Hemomediastinum Resulting from Subclavian Artery Laceration During Internal Jugular Catheterization

The complications associated with internal jugular vein catheterization are inadvertent arterial puncture, pleural and mediastinal injuries, pneumothorax, hemothorax, and hemomediastinum. Complications caused by laceration of a subclavian artery are rare. We present a case of hemomediastinum resulting from laceration of the subclavian artery during central venous catheterization. After right internal jugular vein catheterization, the left lateral decubitus position was maintained for 6 h during surgery. The severe hypotension was first noted in the supine position after transfer to the postanesthesia care unit. Chest radiograph showed a bulging of the right upper mediastinum. During the upper half sternotomy, a 5-mm long laceration was found at the posteroinferior side of the right subclavian artery near its origin from the innominate artery.

IMPLICATIONS

The authors describe the delayed presentation of hemomediastinum resulting from subclavian artery laceration after internal jugular vein catheterization.

Trans-mediastinal gunshot wounds: are "stable" patients really stable?

Gunshot wounds that traverse the mediastinum frequently cause serious injury to the cardiac, vascular, pulmonary, and digestive structures contained within. Most patients present with unstable vital signs signifying the need for emergency operation. An occasional patient will present with stable vital signs. Work-ups for such a patient may range from surgical exploration to radiographic and endoscopic testing to mere observation. We report our experience with diagnostic work-up of the stable patient with a transmediastinal gunshot wound. All stable patients who present to our urban level I trauma center following a transmediastinal gunshot wound undergo diagnostic work-up consisting of chest radiograph, cardiac ultrasound, angiography, esophagoscopy, barium swallow, and bronchoscopy. The work-up is dependent on the trajectory of the missile. Information on these patients is kept in a prospective database maintained by the trauma attending physicians. This database was analyzed and comparisons were made using Student's t-test and the Fisher exact c2 as appropriate. Over a 68-month period, 50 stable patients were admitted following a transmediastinal gunshot wound. All of these patients had a chest radiograph followed by one or more of the above tests. 8 patients (16%) were found to have a mediastinal injury (4 cardiac, 3 vascular, and 1 tracheo-esophageal) requiring urgent operation (group 1). The remaining 42 patients (84%) did not have a mediastinal injury (group 2). There was no difference between groups with respect to blood pressure, pulse, respiratory rate, pH, base deficit, or initial chest tube output. There was one death in each group, and three complications in group 2. Patients may appear stable following a transmediastinal gunshot wound, even when they have life-threatening injuries. There is no difference in vital signs, blood gas, or hemothorax to indicate which patients have serious injuries. We advocate continued aggressive work-up of these patients to avoid missing an injury with disastrous consequences.

Reevaluation of diagnostic procedures for transmediastinal gunshot wounds

BACKGROUND

Little controversy surrounds the treatment of hemodynamically unstable patients with transmediastinal gunshot wounds (TMGSWs). These patients generally have cardiac or major vascular injuries and require immediate operation. In hemodynamically stable patients, debate surrounds the extent and order of the diagnostic evaluation. These patients can be uninjured, or can have occult vascular, esophageal, or tracheobronchial injuries. Evaluation has traditionally often included angiography, bronchoscopy, esophagoscopy, esophagography, and pericardial evaluation (i.e., pericardial window) for all hemodynamically stable patients with TMGSWs. Expansion of the use of computed tomographic (CT) scanning in penetrating injury led to a modification of our protocol. Currently, our TMGSW evaluation algorithm for stable patients consists of chest radiograph, focused abdominal sonography for trauma, and contrast-enhanced helical CT scan of the chest with directed further evaluation. The purpose of this study is to evaluate the efficiency of contrast-enhanced helical CT scan for evaluating potential mediastinal injuries and to determine whether patients can be simply observed or require further investigational studies.

METHODS

Medical records of hemodynamically stable patients admitted with TMGSWs over a 2-year period were reviewed for demographics, mechanism of injury, method of evaluation, operative interventions, injuries, length of stay, and complications. CT scans were considered positive if they contained a mediastinal hematoma or pneumomediastinum, or demonstrated proximity of the missile track to major mediastinal structures.

RESULTS

Twenty-two stable patients were studied. CT scans were positive in seven patients. Directed further diagnostic evaluation in those seven patients revealed two patients who required operative intervention. Sixty-eight percent of patients had negative CT scans and were observed in a monitored setting without further evaluation. There were no missed injuries. The hospital charges generated with the CT scan-based protocol are significantly less than with the standard evaluation.

CONCLUSION

Contrast-enhanced helical CT scanning is a safe, efficient, and cost-effective diagnostic tool for evaluating hemodynamically stable patients with mediastinal gunshot wounds. Positive CT scan results direct the further evaluation of potentially injured structures. Patients with negative results can safely be observed in a monitored setting without further evaluation.

Major mediastinal injury from crossbow bolt

We treated a 26-year-old male who sustained a self-inflicted injury to the mediastinum with a crossbow bolt. Injuries involved penetration of the sternum 1 cm below the sternomanubrial joint, right lung, pericardium, ascending aorta, right pulmonary artery, esophagus, and azygos vein. He was treated successfully with cardiopulmonary bypass and hypothermia. Exposure was achieved with a combination of a sternotomy and right thoracotomy.

Mediastinal impalement with survival: a case report

Mediastinal impalement injuries are rare and often fatal. Very few instances of survival after mediastinal impalement have been reported. We present the unusual case of an 18-year-old man who was involved in a motor vehicle crash in which a wooden fencepost intruded through the windshield and impaled him through the superior mediastinum. The patient remained hemodynamically stable and had no other significant injuries except a left pneumothorax. Arteriogram revealed a bovine aortic arch with the wooden piece passing over the aortic arch between the two brachiocephalic arteries at the precise point that a normal left common carotid artery would have been located. No other injuries were seen on arteriogram, venogram, or esophagram. The foreign body was extracted via thoracotomy along with resection of the apex of the left lung and ligation of the thoracic duct. The patient was discharged on hospital day eight and was doing quite well at one-year follow-up with no residual effects of his accident.

Cardiovascular Injuries associated with Sternal Fractures

OBJECTIVE

To find out if the presence of a sternal fracture indicates cardiac and aortic injuries and to clarify the difference between a retrosternal haematoma and widened mediastinum.

DESIGN

Retrospective study.

SETTING

Teaching hospital, Sweden.

SUBJECTS

418 patients with blunt chest trauma of whom 29 had a fractured sternum (11 with retrosternal haematoma and 18 without) and 389 did not (7 with widened mediastinum and 382 without).

MAIN OUTCOME MEASURES

Definitions, risk factors, morbidity, and mortality.

RESULTS

Retrosternal haematomas were found adjacent to many fractures and ranged in size from a few mm to 2 cm. They were more common in fractures of the body of sternum. There was no significant difference in the number of associated lesions between patients with sternal fractures with or without a retrosternal haematoma. Conversely, patients with a widened mediastinum had a higher injury severity score, longer hospital stay (p < 0.0001), and more associated lesions (p < 0.05) than those with retrosternal haematomas. Six patients still had pain 1 month after injury of whom two had injury-related long-term disability because of pain. No serious cardiac or aortic injuries were detected in this series. The early mortality in our study was 2/29 in patients with sternal fractures and 1/7 in patients with widened mediastinum.

CONCLUSIONS

Sternal fractures are more common than previously reported. An aggressive approach including early operative reduction is recommended even for a stable fracture to reduce the overhelming pain. Sternal fracture with or without retrosternal heamatoma is not a reliable indicator of cardiac and aortic injuries, while mediastinal widening is still a fairly reliable clue that should indicate further investigation.

Penetrating wounds of the torso

Penetrating trauma is on the increase as a result of interpersonal violence throughout the world. It is essential that military surgeons are familiar with such injuries and trained not only in the principles of their management, but also have first-hand operative experience before deployment in the field of conflict. More often than not, this experience is to be gained in the civilian urban setting in countries such as South Africa and the USA. The article addresses the first requirement--the principles of management--and outlines basic measures to enable those unfamiliar with penetrating wounds of the torso to make a reasonable and directed approach to dealing with these patients. It does not attempt to give definitive advice on specific injuries. It is organised according to anatomical regions, but emphasises that this is only in order to put shape to the article; penetrating injuries frequently having no respect for anatomical boundaries. Particular attention is drawn to difficult areas such as mediastinal injuries, and to modern concepts of 'damage control' surgery and the 'abdominal compartment syndrome'. The emphasis throughout is on how to get out of trouble and where particular danger spots may be anticipated. Reference will be made to the differences that may be expected within the military environment as opposed to the civilian setting, where rapid and (usually) safe evacuation to a well-equipped secure facility may not be possible. The article aims to raise the awareness of those involved in the care of patients with penetrating wounds of the torso that a methodical approach with a practised team of experienced individuals can salvage injuries which at first sight may seem terrifying or hopeless.

Significance of a widened mediastinum in blunt chest trauma patients

Eighteen blunt chest trauma patients who had mediastinal widening on chest roengenogram were studied for the correlation with traumatic ruptured of the aorta or its major branches. Seventeen patients were male and one was female. The age ranged from 18 to 39 years, mean 26.17+/-6.85SD. The Injury Severity Score (ISS) ranged from 9 to 34, mean 25.5+/-6.49SD. Fourteen patients (77.8%) sustained motorcycle accidents, 3 patients (16.7%) sustained car accidents and 1 patient (5.5%) fell from a 4 storey building. All patients underwent aortography to search for traumatic rupture of the aorta or its major branches. Six patients had computed tomography of the chest before aortography. Nine patients (50%) had normal aortography. The remaining 9 patients who had positive aortography underwent urgent thoracotomies, 8 of them had traumatic rupture of the aorta or its major branches, the remaining 1 patient had normal operative finding. Of the 8 patients who had traumatic rupture of the aorta or its major branches, 1 patient died. The mortality was 12.5 per cent. The rate of traumatic rupture of the aorta or its major branches in patients who had blunt chest trauma and widening of the mediastinum on chest roengenogram in our study was 44.4 per cent. The sensitivity of aortography for diagnosis of traumatic rupture of the aorta or its major branches was 100 per cent and the specificity was 90 per cent. On the basis of this study, we conclude that blunt chest trauma patients with widened mediastinum on chest roengenogram have a significantly high rate of traumatic rupture of the aorta or its major branches. All blunt chest trauma patients who have widened mediastinum on chest reongenogram should undergo further investigations to exclude traumatic rupture of the aorta or its major branches. We recommend aortography as the investigation of choice due to its accuracy and usefulness in management plan.

Helical computed tomographic scan in the evaluation of mediastinal gunshot wounds

BACKGROUND

The standard evaluation of mediastinal gunshot wounds usually requires angiography and either esophagoscopy or esophagography. In the present study, we have evaluated the role of helical computed tomographic (CT) scanning in reducing the need for angiographic and esophageal studies.

METHODS

This was a prospective study of patients with mediastinal gunshot wounds who were hemodynamically stable and would otherwise require angiography and esophageal evaluation. All patients underwent CT scan of the chest with intravenous contrast to delineate the missile trajectory. If the missile tract was in close proximity to the aorta, great vessels, or esophagus, then traditional evaluation with angiographic or esophageal evaluation was pursued.

RESULTS

A total of 24 patients met the inclusion criteria and underwent CT scan evaluation of their mediastinal gunshot wounds. One patient was taken for sternotomy to remove a missile embedded in the myocardium solely on the basis of the result of the CT scan. Because of proximity of the bullet tract, 12 patients required additional evaluation with eight angiograms and nine esophageal studies. One of these patients had a positive angiogram (bullet resting against the ascending aorta) and underwent sternotomy for missile removal; all other studies were negative. The remaining 11 patients were found to have well-defined missile tracts that approached neither the aorta nor the esophagus, and no additional evaluation was pursued. There were no missed mediastinal injuries in this group. Overall, 12 of 24 patients (50%) had a change in management (either received an operation or avoided additional radiographic or endoscopic evaluation) on the basis of the CT scan.

CONCLUSION

The helical CT scan provides a rapid, readily available, noninvasive means to evaluate missile trajectories. This permits accurate assessment of potential mediastinal injury and reduces the need for routine angiographic and esophageal studies.

[Application of spiral computerized tomography in the study of traumatic lesions of the thoracic aorta]

PURPOSE

Acute thoracic aortic injuries account for up to 10-20% of fatalities in high-speed deceleration road accidents and have an estimated immediate fatality rate of 80-90%. Untreated survivors to acute trauma (10-20%) have a dismal prognosis: 30% of them die within 6 hours, 40-50% die within 24 hours, and 90% within 4 months. We investigated the diagnostic accuracy of Helical Computed Tomography (Helical CT) in acute traumatic injuries of the thoracic aorta, and the role of this technique in the diagnostic management of trauma patients with a strong suspicion of aortic rupture.

MATERIAL AND METHODS

We compared retrospectively the chest Helical CT findings of 256 trauma patients examined June 1995 through August 1999. All patients underwent a plain chest radiograph in supine recumbency when admitted to the Emergency Room. Chest Helical CT examinations were performed according to trauma score, to associated traumatic lesions and to plain chest radiographic findings. All the examinations were performed with no intravenous contrast agent administration and the pitch 2 technique. After a previous baseline study, contrast-enhanced scans were acquired with pitch 1 in 87 patients. All examinations were assessed for the presence of mediastinal hematoma, periaortic hematoma, traumatic pseudodiverticulum, irregular aortic wall or contour and intimal flap as signs of aortic rupture.

RESULTS

Helical CT showed thoracic aortic lesions in 9 of 256 patients examined. In all the 9 cases we found a mediastinal hematoma and all of them had positive plain chest radiographic findings of mediastinal enlargement. Moreover, in 6 cases aortic knob blurring was also evident on plain chest film and in 5 cases depressed left mainstem bronchus and trachea deviation rightwards were observed. All aortic lesions were identified on axial scans and located at the isthmus of level. Aortic rupture was always depicted as pseudodiverticulum of the proximal descending tract and intimal flap. We also found periaortic hematoma in 6 cases and intramural hematoma in 1 case. There were no false positive results in our series: 7 patients with Helical CT diagnosis of aortic rupture were submitted to conventional aortography that confirmed both type and extension of the lesions as detected by Helical CT, and all findings were confirmed by gross inspection at surgery. No false negative results have been recorded so far: untreated aortic ruptures are fatal within 4 months in 90% of patients, or they may evolve into chronic pseudoaneurysm in about 5% of survivors.

CONCLUSIONS

In our experience Helical CT had much higher diagnostic sensitivity and specificity than plain chest radiography. In agreement with larger published series, in our small one the diagnostic accuracy of Helical CT was 100% in the evaluation of traumatic aortic ruptures. Moreover, Helical CT is faster and less invasive than conventional aortography, which makes this diagnostic modality increasingly used and markedly improves the management of the serious trauma patient. The more widespread use of this diagnostic tool has permitted to standardize the technique and now Helical CT can be used not only as a screening modality for patients that undergo digital aortography, but also as a reliable diagnostic method for surgical planning.

Transmediastinal gunshot injuries

BACKGROUND

Transmediastinal gunshot injuries are a rarely reported injury. Until recently, assessment of the thoracic aorta by angiography preceded the investigation of the esophagus. This order has been recently debated.

METHODS

There were 118 patients with potential transmediastinal injuries included in this retrospective study. Unstable patients who were unresponsive to resuscitation were taken to the operating room without previous investigation. Stable patients were routinely investigated initially for injury of the aorta and then for injury of the esophagus.

RESULTS

There were 51 patients who underwent urgent thoracotomy/sternotomy. In 27, the hemorrhage was of mediastinal origin; 17 of these patients died of intraoperative bleeding. Eight of the patients had aortic injury, and only one of this group survived. There were 57 stable patients who were investigated initially for injury of the aorta by angiography. It was positive in only one patient who underwent an operation with good results. An investigation of the esophagus followed and revealed esophageal injury in 17 patients. All of them were treated operatively, 15 of them with satisfactory outcome.

CONCLUSIONS

Angiography should at present precede esophageal investigations. There is a need for shortening the time between admission and operation. Other modalities that could expedite the investigation of the thoracic aorta and the esophagus should be prospectively evaluated in multi-center studies.

Nonaortic mediastinal injuries from blunt chest trauma

In addition to traumatic aortic injuries (TAI), blunt chest trauma may damage other structures in the mediastinum, including the tracheobronchial tree, the heart and pericardium, and rarely the esophagus. Tracheobronchial injuries may be difficult to separate radiographically from accompanying parenchymal lung injuries. Experience with diagnosis by computed tomography (CT) is still limited. Cardiac injuries often require emergent surgery before extensive imaging can be done. Some patients, usually those with chamber ruptures of the right heart, survive long enough to receive a chest CT, at which time hemopericardium can be detected. Upper esophageal injuries may occur in conjunction with lower cervical or upper thoracic spine injures. Distal esophageal injuries are rarely caused by blunt trauma.

Transmediastinal gunshot wounds: a prospective study

OBJECTIVE

To evaluate admission systolic blood pressure (SBP) in the emergency center (EC) as a means by which patients with transmediastinal gunshot wounds (TM-GSWs) can be triaged to the operating room versus further diagnostic evaluation.

METHODS

A prospective case series presenting concurrent data collected for 68 consecutive patients with TM-GSWs admitted to one urban trauma center over a 4.5-year period. For purposes of analysis, patients were assigned to the following groups based on SBP in the EC: group I, SBP > 100 mm Hg; group II, SBP from 60 to 100 mm Hg; group III, SBP < 60 mm Hg.

RESULTS

The management and outcomes of 68 patients with a mean age of 29 years were evaluated. For patients in group I (n = 20), TM-GSW was diagnosed by findings on x-ray film for 15 patients (75%), at physical examination for 4 patients (20%), and at operation for 1 patient (5%). Indications for immediate operation were found in five patients (25%), whereas further diagnostic evaluation prompted operation for three additional patients. Only one patient developed persistent hypotension from neurogenic shock. There were two deaths from late complications. In patients in group II (n = 16), TM-GSW was diagnosed by findings on x-ray film for 9 patients (56%), at physical examination for 5 patients (31%), and at operation for 2 patients (13%). Six patients with persistent hypotension had indications for immediate operation, whereas further diagnostic evaluation in the remaining patients, who became hemodynamically normal during resuscitation, prompted operation in an additional two patients. There were two intraoperative deaths. For the patients in group III (n = 32), six patients with signs of life underwent immediate operation with one intraoperative death, seventeen patients required EC thoracotomy with 100% mortality, and nine patients were pronounced dead in the EC without an attempt at operation.

CONCLUSION

The diagnosis of TM-GSW for patients in groups I and II is confirmed by finding at physical examination and on chest x-ray films in 90% of cases. In the absence of obvious bleeding, patients with TM-GSWs and SBP > 100 mm Hg may safely undergo further diagnostic evaluation. Sixty percent of such patients did not require an operation. All patients with TM-GSWs and SBP < 60 mm Hg (group III) require immediate operation. For patients with TM-GSWs, SBP from 60 to 100 mm Hg (group II), and without obvious bleeding, it is the response to resuscitation and the results of further diagnostic evaluation that determine the need for operation. Fifty percent of such patients did not require operation.

[The role of computed tomography in gunshot lesions of the chest. The authors' personal experience]

PURPOSE

CT is a valuable tool in assessing thoracic gunshot wounds. CT is also the method of choice in emergency, because it permits rapid depiction of bullet damage to the chest and to other body districts. This in turn permits correct assessment of the main thoracic injuries, plus adequate and prompt planning of surgical treatment or support intensive care. We report on the role of CT in diagnosing the complex pleuropulmonary, cardiovascular and thoracic wall injuries caused by gunshot wounds, with their specific and acute signs which differ greatly from those of other types of chest trauma.

MATERIAL AND METHODS

In the last 4 years, we observed 76 cases of gunshot injury, twenty-six of them involved the chest. The patients, 25 men and 1 woman (mean age: 32 years, range: 17-48), were all submitted to emergency CT with i.v. contrast agent injection and the CT-angiography technique. The reanimator was always present to monitor the patients' vital functions and shock state. CT of the chest was integrated with CT of the abdomen and pelvis in 4 cases and with CT of the skull in 3 cases, to detect associated bullet wounds if any.

RESULTS

The most frequent CT finding was lung parenchyma tear and bruise (25 cases), followed by hemothorax (18 cases) and subcutaneous chest wall emphysema (9 cases). Pneumothorax was seen in 5 cases, associated with hemothorax in 6; rib injuries were found in 7 cases; pneumomediastinum was found in 4 cases and areas of pulmonary atelectasis in 3; the diaphragm was ruptured in 4 cases. CT showed spinal involvement in 11 patients, with injury of D3 and D5 in 4 and 3 cases, respectively; signs of interrupted spinal marrow were found in 7 cases. Damage from gunshot wounds was detected in the liver, spleen, skull and limbs in 3, 2, 3 and 10 cases, respectively.

DISCUSSION AND CONCLUSIONS

Chest radiography shows major gunshot wound damage to the chest and lungs, except for heart injuries and minimal pneumothorax. When abdominal and skull injuries are associated, CT should be the method of choice because it permits prompt and panoramic assessment of the severity of pulmonary and extrathoracic damage. This results in prompt and targeted treatment, avoiding unnecessary delays which may damage the patient further.

Mediastinal perforation and contralateral hemothorax by a chest tube

Tube thoracostomy is an invasive and common procedure that is often life-saving, but by no means innocuous. We describe herein a case of chest trauma in which the chest tube crossed through the mediastinum between aorta and esophagus and penetrated the contralateral pleural cavity causing mild hemothorax. A literature search has failed to identify a similar case: the misplacement was detected in a control radiograph which led to early adjustment of the tube and no sequalae.

Routine helical computed tomographic evaluation of the mediastinum in high-risk blunt trauma patients

BACKGROUND

The indications and method of evaluation of the mediastinum in blunt deceleration trauma are controversial and vary among centers. Most centers practice a policy of angiographic evaluation only in the presence of an abnormal mediastinum on chest radiography. Routine aortography in the absence of any mediastinal abnormality is not widely practiced. Helical computed tomographic (CT) scan has been successfully used in recent studies in the evaluation of the thoracic aorta.

OBJECTIVE

To determine the role of routine helical CT scan evaluation of the mediastinum in patients involved in high-speed deceleration injuries, irrespective of chest radiographic findings.

DESIGN

A prospective study over a 1-year period. Included in the study were patients with high-speed deceleration injuries who required CT evaluation of the head or abdomen. This group of patients underwent routine helical CT evaluation of the mediastinum irrespective of chest radiographic findings.

SETTING

Large, urban, academic level I trauma center.

RESULTS

A total of 112 trauma patients fulfilled the criteria for study inclusion. Overall, there were 9 patients (8.0%) with aortic rupture. Four (44.4%) of these patients had a normal mediastinum on the initial chest x-ray film and the diagnosis was made by CT scan. The CT scan was diagnostic in 8 of the aortic ruptures (intimal tear or pseudoaneurysm) and was suggestive of aortic injury but not diagnostic in 1 patient with brachiocephalic artery injury. In 42 patients (37.5%), there was a widened mediastinum: an aortic rupture was diagnosed in 5 of them (11.9%) and a spinal fracture in 9 (21.4%). One patient had both aortic rupture and spinal injury.

CONCLUSIONS

The incidence of aortic injury in patients with high-speed deceleration injury is high. A significant proportion of patients with aortic injury have a normal mediastinum on the initial chest radiograph. There is a high incidence of spinal injuries in the presence of a widened mediastinum. We recommend that all trauma patients with high-risk deceleration injuries undergo routine helical CT evaluation of the mediastinum irrespective of chest radiographic findings.