKGROUND: Although lung protective strategy and adjunctive intervention are associated with improved survival in patients with acute respiratory distress syndrome (ARDS), the implementation of effective therapies remains low. This study aimed to evaluate whether the use of business intelligence (BI) for real-time data visualization is associated with an improvement in lung protective strategy and adjunctive therapy. METHODS: A retrospective observational cohort study was conducted on patients with ARDS admitted between September 2020 and June 2021 at two intensive care units (ICUs) of a tertiary referral hospital in Taiwan. BI was imported for data visualization and integration to assist in clinical decision in one of the ICUs. The primary outcomes were the implementation of low tidal volume ventilation (defined as tidal volume/predicted body weight ≤ 8 mL/kg) within 24 h from ARDS onset. The secondary outcomes included ICU and hospital mortality rates. RESULTS: Among the 1201 patients admitted to the ICUs during the study period, 148 (12.3%) fulfilled the ARDS criteria, with 86 patients in the BI-assisted group and 62 patients in the standard-of-care (SOC) group. Disease severity was similar between the two groups. The application of low tidal volume ventilation strategy was significantly improved in the BI-assisted group compared with that in the SOC group (79.1% vs. 61.3%, p = 0.018). Despite their ARDS and disease severity, the BI-assisted group tended to achieve low tidal volume ventilation. The ICU and hospital mortality were lower in the BI-assisted group. CONCLUSIONS: The use of real-time visualization system for data-driven decision support was associated with significantly improved compliance to low tidal volume ventilation strategy, which enhanced the outcomes of patients with ARDS in the ICU.

Clinical outcome of nosocomial pneumonia caused by Carbapenem-resistant gram-negative bacteria in critically ill patients: a multicenter retrospective observational study.

Nosocomial pneumonia caused by carbapenem-resistant gram-negative bacteria (CRGNB) is a growing threat due to the limited therapeutic choices and high mortality rate. The aim of this study was to evaluate the prognostic factors for mortality in patients with nosocomial pneumonia caused by CRGNB and the impact of colistin-based therapy on the outcomes of intensive care unit (ICU) patients. We conducted a retrospective study of the ICUs in five tertiary teaching hospitals in Taiwan. Patients with nosocomial pneumonia caused by CRGNB from January 2016 to December 2016 were included. Prognostic factors for mortality were analyzed using multivariate logistic regression. The influence of colistin-based therapy on mortality and clinical and microbiological outcomes were evaluated in subgroups using different severity stratification criteria. A total of 690 patients were enrolled in the study, with an in-hospital mortality of 46.1%. The most common CRGNB pathogens were Acinetobacter baumannii (78.7%) and Pseudomonas aeruginosa (13.0%). Significant predictors (odds ratio and 95% confidence interval) of mortality from multivariate analysis were a length of hospital stay (LOS) prior to pneumonia of longer than 9 days (2.18, 1.53-3.10), a sequential organ failure assessment (SOFA) score of more than 7 (2.36, 1.65-3.37), supportive care with vasopressor therapy (3.21, 2.26-4.56), and escalation of antimicrobial therapy (0.71, 0.50-0.99). There were no significant differences between the colistin-based therapy in the deceased and survival groups (42.1% vs. 42.7%, p = 0.873). In the subgroup analysis, patients with multiple organ involvement (> 2 organs) or higher SOFA score (> 7) receiving colistin-based therapy had better survival outcomes. Prolonged LOS prior to pneumonia onset, high SOFA score, vasopressor requirement, and timely escalation of antimicrobial therapy were predictors for mortality in critically ill patients with nosocomial CRGNB pneumonia. Colistin-based therapy was associated with better survival outcomes in subgroups of patients with a SOFA score of more than 7 and multiple organ involvement.

Targeting glycolysis in Th2 cells by pterostilbene attenuates clinical severities in an asthmatic mouse model and IL-4 production in peripheral blood from asthmatic patients.

Asthma, a major non-communicable disease, affects both adults and children and is associated with high morbidity compared with other chronic diseases. The glycolysis-associated activation of type 2 helper T (Th2) cells is the critical immunopathological mechanism involved in asthma deterioration. Long-term use of steroids as a medical treatment for asthma induces side effects and resistance. Pterostilbene (PS), a stilbenoid compound found in blueberry and vines, exhibits antihyperglycemic and anti-inflammatory properties. Thus, we hypothesized that the modulation of T cell immunity by PS may be an applicable intervention to treat asthma. Airway hyperresponsiveness, interleukin (IL)-4 and IL-13 levels, IgE, IgG, pulmonary infiltrated monocytes and eosinophils, and mucosubstances were measured in house dust mite (HDM)-induced asthmatic mice under PS treatment. Bioenergetic metabolism, PI3K-mTOR signalling, GATA3 expression and histone acetylation in PS-treated Th2 cells were investigated. PS improved HDM-induced pulmonary allergic airway inflammation by inhibiting Th2 cell and eosinophil accumulation in HDM asthmatic mice both in the preventive and therapeutic models. Targeting glycolysis resulted in IL-4 inhibition via the downregulation of mTOR, GATA3 and histone acetylation in PS-treated Th2 cells. Glucose supplementation reversed the inhibitory effect of PS on Th2 cells in vitro. Adoptive transfer with glucose-treated Th2 cells enhanced Th2 activation and eosinophilic accumulation in PS-treated asthmatic mice. Furthermore, PS significantly inhibited IL-4 production of CD4+ T cells from the peripheral blood mononuclear cells of patients with asthma. PS attenuates HDM-induced asthma via the inhibition of the Glut1/mTOR/GATA3 axis in Th2 cells, which supports the potential pharmaceutical application of PS treatment for asthma.

Comparison of prone positioning and extracorporeal membrane oxygenation in acute respiratory distress syndrome: A multicenter cohort study and propensity-matched analysis.

BACKGROUND/PURPOSE: Both prone positioning and extracorporeal membrane oxygenation (ECMO) are used as rescue therapies for severe hypoxemia in patients with acute respiratory distress syndrome (ARDS). This study compared outcomes between patients with severe influenza pneumonia-related ARDS who received prone positioning and those who received ECMO. METHODS: This retrospective cohort study included eight tertiary referral centers in Taiwan. All patients who were diagnosed as having influenza pneumonia-related severe ARDS were enrolled between January and March 2016. We collected their demographic data and prone positioning and ECMO outcomes from medical records. RESULTS: In total, 263 patients diagnosed as having ARDS were included, and 65 and 53 of them received prone positioning and ECMO, respectively. The baseline PaO2/FiO2 ratio, Acute Physiology and Chronic Health Evaluation II score and Sequential Organ Failure Assessment score did not significantly differ between the two groups. The 60-day mortality rate was significantly higher in the ECMO group than in the prone positioning group (60% vs. 28%, p = 0.001). A significantly higher mortality rate was still observed in the ECMO group after propensity score matching (59% vs. 36%, p = 0.033). In the multivariate Cox regression analysis, usage of prone positioning or ECMO was the single independent predictor for 60-day mortality (hazard ratio: 2.177, p = 0.034). CONCLUSION: While the patients receiving prone positioning had better outcome, the causality between prone positioning and the prognosis is unknown. However, the current data suggested that patients with influenza-related ARDS may receive prone positioning before ECMO support.

Polysomnography Is an Important Method for Diagnosing Pediatric Sleep Problems: Experience of One Children's Hospital.

In this study, we collected and analyzed polysomnography (PSG) data to investigate the value of PSG in diagnosing sleep problems in children. The results of PSG studies of children (<18 years old) with sleep problems conducted from April 2015 to May 2017 at a children's hospital in Taiwan were collected and analyzed retrospectively. Data for 310 patients (209 males and 101 females) who underwent PSG were collected. The final diagnoses were as follows: obstructive sleep apnea in 159 (51.3%), snoring in 81 (26.4%), limb movement sleep disorder in 25 (8.1%), hypersomnias in 12 (3.9%), central apnea in 8 (2.9%), enuresis in 7 (2.3%), bruxism in 5 (1.6%), sleep terrors in 5 (1.6%), narcolepsy in 3 (1.0%), sleep seizures in 3 (1.0%), sleep walking in 1 (0.3%), and insomnia in 1 (0.3%). PSG may help detect significant sleep-related problems in children and is useful for making therapeutic decisions regarding children. Obstructive sleep apnea syndrome (OSAS) was the primary sleep problem for most of the children (51.3%); however, only 7.4% of them underwent surgery for OSAS. We therefore suggest that children with sleep problems should undergo PSG.

Renal Replacement Therapy in Patients with Influenza Pneumonia Related Acute Respiratory Distress Syndrome.

Acute kidney injury (AKI) requiring renal replacement therapy (RRT) increases the mortality of acute respiratory distress syndrome (ARDS) patients. The aim of this study was to investigate the outcomes and predictors of RRT in patients with influenza pneumonia-related ARDS. This retrospective cohort study includes patients from eight tertiary referral centers in Taiwan between January and March 2016, and all 282 patients with influenza pneumonia-related ARDS were enrolled. Thirty-four patients suffered from AKI requiring RRT, while 16 patients had underlying end stage renal disease (ESRD). The 30- and 60-day mortality rates were significantly higher in patients with AKI requiring RRT compared with those not requiring RRT (50.0% vs. 19.8%, p value < 0.001; 58.8% vs. 27.2%, p value = 0.001, respectively), but the patients with ESRD had no significant difference in mortality (12.5% vs. 19.8%, p value = 0.744; 31.3% vs. 27.2%, p value = 0.773, respectively). The predictors for AKI requiring RRT included underlying chronic liver disease and C-reactive protein. The mortality predictors for patients with AKI requiring RRT included the pneumonia severity index, tidal volume, and continuous renal replacement therapy. In this study, patients with influenza pneumonia-related ARDS with AKI requiring RRT had significantly higher mortality compared with other patients.

[Applying Team Resource Management to Reduce the Urinary Catheter Usage Rate in Our Intensive Care Unit].

BACKGROUND & PROBLEMS: According to the literature, 74%-84% of patients in adult critical care units have an indwelling catheter. The majority of medical and healthcare infections are urinary tract infections, which are related to urinary catheter usage. Furthermore, critical infections may cause bacteremia, which increases the risk of mortality. Prior to this project, over three-quarters (78.7%) of patients in our unit used a urinary catheter, which is a rate that is higher than all other intensive care units of our hospital's internal medicine department. Due to Foley placement, removal and care of catheters requires collaboration of teamwork. Thus, the concept of team resource management may be applied to improve the situation. PURPOSE: The aim of this study was to reduce the urinary catheter usage rate in our intensive care unit to less than 69.3%. RESOLUTIONS: This project summarized the reasons for the high catheter usage rate in this unit on 2017/1/3 and implemented several approaches to improve the situation from 2017/2/1 to 2017/6/30. These approaches included affixing reminder labels to indwelling catheters, using an ultrasound bladder scanner as a substitute for intermittent catheterization, evaluating indwelling catheters, establishing flow planning for post-catheter removal, holding cross-team meetings, and adopting a reward system. During the improvement period, we held collaborative conference meetings weekly to discuss solutions, evaluate end-of-the-month progress, and set reward policies. RESULTS: We lowered the average urinary catheter usage rate from 78.7% on 2017/3/1 to 57.8% on 2017/6/30, achieving a 26.5% reduction in catheter usage. CONCLUSIONS: This project both effectively reduced the unnecessary use of urinary catheters and significantly strengthened team spirit in our unit, thus improving the quality of medical care provided.

Risk factor analysis of nosocomial lower respiratory tract infection in influenza-related acute respiratory distress syndrome.

BACKGROUND: Patients with severe influenza-related acute respiratory distress syndrome (ARDS) have high morbidity and mortality. Moreover, nosocomial lower respiratory tract infection (NLRTI) complicates their clinical management and possibly worsens their outcomes. This study aimed to explore the clinical features and impact of NLRTI in patients with severe influenza-related ARDS. METHODS: This was an institutional review board approved, retrospective, observational study conducted in eight medical centers in Taiwan. From January 1 to March 31 in 2016, subjects were enrolled from intensive care units (ICUs) with virology-proven influenza pneumonia, while all of those patients with ARDS requiring invasive mechanical ventilation and without bacterial community-acquired pneumonia (CAP) were analyzed. Baseline characteristics, critical-illness data and clinical outcomes were recorded. RESULTS: Among the 316 screened patients with severe influenza pneumonia, 250 with acute respiratory failure requiring intubation met the criteria of ARDS, without having bacterial CAP. Among them, 72 patients developed NLRTI. The independent risk factors for NLRTI included immunosuppressant use before influenza infection [odds ratio (OR), 5.669; 95% confidence interval (CI), 1.770-18.154], extracorporeal membrane oxygenation (ECMO) use after ARDS (OR, 2.440; 95% CI, 1.214-4.904) and larger corticosteroid dosage after ARDS (OR, 1.209; 95% CI, 1.038-1.407). Patients with NLRTI had higher in-hospital mortality and longer ICU stay, hospitalization and duration on mechanical ventilation. CONCLUSION: We found that immunosuppressant use before influenza infection, ECMO use, and larger steroid dosage after ARDS independently predict NLRTI in influenza-related ARDS. Moreover, NLRTI results in poorer outcomes in patients with severe influenza.The reviews of this paper are available via the supplemental material section.

Impact of corticosteroid treatment on clinical outcomes of influenza-associated ARDS: a nationwide multicenter study.

BACKGROUND: Corticosteroid treatment has been widely used in the treatment of septic shock, influenza, and ARDS, although some previous studies discourage its use in severe influenza patients. This multicenter retrospective cohort study conducted in the intensive care units (ICUs) of eight medical centers across Taiwan aims to determine the real-world status of corticosteroid treatment in patients with influenza-associated acute respiratory distress syndrome (ARDS) and its impact on clinical outcomes. Between October 2015 and March 2016, consecutive ICU patients with virology-proven influenza infections who fulfilled ARDS and received invasive mechanical ventilation were enrolled. The impact of early corticosteroid treatment (≥ 200 mg hydrocortisone equivalent dose within 3 days after ICU admission, determined by a sensitivity analysis) on hospital mortality (the primary outcome) was assessed by multivariable logistic regression analysis, and further confirmed in a propensity score-matched cohort. RESULTS: Among the 241 patients with influenza-associated ARDS, 85 (35.3%) patients receiving early corticosteroid treatment had similar baseline characteristics, but a significantly higher hospital mortality rate than those without early corticosteroid treatment [43.5% (37/85) vs. 19.2% (30/156), p < 0.001]. Early corticosteroid treatment was independently associated with increased hospital mortality in overall patients [adjusted odds ratio (95% CI) = 5.02 (2.39-10.54), p < 0.001] and in all subgroups. Earlier treatment and higher dosing were associated with higher hospital mortality. Early corticosteroid treatment was associated with a significantly increased odds of subsequent bacteremia [adjusted odds ratio (95% CI) = 2.37 (1.01-5.56)]. The analyses using a propensity score-matched cohort showed consistent results. CONCLUSIONS: Early corticosteroid treatment was associated with a significantly increased hospital mortality in adult patients with influenza-associated ARDS. Earlier treatment and higher dosing were associated with higher hospital mortality. Clinicians should be cautious while using corticosteroid treatment in this patient group.

Using a machine learning approach to predict mortality in critically ill influenza patients: a cross-sectional retrospective multicentre study in Taiwan.

OBJECTIVES: Current mortality prediction models used in the intensive care unit (ICU) have a limited role for specific diseases such as influenza, and we aimed to establish an explainable machine learning (ML) model for predicting mortality in critically ill influenza patients using a real-world severe influenza data set. STUDY DESIGN: A cross-sectional retrospective multicentre study in Taiwan SETTING: Eight medical centres in Taiwan. PARTICIPANTS: A total of 336 patients requiring ICU-admission for virology-proven influenza at eight hospitals during an influenza epidemic between October 2015 and March 2016. PRIMARY AND SECONDARY OUTCOME MEASURES: We employed extreme gradient boosting (XGBoost) to establish the prediction model, compared the performance with logistic regression (LR) and random forest (RF), demonstrated the feature importance categorised by clinical domains, and used SHapley Additive exPlanations (SHAP) for visualised interpretation. RESULTS: The data set contained 76 features of the 336 patients with severe influenza. The severity was apparently high, as shown by the high Acute Physiology and Chronic Health Evaluation II score (22, 17 to 29) and pneumonia severity index score (118, 88 to 151). XGBoost model (area under the curve (AUC): 0.842; 95% CI 0.749 to 0.928) outperformed RF (AUC: 0.809; 95% CI 0.629 to 0.891) and LR (AUC: 0.701; 95% CI 0.573 to 0.825) for predicting 30-day mortality. To give clinicians an intuitive understanding of feature exploitation, we stratified features by the clinical domain. The cumulative feature importance in the fluid balance domain, ventilation domain, laboratory data domain, demographic and symptom domain, management domain and severity score domain was 0.253, 0.113, 0.177, 0.140, 0.152 and 0.165, respectively. We further used SHAP plots to illustrate associations between features and 30-day mortality in critically ill influenza patients. CONCLUSIONS: We used a real-world data set and applied an ML approach, mainly XGBoost, to establish a practical and explainable mortality prediction model in critically ill influenza patients.

Air Pollutants Are Associated With Obstructive Sleep Apnea Severity in Non-Rapid Eye Movement Sleep.

STUDY OBJECTIVES: The relationship between seasonal variation of obstructive sleep apnea and ambient temperature and pollutants has been inconsistent in previous studies. It is also unknown whether the seasonal variation in apnea-hypopnea index influences continuous positive airway pressure treatment dose. This study aims to examine the seasonality of obstructive sleep apnea and continuous positive airway pressure treatment, and the association between air pollutants and apnea-hypopnea index in adults with different sleep apnea severity during different sleep stages. METHODS: Polysomnography of 5,413 patients referred to one sleep center during 2008-2015 were examined retrospectively. Ambient conditions and air pollutants levels were collected from the official air condition surveillance database. Cosinor analysis was used to examine seasonal variances. The general linear model was used to examine associations between air conditions and apnea-hypopnea index adjusted for seasonality. Models for apnea-hypopnea index in different sleep stages, sex groups, and obstructive sleep apnea severity groups were analyzed separately. RESULTS: Seasonal variations for continuous positive airway pressure treatment were not significant. Particulate matter less than or equal to 10 µm, ozone, sulfur dioxide, and relative humidity were associated with apnea-hypopnea index only in patients with severe obstructive sleep apnea. The association was significant only in non-rapid eye movement sleep. CONCLUSIONS: An adjustment for continuous positive airway treatment dose by season is not warranted. Protection for air pollutant-vulnerable groups should be provided. The exact mechanism of the associations between apnea-hypopnea index and air conditions only in non-rapid eye movement sleep must be clarified.

First tidal volume greater than 8 mL/kg is associated with increased mortality in complicated influenza infection with acute respiratory distress syndrome.

BACKGROUNDS: Severe influenza infection causes substantial morbidity and mortality worldwide and remains an important threat to global health. This study addressed factors related to treatment outcomes in subjects of complicated influenza infection with acute respiratory distress syndrome (ARDS) during the Taiwan epidemic in the Spring of 2016. METHODS: This is a retrospective study conducted by Taiwan Severe Influenza Research Consortium (TSIRC), including eight tertiary referral medical centers. Patients with virology-proven influenza infection admitted to intensive care unit (ICU) between January and March 2016 were included for analysis. RESULTS: We identified 263 patients with complicated influenza infection who fulfilled ARDS criteria; the mean age was 59.8 ± 14.6 (years), and 66.1% (166/263) were male. Type A influenza (77.9%, 205/263) virus was the main pathogen during this epidemic. The 30-day mortality rate was 23.2% (61/263). The mean tidal volume (VT) in the first three days after intubation was greater than 8 mL/kg of predicted body weight (PBW). Patients whose first measured VT was >8 mL/kg PBW had an increased 30-day mortality (p = 0.04, log-rank test). In a multivariate Cox proportional hazard regression model, an increase of 1 mL/kg PBW of first VT was associated with 26.1% increase in 30-day mortality (adjusted hazard ratio 1.261, 95% confidence interval [CI] 1.072-1.484, p < 0.01). CONCLUSION: First tidal volume, shortly after intubation, greater than 8 mL/kg PBW is an independent risk factor for mortality in complicated influenza infection with ARDS. Timely recognition of ARDS with strict adherence to protective ventilation strategy of lowering VT may be important in reducing mortality.

Predictors of survival in patients with influenza pneumonia-related severe acute respiratory distress syndrome treated with prone positioning.

BACKGROUND: Patients with influenza complicated with pneumonia are at high risk of rapid progression to acute respiratory distress syndrome (ARDS). Prone positioning with longer duration and lung-protective strategies might reduce the mortality level in ARDS. The aim of this study is to investigate the survival predictors of prone positioning in patients with ARDS caused by influenza pneumonia. METHODS: This retrospective study was conducted by eight tertiary referral centers in Taiwan. From January 1 to March 31 in 2016, all of the patients in intensive care units with virology-proven influenza pneumonia were collected, while all of those patients with ARDS and receiving prone positioning were enrolled. Demographic data, laboratory examinations, management records, ventilator settings and clinical outcomes were collected for analysis. RESULTS: During the study period, 336 patients with severe influenza pneumonia were screened and 263 patients met the diagnosis of ARDS. Totally, 65 patients receiving prone positioning were included for analysis. The 60-day survivors had lower Acute Physiology and Chronic Health Evaluation (APACHE) II score, pneumonia severity index (PSI), creatinine level and lower rate of receiving renal replacement therapy than non-survivors (22.4 ± 8.5 vs. 29.2 ± 7.4, p = 0.003; 106.6 ± 40.9 vs. 135.3 ± 48.6, p = 0.019; 1.2 ± 0.9 mg/dL vs. 3.1 ± 3.6 mg/dL, p = 0.040; and 4% vs. 42%, p < 0.005). Multivariate Cox regression analysis identified PSI (hazard ratio 1.020, 95% confidence interval 1.009-1.032; p < 0.001), renal replacement therapy (hazard ratio 6.248, 95% confidence interval 2.245-17.389; p < 0.001), and increase in dynamic driving pressure (hazard ratio 1.372, 95% confidence interval 1.095-1.718; p = 0.006) which were independent predictors associated with 60-day mortality. CONCLUSIONS: In the present study, in evaluating the effect of prone positioning in patients with influenza pneumonia-related ARDS, pneumonia severity index, renal replacement therapy and increase in dynamic driving pressure were associated with 60-day mortality in patients with influenza pneumonia-related ARDS receiving prone positioning.