Daniel R. Margulies

Operative repair or endovascular stent graft in blunt traumatic thoracic aortic injuries: results of an American Association for the Surgery of Trauma Multicenter Study.

INTRODUCTION The purpose of this American Association for the Surgery of Trauma multicenter study is to assess the early efficacy and safety of endovascular stent grafts (SGs) in traumatic thoracic aortic injuries and compare outcomes with the standard operative repair (OR). PATIENTS Prospective, multicenter study. Data for the following were collected: age, blood pressure, and Glasgow Coma Scale (GCS) at admission, type of aortic injury, injury severity score, abbreviate injury scale (AIS), transfusions, survival, ventilator days, complications, and intensive care unit and hospital days. The outcomes between the two groups (open repair or SG) were compared, adjusting for presence of critical extrathoracic trauma (head, abdomen, or extremity AIS >3), GCS score </=8, systolic blood pressure <90 mm Hg, and age >55 years. Separate multivariable analysis was performed, one for patients without and one for patients with associated critical extrathoracic injuries (head, abdomen, or extremity AIS >3), to compare the outcomes of the two therapeutic modalities adjusting for hypotension, GCS score </=8, and age >55 years. RESULTS One hundred ninety-three patients met the criteria for inclusion. Overall, 125 patients (64.9%) were selected for SG and 68 (35.2%) for OR. SG was selected in 71.6% of the 74 patients with major extrathoracic injuries and in 60.0% of the 115 patients with no major extrathoracic injuries. SG patients were significantly older than OR patients. Overall, 25 patients in the SG group (20.0%) developed 32 device-related complications. There were 18 endoleaks (14.4%), 6 of which needed open repair. Procedure-related paraplegia developed in 2.9% in the OR and 0.8% in the SG groups (p = 0.28). Multivariable analysis adjusting for severe extrathoracic injuries, hypotension, GCS, and age, showed that the SG group had a significantly lower mortality (adjusted odds ratio: 8.42; 95% CI: [2.76-25.69]; adjusted p value <0.001), and fewer blood transfusions (adjusted mean difference: 4.98; 95% CI: [0.14-9.82]; adjusted p value = 0.046) than the OR group. Among the 115 patients without major extrathoracic injuries, higher mortality and higher transfusion requirements were also found in the OR group (adjusted odds ratio for mortality: 13.08; 95% CI [2.53-67.53], adjusted p value = 0.002 and adjusted mean difference in transfusion units: 4.45; 95% CI [1.39-7.51]; adjusted p value = 0.004). Among the 74 patients with major extrathoracic injuries, significantly higher mortality and pneumonia rate were found in the OR group (adjusted p values 0.04 and 0.03, respectively). Multivariate analysis showed that centers with high volume of endovascular procedures had significantly fewer systemic complications (adjusted p value 0.001), fewer local complications (adjusted p value p = 0.033), and shorter hospital lengths of stay (adjusted p value 0.005) than low-volume centers. CONCLUSIONS Most surgeons select SG for traumatic thoracic aortic ruptures, irrespective of associated injuries, injury severity, and age. SG is associated with significantly lower mortality and fewer blood transfusions, but there is a considerable risk of serious device-related complications. There is a major and urgent need for improvement of the available endovascular devices.

Diagnosis and treatment of blunt thoracic aortic injuries: changing perspectives.

BACKGROUND The diagnosis and management of blunt thoracic aortic injuries has undergone many significant changes over the last decade. The present study compares clinical practices and results between an earlier prospective multicenter study by the American Association for the Surgery of Trauma completed in 1997 (AAST1) and a new similar study completed in 2007 (AAST2). METHODS The AAST1 study included 274 patients from 50 participating centers over a period of 30 months. The AAST2 study included 193 patients from 18 centers, over a period of 26 months. The comparisons between the two studies included the method of definitive diagnosis of the aortic injury [computed tomography (CT) scan, aortography, transesophageal echocardiogram (TEE) or magnetic resonance imaging], the method of definitive aortic repair (open repair vs. endovascular repair, clamp and sew vs. bypass techniques), the time from injury to procedure (early vs. delayed repair), and outcomes (survival, procedure-related paraplegia, other complications). RESULTS There was a major shift of the method of definitive diagnosis of the aortic injury, from aortography in the AAST1 to CT scan in AAST2, and a nearly complete elimination of aortography and TEE in the AAST2 study. In the AAST2 study the diagnosis was made by CT scan in 93.3%, aortography in 8.3%, and TEE in 1.0% of patients when compared with 34.8%, 87.0%, and 11.9%, respectively, in the AAST1 study (p < 0.001). The mean time from injury to aortic repair increased from 16.5 hours in the AAST1 study to 54.6 hours in the AAST2 study (p < 0.001). In the AAST1 study, all patients were managed with open repair, whereas in the AAST2 study only 35.2% were managed with open repair and the remaining 64.8% were managed with endovascular stent-grafts. In the patients managed with open repair, the use of bypass techniques increased from 64.7% to 83.8%. The overall mortality, excluding patients in extremis, decreased significantly from 22.0% to 13.0% (p = 0.02). Also, the incidence of procedure-related paraplegia in patients with planned operation, decreased from 8.7% to 1.6% (p = 0.001). However, the incidence of early graft-related complications increased from 0.5% in the AAST1 to 18.4% in the AAST2 study. CONCLUSIONS Comparison between the two AAST studies in 1997 and 2007 showed a major shift in the diagnosis of the aortic injury, with the widespread use of CT scan and the almost complete elimination of aortography and TEE. The concept of delayed definitive repair has gained wide acceptance. Endovascular repair has replaced open repair to a great extent. These changes have resulted in a major reduction of mortality and procedure-related paraplegia but also a significant increase of early graft-related complications.

The effect of gender on patients with moderate to severe head injuries.

BACKGROUND Male and female nervous systems respond differently to traumatic brain injury (TBI) and in vivo research relates this difference to neuroprotection from female sex hormones. Attempts to replicate female sex hormone-related neuroprotection in clinical studies have been unsuccessful. The objective of this study was to determine whether gender or menopausal status affects mortality in patients with moderate to severe TBI. METHODS A retrospective review of all patients with isolated moderate to severe TBI was undertaken using data from the National Trauma Database version 6.2 (2000-2005). Isolated TBI was defined as head Abbreviated Injury Score >/=3 in patients without significant extracranial injuries (Abbreviated Injury Score <3 for other anatomic regions). Demographics, Injury Severity Score, and outcomes (mortality, intensive care unit and hospital length of stay, and complications) were compared. The population was stratified into age subgroups: 14 to 45 years (premenopausal), 46 to 55 years (perimenopausal), and older than 55 years (postmenopausal). Logistic regression analysis was used to determine the relationship among female gender, mortality, and development of complications after moderate to severe TBI. RESULTS A total of 72,294 patients with moderate to severe TBI were evaluated. Females showed a significantly lower risk in both mortality (adjusted odds ratios [AOR], 0.82; 95% confidence intervals [CI], 0.77-0.87; p < 0.0001) and in developing any type of complications (AOR, 0.88; 95% CI, 0.84-0.93; p < 0.0001) than the male population after adjusting for differences in patient characteristics. After age stratification, perimenopausal women (46-55 years) and postmenopausal women (older than 55 years) showed a significantly lower risk in mortality (AOR, 0.76; 95% CI, 0.63-0.92; p < 0.0044 and AOR, 0.79; 95% CI, 0.73-0.86; p < 0.0001, respectively). There was no difference in mortality in premenopausal women compared with their male age-matched counterparts (AOR, 1.09; 95% CI, 0.99-1.21; p = 0.0917). CONCLUSIONS Female gender is independently associated with reduced mortality and decreased complications after TBI. As peri- and postmenopausal women demonstrated improved survival, and premenopausal women did not, estrogen unlikely confers neuroprotection in women after TBI. Future TBI treatment may benefit with further research focused on why peri- and postmenopausal women show decreased mortality after TBI.

Role of Anemia in Traumatic Brain Injury

BACKGROUND Few studies have investigated the effects of anemia in patients with traumatic brain injury (TBI). The objective of this study was to examine the role of anemia and blood transfusion on outcomes in TBI patients. STUDY DESIGN We performed a retrospective review of all blunt trauma patients with TBI admitted to the ICU from July 1998 to December 2005. Admission and daily ICU blood hemoglobin (hemoglobin) levels and blood transfusions during the first week of hospitalization were measured. Anemia was defined as a hemoglobin<9 g/dL occurring on 3 consecutive blood draws. The role of anemia and blood transfusion was investigated using logistic regression adjusting for factors, with p<0.2 from the bivariate analysis. RESULTS During the study period, 1,150 TBI patients were admitted to the ICU. When both anemia and blood transfusion were included in the full model, blood transfusion was significantly associated with higher mortality (adjusted odds ratio [AOR], 2.19 [95% CI, 1.27, 3.75]; p=0.0044) and more complications (AOR, 3.67 [95% CI, 2.18, 6.17]; p<0.0001), but anemia was not. But when transfusion was not included in the full model, anemia was a significant risk factor for mortality (AOR, 1.59 (95% CI, 1.13, 2.24); p=0.007) and for complications (AOR, 1.95 [95% CI, 1.42, 2.70]; p<0.0001). CONCLUSIONS Blood transfusion is associated with significantly worse outcomes in traumatic brain injured patients. In addition, blood transfusion is a major contributing factor to worse outcomes in TBI patients who are anemic. We caution against the liberal use of blood in TBI patients.

Blunt Traumatic Thoracic Aortic Injuries: Early or Delayed Repair—results of an American Association for the Surgery of Trauma Prospective Study

BACKGROUND The traditional approach to stable blunt thoracic aortic injuries (TAI) is immediate repair, with delayed repair reserved for patients with major associated injuries. In recent years, there has been a trend toward delayed repair, even in low-risk patients. This study evaluates the current practices in the surgical community regarding the timing of aortic repair and its effects on outcomes. METHODS This was a prospective, observational multicenter study sponsored by the American Association for the Surgery of Trauma. The study included patients with blunt TAI scheduled for aortic repair by open or endovascular procedure. Patients in extremis and those managed without aortic repair were excluded. The data collection included demographics, initial clinical presentation, Injury Severity Scores, type and site of aortic injury, type of aortic repair (open or endovascular repair), and time from injury to aortic repair. The study patients were divided into an early repair (< or = 24 hours) and delayed repair groups (> 24 hours). The outcome variables included survival, ventilator days, intensive care unit (ICU) and hospital lengths of stay, blood transfusions, and complications. The outcomes in the two groups were compared with multivariate analysis after adjusting for age, Glasgow Coma Scale, hypotension, major associated injuries, and type of aortic repair. A second multivariate analysis compared outcomes between early and delayed repair, in patients with and patients without major associated injuries. RESULTS There were 178 patients with TAI eligible for inclusion and analysis, 109 (61.2%) of which underwent early repair and 69 (38.8%) delayed repair. The two groups had similar epidemiologic, injury severity, and type of repair characteristics. The adjusted mortality was significantly higher in the early repair group (adjusted OR [95% CI] 7.78 [1.69-35.70], adjusted p value = 0.008). The adjusted complication rate was similar in the two groups. However, delayed repair was associated with significantly longer ICU and hospital lengths of stay. Analysis of the 108 patients without major associated injuries, adjusting for age, Glasgow Coma Scale, hypotension, and type of aortic repair, showed that in early repair there was a trend toward higher mortality rate (adjusted OR 9.08 [0.88-93.78], adjusted p value = 0.064) but a significantly lower complication rate (adjusted OR 0.4 [0.18-0.96], adjusted p value 0.040) and shorter ICU stay (adjusted p value = 0.021) than the delayed repair group. A similar analysis of the 68 patients with major associated injuries, showed a strong trend toward higher mortality in the early repair group (adjusted OR 9.39 [0.93-95.18], adjusted p value = 0.058). The complication rate was similar in both groups (adjusted p value = 0.239). CONCLUSIONS Delayed repair of stable blunt TAI is associated with improved survival, irrespective of the presence or not of major associated injuries. However, delayed repair is associated with a longer length of ICU stay and in the group of patients with no major associated injuries a significantly higher complication rate.

Positive serum ethanol level and mortality in moderate to severe traumatic brain injury.

HYPOTHESIS Ethanol exposure is associated with decreased mortality in patients with moderate to severe traumatic brain injury. DESIGN Retrospective database review. SETTING Trauma centers contributing to the National Trauma Data Bank (NTDB). PATIENTS Version 6.2 of the NTDB (2000-2005) was queried for all patients with moderate to severe traumatic brain injury (head Abbreviated Injury Score > or =3) and ethanol levels measured on admission. Demographics and outcomes were compared between patients with traumatic brain injuries with and without ethanol in their blood. Logistic regression analysis was used to investigate the relationship between mortality and ethanol. MAIN OUTCOME MEASURES Mortality and complications. RESULTS A total of 38 019 patients with severe traumatic brain injuries were evaluated. Thirty-eight percent tested positive for ethanol. Ethanol-positive patients were younger (mean [SD], 37.7 [15.1] vs 44.1 [22.0] years, P < .001), had a lower Injury Severity Score (22.3 [10.0] vs 23.0 [10.3], P < .001), and a lower Glasgow Coma Scale score (10.0 [5.1] vs 11.0 [4.9], P < .001) compared with their ethanol-negative counterparts. After logistic regression analysis, ethanol was associated with reduced mortality (adjusted odds ratio, 0.88; 95% confidence interval, 0.80-0.96; P = .005) and higher complications (adjusted odds ratio, 1.24; 95% confidence interval, 1.15-1.33; P < .001). CONCLUSIONS Serum ethanol is independently associated with decreased mortality in patients with moderate to severe head injuries. Additional research is warranted to investigate the potential therapeutic implications of this association.

Patient volume per surgeon does not predict survival in adult level I trauma centers.

BACKGROUND The 1999 American College of Surgeons resources for optimal care document added the requirement that Level I trauma centers admit over 240 patients with Injury Severity Score (ISS) > 15 per year or that trauma surgeons care for at least 35 patients per year. The purpose of this study was to test the hypothesis that high volume of patients with ISS > 15 per individual trauma surgeon is associated with improved outcome. METHODS Data were obtained from the trauma registry of the five American College of Surgeons-verified adult Level I trauma centers in our mature trauma system between January 1, 1998, and March 31, 1999. Data abstracted included age, sex, Glasgow Coma Scale (GCS) score, intensive care unit length of stay, hospital length of stay, probability of survival (Ps), mechanism of injury, number of patients per each trauma surgeon and institution, and mortality. Multiple logistic regression was performed to select independent variables for modeling of survival. RESULTS From the five Level I centers there were 11,932 trauma patients in this time interval; of these, 1,754 patients (14.7%) with ISS > 15 were identified and used for analysis. Patients with ISS > 15 varied from 173 to 625 per institution; trauma surgeons varied from 8 to 25 per institution; per-surgeon patient volume varied from 0.8 to 96 per year. Logistic regression analysis revealed that the best independent predictors of survival were Ps, GCS score, age, mechanism of injury, and institutional volume (p < 0.01). Age and institutional volume correlated negatively with survival. Analysis of per-surgeon patient caseload added no additional predictive value (p = 0.44). CONCLUSION The significant independent predictors of survival in severely injured trauma patients are Ps, GCS score, age, mechanism of injury, and institutional volume. We found no statistically meaningful contribution to the prediction of survival on the basis of per-surgeon patient volume. Since this volume criterion for surgeon enpanelment and trauma center designation would not be expected to improve outcome, such a requirement should be justified by other measures or abandoned.

Redefining hypotension in traumatic brain injury

BACKGROUND Systemic hypotension is a well documented predictor of increased mortality following traumatic brain injury (TBI). Hypotension is traditionally defined as systolic blood pressure (SBP)<90 mmHg. Recent evidence defines hypotension by a higher SBP in injured (non-TBI) trauma patients. We hypothesize that hypotension threshold requires a higher SBP in isolated moderate to severe TBI. PATIENTS AND METHODS A retrospective database review of all adults (≥ 15 years) with isolated moderate to severe TBI (head abbreviated injury score (AIS)≥ 3, all other AIS ≤ 3), admitted from five Level I and eight Level II trauma centres (Los Angeles County), between 1998 and 2005. Several fit statistic analyses were performed for each admission SBP from 60 to 180 mmHg to identify the model that most accurately defined hypotension for three age groups: 15-49 years, 50-69 years, and ≥ 70 years. The main outcome variable was mortality, and the optimal definition of hypotension for each group was determined from the best fit model. Adjusted odds ratios (AOR) were then calculated to determine increased odds in mortality for the defined optimal SBP within each age group. RESULTS A total of 15,733 patients were analysed. The optimal threshold of hypotension according to the best fit model was SBP of 110 mmHg for patients 15-49 years (AOR 1.98, CI 1.65-2.39, p<0.0001), 100 mmHg for patients 50-69 years (AOR 2.20, CI 1.46-3.31, p=0.0002), and 110 mmHg for patients ≥ 70 years (AOR 1.92, CI 1.35-2.74, p=0.0003). CONCLUSIONS Patients with isolated moderate to severe TBI should be considered hypotensive for SBP<110 mmHg. Further research should confirm this new definition of hypotension by correlation with indices of perfusion.

Craniofacial and skull base trauma

BACKGROUND Traumatic craniofacial and skull base injuries require a multidisciplinary team approach. Trauma physicians must evaluate carefully, triage properly, and maintain a high index of suspicion to improve survival and enhance functional recovery. Frequently, craniofacial and skull base injuries are overlooked while treating more life-threatening injuries. Unnoticed complex craniofacial and skull base fractures, cerebrospinal fluid fistulae, and cranial nerve injuries can result in blindness, diplopia, deafness, facial paralysis, or meningitis. Early recognition of specific craniofacial and skull base injury patterns can lead to identification of associated injuries and allow for more rapid and appropriate management. CONCLUSION Early detection and treatment of craniofacial and skull base traumatic injuries should lead to decreased morbidity and mortality. This review discusses the most common of these injuries, their possible complications, and treatment.

Does insurance status matter at a public, level I trauma center?

BACKGROUND It has previously been demonstrated that a lack of insurance impedes access to health care services and may affect outcome after acute medical events. Very little data exists on the impact of insurance status on outcomes after traumatic injury. The purpose of this study was to determine whether insurance status has an impact on the outcomes of trauma patients admitted to a publicly funded county level I trauma center. PATIENTS This is a retrospective study of adult trauma patients (aged 18 years or older) admitted between January 1,1998, and December 31, 2005. Patients transferred out within 1 week of injury were excluded. Variables examined included demographics, insurance status, mechanism of injury, Injury Severity Score, Abbreviated Injury Scales, Glasgow Coma Scale, procedures performed, and outcomes. Logistic regression was used to determine independent risk factors for mortality. RESULTS Sixty-eight percent of the 29,829 patients admitted were uninsured. Uninsured patients were younger (36 versus 41, p < 0.0001) and less severely injured (Injury Severity Score 8 versus 10, p < 0.0001) but had a significantly higher mortality rate (7.0% versus 4.9%, p < 0.0001) compared with insured counterparts. Logistic regression identified uninsured status as an independent risk factor for mortality (AOR, 3.4; 95% confidence interval, 2.9-4.1; p < 0.0001). There was significant disparity between the mortality rates for uninsured and insured patients within the Black (7.1% versus 3.3%, p < 0.0001) and Hispanic (6.5% versus 4.1%, p < 0.0001) populations. No such mortality difference was observed in the white (7.2% versus 6.9%, p = 0.7) and Asian (9.7% versus 9.2%, p = 0.8) populations. CONCLUSION Despite being younger and less severely injured, uninsured trauma patients had a significantly higher mortality rate. The etiology of this discrepancy is unclear and warrants further investigation.