Incidence of acute respiratory distress syndrome and associated mortality in a polytrauma population

TBI related death has become the new epidemic in polytrauma: a 10-year prospective cohort analysis in severely injured patients

INTRODUCTION

Advances in trauma care have attributed to a decrease in mortality and change in cause of death. Consequently, exsanguination and traumatic brain injury (TBI) have become the most common causes of death. Exsanguination decreased by early hemorrhage control strategies, whereas TBI has become a global health problem. The aim of this study was to investigate trends in injury severity,physiology, treatment and mortality in the last decade.

METHODS

In 2014, a prospective cohort study was started including consecutive severely injured trauma patients > 15 years admitted to a Level-1 Trauma Center ICU. Demographics, physiology, resuscitation, and outcome parameters were prospectively collected.

RESULTS

Five hundred and seventy-eight severely injured patients with predominantly blunt injuries (94%) were included. Seventy-two percent were male with a median age of 46 (28-61) years, and ISS of 29 (22-38). Overall mortality rate was 18% (106/578) with TBI (66%, 70/106) being the largest cause of death. Less than 1% (5/578) died of exsanguination. Trend analysis of the 10-year period revealed similar mortality rates despite an ISS increase in the last 2 years. No significant differences in demographics,and physiology in ED were noted. Resuscitation strategy changed to less crystalloids and more FFP. Risk factors for mortality were age, brain injury severity, base deficit, hypoxia, and crystalloid resuscitation.

DISCUSSION

TBI was the single largest cause of death in severely injured patients in the last decade. With an aging population TBI will increase and become the next epidemic in trauma. Future research should focus on brain injury prevention and decreasing the inflammatory response in brain tissue causing secondary damage, as was previously done in other parts of the body.

The Ambivalent Role of miRNA-21 in Trauma and Acute Organ Injury

Since their initial recognition, miRNAs have been the subject of rising scientific interest. Especially in recent years, miRNAs have been recognized to play an important role in the mediation of various diseases, and further, their potential as biomarkers was recognized. Rising attention has also been given to miRNA-21, which has proven to play an ambivalent role as a biomarker. Responding to the demand for biomarkers in the trauma field, the present review summarizes the contrary roles of miRNA-21 in acute organ damage after trauma with a specific focus on the role of miRNA-21 in traumatic brain injury, spinal cord injury, cardiac damage, lung injury, and bone injury. This review is based on a PubMed literature search including the terms "miRNA-21" and "trauma", "miRNA-21" and "severe injury", and "miRNA-21" and "acute lung respiratory distress syndrome". The present summary makes it clear that miRNA-21 has both beneficial and detrimental effects in various acute organ injuries, which precludes its utility as a biomarker but makes it intriguing for mechanistic investigations in the trauma field.

Pulmonary miRNA expression after polytrauma depends on the surgical invasiveness and displays an anti-inflammatory pattern by the combined inhibition of C5 and CD14

Background

Respiratory failure can be a severe complication after polytrauma. Extensive systemic inflammation due to surgical interventions, as well as exacerbated post-traumatic immune responses influence the occurrence and progression of respiratory failure. This study investigated the effect of different surgical treatment modalities as well as combined inhibition of the complement component C5 and the toll-like receptor molecule CD14 (C5/CD14 inhibition) on the pulmonary microRNA (miRNA) signature after polytrauma, using a translational porcine polytrauma model.

Methods

After induction of general anesthesia, animals were subjected to polytrauma, consisting of blunt chest trauma, bilateral femur fractures, hemorrhagic shock, and liver laceration. One sham group (n=6) and three treatment groups were defined; Early Total Care (ETC, n=8), Damage Control Orthopedics (DCO, n=8), and ETC + C5/CD14 inhibition (n=4). Animals were medically and operatively stabilized, and treated in an ICU setting for 72 h. Lung tissue was sampled, miRNAs were isolated, transcribed, and pooled for qPCR array analyses, followed by validation in the individual animal population. Lastly, mRNA target prediction was performed followed by functional enrichment analyses.

Results

The miRNA arrays identified six significantly deregulated miRNAs in lung tissue. In the DCO group, miR-129, miR-192, miR-194, miR-382, and miR-503 were significantly upregulated compared to the ETC group. The miRNA expression profiles in the ETC + C5/CD14 inhibition group approximated those of the DCO group. Bioinformatic analysis revealed mRNA targets and signaling pathways related to alveolar edema, pulmonary fibrosis, inflammation response, and leukocytes recruitment. Collectively, the DCO group, as well as the ETC + C5/CD14 inhibition group, revealed more anti-inflammatory and regenerative miRNA expression profiles.

Conclusion

This study showed that reduced surgical invasiveness and combining ETC with C5/CD14 inhibition can contribute to the reduction of pulmonary complications.

Feasibility of high-frequency percussions in people with severe acquired brain injury and tracheostomy: an observational study

People with severe acquired brain injury (pwSABI) frequently experience pulmonary complications. Among these, atelectasis can occur as a result of pneumonia, thus increasing the chance of developing acute respiratory failure. Respiratory physiotherapy contribution to the management of atelectasis in pwSABI is yet poorly understood. We conducted a retrospective analysis on 15 non-cooperative pwSABI with tracheostomy and spontaneously breathing, hospitalized and treated with high-frequency percussion physiotherapy between September 2018 and February 2021 at the Neurological Rehabilitation Unit of the IRCCS "S.Maria Nascente - Fondazione Don Gnocchi", Milan. Our primary aim was to investigate the feasibility of such a physiotherapy intervention method. Then, we assessed changes in respiratory measures (arterial blood gas analysis and peripheral night-time oxygen saturation) and high-resolution computed tomography lung images, evaluated before and after the physiotherapy treatment. The radiological measures were a modified radiological atelectasis score (mRAS) assigned by two radiologists, and an opacity score automatically provided by the software CT Pneumonia Analysis® that identifies the regions of abnormal lung patterns. Treatment diaries showed that all treatments were completed, and no adverse events during treatment were registered. Among the 15 pwSABI analyzed, 8 were treated with IPV® and 7 with MetaNeb®. After a median of 14 (I-III quartile=12.5-14.5) days of treatment, we observed a statistical improvement in various arterial blood gas measures and peripheral night-time oxygen saturation measures. We also found radiological improvement or stability in more than 80% of pwSABI. In conclusion, our physiotherapy approach was feasible, and we observed respiratory parameters and radiological improvements. Using technology to assess abnormal tomographic patterns could be of interest to disentangle the short-term effects of respiratory physiotherapy on non-collaborating people.

Effect of Injury Patterns on the Development of Complications and Trauma-Induced Mortality in Patients Suffering Multiple Trauma

Patients that suffer from severe multiple trauma are highly vulnerable to the development of complications that influence their outcomes. Therefore, this study aimed to evaluate the risk factors that can facilitate an early recognition of adult patients at risk. The inclusion criteria were as follows: admission to a level 1 trauma center, injury severity score (ISS) ≥ 16 (severe injury was defined by an abbreviated injury score (AIS) ≥ 3) and ≥18 years of age. Injury- and patient-associated factors were correlated with the development of four complication clusters (surgery-related, infection, thromboembolic events and organ failure) and three mortality time points (immediate (6 h after admission), early (>6 h-72 h) and late (>72 h) mortality). Statistical analysis was performed using a Chi-square, Mann-Whitney U test, Cox hazard regression analysis and binominal logistic regression analysis. In total, 383 patients with a median ISS of 24 (interquartile range (IQR) 17-27) were included. The overall mortality rate (27.4%) peaked in the early mortality group. Lactate on admission significantly correlated with immediate and early mortality. Late mortality was significantly influenced by severe head injuries in patients with a moderate ISS (ISS 16-24). In patients with a high ISS (≥25), late mortality was influenced by a higher ISS, older age and higher rates of organ failure. Complications were observed in 47.5% of all patients, with infections being seen most often. The development of complications was significantly influenced by severe extremity injuries, the duration of mechanical ventilation and length of ICU stay. Infection remains the predominant posttraumatic complication. While immediate and early mortality is mainly influenced by the severity of the initial trauma, the rates of severe head injuries influence late mortality in moderate trauma severity, while organ failure remains a relevant factor in patients with a high injury severity.

Longitudinal assessment of the inflammatory response: The next step in personalized medicine after severe trauma

Infections in trauma patients are an increasing and substantial cause of morbidity, contributing to a mortality rate of 5-8% after trauma. With increased early survival rates, up to 30-50% of multitrauma patients develop an infectious complication. Trauma leads to a complex inflammatory cascade, in which neutrophils play a key role. Understanding the functions and characteristics of these cells is important for the understanding of their involvement in the development of infectious complications. Recently, analysis of neutrophil phenotype and function as complex biomarkers, has become accessible for point-of-care decision making after trauma. There is an intriguing relation between the neutrophil functional phenotype on admission, and the clinical course (e.g., infectious complications) of trauma patients. Potential neutrophil based cellular diagnostics include subsets based on neutrophil receptor expression, responsiveness of neutrophils to formyl-peptides and FcγRI (CD64) expression representing the infectious state of a patient. It is now possible to recognize patients at risk for infectious complications when presented at the trauma bay. These patients display increased numbers of neutrophil subsets, decreased responsiveness to fMLF and/or increased CD64 expression. The next step is to measure these biomarkers over time in trauma patients at risk for infectious complications, to guide decision making regarding timing and extent of surgery and administration of (preventive) antibiotics.

Predictors of mortality in trauma patients with acute respiratory distress syndrome receiving extracorporeal membrane oxygenation

Objective

Trauma-related Acute Respiratory Distress Syndrome (TR-ARDS) mortality ranges from 30 to 80%. Extracorporeal membrane oxygenation (ECMO) has demonstrated a survival benefit in select cases of TR-ARDS. In order to provide improved patient selection, we evaluated predictors of mortality in TR-ARDS patients receiving ECMO, hypothesizing age and severe thoracic trauma as risk factors for mortality.

Methods

The Trauma Quality Improvement Program (2010-2016) was queried for patients ≥ 18-years-old with TR-ARDS receiving ECMO. Survivors were compared to those who died. A multivariable logistic regression model was used for analysis and included covariates known to increase risk of mortality in trauma patients.

Results

From 362 TR-ARDS patients on ECMO, 226 (62.4%) survived and 136 (37.6%) died. Those who died were older (median, 28 vs. 24-years-old, p = 0.036) and had a higher injury severity score (29 vs. 26, p = 0.040) than survivors. After adjusting for covariates, independent predictors of mortality included a severe head (OR=2.66, CI=1.29-5.49, p = 0.008) and thorax (OR =3.52, CI=1.96-6.33, p < 0.001) injury. Age ≥ 65-years-old was not a predictor of mortality (p = 0.432).

Discussion

Age ≥ 65 years did not appear to increase the risk of mortality in patients with TR-ARDS receiving ECMO. However, those with severe head or thorax injury had more than a two-fold and three-fold increased risk of death, respectively. TR-ARDS patients differ from medical ARDS patients in terms of etiology, age and injuries. Thus, prior pre-ECMO mortality prediction models may lack predictive capability for trauma patients. Future prospective studies are needed to confirm our findings and develop guidelines for utilization of ECMO for trauma patients.

Early Plasma Nuclear DNA, Mitochondrial DNA, and Nucleosome Concentrations Are Associated With Acute Kidney Injury in Critically Ill Trauma Patients

Circulating nucleic acids, alone and in complex with histones as nucleosomes, have been proposed to link systemic inflammation and coagulation after trauma to acute kidney injury (AKI). We sought to determine the association of circulating nucleic acids measured at multiple time points after trauma with AKI risk.

Prevalence and Outcome of Acute Respiratory Distress Syndrome in Traumatic Brain Injury: A Systematic Review and Meta-Analysis

OBJECTIVES

Acute respiratory distress syndrome (ARDS) in patients with traumatic brain injury (TBI) is associated with increased mortality. Information on the prevalence of ARDS and its neurological outcome after TBI is sparse. We aimed to systematically review the prevalence, risk factors, and outcome of ARDS in TBI population.

DATA SOURCES

PubMed and four other databases (Embase, Cochrane Library, Web of Science Core Collection, and Scopus) from inception to July 6, 2020.

STUDY SELECTION

Randomized controlled trials (RCTs) and observational studies in patients older than 18 years old.

DATA EXTRACTION

Two independent reviewers extracted the data. Study quality was assessed by the Cochrane Risk of Bias tool for RCTs, the Newcastle-Ottawa Scale for cohort and case-control studies. Good neurological outcome was defined as Glasgow Outcome Scale ≥ 4. Random-effects meta-analyses were conducted to estimate pooled outcome prevalence and their 95% confidence intervals (CI).

DATA SYNTHESIS

We included 20 studies (n = 2830) with median age of 44 years (interquartile range [IQR] = 35-47, 64% male) and 79% (n = 2237) suffered severe TBI. In meta-analysis, 19% patients (95% CI = 0.13-0.27, I2 = 93%) had ARDS after TBI. The median time from TBI to ARDS was 3 days (IQR = 2-5). Overall survival at discharge for the TBI cohort was 70% (95% CI = 0.64-0.75; I2 = 85%) and good neurological outcome at any time was achieved in 31% of TBI patients (95% CI = 0.23-0.40; I2 = 88%). TBI cohort without ARDS had higher survival (67% vs. 57%, p = 0.01) and good neurological outcomes (34% vs. 23%, p = 0.02) compared to those with ARDS. We did not find any specific risk factors for developing ARDS.

CONCLUSION

In this meta-analysis, approximately one in five patients had ARDS shortly after TBI with the median time of 3 days. The presence of ARDS was associated with worse neurological outcome and mortality in TBI. Further research on prevention and intervention strategy of TBI-associated ARDS is warranted.

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.

Berberine administrated with different routes attenuates inhaled LPS-induced acute respiratory distress syndrome through TLR4/NF-κB and JAK2/STAT3 inhibition

Accumulating evidence showed that berberine possessed the anti-inflammatory action in various diseases caused by inflammation. However, it was still unclear whether both inhalation and injection with berberine produced pulmonary protective role in acute respiratory distress syndrome (ARDS). This study was aimed to evaluate the effects of both administration routes including inhalation and injection with berberine in ARDS induced by lipopolysaccharide (LPS) inhalation. Histopathological examination and weight of lung were evaluated. Phosphorylation of NF-κB, JAK2 and STAT3 were measured to assess the activity of inflammation related signaling pathways. Proinflammatory cytokines including interleukin (IL)-1β and tumor necrosis factor (TNF)-α in the bronchoalveolar lavage fluid (BALF) and serum were also detected. The results showed that LPS caused the lung injury, while both administration routes with berberine attenuated the injury and improved the pulmonary morphology. In addition, the primary TLR4/NF-κB and secondary JAK2/STAT3 signaling pathways which were activated by LPS in lung were totally inhibited by berberine administration. Moreover, proinflammatory cytokines in both BALF and serum were decreased by berberine. Considering that molecular docking simulation indicated that berberine could bind with TLR4, the present suggested that the inhibition of the inflammation related TLR4/NF-κB and JAK2/STAT3 signaling pathways might be involved in the pulmonary protective effect of berberine in LPS-induced ARDS.

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.

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.

Dilemma of crystalloid resuscitation in non-exsanguinating polytrauma: what is too much?

Background

Aggressive crystalloid resuscitation increases morbidity and mortality in exsanguinating patients. Polytrauma patients with severe tissue injury and subsequent inflammatory response without major blood loss also need resuscitation. This study investigated crystalloid and blood product resuscitation in non-exsanguinating polytrauma patients and studied possible adverse outcomes.

Methods

A 6.5-year prospective cohort study included consecutive trauma patients admitted to a Level 1 Trauma Center intensive care unit (ICU) who survived 48 hours. Demographics, physiologic and resuscitation parameters in first 24 hours, Denver Multiple Organ Failure scores, adult respiratory distress syndrome (ARDS) data and infectious complications were prospectively collected. Patients were divided in 5 L crystalloid volume subgroups (0–5, 5–10, 10–15 and >15 L) to make clinically relevant comparisons. Data are presented as median (IQR); p value <0.05 was considered significant.

Results

367 patients (70% men) were included with median age of 46 (28–61) years, median Injury Severity Score was 29 (22–35) and 95% sustained blunt injuries. 17% developed multiple organ dysfunction syndrome (MODS), 4% ARDS and 14% died. Increasing injury severity, acidosis and coagulopathy were associated with more crystalloid administration. Increasing crystalloid volumes were associated with more blood products, increased ventilator days, ICU length of stay, hospital length of stay, MODS, infectious complications and mortality rates. Urgent laparotomy was found to be the most important independent predictor for crystalloid resuscitation in multinominal regression analysis. Further, fresh frozen plasma (FFP) <8 hours was less likely to be administered in patients >5 L compared with the group 0–5 L. With increasing crystalloid volume, the adjusted odds of MODS, ARDS and infectious complications increased 3–4-fold, although not statistically significant. Mortality increased 6-fold in patients who received >15 L crystalloids (p=0.03).

Discussion

Polytrauma patients received large amounts of crystalloids with few FFPs <24 hours. In patients with <10 L crystalloids, <24-hour mortality and MODS rates were not influenced by crystalloid resuscitation. Mortality increased 6-fold in patients who received >15 L crystalloids ≤24 hours. Efforts should be made to balance resuscitation with modest crystalloids and sufficient amount of FFPs.

Level of evidence

Level 3.

Study type

Population-based cohort study.

Knockdown of lncRNA MALAT1 Alleviates LPS-Induced Acute Lung Injury via Inhibiting Apoptosis Through the miR-194-5p/FOXP2 Axis

Purpose

We aimed to identify and verify the key genes and lncRNAs associated with acute lung injury (ALI) and explore the pathogenesis of ALI. Research showed that lower expression of the lncRNA metastasis-associated lung carcinoma transcript 1 (MALAT1) alleviates lung injury induced by lipopolysaccharide (LPS). Nevertheless, the mechanisms of MALAT1 on cellular apoptosis remain unclear in LPS-stimulated ALI. We investigated the mechanism of MALAT1 in modulating the apoptosis of LPS-induced human pulmonary alveolar epithelial cells (HPAEpiC).

Methods

Differentially expressed lncRNAs between the ALI samples and normal controls were identified using gene expression profiles. ALI-related genes were determined by the overlap of differentially expressed genes (DEGs), genes correlated with lung, genes correlated with key lncRNAs, and genes sharing significantly high proportions of microRNA targets with MALAT1. Quantitative real-time PCR (qPCR) was applied to detect the expression of MALAT1, microRNA (miR)-194-5p, and forkhead box P2 (FOXP2) mRNA in 1 μg/ml LPS-treated HPAEpiC. MALAT1 knockdown vectors, miR-194-5p inhibitors, and ov-FOXP2 were constructed and used to transfect HPAEpiC. The influence of MALAT1 knockdown on LPS-induced HPAEpiC proliferation and apoptosis via the miR-194-5p/FOXP2 axis was determined using Cell counting kit-8 (CCK-8) assay, flow cytometry, and Western blotting analysis, respectively. The interactions between MALAT1, miR-194-5p, and FOXP2 were verified using dual-luciferase reporter gene assay.

Results

We identified a key lncRNA (MALAT1) and three key genes (EYA1, WNT5A, and FOXP2) that are closely correlated with the pathogenesis of ALI. LPS stimulation promoted MALAT1 expression and apoptosis and also inhibited HPAEpiC viability. MALAT1 knockdown significantly improved viability and suppressed the apoptosis of LPS-stimulated HPAEpiC. Moreover, MALAT1 directly targeted miR-194-5p, a downregulated miRNA in LPS-stimulated HPAEpiC, when FOXP2 was overexpressed. MALAT1 knockdown led to the overexpression of miR-194-5p and restrained FOXP2 expression. Furthermore, inhibition of miR-194-5p exerted a rescue effect on MALAT1 knockdown of FOXP2, whereas the overexpression of FOXP2 reversed the effect of MALAT1 knockdown on viability and apoptosis of LPS-stimulated HPAEpiC.

Conclusion

Our results demonstrated that MALAT1 knockdown alleviated HPAEpiC apoptosis by competitively binding to miR-194-5p and then elevating the inhibitory effect on its target FOXP2. These data provide a novel insight into the role of MALAT1 in the progression of ALI and potential diagnostic and therapeutic strategies for ALI patients.

Global changes in mortality rates in polytrauma patients admitted to the ICU-a systematic review

Background

Many factors of trauma care have changed in the last decades. This review investigated the effect of these changes on global all-cause and cause-specific mortality in polytrauma patients admitted to the intensive care unit (ICU). Moreover, changes in trauma mechanism over time and differences between continents were analyzed.

Main body

A systematic review of literature on all-cause mortality in polytrauma patients admitted to ICU was conducted. All-cause and cause-specific mortality rates were extracted as well as trauma mechanism of each patient. Poisson regression analysis was used to model time trends in all-cause and cause-specific mortality.

Thirty studies, which reported mortality rates for 82,272 patients, were included and showed a decrease of 1.8% (95% CI 1.6–2.0%) in all-cause mortality per year since 1966. The relative contribution of brain injury-related death has increased over the years, whereas the relative contribution of death due to multiple organ dysfunction syndrome (MODS), acute respiratory distress syndrome, and sepsis decreased. MODS was the most common cause of death in North America, and brain-related death was the most common in Asia, South America, and Europe. Penetrating trauma was most often reported in North America and Asia.

Conclusions

All-cause mortality in polytrauma patients admitted to the ICU has decreased over the last decades. A shift from MODS to brain-related death was observed. Geographical differences in cause-specific mortality were present, which may provide region-specific learning possibilities resulting in improvement of global trauma care.

Inflammation, Thrombosis, and Destruction: The Three-Headed Cerberus of Trauma- and SARS-CoV-2-Induced ARDS

Physical trauma can be considered an unrecognized "pandemic" because it can occur anywhere and affect anyone and represents a global burden. Following severe tissue trauma, patients frequently develop acute lung injury (ALI) and/or acute respiratory distress syndrome (ARDS) despite modern surgical and intensive care concepts. The underlying complex pathophysiology of life-threatening ALI/ARDS has been intensively studied in experimental and clinical settings. However, currently, the coronavirus family has become the focus of ALI/ARDS research because it represents an emerging global public health threat. The clinical presentation of the infection is highly heterogeneous, varying from a lack of symptoms to multiple organ dysfunction and mortality. In a particular subset of patients, the primary infection progresses rapidly to ALI and ARDS. The pathophysiological mechanisms triggering and driving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced ALI/ARDS are still poorly understood. Although it is also generally unknown whether insights from trauma-induced ARDS may be readily translated to SARS-CoV-2-associated ARDS, it was still recommended to treat coronavirus-positive patients with ALI/ARDS with standard protocols for ALI/ARDS. However, this strategy was questioned by clinical scientists, because it was documented that some severely hypoxic SARS-CoV-2-infected patients exhibited a normal respiratory system compliance, a phenomenon rarely observed in ARDS patients with another underlying etiology. Therefore, coronavirus-induced ARDS was defined as a specific ARDS phenotype, which accordingly requires an adjusted therapeutic approach. These suggestions reflect previous attempts of classifying ARDS into different phenotypes that might overall facilitate ARDS diagnosis and treatment. Based on the clinical data from ARDS patients, two major phenotypes have been proposed: hyper- and hypo-inflammatory. Here, we provide a comparative review of the pathophysiological pathway of trauma-/hemorrhagic shock-induced ARDS and coronavirus-induced ARDS, with an emphasis on the crucial key points in the pathogenesis of both these ARDS forms. Therefore, the manifold available data on trauma-/hemorrhagic shock-induced ARDS may help to better understand coronavirus-induced ARDS.

Cigarette Smoking and ARDS After Blunt Trauma: The Influence of Changing Smoking Patterns and Resuscitation Practices

BACKGROUND

Cigarette smoking is associated with an increased risk of developing ARDS. However, whether changes in smoking patterns or processes of care impact this relationship is unclear.

RESEARCH QUESTION

Are changes in smoking and resuscitation patterns associated with changes in the relationship between smoking and ARDS?

STUDY DESIGN AND METHODS

We conducted a prospective cohort study of critically injured adults with blunt trauma from 2005 to 2015. Plasma cotinine, a tobacco biomarker, was measured to categorize patients by smoking status. We used regression to assess the relationship between smoking, resuscitation practices, and ARDS over time.

RESULTS

In the overall cohort, active (OR, 1.9; 95% CI, 1.0-3.5; P = .046) and passive (OR, 2.6; 95% CI, 1.4-4.8; P = .002) smoking were associated with an increased risk of developing ARDS in multivariate analyses. In contrast to the dose-response relationship in patients enrolled from 2005 to 2008, passive cigarette smoke exposure was associated with the highest risk of developing ARDS in patients enrolled from 2009 to 2015, suggesting a threshold effect. Packed RBC (pRBC) and fresh frozen plasma (FFP) transfusions were associated with an increased risk of developing ARDS, particularly in active smokers (pRBC: OR, 5.6; P < .001; FFP: OR, 4.5; P < .001) compared with passive smokers or nonsmokers. Blood product transfusion and smoking patterns changed over time.

INTERPRETATION

Despite changes in resuscitation and smoking patterns, cigarette smoking remains associated with an increased risk of developing ARDS. However, this relationship changed over time, with passive smokers at particularly increased risk of developing ARDS in later years, which may be related to changes in smoking patterns or transfusion practices over time. These findings highlight the need for additional mechanistic and epidemiologic studies of the effects of low levels of cigarette smoke exposure on lung health.

Practical approach to respiratory emergencies in neurological diseases

Many neurological diseases may cause acute respiratory failure (ARF) due to involvement of bulbar respiratory center, spinal cord, motoneurons, peripheral nerves, neuromuscular junction, or skeletal muscles. In this context, respiratory emergencies are often a challenge at home, in a neurology ward, or even in an intensive care unit, influencing morbidity and mortality. More commonly, patients develop primarily ventilatory impairment causing hypercapnia. Moreover, inadequate bulbar and expiratory muscle function may cause retained secretions, frequently complicated by pneumonia, atelectasis, and, ultimately, hypoxemic ARF. On the basis of the clinical onset, two main categories of ARF can be identified: (i) acute exacerbation of chronic respiratory failure, which is common in slowly progressive neurological diseases, such as movement disorders and most neuromuscular diseases, and (ii) sudden-onset respiratory failure which may develop in rapidly progressive neurological disorders including stroke, convulsive status epilepticus, traumatic brain injury, spinal cord injury, phrenic neuropathy, myasthenia gravis, and Guillain-Barré syndrome. A tailored assistance may include manual and mechanical cough assistance, noninvasive ventilation, endotracheal intubation, invasive mechanical ventilation, or tracheotomy. This review provides practical recommendations for prevention, recognition, management, and treatment of respiratory emergencies in neurological diseases, mostly in teenagers and adults, according to type and severity of baseline disease.

Attenuation of MODS-related and ARDS-related mortality makes infectious complications a remaining challenge in the severely injured

Introduction

The recent decrease in multiple organ dysfunction syndrome (MODS)-associated and adult respiratory distress syndrome (ARDS)-associated mortality could be considered a success of improvements in trauma care. However, the incidence of infections remains high in patients with polytrauma, with high morbidity and hospital resources usage. Infectious complications might be a residual effect of the decrease in MODS-related/ARDS-related mortality. This study investigated the current incidence of infectious complications in polytrauma.

Methods

A 5.5-year prospective population-based cohort study included consecutive severely injured patients (age >15) admitted to a (Level-1) trauma center intensive care unit (ICU) who survived >48 hours. Demographics, physiologic and resuscitation parameters, multiple organ failure and ARDS scores, and infectious complications (pneumonia, fracture-related infection, meningitis, infections related to blood, wound, and urinary tract) were prospectively collected. Data are presented as median (IQR), p<0.05 was considered significant.

Results

297 patients (216 (73%) men) were included with median age of 46 (27–60) years, median Injury Severity Score was 29 (22–35), 96% sustained blunt injuries. 44 patients (15%) died. One patient (2%) died of MODS and 1 died of ARDS. 134 patients (45%) developed 201 infectious complications. Pneumonia was the most common complication (50%). There was no difference in physiologic parameters on arrival in emergency department and ICU between patients with and without infectious complications. Patients who later developed infections underwent more often a laparotomy (32% vs 18%, p=0.009), had more often pelvic fractures (38% vs 25%, p=0.02), and received more blood products <8 hours. They had more often MODS (25% vs 13%, p=0.005), stayed longer on the ventilator (10 (5–15) vs 5 (2–8) days, p<0.001), longer in ICU (11 (6–17) vs 6 (3–10) days, p<0.001), and in hospital (30 (20–44) vs 16 (10–24) days, p<0.001). There was however no difference in mortality (12% vs 17%, p=0.41) between both groups.

Conclusion

45% of patients developed infectious complications. These patients had similar mortality rates, but used more hospital resources. With low MODS-related and ARDS-related mortality, infections might be a residual effect, and are one of the remaining challenges in the treatment of patients with polytrauma.

Level of evidence

Level 3.

Study type

Population-based cohort study.

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.

The evolution of trauma care in the Netherlands over 20 years

Introduction

In 1999 an inclusive trauma system was initiated in the Netherlands and a nationwide trauma registry, including all admitted trauma patients to every hospital, was started. The Dutch trauma system is run by trauma surgeons who treat both the truncal (visceral) and extremity injuries (fractures).

Materials and Methods

In this comprehensive review based on previous published studies, data over the past 20 years from the central region of the Netherlands (Utrecht) was evaluated.

Results

It is demonstrated that the initiation of the trauma systems and the governance by the trauma surgeons led to a region-wide mortality reduction of 50% and a mortality reduction for the most severely injured of 75% in the level 1 trauma centre. Furthermore, major improvements were found in terms of efficiency, demonstrating the quality of the current system and its constructs such as the type of surgeon. Due to the major reduction in mortality over the past few years, the emphasis of trauma care evaluation shifts towards functional outcome of severely injured patients. For the upcoming years, centralisation of severely injured patients should also aim at the balance between skills in primary resuscitation and surgical stabilization versus longitudinal surgical involvement.

Conclusion

Further centralisation to a limited number of level 1 trauma centres in the Netherlands is necessary to consolidate experience and knowledge for the trauma surgeon. The future trauma surgeon, as specialist for injured patients, should be able to provide the vast majority of trauma care in this system. For the remaining part, intramural, regional and national collaboration is essential

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.

Is chest imaging relevant in diagnosing acute respiratory distress syndrome in polytrauma patients? A population-based cohort study

Purpose

The definition of acute respiratory distress syndrome (ARDS) has often been modified with Berlin criteria being the most recent. ARDS is divided into three categories based on the degree of hypoxemia using PaO₂/FiO₂ ratio. Radiological findings are standardized with bilateral diffuse pulmonary infiltrates present on chest imaging. This study investigated whether chest imaging is relevant in diagnosing ARDS in polytrauma patients.

Methods

The 5-year prospective study included consecutive trauma patients admitted to a Level-1 Trauma Center ICU. Demographics, ISS, physiologic parameters, resuscitation parameters, and ARDS data were prospectively collected. Acute hypoxic respiratory failure (AHRF) was categorized as Berlin criteria without bilateral diffuse pulmonary infiltrates on imaging. Data are presented as median (IQR), p < 0.05 was considered significant.

Results

267 patients were included. Median age was 45 (26–59) years, 199 (75%) males, ISS was 29 (22–35), 258 (97%) patients had blunt injuries. Thirty-five (13%) patients died. 192 (72%) patients developed AHRF. AHRF patients were older, more often male, had higher ISS, needed more crystalloids and blood products than patients without AHRF. They developed more pulmonary complications, stayed longer on the ventilator, in ICU and in hospital, and died more often. Fifteen (6%) patients developed ARDS. There was no difference in outcome between ARDS and AHRF patients.

Conclusions

Many patients developed AHRF and only a few ARDS. Patients with similar hypoxemia without bilateral diffuse pulmonary infiltrates had comparable outcome as ARDS patients. Chest imaging did not influence the outcome. Large-scale multicenter validation of ARDS criteria is warranted to investigate whether diffuse bilateral pulmonary infiltrates on chest imaging could be omitted as a mandatory part of the definition of ARDS in polytrauma patients.

Electronic supplementary material

The online version of this article (10.1007/s00068-019-01204-3) contains supplementary material, which is available to authorized users.

Neutrophil heterogeneity and its role in infectious complications after severe trauma

Background

Trauma leads to a complex inflammatory cascade that induces both immune activation and a refractory immune state in parallel. Although both components are deemed necessary for recovery, the balance is tight and easily lost. Losing the balance can lead to life-threatening infectious complications as well as long-term immunosuppression with recurrent infections. Neutrophils are known to play a key role in these processes. Therefore, this review focuses on neutrophil characteristics and function after trauma and how these features can be used to identify trauma patients at risk for infectious complications.

Results

Distinct neutrophil subtypes exist that play their own role in the recovery and/or development of infectious complications after trauma. Furthermore, the refractory immune state is related to the risk of infectious complications. These findings change the initial concepts of the immune response after trauma and give rise to new biomarkers for monitoring and predicting inflammatory complications in severely injured patients.

Conclusion

For early recognition of patients at risk, the immune system should be monitored. Several neutrophil biomarkers show promising results and analysis of these markers has become accessible to such extent that they can be used for point-of-care decision making after trauma.