Nationwide cohort study of independent risk factors for acute respiratory distress syndrome after trauma

Comorbid burden at ICU admission in COVID-19 compared to sepsis and acute respiratory distress syndrome

BACKGROUND

Comorbidities are similarly associated with short-term mortality for COVID-19, acute respiratory distress syndrome (ARDS) and sepsis in intensive care unit (ICU) patients, but their adjusted frequencies at admission are unknown. Thus, we aimed to evaluate the adjusted distribution, reported as odds ratios, of known risk factors (i.e., age, sex and comorbidities) for ICU admission between COVID-19, sepsis and ARDS patients in this nationwide registry-based study.

METHODS

In this cohort study, we included adult patients admitted to Swedish ICUs with COVID-19 (n = 7382) during the pandemic and compared them to patients admitted to ICU with sepsis (n = 22,354) or ARDS (n = 2776) during a pre-COVID-19 period. The main outcomes were the adjusted odds for comorbidities, sex, and age in multivariable logistic regression on diagnostic categories in patients admitted to ICU, COVID-19 or sepsis and COVID-19 or ARDS.

RESULTS

We found that most comorbidities, as well as age, had a stronger association with sepsis admission than COVID-19 admission with the exception of male sex, type 2 diabetes mellitus, and asthma that were more strongly associated with COVID-19 admission, while no difference was seen for chronic renal failure and obesity. For COVID-19 and ARDS admission most risk factors were more strongly associated with ARDS admission except for male sex, type 2 diabetes mellitus, chronic renal failure, and obesity which were more strongly associated with COVID-19 admission, whereas hypertension, chronic obstructive pulmonary disease and asthma were not different.

CONCLUSIONS

Patients admitted to ICU with sepsis or ARDS carry a heavier burden of comorbidity and high age than patients admitted with COVID-19. This is likely caused by a combination of: (1) respiratory failure in COVID-19 being less dependent on comorbidities than in other forms of ARDS, and the cause of critical illness in other infections causing sepsis and (2) COVID-19 patients being deferred admission in situations where patients with the other syndromes were admitted.

Steroids in acute respiratory distress syndrome: A panacea or still a puzzle?

Acute respiratory distress syndrome (ARDS) is a unique entity marked by various etiologies and heterogenous pathophysiologies. There remain concerns regarding the efficacy of particular medications for each severity level apart from respiratory support. Among several pharmacotherapies which have been examined in the treatment of ARDS, corticosteroids, in particular, have demonstrated potential for improving the resolution of ARDS. Nevertheless, it is imperative to consider the potential adverse effects of hyperglycemia, susceptibility to hospital-acquired infections, and the development of intensive care unit acquired weakness when administering corticosteroids. Thus far, a multitude of trials spanning several decades have investigated the role of corticosteroids in ARDS. Further stringent trials are necessary to identify particular subgroups before implementing corticosteroids more widely in the treatment of ARDS. This review article provides a concise overview of the most recent evidence regarding the role and impact of corticosteroids in the management of ARDS.

[Risk factors for acute respiratory distress syndrome in patients with traumatic hemorrhagic shock]

OBJECTIVE

To investigate the risk factors of acute respiratory distress syndrome (ARDS) after traumatic hemorrhagic shock.

METHODS

This was a retrospective cohort study of 314 patients with traumatic hemorrhagic shock at Trauma Medicine Center, Peking University People's Hospital from December 2012 to August 2021, including 152 male patients and 162 female patients, with a median age of 63.00 (49.75-82.00) years. The demographic data, past medical history, injury assessment, vital signs, laboratory examination and other indicators of these patients during hospitalization were recorded. These patients were divided into two groups, ARDS group (n=89) and non-ARDS group (n=225) according to whether there was ARDS within 7 d of admission. Risk factors for ARDS were identified using Logistic regression. The C-statistic expressed as a percentage [area under curve (AUC) of the receiver operating characteristic (ROC) curve] was used to assess the discrimination of the model.

RESULTS

The incidence of ARDS after traumatic hemorrhagic shock was 28.34%. Finally, Logistic regression model showed that the independent risk factors of ARDS after traumatic hemorrhagic shock included male, history of coronary heart disease, high acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, road traffic accident and elevated troponin Ⅰ. The OR and 95% confidence intervals (CI) were 4.01 (95%CI: 1.75-9.20), 5.22 (95%CI: 1.29-21.08), 1.07 (95%CI: 1.02-1.57), 2.53 (95%CI: 1.21-5.28), and 1.26 (95%CI: 1.02-1.57), respectively; the P values were 0.001, 0.020, 0.009, 0.014, and 0.034, respectively. The ROC curve was used to analyze the value of each risk factor in predicting ARDS. It was found that the AUC for predicting ARDS after traumatic hemorrhagic shock was 0.59 (95%CI: 0.51-0.68) for male, 0.55 (95%CI: 0.46-0.64) for history of coronary heart disease, 0.65 (95%CI: 0.57-0.73) for APACHE Ⅱ score, 0.58 (95%CI: 0.50-0.67) for road traffic accident, and 0.73 (95%CI: 0.66-0.80) for elevated troponin Ⅰ, with an overall predictive value of 0.81 (95%CI: 0.74-0.88).

CONCLUSION

The incidence of ARDS in patients with traumatic hemorrhagic shock is high, and male, history of coronary heart disease, high APACHE Ⅱ score, road traffic accident and elevated troponin Ⅰ are independent risk factors for ARDS after traumatic hemorrhagic shock. Timely monitoring these indicators is conducive to early detection and treatment of ARDS after traumatic hemorrhagic shock.

American Association for the Surgery of Trauma/American College of Surgeons Committee on Trauma clinical protocol for management of acute respiratory distress syndrome and severe hypoxemia

LEVEL OF EVIDENCE

Therapeutic/Care Management: Level V.

Alcohol Dependence and Rib Fracture Outcomes: A Systematic Review and Meta-Analysis

Chronic alcohol use has been associated with impaired pulmonary function, increased risk of pneumonia and poor outcomes after trauma. With a high incidence of rib fractures in this population, the clinical and physiological factors associated with alcohol dependence may influence how these patients recover from thoracic injuries. Therefore, the aim of the systematic review was to examine the effect of alcohol dependence on rib fracture outcomes. The Embase, PubMed and Web of Science databases were searched for studies examining adult patients with rib fractures, with and without a history of alcohol dependency. The outcomes of interest were mortality, pulmonary complications, intensive care length of stay, ventilator days and hospital length of stay. A meta-analysis was performed to combine the data and compare results. Three studies met the criteria for inclusion in the review and all studies were observational in design. Alcohol dependency was associated with increased mortality (OR 1.44 (95% CI: 1.33-1.56)), pneumonia (OR 2.14 (2.02-2.27)) and ARDS (OR 1.71(1.48-1.98)) as well as longer stays in hospital and intensive care (p<0.05). No difference was found in ventilator days between the two groups. Early intensive care review should be considered to reduce complications in this population alongside prompt management of withdrawal symptoms. However, limited primary research exists on this topic and the quality of current evidence is low. Additional primary research is needed to further understand this correlation and draw meaningful conclusions.

Factors associated with acute respiratory distress syndrome in brain-injured patients: A systematic review and meta-analysis

PURPOSE

Acute respiratory distress syndrome (ARDS) is common in patients with acute brain injury admitted to the ICU. We aimed to identify factors associated with ARDS in this population.

METHODS

We searched MEDLINE, Embase, Cochrane Central, Scopus, and Web of Science from inception to January 14, 2022. Three reviewers independently screened articles and selected English-language studies reporting risk factors for ARDS in brain-injured adult patients. Data were extracted on ARDS incidence, adjusted and unadjusted risk factors, and clinical outcomes. Risk of bias was reported using the Quality in Prognostic Studies tool. Certainty of evidence was assessed using GRADE.

RESULTS

We selected 23 studies involving 6,961,284 patients with acute brain injury. The pooled cumulative incidence of ARDS after brain injury was 17.0% (95%CI 10.7-25.8). In adjusted analysis, factors associated with ARDS included sepsis (odds ratio (OR) 4.38, 95%CI 2.37-8.10; high certainty), history of hypertension (OR 3.11, 95%CI 2.31-4.19; high certainty), pneumonia (OR 2.69, 95%CI 2.35-3.10; high certainty), acute kidney injury (OR 1.44, 95%CI 1.30-1.59; moderate certainty), admission hypoxemia (OR 1.67, 95%CI 1.29-2.17; moderate certainty), male sex (OR 1.30, 95%CI 1.06-1.58; moderate certainty), and chronic obstructive pulmonary disease (OR 1.27, 95%CI 1.13-1.44; moderate certainty). Development of ARDS was independently associated with increased odds of in-hospital mortality (OR 3.12, 95% CI 1.39-7.00).

CONCLUSIONS

Multiple risk factors are associated with ARDS in brain-injured patients. These findings could be used to develop prognostic models for ARDS or as prognostic enrichment strategies for patient enrolment in future clinical trials.

Changes in lung sialidases in male and female mice after bleomycin aspiration

Aim of the study: Sialidases, also called neuraminidases, are enzymes that cleave terminal sialic acids from glycoconjugates. In humans and mice, lung fibrosis is associated with desialylation of glycoconjugates and upregulation of sialidases. There are four mammalian sialidases, and it is unclear when the four mammalian sialidases are elevated over the course of inflammatory and fibrotic responses, whether tissue resident and inflammatory cells express different sialidases, and if sialidases are differentially expressed in male and females. Materials and Methods: To determine the time course of sialidase expression and the identity of sialidase expressing cells, we used the bleomycin model of pulmonary fibrosis in mice to examine levels of sialidases during inflammation (days 3 - 10) and fibrosis (days 10 - 21). Results: Bleomycin aspiration increased sialidase NEU1 at days 14 and 21 in male mice and day 10 in female mice. NEU2 levels increased at day 7 in male and day 10 in female mice. NEU3 appears to have a biphasic response in male mice with increased levels at day 7 and then at days 14 and 21, whereas in female mice NEU3 levels increased over 21 days. In control mice, the sialidases were mainly expressed by EpCAM positive epithelial cells, but after bleomycin, epithelial cells, CD45 positive immune cells, and alveolar cells expressed NEU1, NEU2, and NEU3. Sialidase expression was higher in male compared to female mice. There was little expression of NEU4 in murine lung tissue. Conclusions: These results suggest that sialidases are dynamically expressed following bleomycin, that sialidases are differentially expressed in male and females, and that of the four sialidases only NEU3 upregulation is associated with fibrosis in both male and female mice.

Oxygenation and Respiratory System Compliance Associated With Pulmonary Contusion

BACKGROUND

Blunt pulmonary contusions are associated with severe chest injuries and are independently associated with worse outcomes. Previous preclinical studies suggest that contusion progression precipitates poor pulmonary function; however, there are few current clinical data to corroborate this hypothesis. We examined pulmonary dynamics and oxygenation in subjects with pulmonary contusions to evaluate for impaired respiratory function.

METHODS

A chest injury database was reviewed for pulmonary contusions over 5 years at an urban trauma center. This database was expanded to capture mechanical ventilation parameters for the first 7 days on all patients with pulmonary contusion and who were intubated. Daily [Formula: see text]:[Formula: see text], oxygenation indexes (OI), and dynamic compliances were calculated. Pulmonary contusions were stratified by severity. The Fisher exact and chi square tests were performed on categorical variables, and Mann-Whitney U-tests were performed on continuous variables. Significance was assessed at a level of 0.05.

RESULTS A TOTAL OF

1,176 patients presented with pulmonary contusions, of whom, 301 subjects (25.6%) required intubation and had available invasive mechanical ventilation data. Of these, 144 (47.8%) had mild-moderate pulmonary contusion and 157 (52.2%) had severe pulmonary contusion. Overall injury severity score was high, with a median injury severity score of 29 (interquartile range, 22-38). The median duration of mechanical ventilation for mild-moderate pulmonary contusion was 7 d versus 10 d for severe pulmonary contusion (P = .048). All the subjects displayed moderate hypoxemia, which worsened until day 4-5 after intubation. Severe pulmonary contusion was associated with significantly worse early hypoxia on day 1 and day 2 versus mild-moderate pulmonary contusion. Severe pulmonary contusion also had a higher oxygenation index than mild-moderate pulmonary contusion. This trend persisted after adjustment for other factors, including transfusion and fluid administration.

CONCLUSIONS

Pulmonary contusions played an important role in the course of subjects who were acutely injured and required mechanical ventilation. Contusions were associated with hypoxemia not fully characterized by [Formula: see text]: [Formula: see text], and severe contusions had durable elevations in the oxygenation index despite confounders.

Sex-Based Differences in Human Neutrophil Chemorepulsion

A considerable amount is known about how eukaryotic cells move toward an attractant, and the mechanisms are conserved from Dictyostelium discoideum to human neutrophils. Relatively little is known about chemorepulsion, where cells move away from a repellent signal. We previously identified pathways mediating chemorepulsion in Dictyostelium, and here we show that these pathways, including Ras, Rac, protein kinase C, PTEN, and ERK1 and 2, are required for human neutrophil chemorepulsion, and, as with Dictyostelium chemorepulsion, PI3K and phospholipase C are not necessary, suggesting that eukaryotic chemorepulsion mechanisms are conserved. Surprisingly, there were differences between male and female neutrophils. Inhibition of Rho-associated kinases or Cdc42 caused male neutrophils to be more repelled by a chemorepellent and female neutrophils to be attracted to the chemorepellent. In the presence of a chemorepellent, compared with male neutrophils, female neutrophils showed a reduced percentage of repelled neutrophils, greater persistence of movement, more adhesion, less accumulation of PI(3,4,5)P₃, and less polymerization of actin. Five proteins associated with chemorepulsion pathways are differentially abundant, with three of the five showing sex dimorphism in protein localization in unstimulated male and female neutrophils. Together, this indicates a fundamental difference in a motility mechanism in the innate immune system in men and women.

Department of Defense Trauma Registry Infectious Disease Module Impact on Clinical Practice

BACKGROUND

The Joint Trauma System (JTS) is a DoD Center of Excellence for Military Health System trauma care delivery and the DoD's reference body for trauma care in accordance with National Defense Authorization Act for Fiscal Year 2017. Through the JTS, evidence-based clinical practice guidelines (CPGs) have been developed and subsequently refined to standardize and improve combat casualty care. Data are amassed through a single, centralized DoD Trauma Registry to support process improvement measures with specialty modules established as the registry evolved. Herein, we review the implementation of the JTS DoD Trauma Registry specialty Infectious Disease Module and the development of infection-related CPGs and summarize published findings on the subsequent impact of the Infectious Disease Module on combat casualty care clinical practice and guidelines.

METHODS

The DoD Trauma Registry Infectious Disease Module was developed in collaboration with the Infectious Disease Clinical Research Program (IDCRP) Trauma Infectious Disease Outcomes Study (TIDOS). Infection-related information (e.g., syndromes, antibiotic management, and microbiology) were collected from military personnel wounded during deployment June 1, 2009 through December 31, 2014 and medevac'd to Landstuhl Regional Medical Center in Germany before transitioning to participating military hospitals in the USA.

RESULTS

To support process improvements and reduce variation in practice patterns, data collected through the Infectious Disease Module have been utilized in TIDOS analyses focused on assessing compliance with post-trauma antibiotic prophylaxis recommendations detailed in JTS CPGs. Analyses examined compliance over three time periods: 6 months, one-year, and 5 years. The five-year analysis demonstrated significantly improved adherence to recommendations following the dissemination of the 2011 JTS CPG, particularly with open fractures (34% compliance compared to 73% in 2013-2014). Due to conflicting recommendations regarding use of expanded Gram-negative coverage with open fractures, infectious outcomes among patients with open fractures who received cefazolin or expanded Gram-negative coverage (cefazolin plus fluoroquinolones and/or aminoglycosides) were also examined in a TIDOS analysis. The lack of a difference in the proportion of osteomyelitis (8% in both groups) and the significantly greater recovery of Gram-negative organisms resistant to aminoglycosides or fluoroquinolones among patients who received expanded Gram-negative coverage supported JTS recommendations regarding the use of cefazolin with open fractures. Following recognition of the outbreak of invasive fungal wound infections (IFIs) among blast casualties injured in Afghanistan, the ID Module was refined to capture data (e.g., fungal culture and histopathology findings, wound necrosis, and antifungal management) needed for the TIDOS team to lead the DoD outbreak investigation. These data captured through the Infectious Disease Module provided support for the development of a JTS CPG for the prevention and management of IFIs, which was later refined based on subsequent TIDOS IFI analyses.

CONCLUSIONS

To improve combat casualty care outcomes and mitigate high-consequence infections in future conflicts, particularly in the event of prolonged field care, expansion, refinement, and a mechanism for sustainability of the DoD Trauma Registry Infectious Disease Module is needed to include real-time surveillance of infectious disease trends and outcomes.

The Michigan Radiation Oncology Quality Consortium: A Novel Initiative to Improve the Quality of Radiation Oncology Care

PURPOSE

Numerous quality measures have been proposed in radiation oncology, and initiatives to improve access to high-complexity care, quality, and equity are needed. We describe the design and evaluate impact of a voluntary statewide collaboration for quality improvement in radiation oncology initiated a decade ago.

METHODS AND MATERIALS

We evaluate compliance before and since implementation of annual metrics for quality improvement, using an observational dataset with information from over 20,000 patients treated in the 28 participating radiation oncology practices. At thrice-yearly meetings, experts have spoken regarding trends within the field and inspired discussions regarding potential targets for quality improvement. Blinded data on practices at various sites have been provided. Following Standards for Quality Improvement Reporting Excellence (SQUIRE) guidelines, we describe the approach and measures the program has implemented. To evaluate impact, we compare compliance at baseline and now with active measures using mixed effects regression models with site-level random effects.

RESULTS

Compliance has increased, including use of guideline-concordant hypofractionated radiotherapy, doses to targets/normal tissues, motion management, and consistency in delineating and naming contoured structures (a precondition for quality evaluation). For example, use of guideline-concordant hypofractionation for breast cancer increased from 47% to 97%, adherence to target coverage goals and heart dose limits for dose increased from 46% to 86%, motion assessment in patients with lung cancer increased from 52% to 94%, and use of standard nomenclature increased from 53% to 82% for lung patients and from 80% to 94% for breast patients (all p<0.001).

CONCLUSIONS

Although observational analysis cannot fully exclude secular trends, contextual data revealing slow uptake of best practices elsewhere in the US and qualitative feedback from participants suggests that this initiative has improved the consistency, efficiency, and quality of radiation oncology care in its member practices and may be a model for oncology quality improvement more generally.

Association between trauma exposure and respiratory disease-A Mendelian randomization study

BACKGROUND

Trauma is a well-known risk factor for many disease, but the effect of trauma on respiratory disease is unclarified. In the present study, we aimed to evaluate the association between trauma and respiratory disease.

METHOD

Using both United Kingdom biobank and Finnish biobank genome-wide association study data (GWAS), we performed a two-sample Mendelian randomization (MR) analysis to evaluate the relationship between trauma and respiratory disease. We used four methods including inverse-variance weighted (IVW), weighted median, Maximum likelihood, and MR-Egger in this MR analysis. The IVW MR was selected as the main method. We also performed multivariable Mendelian randomization (MVMR) to simultaneously assess the independent impact of trauma exposure on respiratory disease.

RESULTS

In the main two-sample MR analysis, trauma exposure was significantly associated with increased risk of respiratory disease (OR 1.15, 95%CI: 1.05-1.25). Besides, there was no heterogeneity and horizontal pleiotropy observed in the sensitivity analysis. After adjusting for pack years of smoking and body mass index (BMI), trauma exposure retained its association with respiratory disease (OR, 1.13, 95%CI, 1.04-1.23 adjusted by pack years of smoking; and OR, 1.11, 95%CI, 1.04-1.18 adjusted by BMI).

CONCLUSION

Our study discovered the association between trauma exposure and the increased risk of respiratory disease, suggesting the prevention and treatment with trauma to reduce the risk of respiratory disease.

Chest wall injuries due to cardiopulmonary resuscitation and the effect on in-hospital outcomes in survivors of out-of-hospital cardiac arrest

BACKGROUND

This study aimed to assess the prevalence of chest wall injuries due to cardiopulmonary resuscitation for out-of-hospital cardiac arrest (OHCA) and to compare in-hospital outcomes in patients with versus without chest wall injuries.

METHODS

A retrospective cohort study of all intensive care unit (ICU)-admitted patients who underwent cardiopulmonary resuscitation for OHCA between January 1, 2007, and December 2019 was performed. The primary outcome was the occurrence of chest wall injuries, as diagnosed on chest computed tomography. Chest wall injury characteristics such as rib fracture location, type, and dislocation were collected. Secondary outcomes were in-hospital outcomes and subgroup analysis of patients with good neurological recovery to identify those who could possibly benefit from the surgical stabilization of rib fractures.

RESULTS

Three hundred forty-four patients were included, of which 291 (85%) sustained chest wall injury. Patients with chest wall injury had a median of 8 fractured ribs (P25-P75, 4-10 ribs), which were most often undisplaced (on chest computed tomography) (n = 1,574 [72.1%]), simple (n = 1,948 [89.2%]), and anterior (n = 1,785 [77.6%]) rib fractures of ribs 2 to 7. Eight patients (2.3%) had a flail segment, and 136 patients (39.5%) had an anterior flail segment. Patients with chest wall injury had fewer ventilator-free days (0 days [P25-P75, 0-16 days] vs. 13 days [P25-P75, 2-22 days]; p = 0.006) and a higher mortality rate (n = 102 [54.0%] vs. n = 8 [22.2%]; p < 0.001) than those without chest wall injury. For the subgroup of patients with good neurological recovery, the presence of six or more rib fractures or a single displaced rib fracture was associated with longer hospital and ICU length of stay, respectively.

CONCLUSION

Cardiopulmonary resuscitation-related chest wall injuries in survivors of OHCA and especially rib fractures are common. Patients with chest wall injury had fewer ventilator-free days and a higher mortality rate. Patients with good neurological recovery might represent a subgroup of patients who could benefit from surgical stabilization of rib fractures.

LEVEL OF EVIDENCE

Therapeutic, level IV; Epidemiological, Level IV.

The Association Between Pulmonary Contusion Severity and Respiratory Failure

BACKGROUND

Pulmonary contusions (PCs) have historically been viewed as a serious complicating factor in thoracic injury. Recently, there has been conflicting evidence regarding the influence of PCs on outcomes; however, many studies do not stratify contusions by severity and may miss clinical associations. We sought to identify if contusion severity is associated with worse outcomes.

METHODS

A previously published chest wall injury database at an urban Level I trauma center was retrospectively reviewed. All severely injured subjects (defined as Injury Severity Score [ISS] ≥ 15) with moderate to severe thoracic injury (defined as a chest wall Abbreviated Injury Scale [AIS] ≥ 3) who required mechanical ventilation for > 24 h were stratified by contusion severity. Moderate to severe contusions were defined as AIS contusion ≥ 3 and Blunt Pulmonary Contusion 18 (BPC18) score ≥ 3.

RESULTS

Over 5 y, 3,836 patients presented with chest wall injuries, of which 1,176 (30.6%) had concomitant contusions. When screened for inclusion criteria, 339 subjects with contusions and 211 subjects without contusions (no-PC) were identified. Of these, 234 had moderate to severe contusions defined by AIS contusion ≥ 3 (PC-A) and 230 had moderate to severe contusions by BPC18 ≥ 3 (PC-B). Compared to no-PC, both PC-A and PC-B groups had significantly lower mortality (17.9% and 17.4%, respectively, vs 28.9%); however, PC-A and PC-B groups had longer durations of mechanical ventilation (6 and 7 d, respectively, vs 5 d), longer ICU length of stay (10 and 10 vs 8 d), and longer overall hospital length of stay (15 and 15 vs 13 d).

CONCLUSIONS

In severely injured polytrauma patients, PCs are seen with more severe chest injuries. Furthermore, moderate to severe contusions are associated with longer durations of mechanical ventilation, ICU length of stay, and hospital length of stay. Despite practice pattern changes, contusions appear to contribute significantly to the clinical course of the blunt chest wall injured patients.

Prognostic factors for development of acute respiratory distress syndrome following traumatic injury - a systematic review and meta-analysis

PURPOSE

To summarise the prognostic associations between various clinical risk factors and the development of the acute respiratory distress syndrome (ARDS) following traumatic injury.

METHODS

We conducted this review in accordance with the PRISMA and CHARMS guidelines. We searched six databases from inception through December 2020. We included English language studies describing the clinical risk factors associated with the development of post-traumatic ARDS, as defined by either the American-European Consensus Conference or the Berlin definition. We pooled adjusted odds ratios for prognostic factors using the random effects method. We assessed risk of bias using the QUIPS tool and certainty of findings using GRADE methodology.

RESULTS

We included 39 studies involving 5 350 927 patients. We identified the amount of crystalloid resuscitation as a potentially modifiable prognostic factor associated with the development of post-traumatic ARDS (adjusted odds ratio [aOR] 1.19 for each additional liter of crystalloid administered within first 6 h after injury, 95% CI 1.15 to 1.24, high certainty). Non-modifiable prognostic factors with a moderate or high certainty of association with post-traumatic ARDS included increasing age, non-Hispanic white race, blunt mechanism of injury, presence of head injury, pulmonary contusion, or rib fracture; and increasing chest injury severity.

CONCLUSION

We identified one important modifiable factor, the amount of crystalloid resuscitation within the first 24 h of injury, and several non-modifiable factors associated with development of post-traumatic ARDS. This information should support the judicious use of crystalloid resuscitation in trauma patients and may inform the development of a risk-stratification tools.

Possible Predictive Factor of Acute Respiratory Distress Syndrome Development After Mild Traumatic Brain Injury: A Single Rural Trauma Center Preliminary Study

Introduction Acute respiratory distress syndrome (ARDS) after mild traumatic brain injury (TBI) can be associated with significant morbidity and mortality. This study aimed to evaluate the potential predictive factors of ARDS development following mild TBI in trauma patients. Methods A retrospective chart review was done for adult trauma patients with mild TBI (GCS 13-15) requiring admission at our center from 2012 to 2020. Linear regression analysis and chi-square test were utilized to identify independent predictors of the association with ARDS in adults with mild TBI.  Results A total of 784 mild TBI patients were admitted during the time of interest; 34 patients developed ARDS during their index hospitalization. Patients who had ARDS were more likely to have acute kidney injury (AKI; p < 0.0001), sepsis (p < 0.01), rib fractures (p < 0.05), use of anticoagulants (p < 0.001), deep vein thrombosis (p < 0.001), transfusion during the first 4four hours upon admission (p = 0.01), intravenous fluid (IVF) resuscitation during the first four hours (p <0.05), the first eight hours (p = 0.01), the first 12 hours (p = 0.03), and intubation upon the admission (p < 0.0001). ARDS associated with mild TBI demonstrated a statistically significant increase in mortality during the index hospitalization (p < 0.0001). Conclusion ARDS after mild TBI can be associated with significant morbidity and mortality. Key risk factors identified include AKI, sepsis, anticoagulant use, deep vein thrombosis (DVT), transfusion in the first four hours, IVF resuscitation in the first four, eight, and 12 hours, and intubation upon admission.

Quantitative Evaluation of Embolic Load in Femoral and Tibial Shaft Fractures Treated With Reamed Intramedullary Fixation

OBJECTIVES

To compare the volume of embolic load during intramedullary fixation of femoral and tibial shaft fractures. Our hypothesis was that tibial intramedullary nails (IMNs) would be associated with less volume of intravasation of marrow than IM nailing of femur fractures.

DESIGN

Prospective observational study.

SETTING

Urban Level I trauma center.

PATIENTS/PARTICIPANTS

Twenty-three patients consented for the study: 14 with femoral shaft fractures and 9 with tibial shaft fractures.

INTERVENTION

All patients underwent continuous transesophageal echocardiography, and volume of embolic load was evaluated during 5 distinct stages: postinduction, initial guide wire, reaming (REAM), nail insertion, and postoperative.

MAIN OUTCOME MEASUREMENTS

Volume of embolic load was measured based on previously described luminosity scores. The embolic load based on fracture location and procedure stage was evaluated using a mixed effects model.

RESULTS

The IMN procedure increased the embolic load by 215% (-12% to 442%, P = 0.07) in femur patients relative to tibia patients after adjusting for baseline levels. Of the 5 steps measured, REAM was associated with the greatest increase in embolic load relative to the guide wire placement and controlling for fracture location (421%, 95% confidence interval: 169%-673%, P < 0.01).

CONCLUSIONS

Femoral shaft IMN fixation was associated with a 215% increase in embolic load in comparison with tibial shaft IMN fixation, with the greatest quantitative load during the REAM stage; however, both procedures produce embolic load.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Metabolic surgery may protect against admission for COVID-19 in persons with nonalcoholic fatty liver disease

Background

SARS-CoV-2 (COVID-19) disease causes significant morbidity and mortality through increased inflammation and thrombosis. Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are states of chronic inflammation and indicate advanced metabolic disease.

Objective

The purpose of this observational study was to characterize the risk of hospitalization for COVID-19 in patients with NAFLD/NASH and evaluate the mitigating effect of various metabolic treatments.

Setting

Retrospective analysis of electronic medical record data of 26,896 adults from a 12-hospital Midwest healthcare system with a positive COVID-19 polymerase chain reaction (PCR) test from March 1, 2020, to January 26, 2021.

Methods

Variable selection was guided by the least absolute shrinkage and selection operator (LASSO) method, and multiple imputation was used to account for missing data. Multivariable logistic regression and competing risk models were used to assess the odds of being hospitalized within 45 days of a COVID-19 diagnosis. Analysis assessed the risk of hospitalization among patients with a prescription for metformin and statin use within the 3 months prior to the COVID-19 PCR result, history of home glucagon-like peptide 1 receptor agonist (GLP-1 RA) use, and history of metabolic and bariatric surgery (MBS). Interactions were assessed by sex and race.

Results

A history of NAFLD/NASH was associated with increased odds of admission for COVID-19 (odds ratio [OR], 1.88; 95% confidence interval [CI], 1.57–2.26; P < .001) and mortality (OR, 1.96; 95% CI, 1.45–2.67; P < .001). Each additional year of having NAFLD/NASH was associated with a significant increased risk of being hospitalized for COVID-19 (OR, 1.24; 95% CI, 1.14–1.35; P < .001). NAFLD/NASH increased the risk of hospitalization in men, but not women, and increased the risk of hospitalization in all multiracial/multiethnic subgroups. Medication treatments for metabolic syndrome were associated with significantly reduced risk of admission (OR, .81; 95% CI, .67–.99; P < .001 for home metformin use; OR, .71; 95% CI, .65–.83; P < .001 for home statin use). MBS was associated with a significant decreased risk of admission (OR, .48; 95% CI, .33–.69; P < .001).

Conclusions

NAFLD/NASH is a significant risk factor for hospitalization for COVID-19 and appears to account for risk attributed to obesity. Other significant risks include factors associated with socioeconomic status and other co-morbidities, such as history of venous thromboembolism. Treatments for metabolic disease mitigated risks from NAFLD/NASH. More research is needed to confirm the risk associated with visceral adiposity, and patients should be screened for and informed of treatments for metabolic syndrome.

Retrospective study on rib fractures: smoking and alcohol matter for mortality and complications

Background

Rib fractures and substance use are both common in trauma patients, but there is little data on how smoking and alcohol use may be associated with outcomes in these patients. We assessed the association between smoking or alcohol use disorder (AUD) and outcomes in patients with rib fractures.

Methods

We used institutional databases to conduct a retrospective review of patients with rib fractures at the only American College of Surgeons-verified adult level 1 trauma center in a rural state between 2015 and 2019. The key exposure variables were smoking and AUD. The key outcome variables were mortality and pulmonary complications (pneumonia, adult respiratory distress syndrome, and pneumothorax). We used multivariable regression for analysis and directed acyclic graphs to identify variables for adjustment.

Results

We identified 1880 eligible patients with rib fractures, including 693 (37%) who were smokers and 204 (11%) who had AUD. Compared with non-smokers, smokers were younger, more often male, and had lower mortality rates. Regression showed that smokers had a lower likelihood of mortality (OR 0.48; 95% CI 0.27 to 0.87; p=014). Likelihood of pneumonia, ARDS, and pneumothorax was not different between smokers and non-smokers. Compared with patients without AUD, patients with AUD were older, more often male, and had higher likelihood of pneumonia and lower likelihood of pneumothorax. Regression showed that patients with AUD had higher likelihood of pneumonia (OR 1.82; 95% CI 1.24 to 2.68; p=0.002) and lower likelihood of pneumothorax (OR 0.51; 95% CI 0.33 to 0.75; p=0.002).

Discussion

In trauma patients with rib fractures treated at a level 1 trauma center over 5 years, smoking was associated with decreased risk of mortality. These findings have implications for risk stratification and clinical decision-making for patients with rib fractures.

Level of evidence

III

The Chest Wall Injury Society Recommendations for Reporting Studies of Surgical Stabilization of Rib Fractures

BACKGROUND

Publications investigating the efficacy of surgical stabilization of rib fractures (SSRF) have increased exponentially. However, there is currently no standardized reporting structure for these studies, rendering both comparisons and extrapolation problematic.

METHODS

A subject matter expert group was formed by the Chest Wall Injury Society. This group conducted a review of the SSRF investigational literature and identified variable reporting within several general categories of relevant parameters. A compliment of guidelines was then generated.

RESULTS

The reporting guidelines consist of 26 recommendations in the categories of: (1) study type, (2) patient and injury characteristics, (3) patient treatments, (4) outcomes, and (5) statistical considerations.

CONCLUSION

Our review identified inconsistencies in reporting within the investigational SSRF literature. In response to these inconsistencies, we propose a set of recommendations to standardize reporting of original investigations into the efficacy of SSRF.

Mortality prediction for patients with acute respiratory distress syndrome based on machine learning: a population-based study

Background

Traditional scoring systems for patients' outcome prediction in intensive care units such as Oxygenation Saturation Index (OSI) and Oxygenation Index (OI) may not reliably predict the clinical prognosis of patients with acute respiratory distress syndrome (ARDS). Thus, none of them have been widely accepted for mortality prediction in ARDS. This study aimed to develop and validate a mortality prediction method for patients with ARDS based on machine learning using the Medical Information Mart for Intensive Care (MIMIC-III) and Telehealth Intensive Care Unit (eICU) Collaborative Research Database (eICU-CRD) databases.

Methods

Patients with ARDS were selected based on the Berlin definition in MIMIC-III and eICU-CRD databases. The APPS score (using age, PaO₂/FiO₂, and plateau pressure), Simplified Acute Physiology Score II (SAPS-II), Sepsis-related Organ Failure Assessment (SOFA), OSI, and OI were calculated. With MIMIC-III data, a mortality prediction model was built based on the random forest (RF) algorithm, and the performance was compared to those of existing scoring systems based on logistic regression. The performance of the proposed RF method was also validated with the combined MIMIC-III and eICU-CRD data. The performance of mortality prediction was evaluated by using the area under the receiver operating characteristics curve (AUROC) and performing calibration using the Hosmer-Lemeshow test.

Results

With the MIMIC-III dataset (308 patients, for comparisons with the existing scoring systems), the RF model predicted the in-hospital mortality, 30-day mortality, and 1-year mortality with an AUROC of 0.891, 0.883, and 0.892, respectively, which were significantly higher than those of the SAPS-II, APPS, OSI, and OI (all P<0.001). In the multi-source validation (the combined dataset of 2,235 patients in MIMIC-III and 331 patients in eICU-CRD), the RF model achieved an AUROC of 0.905 and 0.736 for predicting in-hospital mortality for the MIMIC-III and eICU-CRD datasets, respectively. The calibration plots suggested good fits for our RF model and these scoring systems for predicting mortality. The platelet count and lactate level were the strongest predictive variables for predicting in-hospital mortality.

Conclusions

Compared to the existing scoring systems, machine learning significantly improved performance for predicting ARDS mortality. Validation with multi-source datasets showed a relatively robust generalisation ability of our prediction model.

Radiomics score predicts acute respiratory distress syndrome based on the initial CT scan after trauma

OBJECTIVES

Acute respiratory distress syndrome (ARDS) constitutes a major factor determining the clinical outcome in polytraumatized patients. Early prediction of ARDS is crucial for timely supportive therapy to reduce morbidity and mortality. The objective of this study was to develop and test a machine learning-based method for the early prediction of ARDS derived from the first computed tomography scan of polytraumatized patients after admission to the hospital.

MATERIALS AND METHODS

One hundred twenty-three patients (86 male and 37 female, age 41.2 ± 16.4) with an injury severity score (ISS) of 16 or higher (31.9 ± 10.9) were prospectively included and received a CT scan within 1 h after the accident. The lungs, including air pockets and pleural effusions, were automatically segmented using a deep learning-based algorithm. Subsequently, we extracted radiomics features from within the lung and trained an ensemble of gradient boosted trees (GBT) to predict future ARDS.

RESULTS

Cross-validated ARDS prediction resulted in an area under the curve (AUC) of 0.79 for the radiomics score compared to 0.66 for ISS, and 0.68 for the abbreviated injury score of the thorax (AIS-thorax). Prediction using the radiomics score yielded an f1-score of 0.70 compared to 0.53 for ISS and 0.57 for AIS-thorax. The radiomics score achieved a sensitivity and specificity of 0.80 and 0.76.

CONCLUSIONS

This study proposes a radiomics-based algorithm for the prediction of ARDS in polytraumatized patients at the time of admission to hospital with an accuracy that competes and surpasses conventional scores despite the heterogeneous, and therefore more realistic, scanning protocols.

KEY POINTS

• Early prediction of acute respiratory distress syndrome in polytraumatized patients is possible, even when using heterogenous data. • Radiomics-based prediction resulted in an area under the curve of 0.79 compared to 0.66 for the injury severity score, and 0.68 for the abbreviated injury score of the thorax. • Highlighting the most relevant lung regions for prediction facilitates the understanding of machine learning-based prediction.

Increasing BMI is associated with higher mortality, worsening outcomes and highly specific injury patterns following trauma: A multi-institutional analysis of 191,274 patients

BACKGROUND

As the prevalence of obesity has increased, trauma centers are faced with managing this expanding demographics' unique care requirements. Research on the effects of body mass index (BMI) in trauma patients remains conflicting. This study aims to evaluate the impact of BMI on patterns of injury and patient outcomes following trauma.

METHODS

Patients from 87 hospitals' trauma registries were selected. Those missing height, weight, disposition, or who died in the emergency department were excluded. The BMI categories were calculated from admission height and weight and verified against the electronic medical records. Patients were grouped by the National Institutes of Health-defined obesity class and compared by rate of mortality and in-hospital complications. Logistic regression was used to estimate associations, adjusting for age, gender, race, Injury Severity Score, and number of comorbidities.

RESULTS

There were 191,274 patients, 53% male; mean age was 60.4 years, mean Glasgow Coma Scale score 14.4, mean Injury Severity Score of 8.8, and 40.4% normal weight. Increased BMI was associated with an injury pattern of increased rates of extremity fractures (humerus, femur, tibia/fibula) and decreased rates of hip fractures and head injuries. Compared with the normal weight group, patients were more likely to die if they were Underweight (adjusted odds ratio [AOR], 1.18; 95% confidence interval [CI], 1.01-1.38), obese class II (AOR, 1.24; 95% CI, 1.07-1.45), or obese class III (AOR, 1.55; 95% CI, 1.29-1.87). Obese class III was associated with higher odds of a National Trauma Data Standard complication (AOR, 1.20; 95% CI, 1.11-1.30).

CONCLUSION

In this large multicenter study, increasing BMI and lower than normal BMI were strongly associated with higher mortality. Increasing BMI was also associated with longer length of stay, increased complications, and unique injury patterns. These untoward outcomes, coupled with a distinct injury pattern, warrant care guidelines specific to trauma patients with higher BMI, as well as those with BMI lower than normal.

LEVEL OF EVIDENCE

Epidemiological, Level III.

Club Cell Protein 16 Attenuates CD16brightCD62dim Immunosuppressive Neutrophils in Damaged Tissue upon Posttraumatic Sepsis-Induced Lung Injury

Background

Recently, identification of immunosuppressive polymorphonuclear leukocytes (PMNL) that were traditionally described as proinflammatory cells emerged in the field of posttraumatic immunity. To understand their local and remote distribution after trauma, PMNL-subsets and the impact of immunomodulatory Club Cell protein (CC)16 that correlates with pulmonary complications were assessed.

Methods

C57BL/6N mice were divided into three groups, receiving isolated blunt chest trauma (TxT), undergoing TxT followed by cecal ligation and puncture (CLP, TxT + CLP) after 24 h, or sham undergoing analgosedation (n = 18/group). Further, each group was subdivided into three groups receiving either no treatment (ctrl) or intratracheal neutralization of CC16 by application of anti-CC16-antibody or application of an unspecific IgG control antibody (n = 6/group). Treatment was set at the time point after TxT. Analyses followed 6 h post-CLP. PMNL were characterized via expression of CD11b, CD16, CD45, CD62L, and Ly6G by flow cytometry in bone marrow (BM), blood, spleen, lung, liver, and bronchoalveolar and peritoneal lavage fluid (BALF and PL). Apoptosis was assessed by activated (cleaved) caspase-3. Results from untreated ctrl and IgG-treated mice were statistically comparable between all corresponding sham, TxT, and TxT + CLP groups.

Results

Immature (CD16^dimCD62L^bright) PMNL increased significantly in BM, circulation, and spleen after TxT vs. sham and were significantly attenuated in the lungs, BALF, PL, and liver. Classical-shaped (CD16^brightCD62L^bright) PMNL increased after TxT vs. sham in peripheral tissue and were significantly attenuated in circulation, proposing a trauma-induced migration of mature or peripheral differentiation of circulating immature PMNL. Immunosuppressive (CD16^brightCD62L^dim) PMNL decreased significantly in the lungs and spleen, while they systemically increased after TxT vs. sham. CLP in the TxT + CLP group reduced immunosuppressive PMNL in PL and increased their circulatory rate vs. isolated TxT, showing local reduction in affected tissue and their increase in nonaffected tissue. CC16 neutralization enhanced the fraction of immunosuppressive PMNL following TxT vs. sham and decreased caspase-3 in the lungs post-CLP in the TxT + CLP group, while apoptotic cells in the liver diminished post-TxT. Posttraumatic CC16 neutralization promotes the subset of immunosuppressive PMNL and antagonizes their posttraumatic distribution.

Conclusion

Since CC16 affects both the distribution of PMNL subsets and apoptosis in tissues after trauma, it may constitute as a novel target to beneficially shape the posttraumatic tissue microenvironment and homeostasis to improving outcomes.

Incidence and related factors of hypoxia associated with elderly femoral neck fractures in the emergency department setting

Aim

Femoral neck fractures in elderly patients needing oxygen therapy are often encountered in the emergency department. This single‐center, retrospective, observational study aimed to examine the frequency, cause, and factors related to hypoxia in elderly patients with femoral neck fractures.

Methods

We analyzed data from 241 patients admitted to Okayama Saiseikai General Hospital (Okayama, Japan) from April 2016 to March 2019. Hypoxia was defined as PaO₂ / FiO₂ ratio under 300. The independent factors for hypoxia were determined by multiple logistic regression analysis.

Results

There were 194 patients who met the study inclusion criteria, 148 in the non‐hypoxia group and 46 in the hypoxia group. The hypoxia group included patients with pneumonia (n = 3), chronic obstructive pulmonary disease (n = 2), pulmonary edema (n = 1), and pulmonary embolization (n = 1). The cause of hypoxia was undetermined in 39 cases. However, occult fat embolism syndrome was suspected in 29 of these 39 cases based on Gurd and Wilson criteria after considering clinical examination results. Barthel indexes were significantly lower in the hypoxia group on discharge. Age (adjusted odds ratio [OR] 1.07; 95% confidence interval [CI], 1.00–1.14; P = 0.038), D‐dimer (adjusted OR 1.02; 95% CI, 1.00–1.03; P = 0.005), and transtricuspid pressure gradient (adjusted OR 1.03; 95% CI, 1.00–1.07; P = 0.015) were independently associated with the hypoxia.

Conclusion

We found that hypoxia, including undetermined hypoxia, was commonly encountered in the emergency department. Hypoxia in elderly patients with femoral neck fractures was associated with age, D‐dimer, and transtricuspid pressure gradient and needs further investigation.

Natural and engineered chemokine (C-X-C motif) receptor 4 agonists prevent acute respiratory distress syndrome after lung ischemia-reperfusion injury and hemorrhage

We compared therapeutic properties of natural and engineered chemokine (C-X-C motif) receptor 4 (CXCR4) agonists in a rat acute respiratory distress syndrome (ARDS) model utilizing the PaO₂/FiO₂-ratio as a clinically relevant primary outcome criterion. Ventilated rats underwent unilateral lung ischemia from t = 0–70 min plus hemorrhage to a mean arterial blood pressure (MAP) of 30 mmHg from t = 40–70 min, followed by reperfusion/fluid resuscitation until t = 300 min. Natural CXCR4 agonists (CXCL12, ubiquitin) and engineered CXCL12 variants (CXCL12₁, CXCL2₂, CXCL12K27A/R41A/R47A, CXCL12 (3–68)) were administered within 5 min of fluid resuscitation. Animals treated with vehicle or CXCL12 (3–68) reached criteria for mild and moderate ARDS between t = 90–120 min and t = 120–180 min, respectively, and remained in moderate ARDS until t = 300 min. Ubiquitin, CXCL12, CXCL12₁ and CXCL12₂ prevented ARDS development. Potencies of CXCL12/CXCL12₁/CXCL12₂ were higher than the potency of ubiquitin. CXCL12K27A/R41A/R47A was inefficacious. CXCL12₁ > CXCL12 stabilized MAP and reduced fluid requirements. CXCR4 agonists at doses that preserved lung function reduced histological injury of the post-ischemic lung and reduced mortality from 55 to 9%. Our findings suggest that CXCR4 protein agonists prevent development of ARDS and reduce mortality in a rat model, and that development of new engineered protein therapeutics with improved pharmacological properties for ARDS is possible.

Alcohol Use Disorder Is Bad for Broken Ribs: A Nationwide Analysis of 19,638 Patients With Rib Fractures

BACKGROUND

Alcohol use disorder (AUD) has deleterious effects on many organ systems. The aim of our study was to assess the impact of AUD on outcomes in patients with rib fractures. We hypothesized that AUD is associated with increased risk adverse outcomes.

METHODS

We performed a 2013-2014 retrospective analysis of all adult trauma patients diagnosed with rib fractures from the American College of Surgeons-Trauma Quality Improvement Program database. We excluded patients who were acutely intoxicated with alcohol. Patients were stratified into two groups: AUD + and AUD -. A 1:1 ratio propensity score matching for demographics, admission vitals, injury severity, smoking status, operative intervention, and number of rib fractures was performed. Outcome measures were in-hospital complications, mortality, hospital and intensive care unit length of stay, and ventilator days.

RESULTS

We matched 19,638 patients (AUD +:9,819, AUD -:9819). Mean age was 53 ± 22y, and median injury severity score was 15[10-20]. Matched groups were similar in age (P = 0.18), smoking status (P = 0.82), injury severity score (P = 0.28), chest Abbreviated Injury Scale (P = 0.24), and number of rib fractures (2[1-4] versus 2[1-4], P = 0.86). Alcoholic patients had higher rates of pneumonia (18.1% versus 9.2%, P < 0.01), unplanned intubation (18.5% versus 9.7, P < 0.001), sepsis (10.8% versus 6.3%, P < 0.001), acute respiratory distress syndrome (12.2% versus 7.4%, P < 0.001), and mortality (8.0 versus 5.7%, P < 0.001). Patients with AUD spent more days in the hospital and intensive care unit . There was no difference in ventilator days between the two groups.

CONCLUSIONS

Patients with AUD and rib fractures had higher rates of adverse events than patients without AUD. Early identification of patients with rib fractures with AUD may allow better resource allocation and help improve outcomes.

LEVEL OF EVIDENCE

Level III prognostic.

Shoulder injuries in polytraumatized patients: an analysis of the TraumaRegister DGU®

Background

The aim of the present study was to analyze the prevalence, epidemiology and relevance of shoulder injuries in polytraumatized patients in a large national trauma database.

We hypothesize a high prevalence of shoulder injuries in traffic accidents and a high prevalence of concomitant injuries of the thorax leading to an aggravated clinical course and higher Injury Severity Score (ISS). Furthermore, we hypothesize an increased rate of surgical treatment with the severity of the injury.

Materials and methods

The retrospective analysis is based on the database (2002–2013) of the TraumaRegister DGU® and includes statistical data from 608 hospitals. The severity of injuries and trauma were scaled using the Abbreviated Injury Scale (AIS), and the Injury Severity Score (ISS), respectively. Patients with an ISS ≥ 16 were included in the study, and injuries were subdivided according to their anatomical involvement and analyzed with respect to the trauma mechanism and the resulting injuries.

Results

In this study, 54,076 cases of patients with an ISS ≥ 16 were analyzed. Shoulder injuries occurred in 15,115 patients (27.9%). Of these, 68.5% were caused by traffic accidents, especially in motorbike, bicycle, and pedestrian accidents. We found more shoulder injuries in blunt trauma mechanisms. Moreover, patients with shoulder injuries spent on average 1.7 more days on the intensive care unit (ICU), or intermediate care unit (IMCU), according to the severity of the injury, and had longer overall hospital stays (26.2 vs. 24.1 days) than patients without shoulder injuries. The overall ISS was increased in patients with shoulder injuries, whereas an increase of mortality could not be identified. Concomitant thoracic injuries occurred significantly more often in patients with shoulder injuries (82.9% vs. 69.6%). Injuries of the abdomen, pelvis, and lower extremity showed no correlation with shoulder injuries, whereas head and spine injuries showed a significant correlation.

Conclusion

Shoulder injuries are very common in polytraumatized patients. Together with their distinctive concomitant injuries, they have an aggravating impact on the clinical progress. Our data confirm the correlation with thoracic injuries. Furthermore, we identified an increased risk of shoulder injuries in motorbike, bicycle, and pedestrian accidents. An increase in mortality could not be identified.

Does Intramedullary Nail Fixation of the Tibia Pose the Same Risk of Pulmonary Complications as Intramedullary Nail Fixation of the Femur? A Propensity Score-Matched Analysis

OBJECTIVES

To compare duration of mechanical ventilation and pulmonary outcomes in patients treated with intramedullary nail (IMN) fixation of the tibia versus the femur.

DESIGN

Retrospective cohort study.

SETTING

Level I trauma center.

PATIENTS

One thousand thirty patients were categorized based on treatment: those treated with IMN of the tibia (n = 515) and those treated with IMN of the femur (n = 515).

INTERVENTION

IMN fixation of tibial and femoral fractures.

OUTCOME MEASUREMENTS

The primary outcome was duration of mechanical ventilation. Secondary outcomes included length of intensive care unit (ICU) stay and risk of tracheostomy, pulmonary embolism (PE), acute respiratory distress syndrome (ARDS), and mortality.

RESULTS

In an unadjusted analysis, femoral fractures were associated with increase in ventilator days (mean difference, 1.4; P < 0.001), ICU days (mean difference, 1.8; P < 0.001), and odds of tracheostomy (odds ratio, 1.7; P < 0.01). No difference was shown in likelihood of PE, ARDS, or mortality (P > 0.2). Propensity score-matched estimates showed no differences in any measured outcomes (P > 0.40). In patients with Injury Severity Scores >17, we found no difference in length of ventilator or ICU days or likelihood of tracheostomy, PE, ARDS, or mortality in the unadjusted (P > 0.2) or propensity score-matched estimates (P > 0.3).

CONCLUSIONS

These findings suggest that IMN fixation of the tibia is associated with duration of mechanical ventilation and risk of poor pulmonary outcomes similar to those of femoral nailing, after adjustment for baseline characteristics.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Pediatric Acute Respiratory Distress Syndrome (PARDS) in Children With Pulmonary Contusion

OBJECTIVE

There is paucity of data about prevalence of pediatric acute respiratory distress syndrome (PARDS) in children with pulmonary contusion (PC). We intend to evaluate PC in children with chest trauma and the association between PC and PARDS.

DESIGN

Retrospective review of Institutional Trauma Registry for patients with trauma.

SETTING

Level 1 trauma center.

PATIENTS

Age 18 years and younger with a diagnosis of PC.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the 1916 children with trauma, 50 (2.6%) had PC. Patients with PC and PARDS had lower Glasgow Coma Scale (GCS) score (7 [3-15] vs 15 [15-15], P = .0003), higher Injury Severity Scale (ISS) score (29 [22-34] vs 19 [14-22], P = .004), lower oxygen saturations (96 [93-99] days vs 99 [98-100] days, P = .0009), higher FiO₂ (1 [1-1] vs 0.21 [0.21-0.40], P < .0001), lower oxygen saturation/FiO₂ (S/F) ratios (97 [90-99] vs 457 [280-471], P < .0001), need for invasive mechanical ventilation (IMV; 86% vs 23%, P < .0001), and mortality (28% vs 0%, P = .006) compared to those without PARDS. Forty-two percent (21/50) of patients needed IMV, of these 61% (13/21) had PARDS. Patients who needed IMV had significantly lower GCS score (8 [3-11] vs 15 [15-15], P < .0001), higher ISS score (27 [22-34] vs 18 [14-22], P = .002), longer length of stay (LOS; 7.5 [4-14] days vs 3.3 [2-5] days, P = .003), longer hospital LOS (18 [7.0-25] vs 5 [4-11], P = .008), higher PARDS rate (62% vs 7%, P < .0001), and lower S/F ratios (99 [94-190] vs 461 [353-471], P < .0001) compared to those who did not require IMV. Lower GCS score was independently associated with both PARDS and need for IMV.

CONCLUSIONS

Pediatric ARDS in children with PC is independently associated with lower GCS score, and its presence significantly increased morbidity and mortality. Further larger studies are needed to explore association of lower GCS and higher injury score in children with PARDS and PC.

Endogenous Uteroglobin as Intrinsic Anti-inflammatory Signal Modulates Monocyte and Macrophage Subsets Distribution Upon Sepsis Induced Lung Injury

Sepsis is a serious clinical condition which can cause life-threatening organ dysfunction, and has limited therapeutic options. The paradigm of limiting excessive inflammation and promoting anti-inflammatory responses is a simplified concept. Yet, the absence of intrinsic anti-inflammatory signaling at the early stage of an infection can lead to an exaggerated activation of immune cells, including monocytes and macrophages. There is emerging evidence that endogenous molecules control those mechanisms. Here we aimed to identify and describe the dynamic changes in monocyte and macrophage subsets and lung damage in CL57BL/6N mice undergoing blunt chest trauma with subsequent cecal ligation and puncture. We showed that early an increase in systemic and activated Ly6C⁺CD11b⁺CD45⁺Ly6G^- monocytes was paralleled by their increased emigration into lungs. The ratio of pro-inflammatory Ly6C^highCD11b⁺CD45⁺Ly6G^- to patrolling Ly6C^lowCD11b⁺CD45⁺Ly6G^- monocytes significantly increased in blood, lungs and bronchoalveolar lavage fluid (BALF) suggesting an early transition to inflammatory phenotypes during early sepsis development. Similar to monocytes, the level of pro-inflammatory Ly6C^highCD45⁺F4/80⁺ macrophages increased in lungs and BALF, while tissue repairing Ly6C^lowCD45⁺F4/80⁺ macrophages declined in BALF. Levels of inflammatory mediators TNF-α and MCP-1 in blood and RAGE in lungs and BALF were elevated, and besides their boosting of inflammation via the recruitment of cells, they may promote monocyte and macrophage polarization, respectively, toward the pro-inflammatory phenotype. Neutralization of uteroglobin increased pro-inflammatory cytokine levels, activation of inflammatory phenotypes and their recruitment to lungs; concurrent with increased pulmonary damage in septic mice. In in vitro experiments, the influence of uteroglobin on monocyte functions including migratory behavior, TGF-β1 expression, cytotoxicity and viability were proven. These results highlight an important role of endogenous uteroglobin as intrinsic anti-inflammatory signal upon sepsis-induced early lung injury, which modules the early monocyte/macrophages driven inflammation.

Short Summary

Blunt chest injury is the third largest cause of death following major trauma, and ongoing excessive pro-inflammatory immune response entails high risk for the development of secondary complications, such as sepsis, with limited therapeutic options. In murine double hit trauma consisting of thoracic trauma and subsequent cecal ligation and puncture, we investigated the cytokine profile, pulmonary epithelial integrity and phenotypic shift of patrolling Ly6C^lowCD11b⁺CD45⁺Ly6G^- monocytes and Ly6C^lowCD45⁺F4/80⁺ macrophages to pro-inflammatory Ly6C^highCD11b⁺CD45⁺Ly6G^- monocytes and Ly6C^highCD45⁺F4/80⁺ cells in blood, lungs and bronchoalveolar lavage fluid (BALF). Pro-inflammatory mediators and phenotypes were elevated and uteroglobin neutralization led to further increase. Enhanced total protein levels in BALF suggests leakage of respiratory epithelium. In vitro, uteroglobin inhibited the migratory capacity of monocytes and the TGF-β1 expression without affecting the viability. These results highlight an important role of endogenous uteroglobin as an intrinsic anti-inflammatory signal upon sepsis-induced early lung injury, which modulates the early monocyte/macrophages driven inflammation.