Quantitation and pattern of parenchymal lung injury in blunt chest trauma. Diagnostic and therapeutic implications

Characteristics of pediatric thoracic trauma: in view of before and after the establishment of a regional trauma center

Purpose

Pediatric thoracic trauma differs from those of adult in terms of the small anatomy and rapid tissue recovery. Therefore, it is important to know the characteristics of the pediatric thoracic trauma to improve treatment results. In addition, this study examined the changes in pediatric thoracic trauma features and results from the establishment of a level 1 regional trauma center.

Methods

Data of 168 patients’ ≤ 15 years old diagnosed with thoracic trauma between 2008 and 2019 were retrospectively analyzed.

Results

Pedestrian traffic accidents were the most common cause of chest injury. The average injury severity score was 17.1 ± 12.4 and the average pediatric trauma score was 5.6 ± 4.1. Lung contusion was the most common in 134 cases. There were 48 cases of closed thoracostomy. There was one thoracotomy for cardiac laceration, one case for extracorporeal membranous oxygenation, and six cases for embolization. Of all, 25 patients died, providing a mortality rate of 14.9%. In addition, independent risk factors of in-hospital mortality were hemopneumothorax and cardiac contusion. Since 2014, when the level 1 regional trauma center was established, more severely injured thoracic trauma patients came. However, the mortality was similar in the two periods.

Conclusions

Understanding the clinical features of pediatric thoracic trauma patients can help in efficient treatment. In addition, as the severity of pediatric thoracic trauma patients has increased due to the establishment of the regional trauma center, so pediatric trauma center should be organized in regional trauma center to improve the outcomes of pediatric thoracic trauma.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00068-021-01658-4.

Factors Predicting Lung Contusions in Critically Ill Trauma Children: A Multivariate Analysis of 330 Cases

PURPOSE

The aim of the study was to identify factors predicting lung contusion in trauma children.

METHODS

Retrospective study conducted for a period of 8 years (January 01, 2005-December 31, 2012) in a medical surgical intensive care unit. All trauma patients younger than 15 years were included. Two groups were compared: those with lung contusions (C+ group) and those without lung contusions (C- group).

RESULTS

We included 330 patients. The mean (SD) age was 7.6 (4.3) years. Chest injury was diagnosed in 70 patients (21.2%). All our patients needed mechanical ventilation. Lung contusions were diagnosed in 43 patients (13% of all patients and 61.4% of patients with chest trauma). In multivariate analysis, independent factors predicting lung contusion were road traffic accident (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.2-8.6; P = 0.019), increased Pediatric Risk of Mortality (PRISM) score (OR, 1.1; 95% CI, 1.1-1.2; P = 0.017), hepatic contusion (OR, 4.8; 95% CI, 1.3-17.1; P = 0.017), and pelvic ring fracture (OR, 3.5; 95% CI, 1.1-10.5; P = 0.026). Death occurred in 46 patients (13.9%). Intensive care unit mortality was significantly higher in the C+ group (OR, 2.5; 95% CI, 1.2-5.4; P = 0.021). However, mortality was not different between the 2 groups after adjusting for PRISM score (OR, 1.2; 95% CI, 0.5-2.9; P = 0.752) or after adjusting for Injury Severity Score (OR, 0.7; 95% CI, 0.3-2.1; P = 0.565).

CONCLUSIONS

Lung contusion is common in critically ill children with chest trauma. The diagnosis should be considered in patients with road traffic accident, increased PRISM score, hepatic contusion, and pelvic ring fracture.

Thoracoabdominal Injuries

Trauma to the thorax and abdomen can occur during participation in sports. This chapter reviews some of the more common presentations of such injuries and how such injuries should be best managed. Thoracic injuries reviewed include internal injuries such as pneumothorax, pulmonary contusion, hemothorax, commotio cordis, and cardiac contusion. Chest wall injuries are also reviewed such as rib fractures, costochondritis, and slipping rib syndrome plus sternal and scapular fractures. Abdominal injuries reviewed are focused on internal organ trauma to the spleen and liver, kidney, pancreas, and bowel. There is attention to the effect of Epstein-Barr virus and infectious mononucleosis, seen very frequently in high school and collegiate athletes. Finally, groin pain and athletic pubalgia are described.

In addition to anatomy and clinical presentation, imaging modalities that characterize such trauma are reviewed for each diagnosis. Prevention of thoracoabdominal injuries and return-to-play decisions are described at the chapter conclusion.

Effects of changing strategies of fracture fixation on immunologic changes and systemic complications after multiple trauma: damage control orthopedic surgery

In the treatment of polytrauma patients, multiple studies have shown how the timing and the type of the initial surgery of long bone fractures influence the incidence of systemic complications. Database analyses documented that unduly long surgical procedures undertaken early after trauma increase the risk of acute respiratory distress syndrome (ARDS), especially when femoral shaft fractures are stabilized. Animal research and prospective clinical studies also support the fact that the type of stabilization of a femoral shaft fracture may influence the systemic response to trauma. Reamed intramedullary reaming and nailing for a femoral shaft fracture is associated with an increased risk of pulmonary fat embolization from the medullary canal. This can result in pulmonary compromise if certain cofactors are also present. Modified reamers have been developed to reduce this side effect. The mediating effects are immunologic changes, varying according to the magnitude of the surgical procedure. Pro-inflammatory markers (e.g., Interleukins) may be used to assess the inflammatory response to injury as well as the magnitude of surgery and the systemic impact induced by surgery. Serum levels of such markers can be used clinically to tailor the amount of surgery that is performed to the clinical condition of the patient. The potentially negative impact of excessive surgery in high-risk patients can be avoided by using a new grading system for the assessment of the clinical status of the injured patient. Most recently, a large prospective randomized multicenter study has documented that this grading system is effective for identifying these borderline patients, and that in the borderline patient a staged surgical approach, such as temporary femoral stabilization with an external fixator, reduces the incidence of systemic complications. This work has changed the surgical management of multiply injured patients toward an approach that is tailored to the clinical condition of the patient, as indicated by well-defined clinical parameters as well as objective measurements of serum cytokine levels.

Using 99mTc-DTPA radioaerosol inhalation lung scan as compared with computed tomography to detect lung injury in blunt chest trauma

BACKGROUND

Detection of pulmonary contusion in patients with blunt chest trauma is very important so as to commence therapy immediately to avoid irreversible damage. The purpose of our study was to evaluate the efficacy of technetium-99m diethylene triamine pentaacetic acid (99mTc-DTPA) aerosol inhalation lung scintigraphy in comparison with chest computed tomography (CT) in the diagnosis of pulmonary contusion at acute blunt chest trauma.

METHODS

Twenty-nine patients with isolated blunt chest trauma were referred to the emergency department of our hospital, and nine healthy people participated in this study. Sixteen patients who had pulmonary contusion on CT scans were referred to as group 1, and 13 patients who had normal CT scans as group 2. Nine healthy people comprised a control group. 99mTc-DTPA aerosol inhalation lung scintigraphy was performed on the first day in all patients.

RESULTS

The mean half time (T1/2) and penetration index values of 99mTc-DTPA clearance were significantly lower in groups 1 and 2 compared with the control group. Among the three groups, there were no significant differences in arterial blood gas analysis except for PO2. The mean T1/2 value of 99mTc-DTPA clearance did correlate with PO2 values but not with pH, PCO2, or HCO3 values.

CONCLUSIONS

99mTc-DTPA radioaerosol inhalation lung imaging may serve as a useful adjunct and supportive method to chest CT scanning for detecting mild pulmonary contusion.

Imaging of Acute Thoracic Injury: The Advent of MDCT Screening

Chest radiography remains the primary screening study for the assessment of victims of chest trauma, but computed tomography (CT), particularly multidetector CT (MDCT), has progressively changed the imaging approach to these patients. MDCT acquires thinner sections with greater speed, allowing higher quality axial images and nonaxial reformations than conventional or single-detector helical CT. The speed of MDCT, both in acquiring data and in reconstructing images, makes the performance of total body surveys in the blunt polytrauma patient practicable. In general, CT has been well documented to offer major advantages over chest radiography in both screening for thoracic injuries and in characterizing such injuries. This capacity has been enhanced by the application of multichannel data acquisition. The greater sensitivity of MDCT has been well demonstrated in diagnosing vascular and diaphragmatic injuries. This article reviews current concepts of diagnostic imaging in acute chest trauma from blunt force and penetrating mechanisms emphasizing the spectrum of diagnostic imaging findings for various injuries, based primarily on radiographic and CT appearances. The advantages of MDCT for selected injuries are emphasized.

Imaging Evaluation of Pediatric Chest Trauma

Following a discussion of the various imaging manifestations of pediatric chest trauma by anatomic location, the authors discuss their diagnostic approach to the pediatric multitrauma patient with an emphasis on chest imaging.

Blunt thoracic trauma: flail chest, pulmonary contusion, and blast injury

Blunt thoracic trauma can result in significant morbidity in injured patients. Both chest wall and the intrathoracic visceral injuries can lead to life-threatening complications if not anticipated and treated. Pain control, aggressive pulmonary toilet, and mechanical ventilation when necessary are the mainstays of supportive treatment. The elderly with blunt chest trauma are especially at risk for pulmonary deterioration in the several days postinjury and should be monitored carefully regardless of their initial presentation. Blunt thoracic trauma is also a marker for associated injuries, including severe head and abdominal injuries.

[Lung contusion: relevance of initial injured pulmonary volume measurement by computed tomography]

OBJECTIVE

To evaluate computed tomography quantification of injured pulmonary volume after thoracic trauma and its relevance for severity grade of patients with lung contusion.

STUDY DESIGN

Retrospective study in a major French Level I university trauma center.

PATIENTS AND METHODS

Clinical and biological data including oxygenation index (PaO2/FIO2) and therapeutics modalities during the first 5 days: positive end expiratory pressure (Peep) and nitric oxide (NO), were collected on 49 patients with lung contusion resulting from thoracic trauma. Injured pulmonary volume was evaluated on initial thoracic tomodensitometry by 2 senior radiologists. The correlation between oxygenation index, therapeutics modalities and initial injured pulmonary volume was assessed for signification.

RESULTS

Injured pulmonary volume larger than 37.75% of total lung volume is associated with both hypoxemia at the twenty-fourth hour (PaO2/FIO2 <300), and need for Peep >6 cm H2O and /or ongoing NO administration on day 5.

CONCLUSION

Injured parenchymal pulmonary volume evaluation on initial tomodensitometry seems to be an important indicator of lung contusion severity. Thoracic computed tomography provides additional prognostic information in the initial evaluation of thoracic trauma with parenchymal injury.

Should helical CT scanning of the thoracic cavity replace the conventional chest x-ray as a primary assessment tool in pediatric trauma? An efficacy and cost analysis

BACKGROUND/PURPOSE

Findings from studies in the trauma literature suggest that thoracic computed tomography (TCT) scanning should replace conventional radiographs as an initial imaging modality. Limited data exist on the clinical utility and cost of TCT scans in pediatric trauma. Our current practice is to obtain TCT scans in those children at risk for thoracic injures. The purpose of this study is to examine what additional information TCT provides, how frequently it results in a change in clinical management, and a cost/benefit analysis.

METHODS

Children 18 years old and younger that had both a Chest x-ray (CXR) and TCT scan in their initial workup were included. Indications for TCT scan were (1) any sign of thoracic injury on CXR, (2) pathologic findings on physical examination of the chest, and (3) high impact force to chest wall. A child may have had one or more indications for a TCT scan.

RESULTS

Between 1996 and 2000, 45 of 1,638 trauma patients met study criteria. Indications for TCT included thoracic injury on CXR (n = 27), findings on physical examination (n = 8) and high-impact force (n = 33). In 18 of the 45 (40%), injuries were detected with TCT imaging but not on CXR. These included contusions (n = 12), hemothorax (n = 6), pneumothorax (n = 5), widened mediastinum (n = 4), rib fractures (n = 2), diaphragmatic rupture (n = 1), and aortic injury (n = 1). In 8 patients (17.7%) TCT imaging resulted in a change in clinical management. These included insertion of a chest tube (n = 5) aortography (n = 2) and operation (n = 1). Age, sex, injury severity score, mechanism, and indication for TCT could not predict differences between TCT and CXR (P >.05). In our institution, the cost of a TCT is $200, and the patient charge is $906 ($94 per CXR). Based on our study data 200 TCTs would need to be done for each clinically significant change, increasing patient ($180,000) and hospital ($39,600) costs.

CONCLUSIONS

Helical TCT is a highly sensitive imaging modality for the thoracic cavity; however, routine CXR still provides clinically valuable information for the initial trauma evaluation at minimal cost. TCT should be reserved for selected cases and not as a primary imaging tool.

Pediatric thoracic trauma

Although thoracic injuries occur less frequently in children than adults, they remain a source of substantial morbidity and mortality. Disparate problems such as rib fractures, lung injury, hemothorax, pneumothorax, mediastinal injuries, and others may present in isolation or in combination with one another. Knowledge of the manner in which pediatric anatomy, physiology, and injury patterns change with age may expedite the evaluation of the pediatric chest after trauma. Differences in pulmonary functional residual capacity, blood volume, chest wall and spinal soft-tissue mobility, and cardiac function may translate into problems or benefits of important consequence. For example, although more predisposed to hypoxemia, young children may remain well compensated hemodynamically, despite significant blood loss. Rare injuries in children, such as cardiac and great vessel trauma, may remain undiagnosed precisely because of their scarcity and protean symptoms.

Appraisal of early evaluation of blunt chest trauma: development of a standardized scoring system for initial clinical decision making

BACKGROUND

Current techniques for assessment of chest trauma rely on clinical diagnoses or scoring systems. However, there is no generally accepted standard for early judgement of the severity of these injuries, especially in regards to related complications. This drawback may have a significant impact on the management of skeletal injuries, which are frequently associated with chest trauma. However, no convincing conclusions can be determined until standardization of the degrees of chest trauma is achieved. We investigated the role of early clinical and radiologic assessment techniques on outcome in patients with blunt multiple trauma and thoracic injuries and developed a new scoring system for early evaluation of chest trauma.

METHODS

A retrospective investigation was performed on the basis of 4,571 blunt polytrauma (Injury Severity Score [ISS] > or = 18) patients admitted to our unit. Inclusion criteria were treatment of thoracic injury that required intensive care therapy, initial Glasgow Coma Scale score greater than 8 points, and no local or systemic infection. Patients with thoracic trauma and multiple associated injuries (ISS > or = 18) were included. In all patients, the association between various parameters of the thoracic injuries and subsequent mortality and morbidity was investigated.

RESULTS

A total of 1,495 patients fulfilled the inclusion criteria. Patients' medical records and chest radiographs were reevaluated between May 1, 1998, and June 1, 1999. The association between rib fractures and chest-related death was low (> three ribs unilateral, mortality 17.3%, odds ratio 1.01) unless bilateral involvement was present (> three ribs bilateral, mortality 40.9%, odds ratio 3.43). Injuries to the lung parenchyma, as determined by plain radiography, were associated with chest-related death, especially if the injuries were bilateral or associated with hemopneumothorax (lung contusion unilateral, mortality 25.2%, odds ratio 1.82; lung contusion bilateral + hemopneumothorax, mortality 53.3%, odds ratio 5.1). When plain anteroposterior chest radiographs were used, the diagnostic rate of rib fractures (< or = three ribs) increased slightly, from 77.1% to 97.3% during the first 24 hours of admission. In contrast, pulmonary contusions were often not diagnosed until 24 hours after admission (47.3% at admission, 92.4% at 24 h, p = 0.002). A new composite scoring system (thoracic trauma severity score) was developed that combines several variables: injuries to the chest wall, intrathoracic lesions, injuries involving the pleura, admission PaO2/FIO2 ratio, and patient age. The receiver operating characteristic curve demonstrated an adequate discrimination, as demonstrated by a value of 0.924 for the development set and 0.916 for the validation set. The score was also superior to the ISS (0.881) or the thorax Abbreviated Injury Score (0.693).

CONCLUSION

Radiographically determined injuries to the lung parenchyma have a closer association with adverse outcome than chest-wall injuries but are often not diagnosed until 24 hours after injury. Therefore, clinical decision making, such as about the choice of surgery for long bone fractures, may be flawed if this information is used alone. A new thoracic trauma severity score may serve as an additional tool to improve the accuracy of the prediction of thoracic trauma-related complications.

Evaluation of the utility of computed tomography in the initial assessment of the critical care patient with chest trauma

OBJECTIVE

To determine the utility of thoracic computed tomography (TCT) in the initial assessment of critically ill patients with chest injuries.

DESIGN

Prospective observational study of cohorts.

SETTING

Trauma intensive care unit (ICU) of a Spanish Level III hospital (US equivalent Level I).

PATIENTS

Three hundred seventy-five patients with chest injuries were studied, grouped into two cohorts according to whether they underwent admission TCT (exposed cohort, group I, n = 104) or not (unexposed cohort, group II, n = 271).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Demographic data, initial severity scores, and chest radiograph (CXR)-based diagnosis were collected in all patients as independent variables. In patients of group I, we also recorded the TCT-based diagnosis and any incidents, complications, or therapy changes resulting from the TCT. The need for and duration of mechanical ventilation, length of ICU stay, and ICU mortality were gathered in the whole sample as dependent variables. The admission data were similar in the two groups, except for a higher Injury Severity Score (ISS) and thoracic ISS in group I. TCT proved to be more sensitive than CXR in detecting pulmonary contusion, hemothorax, pneumothorax, and vertebral fractures and in identifying the faulty placement of chest drainage tubes. TCT findings induced therapy changes in approximately 30% of patients in group I. In the other dependent variables studied, there were no differences between the two groups. In the multivariate analysis, the TCT screening had no effects on the time on mechanical ventilation, length of ICU stay, or mortality.

CONCLUSIONS

TCT detects more chest injuries in trauma patients than does CXR and induces therapy changes in a considerable number of patients. However, this does not translate into an improvement in clinical outcomes.

Computed tomography of the chest in blunt thoracic trauma: results of a prospective study

BACKGROUND

Computed tomography of the chest (CTC) is more sensitive than conventional roentgenography at detecting blunt thoracic injuries. Its effect on subsequent therapy remains incompletely characterized.

METHODS

Nine criteria believed to represent the presence of, or the potential for, significant thoracic injuries were defined, and patients were followed prospectively. Forty consecutive patients had CTC after initial evaluation. Physiologic and anatomic findings were compared, and the effect of CTC on therapy was analyzed.

RESULTS

CTC detected 76 injuries not found on plain roentgenograms, and plain roentgenograms detected 25 injuries not visible on CTC scans. Six patients had therapy changes based on CTC findings, five of which involved chest tube modification. The percentage of pulmonary contusion did not predict the need for mechanical ventilation but did correlate with physiologic contusion.

CONCLUSIONS

Blunt thoracic injuries detected by CTC infrequently require immediate therapy. If immediate therapy is needed, findings will be visible on plain roentgenograms or on clinical exam. Routine CTC in blunt trauma is not recommended but may be helpful in selected cases.

CT of blunt chest trauma in children

While trauma is still the leading cause of death in the pediatric age range, it is surprising how little the CT appearances of pediatric chest injury have been investigated in the literature. We have reviewed the CT findings of blunt chest trauma in 44 children for whom chest CT examinations were requested to investigate the extent of intrathoracic injury. We noted a propensity for pulmonary contusions to be located posteriorly or posteromedially, and for them to be anatomically nonsegmental and crescentic in shape. This is possibly attributable to the relatively compliant anterior chest wall in children. The CT appearances of other major thoracic injuries are described, including pulmonary lacerations, pneumothoraces, malpositioned chest tubes, mediastinal hematomas, aortic injury, tracheobronchial injury, hemopericardium, and spinal injuries with paraspinal fluid collections. Children demonstrating findings incidental to the actual injury yet important to the subsequent therapy are also presented. We conclude that, in the event of clinically significant blunt chest trauma, the single supine chest examination in the trauma room is insufficient to adequately identify the extent of intrathoracic injury. With the exception of concern for aortic injury for which aortography is indicated, a dynamically enhanced CT scan of the thorax should be performed as clinically significant findings may result in altered therapy.

Pulmonary Contusion in Contact Sports

In brief Computed tomography (CT) is always more precise than chest x-ray for evaluating pulmonary contusions and other forms of lung trauma. CT is also valuable in guiding treatment for patients who have pulmonary contusions. As demonstrated by two case studies, not all sports-related pulmonary contusions are minor. Supportive treatment usually consists of maintaining the patient's oxygenation, treating associated injuries, and preventing complications.

Effect of lung contusion on pulmonary hemodynamics

Our purpose was to examine changes in pulmonary hemodynamics for patients with pulmonary contusion. Pulmonary vascular resistance index (PVRI) and shunt fraction were calculated from standard measurements in 25 traumatized patients. The percent of lung volume injured, measured as air-space filling disease (ASF), was quantitated from computed tomograms using a previously described technique. The amount of reactive pulmonary vasoconstriction per unit of injury (PVRI/ASF) identified 3 groups of patients: 5 were reactors (PVRI/ASF greater than 15), 10 were weak-reactors (PVRI/ASF = 5 to 15), and 10 were nonreactors (PVRI/ASF less than 5). In the reactor group PVRI increased as the size of contusion (ASF) increased (r = 0.99). In weak-reactors PVRI also increased with the size of contusion (r = 0.93), but the slope was less pronounced. In both groups shunt fraction did not rise above 0.31. In the nonreactors, PVRI remained normal while shunt fraction increased with the extent of injury (r = 0.95). These results indicate that pulmonary vasoconstriction often occurs after pulmonary contusion. The vasoconstriction most probably represents a compensatory mechanism to limit perfusion of traumatized parenchyma, thereby minimizing increases in shunt fraction. Some patients (nonreactors) not demonstrating this response have unchecked increases in shunt fraction. This insight into the hemodynamic sequelae of pulmonary contusions may enhance our ability to provide optimal care for patients suffering from this injury.

Pulmonary contusion. Evaluation and classification by computed tomography

In thoracic trauma, as in all of medicine, diagnosis precedes therapy. Over the past 5 years, we have liberally used chest CT examinations to improve diagnosis in the severely injured patient. This approach has significantly increased our diagnostic yield and permitted early diagnosis and treatment of unsuspected injuries. Confidence in our method of quantitation has helped us to assess the severity of pulmonary parenchymal injuries. Correlation of the CT findings with histologic study has changed our concept of pulmonary contusion from that of interstitial disease to that of pulmonary laceration with blood pneumonia.