Blaine L. Enderson

Prospective Study of Blunt Aortic Injury: Multicenter Trial of the American Association for the Surgery of Trauma

BACKGROUND Blunt aortic injury is a major cause of death from blunt trauma. Evolution of diagnostic techniques and methods of operative repair have altered the management and posed new questions in recent years. METHODS This study was a prospectively conducted multi-center trial involving 50 trauma centers in North America under the direction of the Multi-institutional Trial Committee of the American Association for the Surgery of Trauma. RESULTS There were 274 blunt aortic injury cases studied over 2.5 years, of which 81% were caused by automobile crashes. Chest computed tomography and transesophageal echocardiography were applied in 88 and 30 cases, respectively, and were 75 and 80% diagnostic, respectively. Two hundred seven stable patients underwent planned thoracotomy and repair. Clamp and sew technique was used in 73 (35%) and bypass techniques in 134 (65%). Overall mortality was 31%, with 63% of deaths being attributable to aortic rupture; mortality was not affected by method of repair. Paraplegia occurred postoperatively in 8.7%. Logistic regression analysis demonstrated clamp and sew (p = 0.002) and aortic cross clamp time of > or = 30 minutes (p = 0.01) to be associated with development of postoperative paraplegia. CONCLUSIONS Rupture after hospital admission remains a major problem. Although newer diagnostic techniques are being applied, at this time aortography remains the diagnostic standard. Aortic cross clamp time beyond 30 minutes was associated with paraplegia; bypass techniques, which provide distal aortic perfusion, produced significantly lower paraplegia rates than the clamp and sew approach.

Blunt splenic injury in adults: Multi-institutional study of the Eastern Association for the Surgery of Trauma

BACKGROUND Nonoperative management of blunt injury to the spleen in adults has been applied with increasing frequency. However, the criteria for nonoperative management are controversial. The purpose of this multi-institutional study was to determine which factors predict successful observation of blunt splenic injury in adults. METHODS A total of 1,488 adults (>15 years of age) with blunt splenic injury from 27 trauma centers in 1997 were studied through the Multi-institutional Trials Committee of the Eastern Association for the Surgery of Trauma. Statistical analysis was performed with analysis of variance and extended chi2 test. Data are expressed as mean +/- SD; a value of p < 0.05 was considered significant. RESULTS A total of 38.5 % of patients went directly to the operating room (group I); 61.5% of patients were admitted with planned nonoperative management. Of the patients admitted with planned observation, 10.8% failed and required laparotomy; 82.1% of patients with an Injury Severity Score (ISS) < 15 and 46.6% of patients with ISS > 15 were successfully observed. Frequency of immediate operation correlated with American Association for the Surgery of Trauma (AAST) grades of splenic injury: I (23.9%), II (22.4%), III (38.1%), IV (73.7%), and V (94.9%) (p < 0.05). Of patients initially managed nonoperatively, the failure rate increased significantly by AAST grade of splenic injury: I (4.8%), II (9.5%), III (19.6%), IV (33.3%), and V (75.0%) (p < 0.05). A total of 60.9% of the patients failed nonoperative management within 24 hours of admission; 8% failed 9 days or later after injury. Laparotomy was ultimately performed in 19.9% of patients with small hemoperitoneum, 49.4% of patients with moderate hemoperitoneum, and 72.6% of patients with large hemoperitoneum. CONCLUSION In this multicenter study, 38.5% of adults with blunt splenic injury went directly to laparotomy. Ultimately, 54.8% of patients were successfully managed nonoperatively; the failure rate of planned observation was 10.8%, with 60.9% of failures occurring in the first 24 hours. Successful nonoperative management was associated with higher blood pressure and hematocrit, and less severe injury based on ISS, Glasgow Coma Scale, grade of splenic injury, and quantity of hemoperitoneum.

The Tertiary Trauma Survey: A Prospective Study of Missed Injury

The Advanced Trauma Life Support Course defines a primary and a secondary survey to rapidly identify life-threatening and associated injuries, respectively, in multiple trauma patients. However, circumstances during resuscitation, including multiple casualties, emergent operation, unconsciousness, etc., may interfere with this process. An initial review of our trauma registry data yielded a modest 2% incidence of missed injuries in a 90% blunt trauma population. In order to determine the true incidence of missed injuries, a tertiary survey was performed prospectively on all injured patients (N = 399) admitted during a recent 3-month period. After completion of the primary and secondary surveys (including appropriate roentgenographs), all injuries were listed in the trauma admission record. Patients were later reexamined immediately before ambulation or, in head-injured patients, upon regaining consciousness. All missed injuries were documented, including site and type of injury, reason missed, how identified, and attendant morbidity. Forty-one missed injuries were found in 36 patients (9%). These included: 21 extremity fractures, five spinal fractures, two facial fractures, five thoracic injuries, six abdominal injuries (including five splenic lacerations), and two vascular injuries. The most common reason for injuries to be missed was altered level of consciousness due to head injury or alcohol. Other reasons included severity of injury and instability requiring immediate operation, lack of symptoms at admission, technical problems, and low index of suspicion by the examiner. None of the missed injuries resulted in death. However, one missed injury caused serious disability and seven required operative correction.(ABSTRACT TRUNCATED AT 250 WORDS)

Tube thoracostomy for occult pneumothorax: a prospective randomized study of its use.

Occult pneumothorax is defined as a pneumothorax that is detected by abdominal computed tomographic (CT) scanning, but not routine supine screening chest roentgenograms. Forty trauma patients with occult pneumothorax were prospectively randomized to management with tube thoracostomy (n = 19) or observation (n = 21) without regard to the possible need for positive pressure ventilation, to test the hypothesis that tube thoracostomy is unnecessary in this entity. Eight of the 21 patients observed had progression of their pneumothoraces on positive pressure ventilation, with three developing tension pneumothorax. None of the patients with tube thoracostomy suffered major complications as a result of the procedure. Hospital and ICU lengths of stay were not increased by tube thoracostomy. Patients with occult pneumothorax who require positive pressure ventilation should undergo tube thoracostomy.

Early evaluation of acute traumatic coagulopathy by thrombelastography

Posttraumatic coagulopathy is a major cause of morbidity. This prospective study evaluated the thrombelastography (TEG) system and PlateletMapping (Haemoscope Corporation, Niles, Ill) values posttrauma, and it correlated those values with transfusions and fatalities. After institutional review board approval, assays were performed on 161 trauma patients. One citrated blood sample was collected onsite (OS), and 1 citrate and 1 heparinized sample were collected within 1 h of arrival to the emergency department (ED). Paired and unpaired t-testing was performed for nominal data with chi square testing for categorical values. Except for a slight increase in clot strength (maximal amplitude (MA)), there were no significant changes from OS to the ED. None of the TEG parameters were significantly different for the 22 patients who required transfusion. PlateletMapping showed lower platelet adenosine diphosphate (ADP) responsiveness in patients who needed transfusions (MA = 22.7 +/- 17.1 vs MA = 35.7 +/- 19.3, P = 0.004) and a correlation of fibrinogen <100 mg/dL with fatalities (P = 0.013). For the 14 fatalities, TEG reaction (R) time was 3703 +/- 11,618 versus 270 +/- 393 s (P = < 0.001), and MA was 46.4 +/- 22.4 versus 64.7 +/- 9.8 mm (P < 0.001). Hyperfibrinolysis (percent fibrinolysis after 60 min (LY60) >15%) was observed in 3 patients in the ED with a 67% fatality rate (P = < 0.001 by chi-square testing). PlateletMapping assays correlated with the need for blood transfusion. The abnormal TEG System parameters correlated with fatality. These coagulopathies were already evident OS. The TEG assays can assess coagulopathy, platelet dysfunction, and hyperfibrinolysis at an early stage posttrauma and suggest more effective interventions.

On-scene helicopter transport of patients with multiple injuries--comparison of a German and an American system.

Hospital-based helicopter services from a German (GER) and an American (AMR) university-affiliated trauma center were reviewed. All patients with multiple injuries transported via helicopter from the scene to the trauma centers during a 1-year period were included. The patients were comparable regarding mechanism of injury, age, flight times, mean ISS, ISS distribution, and number of severe injuries per body region (patients with AIS score > 3 for head, thorax, and abdomen). Overall mortality was 21 of 221 (9.5%) for GER and 21 of 186 (11.3%) for AMR (NS). Survivor-based TRISS analysis yielded Z statistics of +2.459 for GER (p < 0.025) and +1.049 for AMR (NS). M statistics were 0.89 for GER, 0.874 for AMR; the W statistic +1.35 for GER. There were nine unexpected survivors (Ps < 0.50) for GER and six for AMR. There was a significantly higher (p < 0.01) number of early deaths (< 6 hours) in AMR (12; ISS = 56) than in GER (four; ISS = 64). Analysis of the prehospital data demonstrated significant differences in the mean volume of IV fluids infused: 1800 mL, GER; 825 mL, AMR (p < 0.05); rate of intubation: 82 of 221 (37.1%) GER; 24 of 186 (13.4%) AMR (p < 0.001); and thoracic decompressions: 20 of 221 (9.1%) GER; 1 of 186 (0.5%) AMR (p < 0.001). Prehospital care in the GER system is directed on scene by a trauma surgeon member of the flight crew compared with a nurse/paramedic team with remote medical control in the AMR system.(ABSTRACT TRUNCATED AT 250 WORDS)

Penetrating esophageal injuries: Multicenter study of the American Association for the Surgery of Trauma

OBJECTIVE The purpose of this study was to define the period of time after which delays in management incurred by investigations cause increased morbidity and mortality. The outcome study is intended to correlate time with death from esophageal causes, overall complications, esophageal related complications, and surgical intensive care unit length of stay. METHODS This was a retrospective multicenter study involving 34 trauma centers in the United States, under the auspices of the American Association for the Surgery of Trauma Multi-institutional Trials Committee over a span of 10.5 years. Patients surviving to reach the operating room (OR) were divided into two groups: those that underwent diagnostic studies to identify their injuries (preoperative evaluation group) and those that went immediately to the OR (no preoperative evaluation group). Statistical methods included Fishers exact test, Students T test, and logistic regression analysis. RESULTS The study involved 405 patients: 355 male patients (86.5%) and 50 female patients (13.5%). The mean Revised Trauma Score was 6.3, the mean Injury Severity Score was 28, and the mean time interval to the OR was 6.5 hours. There were associated injuries in 356 patients (88%), and an overall complication rate of 53.5%. Overall mortality was 78 of 405 (19%). Three hundred forty-six patients survived to reach the OR: 171 in the preoperative evaluation group and 175 in the no preoperative evaluation group. No statistically significant differences were noted in the two groups in the following parameters: number of patients, age, Injury Severity Score, admission blood pressure, anatomic location of injury (cervical or thoracic), surgical management (primary repair, resection and anastomosis, resection and diversion, flaps), number of associated injuries, and mortality. Average length of time to the OR was 13 hours in the preoperative evaluation group versus 1 hour in the no preoperative evaluation group (p < 0.001). Overall complications occurred in 134 in the preoperative evaluation group versus 87 in the no preoperative evaluation group (p < 0.001), and 74 (41%) esophageal related complications occurred in the preoperative evaluation group versus 32 (19%) in the no preoperative evaluation group (p = 0.003). Mean surgical intensive care unit length of stay was 11 days in the preoperative evaluation group versus 7 days in the no preoperative evaluation group (p = 0.012). Logistic regression analysis identified as independent risk factors for the development of esophageal related complications included time delays in preoperative evaluation (odds ratio, 3.13), American Association for the Surgery of Trauma Organ Injury Scale grade >2 (odds ratio, 2.62), and resection and diversion (odds ratio, 4.47). CONCLUSION Esophageal injuries carry a high morbidity and mortality. Increased esophageal related morbidity occurs with the diagnostic workup and its inherent delay in operative repair of these injuries. For centers practicing selective management of penetrating neck injuries and transmediastinal gunshot wounds, rapid diagnosis and definitive repair should be made a high priority.

Missed Injuries: The Trauma Surgeon’s Nemesis

The multiply injured trauma patient presents a diagnostic and therapeutic challenge: that of discovering all injuries while simultaneously proceeding with resuscitation and maintaining life. Many factors involved in the initial resuscitation of the multiply injured patient, such as altered level of consciousness, hemodynamic instability, or inexperience and diagnostic oversight, may lead to missed injuries. Injuries may be missed at any stage of the management of the trauma patient, including intraoperatively, and may involve all regions of the body. Established protocols in the initial management of the multiply injured patient, such as the primary and secondary surveys of the Advanced Trauma Life Support Course, will minimize the chance of missing immediately life-threatening injuries in the emergency department. A careful intraoperative approach must be used in all patients, but especially in those with hemodynamic instability, so that all areas are examined for possible injury, rather than concentrating simply on what is known to be injured. Use of the tertiary survey, a careful re-examination of the multiply injured trauma patient, especially when he or she awakes, will help detect injuries missed during the initial evaluation. Injuries will be missed. Rather than dismissing these as occurrences that happen only to the inexperienced or incompetent, one should approach the multiply injured trauma patient with both special alertness and the humility necessary to search for diagnostic oversights. This approach will lead to early discovery of missed injuries and will minimize the consequences.

Acute injuries of the trachea and major bronchi: importance of early diagnosis

BACKGROUND Tracheobronchial injuries are encountered with increasing frequency because of improvements in prehospital care and early initiation of the Advanced Trauma Life Support protocol. We review our experience with these injuries with the hypothesis that the leading determinant of patient outcome is the time interval to diagnosis. METHODS Patients with tracheobronchial injury were identified from the registry of our level 1 trauma center during a 10-year period ending December 1997. Clinical presentation, diagnostic evaluation, surgical management, and outcome were reviewed. RESULTS Twenty patients with ten cervical tracheal injuries and ten intrathoracic tracheobronchial injuries were treated. The mechanism of injury involved blunt trauma in 11 and penetrating trauma in 9. All patients underwent surgical debridement and primary repair. Patients with isolated airway injuries were discharged home after a mean hospital stay of 6 days and had no early complications. Three patients had delayed diagnosis (> 24 hours), and all sustained complications including death (1 patient) and multiorgan system failure (2 patients). The overall mortality rate was 15%. CONCLUSIONS Operative management of tracheobronchial injuries can be achieved with acceptable mortality. Independent of mechanism or anatomic location of injury, delay in diagnosis is the single most important factor influencing outcome. Early recognition of tracheobronchial injury and expedient institution of appropriate surgical intervention are essential in these potentially lethal injuries.

Outcome of the current management of splenic injuries.

BACKGROUND For patients > 55 years, nonoperative management (NOM) of blunt splenic injury remains controversial. Conflicting reports of excessively high or acceptably low failure rates have discouraged widespread application of NOM in these older patients. However, the small number of patients in these studies limits the impact of their conclusions. METHODS We manage splenic injury nonoperatively in all appropriate patients without regard to age. We present the largest series of patients > 55 years who have been managed nonsurgically, in a retrospective review of all patients with blunt splenic injury admitted to our trauma center between 1996 and 1999. RESULTS In 4 years, 542 patients were admitted with blunt splenic injury. Eighty-three patients were > 55 years, and 61 of these patients underwent NOM. Seven older patients failed NOM and required delayed splenectomy, yielding a failure rate of 11.4%. This failure rate was statistically equivalent to the 7% failure rate of patients < 55 years. This study has a power of 80% to detect a failure rate change from 7% to 20%. By multivariate analysis, the only factor that significantly increased the risk of NOM failure was splenic injury grade. Patients > 55 years had a higher mortality than younger patients regardless of NOM/operative treatment. Splenic injury did not directly cause any of the deaths in patients > 55 years who had NOM or failure of NOM. High-grade splenic injuries fail NOM in those > 55 years. CONCLUSION Nonoperative management of lower grade splenic injuries in patients > 55 years can be accomplished with an acceptably low failure rate. Only grade of splenic injury, not patient age, increases the risk of NOM failure.