Lung Contusion in Polytrauma: An Analysis of the TraumaRegister DGU

Effects of Different Treatment Modalities on Lung Injury in Experimental Pulmonary Contusion Model

INTRODUCTION

The study experimentally evaluated the efficacies of different agents in treating pulmonary contusion.

METHODS

In our study, 42 Wistar albino rats were divided into six groups of seven animals each. A model of lung contusion with blunt chest trauma was performed in five groups, except for the control group. One group with pulmonary contusion was considered an untreated group, and saline was administered. For other groups, prednisolone, tranexamic acid, N-acetylcysteine, and vitamin E were applied to determine their efficacy in treatment. The rats were sacrificed 24 h after trauma, and their injured lungs were collected for histopathological examination and blood samples for blood gas analysis. Histopathologically, bronchial damage, alveolar hemorrhage, emphysema, and leukocyte infiltration were assessed using the scoring system.

RESULTS

In our study, statistically significant differences were detected between the rat groups in terms of intraalveolar hemorrhage, leukocyte infiltration, and bronchial damage. In post hoc analysis, intraalveolar hemorrhage was significantly higher in the untreated group compared to the control group (P = 0.012). A near-significant difference was observed between the untreated group and the N-acetylcysteine group (P = 0.061). Regarding leukocyte infiltration, the tranexamic acid group showed significantly higher values compared to both the prednisolone and control groups (P = 0.007; P = 0.016, respectively). For bronchial damage, the levels observed in the vitamin E and tranexamic acid groups were significantly higher than those in the control group (P = 0.08 and P = 0.037, respectively).

CONCLUSIONS

Many agents are used to treat pulmonary contusion, but no gold standard treatment exists. Prednisolone and N-acetylcysteine play significant roles in treatment. These two drugs contributed to the regression of the findings in pulmonary contusion treatment.

Predicting life-threatening hemoptysis in traumatic pulmonary parenchymal injury using computed tomography semi-automated lung volume quantification

OBJECTIVES

Chest computed tomography (CT) can diagnose and assess the severity of pulmonary contusions. However, in cases of severe lung contusion, the total lung volume ratio may not accurately predict severity. This study investigated the association between life-threatening hemoptysis and chest CT imaging data on arrival at the emergency department in patients with pulmonary contusions or lacerations due to blunt chest injury.

METHODS

The records of 277 patients with lung contusions or lacerations treated at a trauma center between 2018 and 2022 were retrospectively reviewed. The ratio of the local lung contusion volume to lobe volume in each lobe was calculated from chest CT images. The maximal ratio in the Hounsfield unit (HU) range was defined as the highest ratio value within the HU range among five lobes.

RESULTS

The median patient age was 41 years, and 68.6% were male. Life-threatening hemoptysis occurred in 39 patients. The area under the receiver operating characteristic curve for the maximal ratio at -500 HU to 100 HU was 96.52%. The cutoff value was 45.49%. Multivariate analysis showed a high maximal chest CT ratio ≥ 45.49% at -500 HU to 100 HU (adjusted odds ratio [aOR]: 104.66, 95% confidence interval [CI]: 21.81-502.16, p < 0.001), hemopneumothorax (aOR: 5.18, 95% CI: 1.25-21.47, p = 0.023), and chest abbreviated injury scale (AIS, aOR: 5.58, 95% CI: 1.68-18.57, p = 0.005) were associated with life-threatening hemoptysis.

CONCLUSIONS

Maximal chest CT ratios ≥ 45.49% at -500 HU to 100 HU, hemopneumothorax, and high chest AIS scores are associated with life-threatening hemoptysis in patients with blunt chest trauma.

CRITICAL RELEVANCE STATEMENT

The present study provides an objective index derived from chest CT images to predict the occurrence of life-threatening hemoptysis. This information helps screen high-risk patients in need of more intensive monitoring for early intervention to improve outcomes.

KEY POINTS

Emergency department CT helps predict life-threatening hemoptysis in patients with lung contusions. Maximal CT ratios ≥ 45.49% (-500 HU to 100 HU, either lung lobe) are associated with life-threatening hemoptysis. High chest abbreviated injury scale scores and hemopneumothorax also predict life-threatening hemoptysis.

Improved Discriminability of Severe Lung Injury and Atelectasis in Thoracic Trauma at Low keV Virtual Monoenergetic Images from Photon-Counting Detector CT

Objectives: To evaluate the value of virtual monoenergetic images (VMI) from photon-counting detector CT (PCD-CT) for discriminability of severe lung injury and atelectasis in polytraumatized patients. Materials & Methods: Contrast-enhanced PCD-CT examinations of 20 polytraumatized patients with severe thoracic trauma were included in this retrospective study. Spectral PCD-CT data were reconstructed using a noise-optimized virtual monoenergetic imaging (VMI) algorithm with calculated VMIs ranging from 40 to 120 keV at 10 keV increments. Injury-to-atelectasis contrast-to-noise ratio (CNR) was calculated and compared at each energy level based on CT number measurements in severely injured as well as atelectatic lung areas. Three radiologists assessed subjective discriminability, noise perception, and overall image quality. Results: CT values for atelectasis decreased as photon energy increased from 40 keV to 120 keV (mean Hounsfield units (HU): 69 at 40 keV; 342 at 120 keV), whereas CT values for severe lung injury remained near-constant from 40 keV to 120 keV (mean HU: 42 at 40 keV; 44 at 120 keV) with significant differences at each keV level (p < 0.001). The optimal injury-to-atelectasis CNR was observed at 40 keV in comparison with the remaining energy levels (p < 0.001) except for 50 keV (p > 0.05). In line with this, VMIs at 40 keV were rated best regarding subjective discriminability. VMIs at 60-70 keV, however, provided the highest subjective observer parameters regarding subjective image noise as well as image quality. Conclusions: Discriminability between severely injured and atelectatic lung areas after thoracic trauma can be substantially improved by virtual monoenergetic imaging from PCD-CT with superior contrast and visual discriminability at 40-50 keV.

Influence of Age on Outcome Following Rib Fractures - A Case-Control Analysis

Background

Thoracic injuries are a very common entity throughout all age groups. With rising numbers of geriatric patients, characteristics of this patient group need to be better defined. The aim of this study was to investigate the impact of age on the outcome of thoracic trauma. In this project we provide a stratification of differentiated age groups regarding outcome parameter on rib fractures.

Methods

The study employed a retrospective design using data from patients who sustained thoracic trauma and received treatment at a level I trauma center over a 5-year period. Patients with the same pattern of injury and gender but different age (above and below 70 years) were matched.

Results

The mean age of the study population was 57 ± 19 years, 69% were male, 54% of patients had preexisting comorbidities. Hemothorax was present in 109 (16%), pneumothorax in 204 (31%) and lung contusions in 136 patients (21%). The overall complication rate was 36%, with a mortality rate of 10%. The matched pair analysis of 70 pairs revealed a higher prevalence of comorbidities in the older age group. They had significantly fewer pulmonary contusions and pneumothoraces than the younger patients and a shorter length of stay. However, the older age group had a significantly higher mortality rate.

Conclusions

Geriatric patients with rib fractures exhibit different patterns of intrathoracic injuries compared to their younger counterparts. Although numeric age may not be the most accurate predictor of adverse outcome, we found that higher age was associated with a clear trend towards an increased mortality rate. Our findings build a basis for further research to evaluate the outcome of age for instance with the tool of a rib fracture scoring system within stratified age groups in order to identify patients at major risk.

Lactate dehydrogenase can be used for differential diagnosis to identify patients with severe polytrauma with or without chest injury-A retrospective study

BACKGROUND

Chest injury is an important factor regarding the prognosis of patients with polytrauma (PT), and the rapid diagnosis of chest injury is of utmost importance. Therefore, the current study focused on patients' physiology and laboratory findings to quickly identify PT patients with chest injury.

METHOD

Data on 64 PT patients treated at a trauma center level I between June 2020 and August 2021 were retrospectively collected. The patients were divided into a PT group without chest injury (Group A) and a PT group including chest injury (Group B). The relationship between chest injury and the patients' baseline characteristics and biochemical markers was analyzed.

RESULTS

Heart rate, respiration rate, Sequential Organ Failure Assessment (SOFA) score, glutamate oxaloacetate aminotransferase (GOT), glutamate pyruvate transaminase (GPT), creatine kinase MB (CK-MB), leucocytes, hemoglobin (Hb), platelets, urine output, lactate, and lactate dehydrogenase (LDH) in groups A and B exhibited statistically significant differences at certain time points. Multifactorial analysis showed that blood LDH levels at admission were associated with chest injury (P = 0.039, CI 95% 1.001, 1.022).

CONCLUSION

LDH may be a promising indicator for screening for the presence of chest injury in patients with severe polytrauma.

High positive end-expiratory pressure ventilation mitigates the progression from unilateral pulmonary contusion to ARDS: An animal study

BACKGROUND

Pulmonary contusion (PC) is common in severely traumatized patients and can lead to respiratory failure requiring mechanical ventilation (MV). Ventilator-induced lung injury (VILI) might aggravate lung damage. Despite underrepresentation of trauma patients in trials on lung-protective MV, results are extrapolated to these patients, potentially disregarding important pathophysiological differences.

METHODS

Three MV protocols with different positive end-expiratory pressure (PEEP) levels: ARDSnetwork lower PEEP (ARDSnet-low), ARDSnetwork higher PEEP (ARDSnet-high), and open lung concept (OLC) were applied in swine for 24 hours following PC. Gas exchange, lung mechanics, quantitative computed tomography, and diffuse alveolar damage (DAD) score were analyzed. Results are given as median (interquartile range) at 24 hours. Statistical testing was performed using general linear models (group effect) over all measurement points and pairwise Mann-Whitney U tests for DAD.

RESULTS

There were significant differences between groups: PEEP ( p < 0.0001) ARDSnet-low (8 [8-10] cmH 2 O), ARDSnet-high (12 [12-12] cmH 2 O), OLC (21 [20-22] cmH 2 O). The fraction of arterial partial pressure of oxygen and inspired oxygen fraction ( p = 0.0016) was lowest in ARDSnet-low (78 (73-111) mm Hg) compared with ARDSnet-high (375 (365-423) mm Hg) and OLC (499 (430-523) mm Hg). The end-expiratory lung volume (EELV) differed significantly ( p < 0.0001), with highest values in OLC (64% [60-70%]) and lowest in ARDSnet-low (34% [24-37%]). Costa's surrogate for mechanical power differed significantly ( p < 0.0001), with lowest values for ARDSnet-high (73 [58-76]) compared with OLC (105 [108-116]). Diffuse alveolar damage was lower in ARDSnet-high compared with ARDSnet-low (0.0007).

CONCLUSION

Progression to ARDS, 24 hours after PC, was mitigated by OLC and ARDSnet-high. Both concepts restored EELV. ARDSnet-high had the lowest mechanical power surrogate and DAD. Our data suggest, that ARDSnet-high restored oxygenation and functional lung volume and reduced physiological and histological surrogates for VILI. ARDSnet-low generated unfavorable outcomes, such as loss of EELV, increased mechanical power and DAD after PC in swine. The high respiratory rate in the OLC may blunt favorable effects of lung recruitment.

[Bilateral thoracic trauma-"double the trouble"?]

BACKGROUND

Thoracic trauma is associated with a high morbidity and mortality. Assessing the risk for complications is essential for planning the further treatment strategies and managing resources in thoracic trauma.

OBJECTIVE

The aim of the study was to analyze concomitant injuries in unilateral and bilateral rib fractures and pulmonary contusions and evaluate differences in complication rates between the two.

MATERIAL AND METHODS

In a retrospective study, data from all patients diagnosed with thoracic trauma at a level I trauma center were analyzed. Bivariate and multivariate analysis were used to examine an association of unilateral or bilateral rib fractures, serial rib fractures, and pulmonary contusions with multiple injuries and outcomes. In addition, multivariate regression analysis was utilized to determine the impact of age, gender and additional injuries on outcome.

RESULTS

A total of 714 patients were included in the analysis. The mean Injury Severity Score (ISS) was 19. Patients with an additional thoracic spine injury had a significantly higher incidence of bilateral rib fractures. Pulmonary contusions were associated with younger age. Abdominal injuries were predictors for bilateral pulmonary contusions. Complications occurred in 36% of the patients. Bilateral injuries increased the complication rate up to 70%. Pelvic and abdominal injuries as well as the need for a chest drain were significant risk factors for complications. The mortality rate was 10%, with higher age, head and pelvic injuries as predictors.

CONCLUSION

Patients with bilateral chest trauma had an increased incidence of complications and a higher mortality rate. Bilateral injuries and significant risk factors must therefore be considered. Injury of the thoracic spine should be excluded in those patients.

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.

[Pathophysiology, Diagnostics and Therapy of Pulmonary Contusion - Recommendations of the Interdisciplinary Group on Thoracic Trauma of the Section NIS of the German Society for Trauma Surgery (DGU) and the German Society for Thoracic Surgery (DGT)]

Pulmonary contusion usually occurs in combination with other injuries and is indicative of a high level of force. Especially in multiply injured patients, pulmonary contusions are frequently detected. The injury is characterised by dynamic development, which might result in difficulties in recognising the actual extent of the injury at an early stage. Subsequently, correct classification of the extent of injury and appropriate initiation of therapeutic steps are essential to achieve the best possible outcome. The main goal of all therapeutic measures is to preserve lung function as best as possible and to avoid associated complications such as the development of pneumonia or Acute Respiratory Distress Syndrome (ARDS).The present report from the interdisciplinary working group "Chest Trauma" of the German Society for Trauma Surgery (DGU) and the German Society for Thoracic Surgery (DGT) includes an extensive literature review on the background, diagnosis and treatment of pulmonary contusion. Without exception, papers with a low level of evidence were included due to the lack of studies with large cohorts of patients or randomised controlled studies. Thus, the recommendations given in the present article correspond to a consensus of the aforementioned interdisciplinary working group.Computed tomography (CT) of the chest is recommended for initial diagnosis; the extent of pulmonary contusion correlates with the incidence and severity of complications. A conventional chest X-ray may initially underestimate the injury, but is useful during short-term follow-up.Therapy for pulmonary contusion is multimodal and symptom-based. In particular, intensive care therapy with lung-protective ventilation and patient positioning are key factors of treatment. In addition to invasive ventilation, non-invasive ventilation should be considered if the patient's comorbidities and compliance allows this. Furthermore, depending on the extent of the lung injury and the general patient's condition, ECMO therapy may be considered as an ultima ratio. In particular, this should only be performed at specialised hospitals, which is why patient assignment or anticipation of early transfer of the patient should be anticipated at an early time during the course.

Chest Tube Placement in Mechanically Ventilated Trauma Patients: Differences between Computed Tomography-Based Indication and Clinical Decision

The rate of occult pneumothorax in intubated and mechanically ventilated trauma patients until initial computed tomography (CT) remains undetermined. The primary aims of this study were to analyze initial chest CTs with respect to the thoracic pathology of trauma, the clinical injury severity, and chest tube placement (CTP) before and after CT. In a single-center retrospective analysis of 616 intubated and mechanically ventilated adult patients admitted directly from the scene to the emergency department (ED), 224 underwent CTP (36%). Of these, 142 patients (62%) underwent CTP before CT, of which, 125 (88%) had significant chest injury on CT. Seventeen patients had minor or absent chest injuries, most of which were associated with transient or unrecognized tracheal tube malposition. After CT, CTP was performed in another 82 patients, of which, 56 (68.3%) had relevant pneumothorax and 26 had minor findings on CT. Sixty patients who had already undergone CTP before CT received another CTP after CT, of which, 15 (25%) had relevant pneumothorax and 45 (75%) had functionality issues or malposition requiring replacement. Nine patients showed small pneumothorax on CT, and did not undergo CTP (including four patients with CTP before CT). The physiological variables were unspecific, and the trauma scores were dependent on the CT findings for identifying patients at risk for CTP. In conclusion, the clinical decisions for CTP before CT are associated with relevant false-negative and false-positive cases. Clinical assessment and CT imaging, together, are important indicators for CTP decisions that cannot be achieved by using clinical assessment or CT alone.

Lung failure after polytrauma with concomitant thoracic trauma in the elderly: an analysis from the TraumaRegister DGU®

Background

In developed countries worldwide, the number of older patients is increasing. Pulmonary complications are common in multiple injured patients with chest injuries. We assessed whether geriatric patients develop lung failure following multiple trauma with concomitant thoracic trauma more often than younger patients.

Methods

A retrospective analysis of severely injured patients with concomitant blunt thoracic trauma registered in the TraumaRegister DGU® (TR-DGU) between 2009 and 2018 was performed. Patients were categorized into four age groups: 55–64 y, 65–74 y, 75–84 y, and ≥ 85 y. Adult patients aged 18–54 years served as a reference group. Lung failure was defined as PaO2/FIO2 ≤ 200 mm Hg, if mechanical ventilation was performed.

Results

A total of 43,289 patients were included, of whom 9238 (21.3%) developed lung failure during their clinical stay. The rate of posttraumatic lung failure was seen to increase with age. While lung failure markedly increased the length of hospital stay, duration of mechanical ventilation, and length of ICU stay independent of the patient’s age, differences between younger and older patients with lung failure in regard to these parameters were clinically comparable. In addition, the development of respiratory failure showed a distinct increase in mortality with higher age, from 16.9% (18–54 y) to 67.2% (≥ 85 y).

Conclusion

Development of lung failure in severely injured patients with thoracic trauma markedly increases hospital length of stay, length of ICU stay, and duration of mechanical ventilation in patients, regardless of age. The development of respiratory failure appears to be related to the severity of the chest trauma rather than to increasing patient age. However, the greatest effects of lung failure, particularly in terms of mortality, were observed in the oldest patients.

Trauma Team Activation: Which Surgical Capability Is Immediately Required in Polytrauma? A Retrospective, Monocentric Analysis of Emergency Procedures Performed on 751 Severely Injured Patients

There has been an ongoing discussion as to which interventions should be carried out by an “organ specialist” (for example, a thoracic or visceral surgeon) or by a trauma surgeon with appropriate general surgical training in polytrauma patients. However, there are only limited data about which exact emergency interventions are immediately carried out. This retrospective data analysis of one Level 1 trauma center includes adult polytrauma patients, as defined according to the Berlin definition. The primary outcome was the four most common emergency surgical interventions (ESI) performed during primary resuscitation. Out of 1116 patients, 751 (67.3%) patients (male gender, 530, 74.3%) met the inclusion criteria. The median age was 39 years (IQR: 25, 58) and the median injury severity score (ISS) was 38 (IQR: 29, 45). In total, 711 (94.7%) patients had at least one ESI. The four most common ESI were the insertion of a chest tube (48%), emergency laparotomy (26.3%), external fixation (23.5%), and the insertion of an intracranial pressure probe (ICP) (19.3%). The initial emergency treatment of polytrauma patients include a limited spectrum of potential life-saving interventions across distinct body regions. Polytrauma care would benefit from the 24/7 availability of a trauma team able to perform basic potentially life-saving surgical interventions, including chest tube insertion, emergency laparotomy, placing external fixators, and ICP insertion.

Risk factors and outcomes of unrecognised endobronchial intubation in major trauma patients

Background

Emergency tracheal intubation during major trauma resuscitation may be associated with unrecognised endobronchial intubation. The risk factors and outcomes associated with this issue have not previously been fully defined.

Methods

We retrospectively analysed adult patients admitted directly from the scene to the ED of a single level 1 trauma centre, who received either prehospital or ED tracheal intubation prior to initial whole-body CT from January 2008 to December 2019. Our objectives were to describe tube-to-carina distances (TCDs) via CT and to assess the risk factors and outcomes (mortality, length of intensive care unit stay and mechanical ventilation) of patients with endobronchial intubation (TCD <0 cm) using a multivariable model.

Results

We included 616 patients and discovered 26 (4.2%) cases of endobronchial intubation identified on CT. Factors associated with an increased risk of endobronchial intubations were short body height (OR per 1 cm increase 0.89; 95% CI 0.84 to 0.94; p≤0.001), a high body mass index (OR 1.14; 95% CI 1.04 to 1.25; p=0.005) and ED intubation (OR 3.62; 95% CI 1.39 to 8.90; p=0.006). Eight of 26 cases underwent tube thoracostomy, four of whom had no evidence of underlying chest injury on CT. There was no statistically significant difference in mortality or length of stay although the absolute number of endobronchial intubations was small.

Conclusions

Short body height and high body mass index were associated with endobronchial intubation. Before considering tube thoracostomy in intubated major trauma patients suspected of pneumothorax, the possibility of unrecognised endobronchial intubation should be considered.

[Management of thoracic trauma and intrathoracic injuries]

More than 45% of polytraumatized patients in Germany suffer from severe thoracic trauma. Due to the urgent time factor (e.g. respiratory insufficiency and severe bleeding), a structured procedure in the diagnostics and treatment according to the advanced trauma life support (ATLS) criteria is necessary both prehospital and in the emergency room in order to provide the patient with adequate care. If a patient is stable or can be stabilized there is the option of using extended diagnostics, such as whole body computer tomography (CT) scanning with contrast medium, to select a treatment that is optimally adapted to the injury pattern. This can be performed by open surgery, minimally invasive surgery and interventional radiologically/endoscopically and depends on the injured organ as well as the extent of the injury. This means that only an interdisciplinary approach guarantees optimal care for patients with thoracic trauma.