Noncorrelation between thoracic skeletal injuries and acute traumatic aortic tear

[Traumatic injuries of the descending thoracic aorta apart from the isthmus: diagnosis and therapeutic approach]

Lesions involving the descending thoracic aorta apart from isthmus are rare and less known by anesthetists. We report the clinical course of two severely injured patients who sustained a thoracic aortic rupture in whom favorable outcome was achieved with endovascular treatment. Mechanisms, diagnosis and therapeutics aspects of these rare lesions are discussed according to literature.

Traumatic vertebral fractures with concomitant fractures of the first rib

OBJECTIVE

To investigate the characteristics of patients with traumatic vertebral fractures and concomitant fractures of the first rib and their management.

METHODS

From January 2001 to December 2010, 17/3142 patients (0.5%) with traumatic vertebral fractures who presented to our hospitals had concomitant fractures of the first rib.

RESULTS

The study included 14 men (82.4%) and 3 women (17.6%) patients of age 32-57 years (mean, 46.6 years). The mechanisms of trauma were falls from heights in seven, motor vehicle accidents in five and direct collisions with blunt objects in five. Thirteen patients (76.5%) presented initially with pulmonary complications after sustaining trauma. Three patients sustained one rib fracture, two three rib fractures, three four rib fractures and 10 >  five rib fractures. The injuries were right-sided in three cases, left-sided in three and bilateral in eleven. Four patients (23.5%) presented with craniocerebral injuries. According to the American Spinal Injury Association (ASIA) classification, 10 patients (58.8% of the total study group) had motor and sensory deficits (ASIA A-D). There were no vascular injuries or deaths.

CONCLUSION

Traumatic vertebral fractures with concomitant fractures of the first rib are associated with multisystem injuries, but not always with morbidity and mortality. A multidisciplinary approach, early diagnosis, appropriate treatment and observation in the intensive care unit may prevent morbidity and/or mortality.

The significance of first rib fractures in children

PURPOSE

The purpose of the study was to determine if first rib fractures are associated with an increased incidence of thoracic vascular injury in pediatric patients.

METHODS

The medical records of all children diagnosed with a first rib fracture or a central vascular injury after blunt trauma treated at a state-designated level 1 pediatric trauma center from 2000 to 2009 were reviewed.

RESULTS

Thirty-three children (0.27% of patients; mean age, 10.9 ± 0.9 years) were identified with either a first rib fracture or thoracic vascular injury owing to blunt trauma. Thirty-two children had a first rib fracture, and only 1 child (3%) had significant thoracic vascular injury. Mediastinal abnormalities (indistinct aortic knob) were identified in 3 children, 2 with first rib fracture on initial chest radiograph. Despite a normal cardiovascular examination result, 25 (74%) children with a normal mediastinum on screening chest radiograph underwent computed tomography. No child with a normal mediastinum on initial chest radiograph was found to have associated intrathoracic injuries requiring further intervention. In children with first rib fractures and a normal mediastinum by screening chest x-ray, the negative predictive value for thoracic vascular injury was 100%.

CONCLUSIONS

Children with first rib fractures without mediastinal abnormality on chest radiograph require no further workup for thoracic vascular injury.

Acute traumatic aortic injury: imaging evaluation and management

Despite recent advances in prehospital care, multidetector computed tomographic (CT) technology, and rapid definitive therapy, trauma to the aorta continues to be a substantial source of morbidity and mortality in patients with blunt trauma. The imaging evaluation of acute aortic injuries has undergone radical change over the past decade, mostly due to the advent of multidetector CT. Regardless of recent technologic advances, imaging of the aorta in the trauma setting remains a multimodality imaging practice, and thus broad knowledge by the radiologist is essential. Likewise, the therapy for acute aortic injuries has changed substantially. Though open surgical repair continues to be the mainstay of therapy, percutaneous endovascular repair is becoming commonplace in many trauma centers. Here, the historical and current status of imaging and therapy of acute traumatic aortic injuries will be reviewed.

Diagnostic Dilemmas and Current Controversies in Blunt Chest Trauma

Blunt chest injuries are common encounters in the emergency department. Instead of a comprehensive review of the management of all chest injuries, this review focuses on injuries that can be difficult to diagnose and manage, including blunt aortic injury, cardiac contusion, and blunt diaphragmatic injury. This review also discusses some recent controversies in the literature regarding the use of prophylactic antibiotics for tube thoracostomy and the optimal management of occult pneumothorax. The article concludes with a discussion of the management of rib fractures in the elderly.

Chest Wall, Lung, and Pleural Space Trauma

Chest radiographs frequently underestimate the severity and extent of chest trauma and, in some cases, fail to detect the presence of injury. CT is more sensitive than chest radiography in the detection of pulmonary, pleural, and osseous abnormalities in the patient who has chest trauma. With the advent of multidetector CT (MDCT), high-quality multiplanar reformations are obtained easily and add to the diagnostic capabilities of MDCT. This article reviews the radiographic and CT findings of chest wall, pleural, and pulmonary injuries that are seen in the patient who has experienced blunt thoracic trauma.

Management of Blunt Thoracic Aortic Injury

Blunt traumatic aortic transection (TAT) is an uncommon injury in clinical practice that is associated with a high morbidity and mortality. The approach to patients with such an injury is controversial with specific regard to the most effective diagnostic tools, timing of surgical intervention and mechanisms of spinal cord protection. Chest X-ray with widening of the mediastinum is unreliable as a diagnostic tool. Contrast enhanced helical CT Scan has replaced the traditional angiography as the screening diagnostic tool of choice Emergency thoracotomy and repair should be reserved for the few patients with isolated TAT without any major concomitant injuries. Delayed management approach with aggressive blood pressure control and serial radiological monitoring is a safe and recommended option for those with severe concomitant injuries or other medical co-morbidity that puts surgery at high risk. Active augmentation of the distal perfusion pressure during cross clamp offers the best protection against development of paraplegia during open surgical repair. Endovascular stenting offers a minimally invasive method of treatment but the long-term durability of the endovascular stent is still unknown. We feel that the greater feasibility of the endovascular repair in the acute phase of the thoracic injury is an advantage over the open surgery and should be the treatment of choice in patients with severe concomitant injuries.

Traumatische Aortenverletzungen bei polytraumatisierten Patienten

Herein we report our results of treatment of traumatic aortic ruptures in severely injured patients with either open surgery or endovascular stent graft repair. Data were analyzed retrospectively from the trauma registry of the DGU (Deutsche Gesellschaft fur Unfallchirurgie) over a time period from 1993 through 2002. All patients with traumatic rupture of the aorta were included and analyzed for injury severity (ISS), blood pressure (mmHg), hemoglobin (mg/%), and AIS (Abbreviated Injury Score) of the thoracic, abdominal, and upper extremity regions. Patients treated between 1998 and 2002 were further examined (operation within 24 h, duration of intervention, blood transfusion, and lethality with regard to either open surgical or endoluminal stent graft repair). Of 14,110 patients, 100 (0.7%) suffered from acute aortic rupture. Mean age was 38 years (+/-19) with an inhospital lethality of 39% (n=39). Mean ISS was 41 (+/-14); 36 patients were treated by open surgery and 5 patients by a stent-assisted endoluminal procedure. Lethality was 17% for open surgery and 0% for stent graft repair. Endovascular approach to traumatic rupture of the aorta is feasible and safe. It has been shown to reduce inhospital lethality and may offer an alternative to open surgery for severely injured patients.

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.

Seat belts are more effective than airbags in reducing thoracic aortic injury in frontal motor vehicle crashes

BACKGROUND

Airbags reduce the probability of death in frontal collisions, but the effect is small compared with seat belts. Little is known about the influence of seat belts and airbags on the incidence of thoracic aortic injury (TAI).

METHODS

The National Automotive Sampling System database was queried for the years 1993 to 1998 to determine the impact of seat belts and airbags on the incidence of TAI in survivors of frontal motor vehicle crashes. Proportions were compared using the two-sample Z test.

RESULTS

Seat belts prevent TAI regardless of airbag deployment. The effect of airbags is limited to those wearing seat belts. In frontal collisions without seat belt use, airbag deployment does not alter TAI incidence.

CONCLUSION

Seat belts are considerably more effective in preventing TAI than airbags after frontal motor vehicle crashes. Prevention efforts should continue to emphasize the use of active restraints. Restraint use should be considered a risk factor in evaluating patients for potential TAI.

[Traumatic rupture of the aortic isthmus revealed by a mesenteric infarct]

The traumatic rupture of the aortic isthmus is one of the worst complication due to high speed motor vehicle accidents. When death is not the immediate consequence of this lesion, the initial clinical signs are not very clear. The present article demonstrates the case of a 23-year-old patient, victim of a car accident. A traumatic aortic rupture was actually diagnosed after the unusual discovery of a mesenteric infarct. In this case report, the mesenteric infarct mechanism can be controversed, and an emphasis should be put on an early aortic lesion diagnosis and repair in order to avoid any ischaemic complications.

The influence of superficial soft tissues and restraint condition on thoracic skeletal injury prediction

The purpose of this study is to evaluate the hard tissue injury-predictive value of various thoracic injury criteria when the restraint conditions are varied. Ten right-front passenger human cadaver sled tests are presented, all of which were performed at 48 km/h with nominally identical sled deceleration pulses. Restraint conditions evaluated are 1) force-limiting belt and depowered airbag (4 tests), 2) non-depowered airbag with no torso belt (3 tests), and 3) standard belt and depowered airbag (3 tests). Externally measured chest compression is shown to correspond well with the presence of hard tissue injury, regardless of restraint condition, and rib fracture onset is found to occur at approximately 25% chest compression. Peak acceleration and the average spinal acceleration measured at the first and eighth or ninth thoracic vertebrae are shown to be unrelated to the presence of injury, though clear variations in peaks and time histories among restraint conditions can be seen. The maximum viscous criterion is found to correspond with injury, but only because it increases with the maximum chest compression. A simple analytical study is presented to elucidate the observed restraint condition dependence of rib fracture location and the restraint insensitivity of injurious maximum chest compression. Computed tomography images of a loaded torso are presented to show the load-distributing effect of the soft tissues superficial to the rib cage.

Guidelines for the diagnosis and management of blunt aortic injury: an EAST Practice Management Guidelines Work Group

In summary, BAI is a lethal result of severe blunt trauma. It should be considered in all patients who sustained injury by a deceleration or acceleration mechanism, especially in the face of physical or radiographic findings suggestive of mediastinal injury. Angiography remains the "gold standard" for diagnosis, although CT scanning is taking more of a role, especially for screening. Diagnosis should be followed by prompt surgical repair using some method of distal perfusion to minimize renal and spinal cord ischemia. If prompt repair is not feasible because of other injuries or comorbidities, medical control of blood pressure is warranted in the interim.

Thoracic aortic injury: how predictive is mechanism and is chest computed tomography a reliable screening tool? A prospective study of 1,561 patients

BACKGROUND

Thoracic aortic injury (TAI) is a devastating condition in which prompt recognition can obviate morbidity and mortality. It is a long-held belief that TAI is more likely when there is a "major mechanism of injury." The purposes of this prospective study were to determine mechanism characteristics that are predictive of TAI and to evaluate chest computed tomography (CT) as a screening tool for TAI.

METHODS

Over a 5 1/2 year period, blunt chest trauma patients at two Level I trauma centers were evaluated for potential TAI. Patients were assigned mechanism and radiograph scores from 1 (low suspicion for TAI) to 5 (very high suspicion for TAI). Immediate aortography was obtained when suspicion for TAI was very high. The remaining patients were evaluated with contrast-enhanced chest CT. Confirmatory aortography was obtained on all positive chest CT scans and on all patients with mechanism scores of 4 or 5 even if the CT was negative. Mechanism and radiographic data were correlated with the results of aortic imaging.

RESULTS

Of the 1,561 patients evaluated for TAI, 30 aortic injuries were found. The assessment of mechanism was imperfect with a reliance on often incomplete and subjective data. The subjective mechanism score proved to be the most useful predictor of TAI. Radiographic scores were useful but insensitive for intimal injuries. Computed tomography was found to have 100% and 100% NPV for TAI.

CONCLUSION

Considering the inherent difficulties in identifying patients at risk for TAI and the effectiveness of chest CT as a screening tool for aortic injury, we recommend liberal use of chest CT in blunt chest trauma. Guidelines for determining the need for aortic imaging are outlined.

Imaging in thoracic trauma: the trauma surgeon's perspective

Thoracic trauma is a common cause of significant disability and mortality. Most thoracic injury in developed countries results from motor vehicle crashes (MVC). Imaging of patients with thoracic trauma must be accurate and timely to avoid preventable death. Trauma surgeons prioritize imaging options based on the patient's hemodynamic status, associated injuries, and age. The screening test for the detection of life-threatening thoracic injury is the supine anteroposterior (AP) chest radiograph. Rib fractures are a marker for serious associated injuries, including abdominal injuries. Rib fractures are especially ominous in children and the elderly. Thoracic aortic injury is associated with high-speed mechanisms of injury and can occur in the absence of radiographic signs. Chest computed tomography (CT) can be used as a screening and diagnostic tool for suspected aortic injury. Aortography is reserved for patients with high suspicion of aortic injury or for confirmation of CT scan diagnosis.

Helical CT grading of traumatic aortic injuries. Impact on clinical guidelines for medical and surgical management

Helical CT is a reliable method for screening patients with blunt chest trauma for vascular and visceral injuries. Thoracic aortic injuries detected by CT examination affect the immediate clinical management and patient triage. This article describes the clinical indications and imaging protocols for helical CT of the chest used to detect aortic injuries, provides a grading system of the range of aortic injuries demonstrated by CT, and discusses the clinical management decisions that should be considered based on the CT grade of the aortic injury.

Evaluation of the patient with blunt chest trauma: an evidence based approach

The patient who has sustained blunt trauma to the chest can present a diagnostic challenge to the emergency physician. There are several diagnostic modalities available for treating life-threatening injuries to these patients. The authors review published studies to support the use of these tests in diagnosing injuries from blunt thoracic trauma. The article focuses chiefly on two current areas of controversy, the diagnosis of blunt aortic and blunt myocardial injury. Finally, the authors make recommendations for the use of various tests based on the available evidence.

The epidemiology of thoracic aortic injuries in pedestrians

BACKGROUND

Traumatic rupture of the thoracic aorta is recognized as a common cause of occupant death after rapid deceleration in motor vehicle collisions. The incidence of thoracic aorta rupture in pedestrian victims of vehicular collisions, however, is unknown. This study focuses on the epidemiology of injury to the thoracic aorta in pedestrian vehicular collisions.

METHODS

We performed a retrospective analysis of all pedestrian fatalities and survivors of rupture of the thoracic aorta during a 6-year period at a regional Level I trauma center and medical examiner's office.

RESULTS

There were 220 pedestrian fatalities during the study period. Laceration of the thoracic aorta was noted in 28 of the 220 pedestrian victims (12.7%). Two additional pedestrians survived laceration of the thoracic aorta, for a mortality of 94%. Hospital mortality was 66% (4 of 6). The comparative hospital mortality for patients with rupture of the thoracic aorta secondary to motor vehicle collision was 42%.

CONCLUSION

The incidence of thoracic aortic injury in pedestrian fatalities of 12.7% is comparable with previous reports of motor vehicle collision fatalities. Because of the presence of increased associated injuries, pedestrians have a significantly higher mortality. Severely injured pedestrians are at a similar risk to motor vehicle occupants for a life-threatening injury of the thoracic aorta.