Validated numerical unrestrained occupant-seat crash scenarios for high-speed trains integrating experimental, computational, and inverse methods.

OBJECTIVE: Occupant impact safety is critical for train development. This paper proposes a systematic procedure for developing validated numerical occupant crash scenarios for high-speed trains by integrating experimental, computational, and inverse methods. METHODS: As the train interior is the most potentially injury-causing factor, the material properties were acquired by mechanical tests, and constitutive models were calibrated using inverse methods. The validity of the seat material constitutive model was further verified via drop tower tests. Finite element (FE) and multibody (MB) models of train occupant-seat interactions in frontal impact were established in LS-DYNA and MADYMO software, respectively, using the experimentally acquired materials/mechanical characteristics. Three dummy sled crash tests with different folding table and backrest configurations were conducted to validate the numerical occupant-seat models and to further assess occupant injury in train collisions. The occupant impact responses between dummy tests and simulations were quantitatively compared using a correlation and analysis (CORA) objective rating method. RESULTS: Results indicated that the experimentally calibrated numerical seat-occupant models could effectively reproduce the occupant responses in bullet train collisions (CORA scores >80%). Compared with the train seat-occupant MB model, the FE model could simulate the head acceleration with slightly more acceptable fidelity, however, the FE model CORA scores were slightly less than for the MB models. The maximum head acceleration was 30 g but the maximum HIC score was 17.4. When opening the folding table, the occupant's chest injury was not obvious, but the neck-table contact and "chokehold" may potentially be severe and require further assessment. CONCLUSIONS: This study demonstrates the value of experimental data for occupant-seat model interactions in train collisions and provides practical help for train interior safety design and formulation of standards for rolling stock interior passive safety.

The sensitivity of a neck CT scan in detecting pneumothoraces in nonpenetrating trauma.

BACKGROUND: The trauma-related pneumothorax is a common intrathoracic injury and can go undetected with detrimental outcomes. Chest computed tomography (CT) investigation in low- to middle-income countries (LMIC) is not always readily available during emergency situations and increased workloads. However, alternative investigations all have limitations in including pneumothoraces. Patients may have trauma indications for CT of the head and neck. The neck CT scan may hold an extra potential advantage in pneumothorax detection. This study aimed to assess its sensitivity in pneumothorax detection in nonpenetrating trauma. METHODS: A retrospective study was conducted from 1 January 2016 to 31 December 2021. All adult patients sustaining nonpenetrating injuries, and investigated with chest and neck CT scans were included. The chest CT scan was the gold standard against,which the neck CT scan was compared to determine the accuracy of pneumothorax detection. Stata version 16 was used for descriptive statistical analysis, and a p-value of 0.05 was considered statistically significant. RESULTS: One thousand ninety three were eligible for evaluation; 204 (18.66%) pneumothoraces were detected on chest CT scans, 200 (98.0%) of which were also detected on the neck CT scan, producing a sensitivity of 98.0% (95% CI 95.1-99.5%) and a specificity of 100% (95% CI 99.6-100%). Most pneumothoraces were detected at T1 level (45.09%), followed by T2 (43.62%). CONCLUSION: The neck CT scan has demonstrated high sensitivity and specificity in pneumothorax detection. Thus, it may be used as an additional tool for those who could not receive or do not need a formal chest CT but have an indication for neck CT scans.

Biochemical markers in emergency thoracic surgery in penetrating trauma.

BACKGROUND: Violent interpersonal acts account for a large proportion of unnatural deaths in South Africa. A significant proportion of unnatural deaths are due to penetrating thoracic trauma and preventable haemorrhage. Current indications for emergent thoracotomy are unreliable. We propose the use of lactate, shock index (SI) and base deficit (BD) as a triage tool in patients with penetrating thoracic injuries to identify those requiring surgical intervention. METHODS: A review of the trauma registry of the Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) was carried out between March 2011 and March 2016. Four hundred and ninety (490) patients were collected consisting of a non-operative group of 246 patients and an operative group of 244 patients. We compared lactate, SI and BD independently and within panels to ascertain which would best predict the need for operative intervention in these patients. Abnormal was defined as lactate ≥ 4 mmol/l, SI ≥ 0.8 and BD ≤ -4 mmol/l. RESULTS: Of the 490 patients, lactate (p < 0.001), SI (p < 0.001) and BD (p < 0.001) differed significantly between operative and non-operative groups. Statistical significance was lost (p = 0.34) once BD was analysed in combination with lactate and SI. Lactate alone was a strong predictor of the need for intervention (area under the curve (AUC) = 0.814). The strongest predictor was a combined panel of lactate and SI (AUC = 0.8308, p < 0.001). CONCLUSION: Lactate and SI in combination are useful as triage tools, and could assist in decision making, by predicting which patients are more likely to require surgical intervention.

[A Review of 70 Cases of Thoracic Trauma with Rib Fixation:Indications and Practical Innovations of the Procedure].

We summarized the experience of surgical stabilization of rib fractures (SSRF) at a core hospital in eastern Hiroshima, which is a primary center for tertiary emergency medical care, especially for high-energy trauma cases including chest injuries. The study focuses on patients who underwent SSRF from January 2016 to September 2023, analyzing patient characteristics, injury mechanisms, associated injuries, fracture locations, time from injury to surgery, fixation devices used, and postoperative outcomes. Our hospital primarily treats elderly patients, and falls are the most common cause of injury, followed by traffic accidents. The criteria for SSRF in our hospital were clinical manifestations of flail chest, need for lung repair, persistent pain, or improvement of thoracic deformity. We had a high rate of fixation of fractures of the 4th-10th ribs, which have a significant impact on respiratory mechanics; although KANI plates were primarily used, the introduction of MatrixRIB plates offers advantages in certain scenarios. The study also identified challenges with the KANI plate, including cases of plate dislodgement, particularly in patients with multiple fractures and severe thoracic deformities. The combination of video-assisted thoracoscopic surgery and SSRF allows for more effective rib fixation and reduces surgical wound size and muscle damage.

[Video-assisted Thoracoscopic Surgery for Chest Trauma].

Video-assisted thoracoscopic surgery (VATS) is now commonly used in emergency surgery to confirm the site of injury and observe the thoracic cavity, especially in cases of chest trauma with stable vital signs. VATS was used in all 33 chest trauma surgeries performed at our department from October 2009 to July 2023. The common injury mechanisms were traffic trauma and falls, but there were also cases of trauma from a bullhorn, heavy machinery and farm equipment, and penetrating injury. The common surgical procedures were treatment of rib fractures and pulmonary suture or partial lung resection, followed by treatment of diaphragmatic injuries. Unusual surgical procedures included extrapleural hematoma drainage, pericardial drainage, hemostasis of intrathoracic bleeding from thoracic vertebral fracture, and lobectomy for airway bleeding. Here, we report our surgical policies and techniques for chest trauma. First, the thoracic cavity should be observed thoracoscopically to determine the site of injury. The key to repair is placement of a small thoracotomy directly above the rib fracture site, where dislocation is largest, followed by suture repair of the lung and diaphragm by combining direct and thoracoscopic views.

[Management of Tracheobronchial Injuries due to Brunt Trauma].

BACKGROUND: Tracheobronchial injuries resulting from blunt trauma are relatively rare among chest injuries. However, if these injuries are not managed properly, they can be fatal. The prognosis is intricately linked to the precise diagnosis and treatment. We herein report three cases of tracheobronchial trauma that required surgical intervention. Case 1:A 17-year-old male sustained injuries when his torso became entangled in heavy machinery. The diagnosis revealed a tear in the right main bronchus, which required transportation with left single- lung ventilation. The patient was treated by tracheobronchial reconstruction. Case 2:A 71-year-old male experienced trauma when his car collided with a utility pole. He was transported to the hospital after tracheal intubation due to a laceration of the tracheal membranous area. The site of the injury was closed with sutures. Case 3:A 17-year-old female who had been struck by a train suffered acute respiratory failure and was transported to the hospital after intubation. Veno-venous extracorporeal membrane oxgenation (VV-ECMO) was initiated in response to poor oxygenation. Complete rupture of the right middle bronchial trunk and laceration of the right main bronchial membrane were observed, and bronchoplasty was performed. CONCLUSION: A swift and accurate diagnosis, coupled with timely and judicious therapeutic interventions, play a pivotal role in managing tracheal and bronchial injuries.

[Outcomes of Surgical Treatment for Chest Trauma].

BACKGROUND: Intra-thoracic organ bleeding and chest wall injury following chest trauma can easily lead to life-threatening emergencies and a delay in treatment may lead to fatal outcomes. Interestingly, the optimal timing, indications, and surgical techniques have not been standardized. METHOD: We retrospectively analyzed 35 patients who underwent surgical treatment for chest trauma. RESULTS: All patients with penetrating trauma (n=4) underwent emergency surgery for a hemothorax. There were no postoperative complications or hospital deaths. All patients with blunt trauma( n= 31) had multiple rib fractures;rib fixation was performed in 29 patients( 94%). Eight patients( 26%) had flail chest. The duration from injury to surgery averaged 7.5 days. The prognosis was generally favorable with no postoperative complications, but two patients died in the hospital due to multiple organ failure caused by high-energy trauma. Patients with flail chest or multiple organ injury had prolonged postoperative hospital stays. CONCLUSIONS: Patients who sustain chest trauma follow various clinical courses. Appropriate timing of surgical intervention at an early stage after injury can be life saving and hasten a functional recovery.

[Traumatic damage to the diaphragm in children]. / Travmaticheskie povrezhdeniya diafragmy u detei.

OBJECTIVE: To analyze treatment outcomes in children with traumatic injuries of the diaphragm. MATERIAL AND METHODS: We followed-up 14 children aged 3-18 years with traumatic injuries of the diaphragm. Diagnostic measures included anamnesis, physical examination, pleural and abdominal puncture, bladder catheterization, ultrasound and X-ray examination including CT. RESULTS: Traumatic brain injury and thoracoabdominal trauma prevailed in children with traumatic injuries of the diaphragm. In 8 children, diaphragm injury was the result of a traffic accident. Of these, 5 ones died at the scene due to traumatic brain injury. In 3 children, diaphragm injury was associated with penetration of an iron pin through the perineum, pelvic cavity, abdominal and chest cavities when falling from a height (n=1) and sledding (n=2). Two children were littered with a pile of bricks and building materials. One girl suffered a diaphragm injury as a result of a stab wound. CONCLUSION: Combined damage to the diaphragm, TBI, chest and abdominal organs are serious injuries. Signs of shock, internal bleeding, respiratory failure and bone fractures come to the fore. Assistance to these children should be carried out in specialized hospitals.

Pancreatic injury due to blunt trauma on CT: does retropancreatic fat tissue reduce the severity of pancreatic injury?

BACKGROUND: Pancreatic injuries from blunt abdominal trauma have a high mortality rate, often accompanied by injuries to adjacent organs. This study aims to investigate the relationship between the size of retropancreatic adipose tissue and the severity of pancreatic and adjacent organ injuries in patients with pancreatic trauma. METHODS: We retrospectively screened computed tomography (CT) images of 34 patients (25 males, nine females, aged 13-69 years) and 34 controls (28 males, six females, aged 15-66 years) who suffered blunt abdominal trauma. The area of adipose tissue located posterior to the pancreatic body was measured in the axial plane for all subjects. The severity of pancreatic injury was assessed in terms of the injury site, the retropancreatic adipose tissue area, and the degree of other organ injuries. RESULTS: Pancreatic injuries were located in the head for 16 patients (23.5%), in the body for four patients (5.9%), and in the tail for 14 patients (20.6%). The retropancreatic fat area was found to be significantly smaller in patients with pancreatic trauma compared to controls (p<0.0001). Furthermore, the ratio of the retropancreatic fat area to the vertebral corpus area differed significantly between patients with and without pancreatic injuries (p=0.014). CONCLUSION: Retropancreatic adipose tissue protects the pancreatic body from the impacts of blunt abdominal trauma. An increased amount of retropancreatic adipose tissue is associated with a reduced rate of pancreatic injury.

Scapula fractures: functional anatomy, clinical assessment and management.

Fractures of the scapula are rare injuries, accounting for 3-5% of all shoulder girdle fractures. They are frequently the result of high energy trauma and often present with concurrent and life-threatening injuries to adjacent structures, leading to significant morbidity and mortality. Patients presenting with scapula fractures must receive a thorough and systematic clinical assessment as directed by national trauma guidelines. Appropriate imaging is essential in delineating fracture morphology and should at the very least include anteroposterior, anteroposterior oblique (Grashey) and axillary or scapula 'Y' view of the shoulder. Computed tomography imaging with three-dimensional reconstruction allows better delineation of the fracture morphology and helps with surgical planning. A lack of randomised controlled trials comparing the efficacy of conservative and operative management of scapula fractures has resulted in limited consensus for surgical indications. Nevertheless, most extra-articular fractures can be managed conservatively while intra-articular fractures of the glenoid frequently require surgical fixation.

Delayed flail chest from osteomyelitis and malnutrition that emerged 3 weeks after blunt chest trauma: a case report.

We present the case of a victim of a motor vehicle accident in his late 60s who suffered from severe torso injuries. He initially presented with abdominal and chest pain, and underwent emergency laparotomy for hemoperitoneum. After surgery, the patient developed pneumonia and septicemia, which were responsive to antibiotics. The patient was treated with mechanical ventilation in the intensive care unit for approximately 10 days and experienced a severe weight loss of approximately 30%, but slowly recovered without dyspnea. Notably, on hospital day 24, he experienced sudden respiratory distress and flail motion of the chest wall in a general ward. This late presentation of flail chest was attributed to non-union at rib fracture sites, and was likely exacerbated by malnutrition and osteomyelitis. Surgical stabilization of rib fractures and excision of the infected rib were successfully performed. The findings from this case highlight the complexity of managing delayed onset of flail chest. The findings from this case suggest the importance of vigilance for late emerging complications in patients with trauma, even when initial symptoms are absent.

Complex aortic-arch pseudoaneurysm with aorto-innominate vein fistula in a case of traumatic chest injury.

A patient in his late 30s presented with issues of retrosternal chest pain and palpitations. He had sustained a splinter injury to the left hemithorax a year ago for which he had been managed with a tube thoracostomy. During subsequent evaluations, he was found to have atrial fibrillations and a CT angiography revealed an arch of the aorta pseudoaneurysm with a fistulous communication with the innominate vein, which being a rare condition has no established treatment protocols. Endovascular salvage of the condition required an aortic Ishimaru zone 2 deployment of the thoracic endovascular aortic repair stent graft to provide an adequate landing zone. The elective left subclavian artery revascularisation was obtained by a left carotid artery to left subclavian artery bypass. Post procedure there was complete exclusion of the pseudoaneurysm sac, and the fistulous aorto-venous communication inflow tract. The patient recuperated well and has returned to full active duties.

Rib and sternum fracture risks for restrained occupants in frontal car crashes.

OBJECTIVE: Most car occupant fatalities occur in frontal crashes and the thorax is the most frequently injured body region. The objectives of the study were, firstly, to quantify the relation between risk factors (such as speed and occupant age) and rib and sternum fracture injury probability in frontal car crashes, and, secondly, to evaluate whether rib fracture occurrence can predict sternum fractures. METHODS: Weighted German data from 1999-2021 were used to create the injury risk curves to predict both, at least moderate and at least serious, rib and sternum fracture risks. A contingency table for rib and sternum fractures allowed the calculation of sensitivity, specificity, and precision, as well as testing for the association. RESULTS: Elderly occupants (≥65 years old) had increased rib and sternum fracture risk compared to mid aged occupants (18-64 years old). Besides occupant age, delta-V was always and sex sometimes a significant predictor for skeletal thoracic injury. Sternum fractures were more common than rib fractures and more likely to occur at any given delta-V. Sternum fractures occurred often in isolation. Female occupants were at higher risk than males to sustain at least moderate rib and sternum fractures together and sternum fractures in isolation. Rib and sternum fractures were associated, but low sensitivity and precision show that rib fractures do not predict sternum fractures well. CONCLUSIONS: Elderly and female occupants were at the highest risk and should be targeted by thoracic injury criteria and thresholds for frontal crash occupant protection. Rib and sternum fractures were not associated. Therefore, sternum fractures need to be predicted and evaluated separately from rib fractures.

Pulmonary fat embolism in non-survivors after cardiopulmonary resuscitation.

BACKGROUND: Blunt trauma acting against the human body presents the fundamental cause of pulmonary fat embolism (PFE) and fat embolism syndrome. The aim of the present study was to investigate PFE in non-survivors after cardiopulmonary resuscitation (CPR). METHODS: This was a prospective cohort study conducted in University Hospital Ostrava, Czech Republic. Within a 4-year study period, all non-survivors after CPR because of out-of-hospital cardiac arrest were assessed for the study eligibility. The presence/seriousness of PFE was determined by microscopic examination of cryo-sections of lung tissue (staining with Oil Red O). RESULTS: In total, 106 persons after unsuccessful CPR were enrolled in the study. The most frequent cause of death in the study population (63.2% of cases) was cardiac disease (ischemic heart disease); PFE was not determined as the cause of death in any of our study cases. Sternal fractures were identified 66.9%, rib fractures (usually multiple) in 80.2% of study cases; the median number of rib fractures was 10.2 fractures per person. Serious intra-thoracic injuries were found in 34.9% of cases. Microscopic examination of lung cryo-sections revealed PFE in 40 (37.7%) study cases; PFE was most frequently evaluated as grade I or II. Occurrence of sternal and rib fractures was significantly higher in persons with PFE than between persons without PFE (p = 0.033 and p = <0.001). Number of rib fractures was also significantly higher in persons with PFE. The occurrence of serious intra-thoracic injuries was comparable in both our study groups (p = 0.089). CONCLUSIONS: PFE presents a common resuscitation injury which can be found in more than 30% of persons after CPR. Persons with resuscitation skeletal chest fractures have significantly higher risk of PFE development. During autopsy of persons after unsuccessful CPR, it is necessary to distinguish CPR-associated injuries including PFE from injuries that arise from other mechanisms.

Surgical treatment for a child with traumatic ventricular septal rupture and ventricular aneurysm.

A five-year-old boy was diagnosed with the ventricular septal rupture and ventricular aneurysm after blunt chest trauma in child abuse. Because of the intractable heart failure, he underwent operation in subacute period. Postoperative course was uneventful. The blunt cardiac injury in children can be caused by mild trauma and can be lethal. Surgical intervention should be considered when the clinical condition is unstable.

Very long-term effects of conservatively treated blunt thoracic trauma: A retrospective analysis.

INTRODUCTION: Despite the high incidence of blunt thoracic trauma and frequently performed conservative treatment, studies on very long-term consequences for these patients remain sparse in current literature. In this study, we identify prevalence of long-term morbidity such as chronic chest pain, shortness of breath, and analyze the effect on overall quality of life and health-related quality of life. METHODS: Questionnaires were send to patients admitted for blunt thoracic trauma at our institution and who were conservatively treated between 1997 and 2019. We evaluated the presences of currently existing chest pain, persistence of shortness of breath after their trauma, the perceived overall quality of life, and health-related quality of life. Furthermore, we analyzed the effect of pain and shortness of breath on overall quality of life and health-related quality of life. RESULTS: The study population consisted of 185 trauma patients with blunt thoracic trauma who were admitted between 1997 and 2019, with a median long term follow up of 11 years. 60 percent still experienced chronic pain all these years after trauma, with 40,7 percent reporting mild pain, 12,1 percent reporting moderate pain, and with 7,7 percent showing severe pain. 18 percent still experienced shortness of breath during exercise. Both pain and shortness of breath showed no improvement in this period. Pain and shortness of breath due to thoracic trauma were associated with a lower overall quality of life and health-related quality of life. CONCLUSION: Chronic pain and shortness of breath may be relatively common long after blunt thoracic trauma, and are of influence on quality of life and health-related quality of life in patients with conservatively treated blunt thoracic trauma.

A meta-analysis and trial sequential analysis of randomised controlled trials comparing nonoperative and operative management of chest trauma with multiple rib fractures.

BACKGROUND: Operative treatment of traumatic rib fractures for better outcomes remains under debate. Surgical stabilization of rib fractures has dramatically increased in the last decade. This study aimed to perform a systematic review and meta-analysis of randomised controlled trials (RCTs) to assess the effectiveness and safety of operative treatment compared to conservative treatment in adult patients with traumatic multiple rib fractures. METHODS: A systematic literature review was performed according to the preferred reporting items for systematic reviews and meta-analyses guidelines. We searched MEDLINE, Scopus, and Cochrane Central Register of Controlled Trials and used the Cochrane Risk-of-Bias 2 tool to evaluate methodological quality. Relative risks with 95% confidence interval (CI) were calculated for outcomes: all-cause mortality, pneumonia incidence, and number of mechanical ventilation days. Overall certainty of evidence was evaluated with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, with trial sequential analysis performed to establish implications for further research. RESULTS: From 719 records, we included nine RCTs, which recruited 862 patients. Patients were assigned to the operative group (received surgical stabilization of chest wall injury, n = 423) or control group (n = 439). All-cause mortality was not significantly different (RR = 0.53; 95% CI 0.21 to 1.38, P = 0.35, I2 = 11%) between the two groups. However, in the operative group, duration of mechanical ventilation (mean difference -4.62; 95% CI -7.64 to -1.60, P < 0.00001, I2 = 94%) and length of intensive care unit stay (mean difference -3.05; 95% CI -5.87 to -0.22; P < 0.00001, I2 = 96%) were significantly shorter, and pneumonia incidence (RR = 0.57; 95% CI 0.35 to 0.92; P = 0.02, I2 = 57%) was significantly lower. Trial sequential analysis for mortality indicated insufficient sample size for a definitive judgment. GRADE showed this meta-analysis to have very low to low confidence. CONCLUSION: Meta-analysis of large-scale trials showed that surgical stabilization of multiple rib fractures shortened the duration of mechanical ventilation and reduced the incidence of pneumonia but lacked clear evidence for improvement of mortality compared to conservative treatment. Trial sequential analysis suggested the need for more cases, and GRADE highlighted low certainty, emphasizing the necessity for further targeted RCTs, especially in mechanically ventilated patients. SYSTEMATIC REVIEW REGISTRATION: UMIN Clinical Trials Registry UMIN000049365.