Advances in the diagnosis and treatment of thoracic trauma

Surgical management of chest injuries in patients with multiple and/or severe trauma- a systematic review and clinical practice guideline update

PURPOSE

Our aim was to update evidence-based and consensus-based recommendations for the surgical and interventional management of blunt or penetrating injuries to the chest in patients with multiple and/or severe injuries on the basis of current evidence. This guideline topic is part of the 2022 update of the German Guideline on the Treatment of Patients with Multiple and/or Severe Injuries.

METHODS

MEDLINE and Embase were systematically searched to May and June 2021 respectively for the update and new questions. Further literature reports were obtained from clinical experts. Randomised controlled trials, prospective cohort studies, cross-sectional studies and comparative registry studies were included if they compared interventions for the surgical management of injuries to the chest in patients with multiple and/or severe injuries. We considered patient-relevant clinical outcomes such as mortality, length of stay, and diagnostic test accuracy. Risk of bias was assessed using NICE 2012 checklists. The evidence was synthesised narratively, and expert consensus was used to develop recommendations and determine their strength.

RESULTS

One study was identified. This study compared wedge resection, lobectomy and pneumonectomy in the management of patients with severe chest trauma that required some form of lung resection. Based on the updated evidence and expert consensus, one recommendation was modified and two additional good practice points were developed. All achieved strong consensus. The recommendation on the amount of blood loss that is used as an indication for surgical intervention in patients with chest injuries was modified to reflect new findings in trauma care and patient stabilisation. The new good clinical practice points (GPPs) on the use of video-assisted thoracoscopic surgery (VATS) in patients with initial circulatory stability are also in line with current practice in patient care.

CONCLUSION

As has been shown in recent decades, the treatment of chest trauma has become less and less invasive for the patient as diagnostic and technical possibilities have expanded. Examples include interventional stenting of aortic injuries, video-assisted thoracoscopy and parenchyma-sparing treatment of lung injuries. These less invasive treatment concepts reduce morbidity and mortality in the primary surgical phase following a chest trauma.

“Shot to the Heart”: Case Report and Concise Review of Cardiac Gunshot Injury

Penetrative cardiac injury can often result in life-threatening sequelae such as myocardial contusion or rupture, coronary vessel and valvular damage, pericardial effusion with tamponade, and arrhythmias of which gunshot injury is a chief culprit. We report a case of a suspected acute coronary syndrome after a cardiac gunshot injury that was conservatively managed.

Thoracic trauma: principles of early management

Thoracic trauma remains an important cause of early and late mortality in the injured patient. This review provides an overview of the emergency room management of thoracic trauma, amplifying the approach and principles of Advanced Trauma Life Support. The presentation, pathophysiology, diagnosis and treatment of the 12 most significant thoracic injuries are described. Focusing on emergency room management, and using the concept of the ‘lethal six’ and ‘hidden six,’ appropriate management strategies are detailed.

Anesthetic Considerations for Thoracic Trauma

The thoracic cavity encompasses three vital organ systems: the lungs with the major airways, the heart with the major blood vessels, and the spinal cord. Therefore, traumatic injury to the thoracic cavity presents a unique clinical challenge to the anesthesiologist. Itstems from the gravity of the patients' situation, the need to rapidly diagnose and treat cardiopulmonary injuries, and to coordinatethese steps with a multidisciplinary trauma team. It is importanttobe well prepared and to review the fundamentals of securing an airway in many different traumatic scenarios. Good communication between team members is the key to a positive outcome. The anesthesiologist, therefore, may play a key role in airway management, diagnosis, respiratory management, and pain management throughout the perioperative continuum of the thoracic trauma patients' care.

Cardiac trauma during teenage years

The spectrum of blunt cardiac trauma ranges from asymptomatic myocardial contusion to fatal cardiac arrhythmias and/or cardiac rupture. Although cardiac rupture is common in fatal traffic accidents, these patients rarely reach hospital care. Insignificant blunt cardiac injury during sports may cause fatal arrhythmia in teens. Penetrating cardiac trauma is fairly common in the United States, encountered frequently in major urban centers. Most cases are dead at the scene and never reach hospital. The incidence of cardiac sequelae in survivors is high, and these patients should be evaluated with early and late echocardiography to detect anatomic or functional cardiac involvement.

[Surgical accesses to the major mediastinal vessels in thoracic trauma]

Trauma is the most common cause of death in the economically active population and thoracic trauma is directly or indirectly responsible for one quarter of these deaths. Lesions to the large thoracic vessels are associated with immediate or early death in the hospital setting. Patients admitted alive can be classified as stable or unstable. The access route to be elected for management of these veins will depend on this status, as well as on the anatomical particularities of the patient, which may require combined incisions for adequate access. This article provides a review and discussion of lesions to these structures as well as access routes to them.

Penetrating cardiac injury: a review

Cardiac injury presents a great challenge to the emergency resident because these injuries require urgent intervention to prevent death. Sometimes serious cardiac injury may manifest only subtle or occult symptoms or signs. As there is an epidemic of cardiac injuries in Kashmir valley due to problems of law and order, we herein present a review on management of such injuries.

Supporting the early use of echocardiography in blunt chest trauma

This case reports a very unusual mechanism of cardiac rupture following an episode of multiple blunt chest trauma. The patient, a professional jockey, was trampled by horses, and although shocked on hospital admission, he did not present with signs and symptoms that were consistent with cardiogenic shock. This case highlights the difficult and subjective nature of clinical examination in emergency situations when dealing with cases of acute cardiac tamponade. It further emphasises the lack of sensitivity of traditional trauma imaging and investigative approaches such as the standard anteroposterior chest X-ray and electrocardiogram. The diagnosis of acute cardiac tamponade was not made until tertiary-care-centre arrival, when ultrasound technology in the form of bedside echocardiography was used, facilitating emergency surgery to repair a ruptured left ventricle. It is hoped that the sharing of this case will alert fellow clinicians to this uncommon but possible mechanism of cardiac rupture and subsequent tamponade, encourage the early use of echocardiography at the bedside in hypotensive blunt chest trauma cases and reinforce the principles of the Advanced Trauma Life Support course in treating trauma victims.

ACR Appropriateness Criteria(®) blunt chest trauma--suspected aortic injury

The purpose of these guidelines is to recommend appropriate imaging for patients with blunt chest trauma. These patients are most often imaged in the emergency room, and thus emergency radiologists play a substantial role in prompt, accurate diagnoses that, in turn, can lead to life-saving interventions. The ACR Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. Imaging largely focuses on the detection and exclusion of traumatic aortic injury; a large proportion of patients are victims of motor vehicle accidents. For those patients who survive the injury and come to emergency radiology, rapid, appropriate assessment of patients who require surgery is paramount.

Profile of missile-induced cardiovascular injuries in Kashmir, India

BACKGROUND

Missile cardiovascular injuries have taken an epidemic proportion in Kashmir valley since the eruption of militancy in 1990. Present study was undertaken to analyse the pattern, presentation and management of missile cardiovascular injuries.

PATIENTS AND METHODS

Three hundred and eighty-six patients with missile cardiovascular injuries since Jan 1996 to Oct 2008 were studied retrospectively. All patients of cardiovascular injuries due to causes other than missiles were excluded from the study.

RESULTS

All patients of missile cardiac injuries were treated by primary cardiorrhaphy. Right ventricle was the most commonly affected chamber. Left anterior thoracotomy was most common approach used. Most of the patients of missile vascular group were treated by reverse saphenous vein graft or end-to-end anastomosis. Most common complication was wound infection (20.83%) followed by graft occlusion (1.94%) in missile vascular group. Amputation rate was 4.66%. Amputation rate was higher in patients with delay of >6 hours and associated fractures.

CONCLUSION

Missile cardiac injuries should be operated early without wasting time for investigations. Clinical status at arrival, time interval till management, nature of injury and associated injuries, tell upon the mortality. Missile vascular injury needs prompt resuscitation and revascularization at the earliest. Time interval till revascularization and associated fractures has a bearing on mortality and morbidity.

Traumatic aortic injury: computerized tomographic findings at presentation and after conservative therapy

OBJECTIVE

To determine the computerized tomographic (CT) findings in traumatic aortic injury (TAI) at presentation and after conservative management.

METHODS

Institutional review board-approved retrospective review of trauma registry during a 6-year period identified class 1 or 2 trauma patients with TAI. The CT findings were correlated with patient outcome.

RESULTS

Forty-eight of 3350 patients had TAI. Seven had TAI limited to the abdominal aorta. Twenty-nine of 48 had early (12) or delayed (17) aortic repair. Common abnormalities were pseudoaneurysms (69%) and intramural hematoma (IMH) (65%). Forty-one of 48 TAI were confirmed on endovascular imaging or surgery. Subsequent CT was available in those who had delayed repair (n = 9) or conservative management (10) and showed stable pseudoaneurysms with resolving IMH (n = 11), resolving IMH (n = 4), intimal flap (n = 2), aortic thrombus (n = 1), and dissection (n = 1).

CONCLUSIONS

Traumatic aortic injury is rare. It commonly involves thoracic aorta with pseudoaneurysm and IMH. Significant TAI in stable patients remains stable on follow-up imaging. Minor TAI may resolve with conservative therapy.

Porcine traumatic lung injury model induced by hilum clamping

OBJECTIVE

To establish a temporary pulmonary hilum clamping model for thoracic damage control surgery, as well as to determine the safety time latitude of this manipulation.

METHODS

Pigs were anaesthetised and instrumented with a thermodilution cardiac output catheter. The left pulmonary hilum was clamped with a urethral catheter after thoracotomy, maintained for three different time periods (n=6 for each group), 90min (C90), 120min (C120) and 150min (C150) and then unclamped. Haemodynamic data were recorded and the serum samples were collected for D-dimer detection and other haematological analysis. A 1-cm(3) pulmonary tissue of the left lower lobe was also obtained for histological study before clamping, at the end of clamping and at 0.5, 1, 1.5, 2 and 4h after unclamping.

RESULTS

Postoperative survival rate in each group of the pigs was as follows: 100% (all six) of C90, 83.3% (five of six) of C120, and 33.3% (two of six) of C150. Blood pressure (BP) and heart rate (HR) increased after clamping and gradually declined after unclamping. The animals of C150 group suffered highest BP and HR, respiratory index, pulmonary dynamic compliance and cardiac output. Platelet count showed no significant changes between the C90 and C120 groups, whereas a decline was noticed in the C150 group. Pulmonary vascular resistance increased significantly after pulmonary hilum clamping; when unclamped, there were minor changes in animals of C90 and C120 groups while there was a persistent elevation in the C150 group. An elevated D-dimer was detected in the C150 group, whereas it was normal in the C90 and C120 groups. There was significantly serious inflammatory cell infiltration, perivascular oedema and haemorrhagic infiltration in the C150 group compared with the C90 and C120 groups.

CONCLUSIONS

We established a pulmonary hilum clamping animal model for investigating pulmonary damage. By studying the haemodynamic and lung function changes of three different unilateral pulmonary hilum clamping time, it was determined that 120min was the longest safety time for hilum clamping without lethal pulmonary injury in porcine models.

Cardiac Rupture due to Fall: A Case Study

Studies have shown that cardiac ruptures due to blunt trauma are seen more often than expected. However, epicardial injuries and atrial ruptures are common findings in deaths due to falls. Our aim is to present a unique, isolated cardiac rupture in a 2 year-old child resulting from a fall from a bed, to evaluate autopsy findings among the literature from a medico-legal point of view. Key words: Autopsy, Childhood, Fall

Survival following resuscitative thoracotomy for combined left ventricle and left atrium ruptures secondary to blunt trauma

Improvements in pre-hospital care and the development of integrated Trauma Systems have streamlined access for the severely injured to sophisticated, specialist Trauma Centre reception and resuscitation. We describe the initial care of a survivor of combined ruptures of the left ventricle and left atrium secondary to blunt injury. This case emphasises the contribution of such a Trauma System in achieving a favourable outcome for a severely injured trauma patient with injuries previously considered non-survivable.

Pulmonary trauma

Pulmonary trauma is common and devastating and is associated with significant morbidity and mortality. The present review highlights recent literature and case reports in this area. Topics of particular significance or interest include mechanisms of injury, potentially fatal intrathoracic vascular injuries, anesthetic management, fluid management (crystalloids as well as hemoglobin-based oxygen-carrying solutions), pain management of severe chest trauma, surgical management, and novel methods of diagnosis.

[Chest injury. Part II: Management of specific injuries]

Significant injuries to the thorax comprise pneumothorax, rib fractures, lung contusion, cardiac contusion, aortic laceration, ruptured diaphragm, and the very rare injuries to the tracheo-bronchial tree and the esophagus. A surgeon dealing with chest trauma patients needs to be familiar with the indications for and execution of chest tube insertion for thoracic drainage, pericardial puncture, and thoracoscopy and thoracotomy. Interventional techniques are gaining increasing acceptance in the management of major vascular injuries. The vast majority of patients with chest injury do not need an operative intervention, but it is necessary to place a thoracic drain in 10-15% of cases or to perform in a much lower proportion a pericardial puncture or a thoracotomy.

[Emergency surgery for chest injuries in the multiply injured: a systematic review]

OBJECTIVE

Severe chest injuries are still associated with significant morbidity and mortality. This systematic review assesses the early operative management of severe chest trauma in multi injured patients with special regard to the priority of the operative therapy.

METHODS

Clinical trials were systematically sought and collected (MEDLINE, Cochrane and hand searches). Of 618 abstracts, 46 articles were selected for detailed appraisal and were classified into evidence levels (1 to 5 according to the Oxford system).

RESULTS

Penetrating chest injuries in haemodynamically instable patients require emergency operative therapy. A thoracotomy is also indicated in excessive chest tube output (>1500 ml). An aortic rupture can be treated either by open suture or-in borderline patients-by endovascular stenting. In selected haemodynamically stable patients delayed treatment is also possible. Lesions of the tracheobronchial system should be treated urgently with primary surgical repair. Diaphragmatic ruptures should be closed urgently. Surgical stabilisation of rib fractures with an associated flail chest reduces the ventilator days and the length of intensive care unit stay.

CONCLUSION

A large part of early surgery for chest injuries is justified because it averts immediate threats to life (level 1c evidence). No randomised and only a few controlled trials have examined the relative value of the different surgical options so far. Long-term data are lacking especially on the safety of endovascular stenting.

Subtle abdominal aortic injury after blunt chest trauma

This case report describes a patient with an intimal flap of the abdominal aorta after a motor vehicle crash. The patient was an unrestrained driver with minimal anterior chest wall pain. This is a rare injury and one that is difficult to find due to its rarity. The lower cut of the chest CT scan found the injury. Its treatment with endovascular stenting is discussed.

Timing of endovascular repair of blunt traumatic thoracic aortic transections

BACKGROUND

Patients with blunt traumatic thoracic aortic transection (BTTAT) just distal to the takeoff of the left subclavian artery typically have concomitant injuries that make open emergent surgical repair highly risky. Over the past decade, endovascular repair of the injured thoracic aorta with commercially available and custom-made covered stents has developed as a viable option, with reported decreases in short-term morbidity and mortality. If active extravasation of contrast from the injured thoracic aorta is not appreciated on chest computed tomography scan, other concurrent injuries of the head, abdomen, and extremities can often be repaired with careful control of blood pressure. The timing of endovascular repair of the traumatic thoracic aortic transection, however, often comes into question, particularly with the presence of fever, pneumonia, or bacteremia. We sought to identify a time frame during which endovascular repair of BTTAT could safely be performed.

METHODS

Age, concomitant injuries, time from trauma to repair, type of device, and major outcomes were recorded.

RESULTS

Over a 5-year period (January 2000 to March 2005), 51 patients presented with BTTAT. Twenty-seven (52.9%) patients with BTTAT died shortly after arrival. Of the remaining 24, 9 underwent emergent open repair, with 1 intraoperative death. Two delayed open repairs were performed. Thirteen patients with BTTAT underwent delayed endovascular repair. Successful endovascular repair of BTTAT was performed in all 13 patients, with no intraoperative deaths. Seven patients were treated with commercial devices and six with custom-made covered stents. None of the repairs was performed emergently. The timing of repair ranged from 1 day to 7 months (median, 6 days), and all patients were treated aggressively with beta-blockade before surgery. One patient was discharged from the hospital and underwent elective repair at a later date. Three patients died in the postoperative period (30 days): two from multisystem organ failure and one from iliac artery complications encountered at the time of device deployment. The remaining 10 patients were successfully discharged to a rehabilitation facility.

CONCLUSIONS

The opportunity to successfully perform endovascular repair of BTTAT may be possible many days after the initial injury in the hemodynamically stable trauma patient.

Old fashion clinical judgment in the era of protocols: is mandatory chest X-ray necessary in injured patients?

BACKGROUND

The ATLS Course advocates that injured patients have a chest x-ray (CXR) to identify potential injuries. The purpose of this study was to correlate clinical indications and clinician judgment with CXR results to ascertain if a selective policy would be beneficial.

METHODS

Patients treated at a Level I trauma center over 12 months were prospectively evaluated. Before obtaining a CXR, signs, symptoms, and history suggestive of thoracic injury were identified. Additionally, a trauma surgeon (TS) recorded whether in their judgment a CXR was clinically indicated. These findings were compared with final CXR diagnoses. The sensitivity of individual clinical indicators, combinations of clinical indicators, and TS judgment for CXR abnormalities were calculated with a 95% confidence interval.

RESULTS

During the twelve-month study period, data were acquired on 772 patients (age 0-102 years). Seventy percent were male and 86.0% were injured by blunt force. Only 29% (N = 222) of the patients manifested one or more of the clinical indicators (signs and symptoms). The negative predictive value for the TS judgment was 98.2% which was superior to the clinical indicators. Reliance on the opinion of the TS to determine the need for a CXR would have eliminated 49.9% of CXRs and avoided hospital and radiologist reading charges totaling $100,078.22.

CONCLUSION

Mandatory CXR for all trauma patients has a low yield for abnormal findings. A selective policy relying on surgical judgment guided by clinical indicators is safe and efficacious while reducing cost and conserving resources.

Acute subclavian artery occlusion by blunt trauma: a case report

We report a case of acute left subclavian artery occlusion after blunt trauma, presenting with symptoms of acute left upper arm ischemia. Angiography was performed to confirm the injury. The injured left subclavian artery was approached via left thoracotomy, and an interposition graft was placed. The patient recovered without any complications.

Definitive management of acute cardiac tamponade secondary to blunt trauma

Blunt cardiac injuries are a leading cause of fatalities following motor-vehicle accidents. Injury to the heart is involved in 20% of road traffic deaths. Structural cardiac injuries (i.e. chamber rupture or perforation) carry a high mortality rate and patients rarely survive long enough to reach hospital. Chamber rupture is present at autopsy in 36-65% of death from blunt cardiac trauma, whereas in clinical series it is present in 0.3-0.9% of cases and is an uncommon clinical finding. Patients with large ruptures or perforations usually die at the scene or in transit--the rupture of a cardiac cavity, coronary artery or intrapericardial portion of a major vein or artery is usually instantly fatal because of acute tamponade. The small, rare, remaining group of patients who survive to hospital presentation usually have tears in a cavity under low pressure and prompt diagnosis and surgery can now lead to a survival rate of 70-80% in experienced trauma centres. As regional trauma systems evolve, patients with severe, but potentially survivable cardiac injury are surviving to ED. Two distinct syndromes are apparent--haemorrhagic shock and cardiac tamponade. Any patient with severe chest trauma, hypotension disproportionate to estimated loss of blood or with an inadequate response to fluid administration should be suspected of having a cardiac cause of shock. For patients with severe hypotension or in extremis, the treatment of choice is resuscitative thoracotomy with pericardotomy. Closed chest cardiopulmonary resuscitation is ineffective in these circumstances. Blunt traumatic cardiac injury presenting with shock is associated with a poor prognosis. The majority of survivors of blunt or penetrating cardiac injury present to the ED/trauma centre with vital signs. The main pathophysiologic determinant for most survivors is acute pericardial tamponade. The presence of normal clinical signs or normal ECG studies does not exclude tamponade. In recent years the widespread availability and use of ultrasound for the initial assessment of severely injured patients has facilitated the early diagnosis of cardiac tamponade and associated cardiac injuries. Two cases of survival from blunt traumatic cardiac trauma are described in the present paper to demonstrate survivability in the context of rapid assessment and intervention.

Damage control surgery for thoracic injuries

Damage control of thoracic injuries begins frequently with an emergency department thoracotomy via an anterolateral incision. Bleeding and air leaks are quickly temporised. As opposed to abdominal damage control where most injuries can be temporised, most thoracic injuries require initial definitive repair. Thus, the goal of thoracic damage control is to perform the least definitive repair using the fastest and easiest techniques to shorten the operative time as much as possible. There are some injuries that can be temporised and require re-operation once physiologic normality has been achieved.

Video-assisted thoracic surgery: state of the art in trauma care

The majority of chest-injured patients are managed with resuscitation and placement of chest tubes. Further interventions are required for complications or missed injuries. Video-assisted thoracic surgery (VATS) has become standard in elective surgery. Our purpose was to review the use of VATS in trauma. The literature and our experience support the use of VATS for specific indications. These indications are: (1) management of retained haemothorax; (2) management of persistent pneumothorax; (3) evaluation of the diaphragm in penetrating thoraco-abdominal injuries and management; (4) management of infected pleural space collections; and (5) diagnosis and management of on-going bleeding in haemodynamically stable patients. VATS for specific indications in trauma is associated with improved outcomes and decreased length of stay. VATS provides diagnostic and therapeutic benefit and should be included in the trauma surgeon's clinical armamentarium.

Emergency thoracotomy and the military surgeon

Emergency thoracotomy might be necessary in battle surgery and might, in an era of superspecialization, be a challenge for the present day military surgeon. He or she might, nonetheless, be the only surgeon in the austere circumstances of a forward field surgical team. This paper provides assistance and guidelines for a military surgeon in such circumstances, including surgical indications and approaches, surgical procedures and techniques. It includes recent advances in this area and principles of 'damage control'.

Lesões traumáticas do mediastino: aspectos na tomografia computadorizada

As lesões traumáticas mediastinais constituem achados pouco freqüentes no trauma torácico, mas são de extrema importância, por representarem mau prognóstico, dada a sua gravidade e lesões associadas. O trauma mediastinal é cada vez mais diagnosticado pela tomografia computadorizada, em especial pelo rápido tempo de aquisição decorrente da técnica helicoidal, que permite a avaliação de pacientes em estado grave, possibilitando a adoção de conduta terapêutica eficiente. Os autores estudaram 11 pacientes com trauma torácico submetidos a tomografia computadorizada, os quais apresentaram lesões mediastinais. A hemorragia mediastinal representou a lesão mais comum nesta casuística, manifestando-se sob a forma de infiltração da gordura mediastinal, com a presença de material denso permeando os espaços mediastinais, ou sob a forma de hematoma. O hemopericárdio representou a segunda lesão mais comum, caracterizado por material denso ou líquido no interior do pericárdio. As lesões aórticas foram observadas em três casos, caracterizadas por irregularidade parietal no contorno aórtico ou por pseudo-aneurisma. Neste trabalho o trauma torácico fechado foi observado em seis casos, enquanto o trauma aberto ocorreu em cinco pacientes. As causas de trauma fechado foram atropelamento, colisão automobilística e queda de altura. A forma penetrante de traumatismo torácico decorreu de dois modos de agressão: lesão por arma de fogo e lesão por arma branca

Induced hypothermia in critical care medicine: a review

BACKGROUND

Clinical trials of induced hypothermia have suggested that this treatment may be beneficial in selected patients with neurologic injury.

OBJECTIVES

To review the topic of induced hypothermia as a treatment of patients with neurologic and other disorders.

DESIGN

Review article.

INTERVENTIONS

None.

MAIN RESULTS

Improved outcome was demonstrated in two prospective, randomized, controlled trials in which induced hypothermia (33 degrees C for 12-24 hrs) was used in patients with anoxic brain injury following resuscitation from prehospital cardiac arrest. In addition, prospective, randomized, controlled trials have been conducted in patients with severe head injury, with variable results. There also have been preliminary clinical studies of induced hypothermia in patients with severe stroke, newborn hypoxic-ischemic encephalopathy, neurologic infection, and hepatic encephalopathy, with promising results. Finally, animal models have suggested that hypothermia that is induced rapidly following traumatic cardiac arrest provides significant neurologic protection and improved survival.

CONCLUSIONS

Induced hypothermia has a role in selected patients in the intensive care unit. Critical care physicians should be familiar with the physiologic effects, current indications, techniques, and complications of induced hyperthermia.

Correlation of clinical characteristics and outcomes with injury scoring in blunt cardiac trauma

BACKGROUND

Clinical sequelae from blunt cardiac trauma (BCT) may range from minor electrocardiographic abnormalities to death from free-wall rupture. There are no established clinical characteristics or injury scoring systems that are able to predict survival in these patients.

METHODS

A retrospective review of medical records from a Level I trauma center identified 47 patients with BCT. A grade assigned on the basis of the American Association for the Surgery of Trauma Organ Injury Scale (OIS) was assigned to each case studied. Clinical data, including the Injury Severity Score (ISS), and outcomes were analyzed for association with OIS grade.

RESULTS

The average ISS was 27.9, and the overall mortality rate was 31.9%. The majority of patients were either grade II or IV, with the latter having the highest mortality. Hypotension at admission, cardiac arrest, lack of vital signs at admission, ISS, hours to diagnosis, and death all had significant association with assigned OIS grade. Factors associated with mortality included ISS; OIS grade; shorter time to diagnosis; cardiac tamponade; cardiac rupture; lack of vital signs at admission; and concomitant injury to either the thoracic aorta or to the liver, spleen, or kidneys.

CONCLUSION

The OIS grade, assigned on the basis of anatomic site of injury and electrocardiographic abnormalities, appears to correlate with severity of injury and survival. Although injury scoring should not be used exclusively to guide management in trauma patients, the grading system studied may be useful in predicting outcomes in patients with BCT.

Venilator Management and Criical Care Issues Following Cardiothoracic Trauma

Traumatic injury of the cardiac, pulmonary, or vascular systemsmay result in severe critical illness. Not only does the injury itself result in compromise of normal physiology, but initiation of the inflammatory cascade and mismanagement of the ventilator may lead to worsening status, the acute respiratory distress syndrome, and multiple organ dysfunction. Traumatic injury places the patient athigh risk of infection and nutritional compromise. We review basic concepts of mechanical ventilation and ventilator -associated or -induced lung injury. Barotrauma, volutrauma, atelectrauma and biotrauma, and methods for the clinician to prevent them, arediscussed. Airway pressure release ventilation, mandatory minute ventilation and adaptive support ventilation techniques are intro-duced, as is a discussion of the importance of spontaneous breathing during mechanical ventilation. Special attention is paid to a comprehensive approach to respiratory care. Unique modalities such as prone positioning, independent lung ventilation, and extracorporeal support are presented. The importance of adapting the mode or the minimal-injury concepts of mechanical ventilation to specific injuries is presented. Management approaches to these injuries, including ventilator therapy, pain control, surgical techniques, and critical care issues are described. An overview of the issues of infection inherent to trauma, and nutritional matters, including enteral versus parenteral therapy is presented. Immune-enhanced diets and antioxidantdrugs are integral components of the comprehensive approach to the trauma patient suffering critical illness, and pertinent literatureis summarized.

Natural history of traumatic rupture of the thoracic aorta managed nonoperatively: a longitudinal analysis

BACKGROUND

Although traumatic rupture of the thoracic aorta (TRA) has traditionally been considered a surgical emergency, there exists a small patient population for whom nonoperative management may be appropriate. The short- and long-term consequences of patients managed in a nonoperative fashion remain unclear.

METHODS

A review of patients admitted with TRA over a period of 16 years was performed. Patients who did not undergo operative repair within 24 hours of injury and diagnosis comprised the study group.

RESULTS

One hundred forty-five patients were admitted with TRA. Of these, 30 underwent a period of nonoperative management. The mean age of the study patients was 44 +/- 21 years, 80% were male, and the mean Injury Severity Score (ISS) was 34 +/- 9. Fifteen patients underwent delayed operation (DELAY group) at more than 24 hours after injury and diagnosis and 15 patients never underwent repair (NON-OP group). The median time to operation in the DELAY group was 3 days (range 2 to 90). Three patients exhibited progression of TRA within 5 days of injury and of these, 2 died. A total of 3 deaths occurred in the DELAY group (1 rupture and 2 intraoperative arrests). The fifteen NON-OP patients were significantly older (mean age 52 +/- 22 versus 36 +/- 18 years; p = 0.03), tended to be more severely injured (mean ISS 36 +/- 9 versus 32 +/- 8; p = 0.2), and had more premorbid risk factors than the DELAY patients. Five NON-OP patients died, all because of severe head injuries. On long-term follow-up of NON-OP patients, all 10 survivors are alive at a median of 2.5 years (range 6 months to 5 years) without progression of injury or the need for operation. Five of the 10 had complete radiographic resolution of their injuries and 5 have asymptomatic and radiographically stable pseudoaneurysms.

CONCLUSIONS

Selected patients with multiple severe associated injuries or high-risk premorbid conditions may have their operations for TRA delayed temporarily or even indefinitely with acceptable survival rates. The potential for rapid progression of TRA in the same patients, however, mandates serial radiographic examinations during the first week of hospitalization after injury and diagnosis.

The Usefulness of Serum Troponin Levels in Evaluating Cardiac Injury

The diagnosis and clinical significance of blunt cardiac injury remains controversial. Cardiac troponin I is not found in skeletal muscle and has a high sensitivity for myocardial ischemia or injury. We hypothesized that normal troponin levels 4 to 6 hours postinjury would effectively exclude the diagnosis of cardiac contusion. A prospective evaluation of all blunt trauma patients older than 16 and admitted with the possible diagnosis of blunt cardiac injury was undertaken. Patients in whom this diagnosis was considered had an electrocardiogram (EKG) on admission, serum troponin, CPK and isoenzymes 4 to 6 hours postinjury, and admission with overnight telemetry. Other laboratory data and radiographic imaging was obtained as indicated. Seventy-two patients met criteria for entry into the study. Data was incomplete or inaccurately obtained on six patients, and they were excluded. Forty patients had normal troponins and normal EKG's on admission and were discharged the following day without any untoward effect. Sixteen patients were admitted with abnormal EKGs. All of these 16 patients had normal troponins 4 to 6 hours after their injury. They all did well and were discharged the following day. Ten patients had elevated troponins 4 to 6 hours after injury. One died two days later from refractory cardiogenic shock. Another was noted to have severely depressed left ventricular function by echocardiography. The other eight patients sustained no cardiac sequelae and were discharged once recovered from injuries. In the hemodynamically stable patient a normal troponin 4 to 6 hours after injury excludes clinically significant blunt cardiac injury. This holds true whether the admission EKG is normal or not. An elevated troponin does not definitively diagnose a clinically significant contusion. However, these patients should be monitored at least for 24 hours. Patients suspicious for cardiac contusions who have normal troponins and no other serious injuries may be safely discharged to go home from the emergency department.