Pulmonary Evaluation of Earthquake Victims Followed Up in the Intensive Care Unit After the 2023 Turkey Kahramanmaras Earthquakes

INTRODUCTION AND STUDY OBJECTIVE

In Turkey, a total of 269 earthquakes took place from 1900 through 2023. The most devastating earthquakes in terms of casualties and extensive destruction occurred at 4:17am and 1:24pm local time on February 6, 2023 with the epicenters located in Pazarcik (Kahramanmaras) and Ekinozu (Kahramanmaras) and magnitudes of 7.7Mw and 7.6Mw, respectively. The aim of this study was to define the frequency of lung complications that occurred directly and/or developed during the intensive care follow-up of individuals affected by the Kahramanmaras earthquakes.

METHOD

A retrospective evaluation was conducted on the files of 69 patients who were rescued from the debris of collapsed buildings after the Kahramanmaras earthquakes and followed up in the intensive care unit in terms of the time under the debris, demographic data, vital signs, and lung complications that were present at the time of admission and developed during follow-up. SPSS for Windows v. 20.0 was used for data analysis.

RESULTS

The study included a total of 69 patients, of whom 29 (42%) were female and 40 (58%) were male. The mean age was 39.9 (SD = 16.9) years. The mean time under the debris was 53.9 (SD = 52) hours, and the mean time from rescue to the intensive care unit admission was 18.7 (SD = 12.8) hours. One or more pulmonary complications were detected in 52.2% (n = 36) of the patients at the time of admission. During the follow-up, 30.4% (n = 21) of the patients developed pulmonary congestion, 13.0% (n = 9) pneumonia, 1.5% (n = 1) alveolar hemorrhage, and 1.5% (n = 1) atelectasis, while no additional lung complications developed in the remaining 37 patients (53.6%).

CONCLUSION

Severe cases of individuals recovered from the debris can have a high prevalence of earthquake-related lung disorders and chest trauma, which may be associated with high mortality. The timely identification and effective intervention of pulmonary complications that may develop during follow-up can reduce mortality.

Study on chest injury and bulletproof vest protection under the combined action of blast wave and fragments

Using a simulation based method, this paper analysis the damage effect of blast wave and fragments on human body and the protective effect of bulletproof vest. The results show that compared with the single blast shock wave, the chest injury is more serious under the combined action of blast shock wave and fragments. The peak stress of sternum, costal cartilage and rib increases by 334.34%, 170.23% and 39.72%, respectively. The peak stress on the side of the lung decreases by 3.95%, with little change. The peak stress on the front and back of the lung increases by 83.58% and 409.09% respectively. Overall, the lung injury is aggravated. With the addition of the bulletproof vest, the damage caused by fragments is reduced, and the peak stress of the sternum and the costal cartilage decreases by 48.77% and 69.78%, respectively. Due to the interaction of the blast wave with the vest and the chest, the damage caused by blast wave is aggravated. The peak stress of rib increases by 13.55%, and the peak stress of lung front, side and back increases by 1.22%, 6.51% and 3.57%, respectively.

The effect of age on injury patterns in pedestrian deaths

Although it is known that elderly pedestrians are at increased risk of injury and death from vehicle crashes the specific pattern of lethal injuries related to age has not been extensively studied. Data on the numbers of pedestrian fatalities and ages were obtained from 1990 to 2020 from the Traffic Accident Reporting System, The University of Adelaide, Adelaide, South Australia and detailed autopsy data on fatal pedestrian crashes from the pathology database at Forensic Science SA, Adelaide, South Australia from 2000 to 2020. Fatal injuries were separated into the following regions: head/face, spine, chest, abdomen and limbs/skeleton. Analysis of 634 cases of pedestrian fatalities (1990-2020) showed a significant decline in numbers over the years (p < 0.001). Analysis of fatal injuries in 219 cases (2000-2020) showed a significant reduction in the proportion of fatal head injuries with increasing age (p < 0.05), a significant increase in the proportion of fatal chest injuries with increasing age (p < 0.01) and a significant increase in the proportion of fatal limb/skeletal injuries with increasing age (p < 0.05). Older pedestrians are, therefore, more likely to sustain lethal chest and limb/skeletal injuries than head injuries compared to those who are younger, presumably due to greater physical fragility that occurs with age, with loss of protective muscle bulk and bone density.

Blood Count-Derived Inflammatory Markers Correlate with Lengthier Hospital Stay and Are Predictors of Pneumothorax Risk in Thoracic Trauma Patients

(1) Background: Trauma is one of the leading causes of death worldwide, with the chest being the third most frequent body part injured after abdominal and head trauma. Identifying and predicting injuries related to the trauma mechanism is the initial step in managing significant thoracic trauma. The purpose of this study is to assess the predictive capabilities of blood count-derived inflammatory markers at admission. (2) Materials and Methods: The current study was designed as an observational, analytical, retrospective cohort study. It included all patients over the age of 18 diagnosed with thoracic trauma, confirmed with a CT scan, and admitted to the Clinical Emergency Hospital of Targu Mureş, Romania. (3) Results: The occurrence of posttraumatic pneumothorax is highly linked to age (p = 0.002), tobacco use (p = 0.01), and obesity (p = 0.01). Furthermore, high values of all hematological ratios, such as the NLR, MLR, PLR, SII, SIRI, and AISI, are directly associated with the occurrence of pneumothorax (p < 0.001). Furthermore, increased values of the NLR, SII, SIRI, and AISI at admission predict a lengthier hospitalization (p = 0.003). (4) Conclusions: Increased neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic inflammatory index (SII), aggregate inflammatory systemic index (AISI), and systemic inflammatory response index (SIRI) levels at admission highly predict the occurrence of pneumothorax, according to our data.

A Seat Belt Injury Causing a Large Breast Hematoma: A Case Report

Seat belts with shoulder restraints have decreased the frequency of life-threatening severe chest trauma caused by car accidents. However, the introduction of seat belt legislation has led to an increase in a specific pattern of blunt trauma known as seat belt syndrome, which includes rib, clavicle, spine, and sternum fractures, as well as rupture of hollow pelvic and abdominal viscera, mesenteric tears, and major vessel injuries. The shoulder restraint part of the three-point seat belt commonly rests near or over the female and male breast. A 54-year-old female presented to our emergency department complaining of swelling and pain in her left breast immediately after a traffic accident. The patient had used a seat belt with a shoulder restraint. Bruising was noted along her chest where there had been seat belt contact. Her breast hematoma was most likely caused by breast tissue compression between her rib and the seat belt. Contrast-enhanced computed tomography demonstrated a sizable breast hematoma with active arterial contrast material extravasation, as well as multiple left rib fractures. The patient was conservatively treated with analgesic and anti-inflammatory drugs. Complete resolution was achieved, and her breast returned to its normal appearance. Although endovascular treatment and surgical hemostasis have been proposed for the treatment of breast injuries with active bleeding, conservative treatment such as compression hemostasis may be feasible.

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.

Development and implementation of a time- and computationally-efficient methodology for reconstructing real-world crashes using finite element modeling to improve crash injury research investigations

Eleven Crash Injury Research and Engineering Network (CIREN) frontal crashes were reconstructed using a novel, time-efficient methodology involving a simplified vehicle model. Kinematic accuracy was assessed using novel kinematic scores between 0-1 and chest injury was assessed using literature-defined injury metric time histories. The average kinematic score across all simulations was 0.87, indicating good kinematic accuracy. Time histories for chest compression, rib strain, shoulder belt force, and steering column force discerned the most causative components of chest injury in all cases. Abbreviated Injury Scale (AIS) 2+ and AIS 3+ chest injury risk functions using belt force identified chest injury with 81.8% success.

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.

Blunt Chest Trauma in Polytraumatized Patients: Predictive Factors for Urgent Thoracotomy

Purpose: Current guidelines on urgent thoracotomy of polytraumatized patients are based on data from perforating chest injuries. We aimed to identify predictive factors for urgent thoracotomy after chest-tube placement for blunt chest trauma in a civilian setting. Methods: Polytraumatized patients (Injury Severity Score ≥16) with blunt chest trauma, submitted to a level I trauma centre during a period of 12 years that received at least one chest tube were included. Trauma mechanism, chest-tube output, haemoglobin values, need for cellular blood products, coagulopathies, rib fracture pattern, thoracotomy, and mortality were retrospectively analysed. Results: 235 polytraumatized patients were included. Patients that received urgent thoracotomy (UT, n = 10) showed a higher mean chest-tube output within 24 h with a median (Mdn) of 3865 (IQR 2423–5156) mL compared to the group with no additional thoracic surgery (NT, n = 225) with Mdn 185 (IQR 50–463) mL (p < 0.001). The cut-off 24-h chest-tube output value for recommended thoracotomy was 1270 mL (ROC-Curve). UT showed an initial haemoglobin of Mdn 11.7 (IQR 9.2–14.3) g/dL and an INR value of Mdn 1.27 (IQR 1.11–1.69) as opposed to Mdn 12.3 (IQR 10–13.9) g/dL and Mdn 1.13 (IQR 1.05–1.34) in NT (haemoglobin: p = 0.786; INR: p = 0.215). There was an average number of 7.1(±3.4) rib fractures in UT and 6.7(±4.8) in NT (p = 0.649). Conclusions: Chest-tube output remains the single most important predictive factor for urgent thoracotomy also after blunt chest trauma. Patients with a chest-tube output of more than 1300 mL within 24 h after trauma should be considered for transfer to a level I trauma centre with standby thoracic surgery.

Computed tomographic findings of chest injuries following cardiopulmonary resuscitation: More complications for prolonged chest compressions?

Chest injuries are common and inevitable complications of chest compressions during cardiopulmonary resuscitation (CPR). This study aimed to investigate lung parenchymal and thoracic skeletal injuries after CPR by using computed tomography (CT) and to analyze the correlation between the duration of CPR and related complications.We examined 43 non-traumatic cardiac arrest patients who were successfully resuscitated after CPR and had chest CT scans within 24 hours of CPR. Lung parenchymal injuries were assessed by quantifying the lung contusion score (LCS) on the CT images, and each skeletal injury was investigated by classifying the location and the distribution. Other CPR-related chest injuries were also described, such as pleural effusion/hemothorax, pneumothorax, and retrosternal hematoma. Statistical analysis was conducted to determine whether the duration of CPR was correlated with each complication.Lung contusions were found in all of the patients (mean LCS: 22, range: 5-47). The distribution of lung contusions were predominantly in the bilateral dependent portions of the lungs (41 patients). All of the rib fractures occurred in the anterior arc (43 patients), and the sternal fractures occurred predominantly in the mid-sternal body (31 patients). In patients younger than 70 years old, the number of rib fractures significantly increased among those who underwent CPR for more than 25 minutes compared to those who received CPR for less than 25 minutes (median 4.5 vs 9; mean 8.3 vs 5.6 per person, respectively; P = .035). The risk of sternal fracture tended to be higher for patients who received CPR for more than 10 minutes compared to those who received CPR for less than 10 minutes (odds ratio: 3.60; 95% confidence interval: 0.86-15.06; P = .079). However, there was no statistically significant correlation between the duration of CPR and LCS or other CPR-related chest injuries.The duration of CPR was associated with the number of rib fractures and the occurrence of sternal fractures, but it did not affect the extent of CPR-related lung contusions or other CPR-related chest injuries. All of the rib fractures occurred in the anterior arc, while the sternal fractures occurred predominantly in the mid-sternal body. However, since this study was conducted in a single institution, the number of patients included was relatively small, thus limiting the statistical analysis.

Profile of Chest Injuries and Oxygen Therapy in Trauma Patients with Acute Respiratory Failure after the Jiangsu Tornado in China: A Retrospective Study

BACKGROUND

The aim of this study was to analyze the profile of chest injuries, oxygen therapy for respiratory failure, and the outcomes of victims after the Jiangsu tornado, which occurred on June 23, 2016 in Yancheng City, Jiangsu Province, China.

METHODS

The clinical records of 144 patients referred to Yancheng City No.1 People's Hospital from June 23 through June 25 were retrospectively investigated. Of those patients, 68 (47.2%) sustained major chest injuries. The demographic details, trauma history, details of injuries and Abbreviated Injury Scores (AIS), therapy for respiratory failure, surgical procedures, length of intensive care unit (ICU) and hospital stay, and mortality were analyzed.

RESULTS

Of the 68 patients, 41 (60.3%) were female and 27 (39.7%) were male. The average age of the injured patients was 57.1 years. Forty-six patients (67.6%) suffered from polytrauma. The mean thoracic AIS of the victims was calculated as 2.85 (SD = 0.76). Rib fracture was the most common chest injury, noted in 56 patients (82.4%). Pulmonary contusion was the next most frequent injury, occurring in 12 patients (17.7%). Ten patients with severe chest trauma were admitted to ICU. The median ICU stay was 11.7 (SD = 8.5) days. Five patients required intubation and ventilation, one patient was treated with noninvasive positive pressure ventilation (NPPV), and four patients were treated with high-flow nasal cannula (HFNC). Three patients died during hospitalization. The hospital mortality was 4.41%.

CONCLUSIONS

Chest trauma was a common type of injury after tornado. The most frequent thoracic injuries were rib fractures and pulmonary contusion. Severe chest trauma is usually associated with a high incidence of respiratory support requirements and a long length of stay in the ICU. Early initiation of appropriate oxygen therapy was vital to restoring normal respiratory function and saving lives. Going forward, HFNC might be an effective and well-tolerated therapeutic addition to the management of acute respiratory failure in chest trauma.

Adapting load limiter deployment for frontal crash diversity

Objective: Current European restraint systems may not realize their full protection potential in real-world frontal crashes because they are highly optimized for specific conditions. This research sought to quantify the potential benefit of adapting seat belt load limit thresholds to a wider range of occupant and crash characteristics.Methods: Numerical simulations using Hybrid III dummies were conducted to determine how varying load limiter thresholds could affect occupant kinematics and injury outcome in frontal impacts. Occupant-compartment models were developed with a restraint system consisting of a frontal airbag and a 3-point belt with retractor, buckle pretensioner, and load limiting at the shoulder. Load limiting threshold was varied in 5 frontal impact scenarios, covering as wide a range of real frontal crash conditions as possible. The simulated thoracic injury risks were converted into injury probability values using Abbreviated Injury Scale (AIS) 2+ age-dependent thoracic risk curves. These values were then applied to a British real-world frontal impact sample to determine the injury reduction potential of optimized load limiting, taking into account occupant seating position, impact scenario, occupant size, and occupant age and assuming that an appropriate adaptive system was fitted to all cars.Results: In low-severity impacts, a low load limit provided the best chest protection, without increasing risk to other body regions, for both the 50th and 95th percentile dummies in both front seating positions. In high-severity impacts, the low limit was not recommended because it allowed the driver dummy to move into close proximity with the vehicle interior, although there appeared to be some benefit of lower load limiting for the 50th percentile front passenger dummy, due to the increased ride down space in that seating position. Adapting the load limit showed no injury reduction potential for 5th percentile drivers. Utilizing the best load limit threshold in real-world crashes could reduce the number of occupants with AIS 2+ chest injuries from belt loading from 377 to 251 (a 33% reduction), correspondingly reducing the number of occupants with AIS 2+ chest injuries (from all sources) in the whole frontal impact population from 496 to 370. This is a reduction in injury rate from 6.4% to 4.8%.Conclusions: The concept of an adaptive load limiter shows most promise in low-speed frontal crashes where it could lower the AIS 2+ chest injury risk for most front seat occupants, except the smallest of drivers. Generally, adaptive limiters show less potential effectiveness with increased crash severities. Overall, an intelligent adjustment of load limiting threshold could result in a reduction of at least a third of front seat occupants with AIS 2+ chest injuries associated with restraining loads and an overall reduction in AIS 2+ chest injury rate in frontal crashes from 6.4% to 4.8.

Factors associated with chest injuries to front seat occupants in frontal impacts

Objective: Frontal impact chest protection in European cars has been highlighted as an area where possible improvements could be made. The chest is particularly vulnerable in older occupants whose numbers are forecast to increase significantly in the coming decades. This study aimed to provide some direction to areas for possible improvements in frontal crash chest protection.Methods: Real-world crash injury data were interrogated, focusing on cars with current restraint components. The research examined belted front seat occupants in frontal impacts where airbags, pretensioners, and load limiters were present.Results: The chest was the most often injured body region at Abbreviated Injury Scale (AIS) 2+, 3+, and 4+ injury levels. The rate of AIS 2+ and AIS 3+ chest injuries was highest among elderly occupants and lowest among young occupants, and elderly occupants sustained proportionally more severe chest injuries in low/moderate-speed impacts compared to young and middle-aged occupants. However, it should be noted that rates of AIS 2 chest injury were also significantly higher for middle-aged occupants compared to the young. The front passenger seat was shown to be more often associated with significant chest injury than the driver seat. The higher proportion of elderly female occupants was postulated as a reason for this. Skeletal injury was the most frequent type of AIS 2+ chest injury, and the rate of injury for elderly occupants with such injuries was higher than that for young and middle-aged occupants. With the increase in the number of rib fractures, the risk of pulmonary complications and organ injuries tended to increase. The major cause of chest injury was identified as restraining loads transmitted to the chest via the seat belt. The absence of intrusion in the majority of cases suggests an opportunity for the restraint system to better manage the crash pulse, not only for elderly occupants but for those who are middle-aged as well.Conclusions: This study shows the necessity for safety interventions, through new vehicle crashworthiness systems, to improve chest protection, especially for middle-aged and elderly car occupants. Deployment of appropriate injury risk criteria, use of an appropriate dummy thorax, development of a low-energy restraint test, and the development of more adaptive restraints have been discussed as possible solutions to the problem.

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.

[Drainage data analysis of chest-injured patients]

INTRODUCTION

Chest injuries cause a significant number of pneumothorax (PTX) and hemothorax (HTX). The most commonly used treatment is chest-tube drainage. The position of the tube is a prime necessity to achieve adequate drainage.

AIM

To analyze the duration of chest drainage at the occurrence of PTX and HTX. To find what the underlying cause of drainage insufficiency is and whether there is any relation between the surgical qualification needed to the procedure.

METHOD

Clinical data of 110 injured patients from 2011 to 2015 were collected and retrospectively analyzed. In the case of tube breaking or drainage insufficiency it was investigated if repositioning, usage of new tubes or insertion of additional tubes resolved the drainage insufficiency. Authors investigated the location of the tube on x-ray and CT, and the connection between the drainage insufficiency and the surgical qualifications needed to the procedure.

RESULTS

The average duration of chest drainage was 6.5 days. The duration of drainage was shorter by 1.9 days regarding the tube inserted in the middle section of the chest compared to the upper one and shorter by 1.2 days regarding the tube inserted in the lower section of the chest compared to the upper one. In the case of HTX, the duration of drainage was shorter by 2.8 days regarding the lower and by 3.6 days regarding the middle section compared to the upper position. Drainage insufficiency occurred in 30% of all cases. The duration of chest drainage was shorter after application of new tubes (9.5 days) than after reposition (10.2 days), but there was no significant difference.

CONCLUSION

Chest injury is a wide entity, thus one standard protocol cannot be developed on the management of these injuries. Authors concluded that drainage duration decreases significantly if the position of the tube is in the middle or lower section of the chest. The high occurrence of drainage insufficiency was caused by inadequate tube positioning and tube breaking. The practical qualification of trauma surgeons did not play a significant role regarding the prevalence of drainage insufficiency rather if the tube positioning was appropriate. Orv Hetil. 2019; 160(5): 172-178.

Nonlinear models of injury risk and implications in intervention targeting for thoracic injury mitigation

OBJECTIVE

Field data analyses often use either parametric or nonparametric means to describe the relationship between risk and various predictor variables. This study sought to evaluate a hybrid approach using semiconstrained multivariate nonlinear spline-based analysis.

METHODS

Data were compiled from NASS-CDS years 1998-2015, selecting belted occupants age 16+ in collisions with a principal direction of force (PDOF) from 10 o'clock to 2 o'clock. Outcome measures included the incidence of Maximum Abbreviated Injury Scale (MAIS) 3+ injury in general and Abbreviated Injury Scale (AIS) 3+ rib fracture injury. Multivariate logistic regression models were fit controlling for PDOF, ΔV, vehicle model year, collision year, occupant age, occupant body mass index (BMI), and other select factors. Within the logistic regression models, each of the continuous variables was modeled with a 4-knot spline. These were compared to models treating ΔV and BMI linearly.

RESULTS

A total of 29,667 occupants were observed from the query, representing approximately 13,608,398 occupants when weighted. Sixty percent of the AIS 3+ rib fracture cases occurred at ΔVs at or below 40 km/h. The median age for cases without AIS 3+ rib fracture was 34 years old. The median age for cases with AIS 3+ rib fracture was 62 years old. When modeled via nonlinear spline, the risk of MAIS 3+ injury in general and AIS 3+ rib fracture injury specifically exhibited a relationship with ΔV similar in shape to that observed in the linear model. In both cases, the spline model exhibited greater risk prediction over ΔVs from 25 to 50 km/h compared to the linear model (20-33% greater risk at ΔVs below 40 km/h) and less risk than the linear model at greater ΔVs. BMI exhibited a nonlinear, nonmonotonic relationship with both injury types studied. The risk tended to be a minimum at BMIs of 22-24 kg/m², with an increase in risk at both higher and lower BMIs. For AIS 3+ rib fracture, the risk for a person with a BMI of 18 was approximately equal to the risk for a person with a BMI of 30, both being approximately 40% greater than the risk associated with a BMI of 24.

CONCLUSIONS

Nonlinear multivariate regression methods have the potential to convey information about the risk-predictor relationship that cannot be captured through traditional linear modeling. These results suggest that traditional linear logistic regression models may underestimate the risk of AIS 3+ rib fracture injury in the ΔV range where they most frequently occur (below 50 km/h). Due to its nonmonotonic effect, traditional linear models may underestimate injury risk at both high and low BMIs.

The Association between Cardiopulmonary Resuscitation in Out-of-Hospital Settings and Chest Injuries: A Retrospective Observational Study

OBJECTIVES

The aim of this study was to assess the risk of cardiopulmonary resuscitation (CPR) performed in out-of-hospital settings for chest injuries in patients with out-of-hospital cardiac arrest (OHCA).

METHODS

This retrospective, observational study was conducted in an emergency critical care medical center in Japan. Non-traumatic OHCA patients transferred to the hospital from April 2013 through August 2016 were analyzed. The outcome was defined by chest injuries related to CPR, which is composite of rib fractures, sternal fractures, and pneumothoraces. A multivariate logistic regression analysis was performed to assess the independent risk factors for chest injuries related to CPR. The threshold of out-of-hospital CPR duration that increased risk of chest injuries was also assessed.

RESULTS

A total of 472 patients were identified, of whom 233 patients sustained chest injuries. The multivariate logistic regression model showed that the independent risk factors for chest injuries were age and out-of-hospital CPR duration (age: AOR=1.06 [95% CI, 1.04 to 1.07]; out-of-hospital CPR duration: AOR=1.03 [95% CI, 1.01 to 1.05]). In-hospital CPR duration was not an independent risk factor for chest injuries. When the duration of out-of-hospital CPR extended over 15 minutes, the likelihood of chest injuries increased; however, this association was not statistically significant.

CONCLUSIONS

Long duration of out-of-hospital CPR was an independent risk factor for chest injuries, possibly due to the difficulty of maintaining adequate quality of CPR. Further investigations to assess the efficacy of alternative CPR devices are expected in cases requiring long transportation times. Takayama W , Koguchi H , Endo A , Otomo Y . The association between cardiopulmonary resuscitation in out-of-hospital settings and chest injuries: a retrospective observational study. Prehosp Disaster Med. 2018;33(2):171-175.

Interlocking Intramedullary Nailing Versus Locked Dual-Plating Fixation for Femoral Shaft Fractures in Patients with Multiple Injuries: A Retrospective Comparative Study

PURPOSE

Intramedullary nailing (IMN) is a popular method in the management of femoral shaft fractures (FSFs). However, whether the association of IMN with pulmonary fat emboli can compromise the pulmonary and nervous systems is debatable. The purpose of this study is to compare IMN with the locked dual plating (LDP) method by assessing the clinical outcomes of FSF patients with head or chest injury.

METHOD

A total of 126 FSF patients were included in this study between January 2010 and July 2016 and divided into LDP and IMN groups. Patient demographic characteristics, operative time, blood loss, Harris Hip Score, Lysholm Knee Score, radiological outcomes, and systemic complications were collected and compared between the two treatment groups. Patients were followed up for at least 12 months.

RESULTS

The LDP group performed better than IMN in terms of operative time, estimated blood loss amount, and malunion rate. Differences in function scores, fracture union rate, overall pulmonary complication rate, and in-hospital mortality between the two groups were not significant. Average radiographic union time was significantly longer in the LDP group (36.3 weeks) than in the IMN group (32.5 weeks). One case of fixation failure occurred postoperatively in the LDP group, whereas one case of fracture nonunion took place in the IMN group.

CONCLUSION

Our findings suggest that dual-plating fixation is a promising method for FSFs with multiple injuries. However, the retrospective nature of this study necessitates high-quality trials to be performed to assess the clinical efficiency of dual plating.

Implementation evaluation and refinement of an intervention to improve blunt chest injury management-A mixed-methods study

Aims and objectives

To investigate uptake of a Chest Injury Protocol (ChIP), examine factors influencing its implementation and identify interventions for promoting its use.

Background

Failure to treat blunt chest injuries in a timely manner with sufficient analgesia, physiotherapy and respiratory support, can lead to complications such as pneumonia and respiratory failure and/or death.

Design

This is a mixed‐methods implementation evaluation study.

Methods

Two methods were used: (i) identification and review of the characteristics of all patients eligible for the ChIP protocol, and (ii) survey of hospital staff opinions mapped to the Theoretical Domains Framework (TDF) to identify barriers and facilitators to implementation. The characteristics and treatment received between the groups were compared using the chi‐square test or Fischer's exact test for proportions, and the Mann–Whitney U‐test for continuous data. Quantitative survey data were analysed using descriptive statistics. Qualitative data were coded in NVivo 10 using a coding guide based on the TDF and Behaviour Change Wheel (BCW). Identification of interventions to change target behaviours was sourced from the Behaviour Change Technique Taxonomy Version 1 in consultation with stakeholders.

Results

Only 68.4% of eligible patients received ChIP. Fifteen facilitators and 10 barriers were identified to influence the implementation of ChIP in the clinical setting. These themes were mapped to 10 of the 14 TDF domains and corresponded with all nine intervention functions in the BCW. Seven of these intervention functions were selected to address the target behaviours and a multi‐faceted relaunch of the revised protocol developed. Following re‐launch, uptake increased to 91%.

Conclusions

This study demonstrated how the BCW may be used to revise and improve a clinical protocol in the ED context.

Relevance to clinical practice

Newly implemented clinical protocols should incorporate clinician behaviour change assessment, strategy and interventions. Enhancing the self‐efficacy of emergency nurses when performing assessments has the potential to improve patient outcomes and should be included in implementation strategy.

A Preventative Respiratory Protocol to Identify Trauma Subjects at Risk for Respiratory Compromise on a General In-Patient Ward

BACKGROUND

Patients are at risk for respiratory complications after sustaining blunt chest trauma, yet contradictory evidence exists about the utility of prophylactic respiratory therapy to reduce respiratory complications in this population. This study assessed the effectiveness of a proactive respiratory protocol on an in-patient ward to identify trauma patients at risk for pulmonary complications, administer appropriate therapies, and prevent deterioration requiring transfer to the ICU.

METHODS

Trauma patients received a respiratory therapy evaluation at the time of admission to a general in-patient ward at a Level 1 trauma center. If subjects met protocol inclusion criteria, they received prophylactic respiratory treatments, primarily MetaNeb therapy, Vest therapy, or EzPAP. Multiple phases were included to evaluate the effectiveness of the protocol, with 50 subjects in each phase: a pre-protocol phase before adoption of the protocol; phase 1, which was found to have low physician adherence and overly broad inclusion criteria; and phase 2, with improved adherence and narrower inclusion criteria. Study inclusion criteria mirror the protocol criteria from phase 2: ≥3 rib fractures; pulmonary contusion; exacerbation of COPD, asthma, or other lung disease; or age ≥65 y with expected immobility of ≥48 h.

RESULTS

The respiratory protocol was associated with an elimination of unplanned admissions to the ICU. After controlling for injury severity and other important clinical factors, receiving the protocol significantly decreased hospital stay by approximately 1.5 d. More subjects were admitted from the emergency department directly to the ward, avoiding the ICU. Bronchodilator use also decreased, although the result did not reach statistical significance.

CONCLUSIONS

Study results suggest that a preventive respiratory protocol had a beneficial effect on patient outcomes; receiving the protocol reduced hospital days and eliminated unplanned admission to the ICU.

Giant chronic expanding hematoma in the chest identified 25 years after a blunt chest trauma

We herein report the case of a 42-year-old man who presented with a huge intrathoracic mass that had grown over a period of 25 years. The initial symptom caused by the mass was dull pain in the chest. T2-weighted magnetic resonance imaging revealed a mosaic pattern of various signal intensities, indicating a chronic expanding hematoma. The mass was completely resected surgically. For patients who present with a slowly growing mass, particularly those with a history of tuberculous pleuritis, chest surgery or trauma, a chronic expanding hematoma should be taken into consideration. Surgical resection is the first choice of treatment for a chronic expanding hematoma caused by a blunt chest trauma.

Troponin T in Patients with Traumatic Chest Injuries with and without Cardiac Involvement: Insights from an Observational Study

BACKGROUND

Serum troponin T (TnT) is a common marker of myocardial injury. However, its implication in the absence of clinical evidence of cardiac reason is not well established.

AIMS

The aim of this study was to identify the implications of positive TnT in traumatic chest injury (TCI) patients regardless of the cardiac involvement.

MATERIALS AND METHODS

We conducted a retrospective analysis of all TCI patients admitted to level 1 trauma center between 2008 and 2011. Patients who underwent TnT testing were divided into two groups: Group 1 (positive TnT) and Group 2 (negative TnT). The two groups were analyzed and compared, and multivariate regression analyses were performed to identify predictors of TnT positivity and mortality.

RESULTS

Out of 993 blunt TCI patients, 19.3% had positive TnT (Group 1). On comparison to Group 2, patients in Group 1 were 5 years younger and more likely to have head, cardiac, hepatic, splenic, and pelvic injuries, in addition to lung contusion. Positive TnT was associated with higher Injury Severity Score (ISS) (P = 0.001), higher chest Abbreviated Injury Score (AIS) (P = 0.001), and longer hospital stay (P = 0.03). In addition, Group 1 patients were more likely to undergo chest tube insertion, exploratory laparotomy, mechanical ventilation, and tracheostomy. Twenty patients had cardiac involvement, and of them 14 had positive TnT. Among 973 patients who showed no evidence of cardiac involvement, 178 had positive TnT (18.3%). There were 104 deaths (60% in Group 1). On multivariate regression analysis, the predictors of hospital mortality were positive TnT, head injury, and high ISS, whereas, the predictors of TnT positivity were cardiac, hepatic, and pelvic injuries; higher ISS; and age.

CONCLUSIONS

Positive TnT in blunt TCI patients is a common challenge, particularly in polytrauma cases. Patients with positive TnT tend to have the worst outcome even in the absence of clinical evidence of acute cardiac involvement. Positive TnT is also a reflection of the severity of chest or extrathoracic injuries; however, further prospective studies are warranted.

Mitral Perivalvular Leak after Blunt Chest Trauma: A Rare Cause of Severe Subacute Mitral Regurgitation

Blunt chest trauma is a very rare cause of valve disorder. Moreover, mitral valve involvement is less frequent than is aortic or tricuspid valve involvement, and the clinical course is usually acute. In the present report, we describe the case of a 49-year-old man with a perivalvular mitral injury that became clinically manifest one year after a violent, nonpenetrating chest injury. This case is atypical in regard to the valve involved (isolated mitral damage), the injury type (perivalvular leak in the absence of subvalvular abnormalities), and the clinical course (interval of one year between trauma and symptoms).

Traumatic chest injury in children: A single thoracic surgeon's experience in two Nigerian tertiary hospitals

BACKGROUND

This study was to determine the extent and outcome of childhood chest injury in Nigeria, and to compare results with that of other literatures.

PATIENTS AND METHODS

A Prospective study of all children under 18 years of age with chest trauma in two tertiary hospitals in Southern Nigeria from January 2012 to December 2014 was reviewed. The aetiology, type, associated injury, mechanism, treatment and outcome were evaluated. The patients were followed up in the clinic. The data were analysed using SPSS version 20.0 with a significant P < 0.05.

RESULTS

Thirty-one patients (12.1%) under 18 years of age of 256 chest trauma patients were managed in the thoracic units. The mean age was 9.78 ± 6.77 years and 27 (87.1%) were male. The aetiology in 13 was from falls, 10 from automobile crashes, 3 from gunshots, 4 from stabbing and 1 from abuse. The highest peak of chest injury was on Saturday of the week and April of the year. The pleural collections are as follows: 15 (71.4%) was haemothorax, 4 (19.1%) pneumothorax, 2 (9.5%) haemopneumothorax and 18 patients had lung contusion in combination or alone with the pleural collections. Seven patients who presented >12-h versus 2 who presented <12-h and 6 of children between 0 and 9 years versus 3 at 10-18 years of age had empyema thoracis (P value not significant). One death was recorded.

CONCLUSION

Chest trauma in children is still not common, and blunt chest injury from falls and automobile accidents are more common than penetrating chest injury. Treatment with tube thoracostomy is the major management modality with empyema thoracis as the most common complication.

Improving the Chest Protection of Elderly Occupants in Frontal Crashes Using SMART Load Limiters

OBJECTIVE

To determine whether varying the seat belt load limiter (SBL) according to crash and occupant characteristics could have real-world injury reduction benefits in frontal impacts and, if so, to quantify those benefits.

METHODS

Real-world UK accident data were used to identify the target population of vehicle occupants and frontal crash scenarios where improved chest protection could be most beneficial. Generic baseline driver and front passenger numerical models using a 50th percentile dummy were developed with MADYMO software. Simulations were performed where the load limiter threshold was varied in selected frontal impact scenarios. For each SBL setting, restraint performance, dummy kinematics, and injury outcome were studied in 5 different frontal impact types. Thoracic injury predictions were converted into injury probability values using Abbreviated Injury Scale (AIS) 2+ age-dependent thoracic risk curves developed and validated based on a methodology proposed by Laituri et al. (2005). Real-world benefit was quantified using the predicted AIS 2+ risk and assuming that an appropriate adaptive system was fitted to all the cars in a real-world sample of recent frontal crashes involving European passenger cars.

RESULTS

From the accident data sample the chest was the most frequently injured body region at an AIS 2+ level in frontal impacts (7% of front seat occupants). The proportion of older vehicle front seat occupants (>64 years) with AIS 2+ injury was also greater than the proportion of younger occupants. Additionally, older occupants were more likely to sustain seat belt-induced serious chest injury in low- and moderate-speed frontal crashes. In both front seating positions, the low SBL provided the best chest injury protection, without increasing the risk to other body regions. In severe impacts, the low SBL allowed the driver to move dangerously close to the steering wheel. Compared to the driver side, greater ride-down space on the passenger side gave a higher potential for using the low SBLs. When applying the AIS 2+ risk reduction findings to the weighted accident data sample, the risk of sustaining an AIS 2+ seat belt injury changed to 0.9, 4.9, and 8.1% for young, mid, and older occupants, respectively, from their actual injury risk of 1.3, 7.6, and 13.1%.

CONCLUSIONS

These results suggest the potential for improving the safety of older occupants with the development of smarter restraint systems. This is an important finding because the number of older users is expected to increase rapidly over the next 20 years. The greatest benefits were seen at lower crash severities. This is also important because most real-world crashes occur at lower speeds.

Age-dependent factors affecting thoracic response: a finite element study focused on Japanese elderly occupants

OBJECTIVES

The ultimate goal of this research is to reduce thoracic injuries due to traffic crashes, especially in the elderly. The specific objective is to develop and validate a full-body finite element model under 2 distinct settings that account for factors relevant for thoracic fragility of elderly: one setting representative of an average size male and one representative of an average size Japanese elderly male.

METHODS

A new thorax finite element model was developed from medical images of a 71-year-old average Japanese male elderly size (161cm, 60 kg) postmortem human subject (PMHS). The model was validated at component and assembled levels against original series of published test data obtained from the same elderly specimen. The model was completed with extremities and head of a model previously developed. The rib cage and the thoracic flesh materials were assigned age-dependent properties and the model geometry was scaled up to simulate a 50th percentile male. Thereafter, the model was validated against existing biomechanical data for younger and elderly subjects, including hub-to-thorax impacts and frontal impact sled PMHS test data. Finally, a parametric study was conducted with the new models to understand the effect of size and aging factors on thoracic response and risk of rib fractures.

RESULTS

The model behaved in agreement with tabletop test experiments in intact, denuded, and eviscerated tissue conditions. In frontal impact sled conditions, the model showed good 3-dimensional head and spine kinematics, as well as rib cage multipoint deflections. When properties representative of an aging person were simulated, both the rib cage deformation and the predicted number of rib fractures increased. The effects of age factors such as rib cortical thickness, mechanical properties, and failure thresholds on the model responses were consistent with the literature. Aged and thereby softened flesh reduced load transfer between ribs; the coupling of the rib cage was reduced. Aged costal cartilage increased the severity of the diagonal belt loading sustained by the lower loaded rib cage.

CONCLUSIONS

When age-specific parameters were implemented in a finite element (FE) model of the thorax, the rib cage kinematics and thorax injury risk increased. When the effect of size was isolated, 2 factors, in addition to rib material properties, were found to be important: flesh and costal cartilage properties. These 2 were identified to affect rib cage deformation mechanisms and may potentially increase the risk of rib fractures.

Pretensioner loading to rear-seat occupants during static and dynamic testing

OBJECTIVE

Pretensioners reduce the seat belt slack and couple the occupant early to the restraint system. There is a growing prevalence of rear seat pretensioners and it is essential to determine whether the load from the pretensioner itself can cause injuries to rear-seated children. The aim of the study was to investigate the loading to the neck, chest, and abdomen of various sizes of anthropometric test devices (ATDs) during the pretensioner deployment phase and the crash phase in low-severity frontal sled tests and during static deployment.

METHODS

Low-severity frontal sled tests were conducted with the Hybrid III (HIII) 3-year-old, HIII 6-year-old, HIII 5th percentile, and HIII 50th percentile ATDs. Two different retractor pretensioners with varying pretensioner force were used. The child ATDs were restrained on a booster cushion (BC), with and without a back. The loading to the neck and chest was compared to injury assessment reference values (IARVs) reported by Mertz et al. (2003). The chest loading to the HIII 5th percentile and HIII 50th percentile ATDs was also analyzed using age-related injury risk curves. Static pretensioner tests with the Q-series 10-year-old ATD, equipped with an advanced abdominal loading device, were conducted in standard ATD position and out-of-position with the lap belt positioned high on the abdomen.

RESULTS

During the crash phase, head excursion and neck loading were reduced for both pretensioners for all ATDs compared to testing without a pretensioner. The pretensioner reduced chest deflection to the adult ATDs but not to child ATDs when seated on a BC with a back during the crash phase. When the back was removed, chest deflection was reduced below IARV. The head excursion was reduced for all ATDs with both pretensioners. During the pretensioner deployment phase, the chest deflection exceeded the IARV for the HIII 3-year-old with the stronger pretensioner when seated on booster with a back and it was reduced below the IARV with the lower force pretensioner. For all ATDs, neck and chest loading during the pretensioner deployment phase were reduced when a pretensioner with lower force was used. Abdominal loading to the Q10 in the static pretensioner deployments indicated a low risk of abdominal injury in all tested positions.

CONCLUSION

This study indicates the need to balance the pretensioner force and seat belt geometry to gain good pretensioner performance in both the pretensioner deployment phase and the crash phase.

Occlusion of the right coronary artery after blunt thoracic trauma with fatal outcome: A case report and review of the literature

BACKGROUND

Although damage of the heart vessels is a possible complication of blunt thoracic trauma, occlusion of the right coronary artery is rare and demands high level of suspicion by the emergency physicians.

OBJECTIVE

Our objective is to present a case of fatal acute occlusion of the right coronary artery after blunt thoracic trauma due to vehicle accident and conduct a brief review of the current literature.

CASE REPORT

A 58-year-old sustained chest trauma after a vehicle accident, complicated by acute occlusion of the right coronary artery. Despite invasive intervention the patient deteriorated and died due to multi-organ failure.

CONCLUSION

Acute occlusion of the right coronary artery is a rare complication of blunt chest trauma. Early diagnosis and intervention, collaboration between different specialties and proper hospitalization are vital for the outcome of the patient.

Thoracic injury metrics with side air bag: stationary and dynamic occupants

OBJECTIVE

Injury risk from side air bag deployment has been assessed using stationary out-of-position occupant test protocols. However, stationary conditions may not always represent real-world environments. Therefore, the objective of the present study was to evaluate the effects of torso side air bag deployment on close-proximity occupants, comparing a stationary test protocol with dynamic sled conditions.

METHODS

Chest compression and viscous metrics were quantified from sled tests utilizing postmortem human specimens (PMHS) and computational simulations with 3 boundary conditions: rigid wall, ideal air bag interaction, and close-proximity air bag deployment. PMHS metrics were quantified from chestband contour reconstructions. The parametric effect of DeltaV on close-proximity occupants was examined with the computational model.

RESULTS

PMHS injuries suggested that close-proximity occupants may sustain visceral trauma, which was not observed in occupants subjected to rigid wall or ideal air bag boundary conditions. Peak injury metrics were also elevated with close-proximity occupants relative to other boundary conditions. The computational model indicated decreasing influence of air bag on compression metrics with increasing DeltaV. Air bag influence on viscous metric was greatest with close-proximity occupants at DeltaV = 7.0 m/s, at which the response magnitude was greater than linear summation of metrics resulting from rigid impact and stationary close-proximity interaction.

CONCLUSIONS

These results suggest that stationary close-proximity occupants may not represent the only scenario of side air bag deployment harmful to the thoraco-abdominal region. The sensitivity of the viscous metric and implications for visceral trauma are also discussed.