The impact of premorbid conditions on temporal pattern and location of adult blunt trauma hospital deaths.

BACKGROUND: This study was designed to show the importance of age, presence of premorbid conditions, and the type of injury on time and location of adult inhospital trauma mortality. METHODS: All acute blunt trauma deaths at a Level I urban trauma center between April 1, 1993 and March 31, 2003 were individually reviewed to collect data on the following variables: age, gender, presence and number of premorbid conditions, mechanisms of trauma, location of death, acute transfer from another hospital, delay to death, initial Glasgow Coma Score (GCS), Abbreviated Injury Score (AIS), Injury Severity Score (ISS), and revised trauma score (RTS). Bivariate analysis using simple logistic regression was used to show the association between each variable and delay to death. Variables significantly associated with death underwent multivariate analysis to yield adjusted odds ratios (aORs) with 95% confidence interval (CI). RESULTS: During the study period there were 463 blunt trauma deaths (6.8%). Their mean age was 67.5 years, mean ISS was 22.6, mean GCS was 11.0, and 55.3% were male. Most deaths occurred in either the intensive care unit (45.8%) or the ward (46.4%); there were few deaths in the emergency department (6.8%) or the operating room (0.4%). The following were significant bivariate predictors for death: presence of premorbid conditions, number of premorbid conditions, age >60, pulmonary diseases, cardiac diseases, diabetes mellitus, neurologic diseases, GCS, AIS > or =4, and ISS. Multivariate analysis demonstrated the following significant findings: patients with severe thoracic injuries were significantly more likely to die in the first 6 hours (aOR = 1.37; CI = 1.12-1.68; p = 0.002); and patients with severe head injuries were more likely to die after 48 hours (aOR = 1.275; CI = 1.158-1.405; p = 0.0001). Older patients and those with neurologic diseases were more likely to die later and in a hospital ward (aOR = 2.18; CI = 1.25-3.81; p = 0.006). Men and women differed as to age, ISS, mechanism of injury, and type of injury, but not as to delay to death. CONCLUSIONS: Age, body area injured, and presence and type of premorbid conditions are significant predictors of location of and delay to death after blunt trauma. We think that incorporating information on premorbid conditions is essential for mortality analysis in an aging population.

Surgical management of blunt thoracic and abdominal injuries in Quebec: a limited volume.

BACKGROUND: Trauma care of thoracic and abdominal injuries is currently in turmoil because of both a decrease in the number of these injuries and a concomitant increase in their nonsurgical management. The goal of this study was to evaluate the incidence of thoracic and abdominal injuries in the province of Quebec and the number of associated surgical procedures. METHODS: Patients with blunt thoracic or abdominal injuries taken to a tertiary trauma center in the province of Quebec from April 1, 1998 to March 31, 2002 were identified. Patients who were dead on arrival were excluded. Only patients with an Abbreviated Injury Scale score > or =2 for the thoracic or abdominal regions were included. RESULTS: During the study period, a total of 16,430 blunt trauma patients were admitted to one of the four trauma centers. A total of 2,660 (16.2%) patients sustained thoracic and/or abdominal injuries with an Abbreviated Injury Scale score >1. Among these, the median Injury Severity Score was 24 (range: 4-75) and the in-hospital mortality rate was 11.0%. There were 2,196 patients (82.5%) with thoracic injuries, 977 patients (36.7%) with abdominal injuries, and 520 patients (19.5%) with injuries to both regions. A surgical intervention was undertaken in 76 patients with thoracic injuries (3.5%) and in 414 patients with abdominal injuries (42.3%). On average, 4.7 thoracic and 28.8 abdominal trauma procedures were performed per center, yearly. Each trauma surgeon performed, on average, less than one thoracic and less than five abdominal trauma procedures yearly. CONCLUSIONS: The incidence of blunt thoracic and abdominal injuries needing surgical intervention is low in Quebec tertiary trauma centers. The competence of general surgeons in trauma-related procedures might be compromised by such low patient volume unless they frequently perform non-trauma surgical procedures. We think that in Quebec, trauma care must be provided by surgeons who practice both acute emergency and elective surgical care in addition to trauma care. These findings should have an important impact on the development of on-going education and resident training programs.

Is the delay to surgery for isolated hip fracture predictive of outcome in efficient systems?

BACKGROUND: Adverse outcomes for patients with isolated hip fracture have been documented when preoperative delay is longer than 48 hours. An efficient system will have the capacity to repair all hip fractures within 48 hours. We hypothesized that in an efficient system, there would be a medical justification for a delay greater than 48 hours. The purpose of this study was to identify the causes and outcome of delay for hip surgery in an efficient system. METHODS: All patients with isolated hip fracture admitted to a regional trauma center from April 1993 to March 2003 were reviewed. Demographics, presence of comorbidity, preoperative delay, complications, and mortality were collected. Univariate and multivariate analysis were carried out. RESULTS: The cohort included 977 patients. Overall mortality was 12.2%. Surgery was performed within 24 hours in 53% of cases and within 48 hours in 87% of cases. The presence of comorbidity partly explained longer (>48 hours) surgical delays. Multivariate analysis revealed that age greater than 65, male sex, and the presence of pulmonary and cardiac comorbid conditions or an active cancer but not surgical delay were associated with mortality and complications. However, surgical delay was associated with longer postsurgical hospital stay, independently of the presence of comorbidity or increasing age. CONCLUSIONS: Preoperative delay does not entail adverse outcomes when the surgery is delayed to allow for treatment of comorbid medical conditions. Preoperative delay is associated with a longer hospital stay. The presence of comorbidity only partly explains preoperative delay and adverse outcomes. A prospective study coding for the severity of comorbid conditions and the justification of the preoperative delay will be required to fully elucidate the link between delay and outcome.

A simple fall in the elderly: not so simple.

BACKGROUND: The goal of this study was to evaluate the burden of falls in the elderly in a Canadian tertiary trauma center. METHODS: Patients admitted to Charles-LeMoyne Hospital with a low velocity fall (LVF) from April 1, 1993 to March 31, 2000 were individually reviewed. Elderly was defined as age 65 years and older. A region was considered to be injured if Abbreviated Injury Scale was greater than or equal to 2. RESULTS: There were 2,333 patients with LVF, 41.4% of all blunt trauma admissions. Median Injury Severity Score was 9 for elderly compared with 5 for young (p < 0.001). Injuries were significantly more frequent to head, face, thorax, and lower limbs in the elderly. Mortality (13.4% versus 0.9%; p < 0.001), length of stay (median = 15 versus 3 days; p < 0.001) and long-term care facility reference (19.3% versus 1.1%, p < 0.001) were significantly higher in the elderly. CONCLUSIONS: LVF is a frequent cause of admission for trauma in the elderly. Despite the apparent benign nature of the mechanism, LVF is associated with more severe injuries and worse outcome.

Paying the price of excluding patients from a trauma registry.

BACKGROUND: The goal of this study was to evaluate the impact of different trauma registry exclusion criteria on the assessment of trauma populations and outcome. METHODS: All patients admitted to a Canadian regional trauma center from April 1, 1993 to March 31, 2002 with a diagnosis of trauma (ICD-9 codes 800 to 959) were reviewed. TOTAL included everyone. REGISTRY included only patients meeting any of four criteria: death during hospital stay, transfer received from another hospital, admission to the intensive care unit, or hospital stay of 3 days or more. NOHIP excluded patients with isolated hip fracture. REG/NOHIP combined both. ISS12 and ISS15 excluded patients with ISS <12 and 15, respectively. RESULTS: There were 6,839 trauma patients. The percentage of excluded patients by group was: REGISTRY, 21.2%; NOHIP, 14.7%; REG/NOHIP, 34.9%; ISS12, 75%; and ISS15, 80.3%. Median length of stay was 7 days. Exclusions represented a total number of hospitalization days varying from 1.9% to 65.5% of TOTAL. Mortality was 6.9% for TOTAL, 8.6% for REGISTRY (p < 0.001), 5.7% for NOHIP (p = 0.009), 7.5% for REG/NOHIP (p=NS), 16.1% for ISS12 (p < 0.001), and 20.4% for ISS15 (p < 0.001). In groups with exclusions, transfer to long-term care varied from 0.14% to 23.5% in the excluded patients. For rehabilitation, these percentages varied from 0.14% to 17.6%. CONCLUSIONS: Registry exclusion criteria significantly alter the apparent severity of injury and resource utilization. The use of divergent exclusion criteria in the analysis of trauma registry data may be misleading.

Comorbidity and age are both independent predictors of length of hospitalization in trauma patients.

BACKGROUND: Length of hospitalization is a good indicator of resource utilization. Older patients are increasingly suffering trauma, and comorbid medical conditions are also increasing. Our objective was to determine the separate and combined effect of these 2 factors on length of hospital stay for trauma patients in a tertiary trauma centre. METHODS: All 994 consecutive trauma patients surviving to hospital discharge between Apr. 1, 2000, and Mar. 31, 2001, were identified. Patient characteristics, injury severity and length of hospitalization were obtained from the hospital trauma registry. Each medical record was then reviewed for completeness of information and assessment of comorbid conditions. A multivariate linear regression model was developed to predict logarithmic length of stay from age and presence of a cormorbid condition while adjusting for the Injury Severity Score (ISS). RESULTS: The mean age of the patients was 49.7 (range from 14-100) years and median ISS was 9 (range from 1-50). At least 1 comorbid condition was present in 321 (32%) patients. Mean length of hospital stay was 15.3 days. The proportion of patients with a comorbid condition increased steadily with age, from 8.7% before the age of 55 years to 92% at 85 or more years of age (p < 0.001). According to the multivariate model, the presence of comorbidity, age and ISS were all independent predictors of hospital stay (p < 0.001). When applied to patients with the mean ISS value of 9, the model showed an increase in length of hospitalization for patients with a comorbid condition over those without; (3.6 v. 13.1 d for patients < 55 and > or = 85 yr respectively). Length of hospital stay increased particularly with neurologic and pulmonary problems. CONCLUSIONS: Comorbidity and age were both independently significant predictors of length of hospitalization over and beyond that which is expected based on the severity of the injuries. With an aging population, this phenomenon should severely affect resource utilization in trauma centres in the near future. Researchers should take account of both age and comorbidity in order to compare trauma populations.

Penetrating thoracoabdominal injuries in Quebec: implications for surgical training and maintenance of competence.

BACKGROUND: The frequency of penetrating trauma is low in Canada. Current recommendations for the care of patients with penetrating injuries originate from inner city trauma centres with a high volume of such injuries and may not apply to Canada. The purpose of this study was to review the incidence and treatment of penetrating thoracoabdominal injuries in the 4 tertiary trauma centres in Quebec. METHODS: We identified all patients with penetrating thoracic or abdominal injuries who were taken to any of the 4 tertiary trauma centres in the province of Quebec between Apr. 1, 1998, and Mar. 31, 2001. Patients who were dead on arrival were excluded. Only patients with an Abbreviated Injury Scale of 2 or greater for the thoracic or abdominal regions were included. RESULTS: In total, 245 patients meeting our inclusion criteria were identified. Of these 223 (91%) were male. The mean (and standard deviation) age was 33.8 (13.2) years; range 15-90 years. The median Injury Severity Score was 10 (range 4-75). Overall in-hospital mortality was 6.9%. There were 203 patients (82.8%) with thoracic injuries and 192 patients (78.4%) with abdominal injuries. Fifty (20.4%) of these patients had injuries to both regions. A thoracotomy was carried out in 48 (31.4%) of 153 patients who had injuries to the thorax, and the abdomen was explored in 133 (93.7%) of the 142 patients with abdominal injuries. The incidence of these injuries in the study period varied from 3 to 49 cases per centre. CONCLUSIONS: The annual incidence of penetrating thoracoabdominal injuries is extremely low in all 4 of Quebec's tertiary trauma centres, and the number of thoracoabdominal procedures is even lower. Such a low exposure may jeopardize education and clinical competence. We need to rethink our educational strategies both for residents and for continuing medical education. New approaches to training and maintenance of competence must be developed.

Should patients with isolated hip fractures be included in trauma registries?

BACKGROUND: Patients with isolated hip fractures are frequently excluded from trauma registries. The goal of this study was to show that patients with these injuries have higher resource use and poorer outcomes than the rest of the trauma population. METHODS: The Quebec Trauma Registry was used to identify all trauma patients from April 1, 1998, to March 31, 2003. Patients who were dead on arrival at the emergency room were excluded. Isolated hip fracture (HIP) was defined as a diagnosis of a single fracture to the neck of the femur (Abbreviated Injury Scale 1990 codes 851808.3, 851810.3, 851812.3, and 851818.3) secondary to a fall and for which the Injury Severity Score was 9 or 10 (no other Abbreviated Injury Scale code higher than 1). Patients with all other trauma diagnosis (OT) were used for comparison. Outcome variables were length of hospital stay, length of intensive care unit (ICU) stay, in-hospital complications, and status and orientation at discharge. Chi-square and Wilcoxon rank-sum tests were used. RESULTS: There were 68,422 patients: 14,426 (21.1%) HIP patients and 53,996 (78.9%) OT patients. The median Injury Severity Score was 9 for HIP (range, 9-10) and 9 for OT (range, 1-75). Mean length of hospital stay was 18.4 days for HIP compared with 11.7 days for OT (p < 0.0001). HIP patients represented 29.5% of the total hospital stay. ICU stay was required for 1,353 HIP patients (9.4%) and for 12,395 (23.0%) OT patients (p < 0.0001). Mean ICU stay was 3.9 days for HIP compared with 5.5 days for OT (p = 0.0006). In-hospital mortality was 8.5% in HIP compared with 3.7% in OT (p < 0.0001). HIP represented 62.7% of patients referred for long-term care and 39.3% of patients referred to a rehabilitation center. CONCLUSION: Patients with HIP represented 21.1% of admissions while accounting for 42% of total days of hospitalization and 38% of deaths. Patients with hip fractures have a significantly higher risk of death, prolonged hospital stay, and complication rate, and are more often transferred to a rehabilitation center or to a long-term nursing home than the rest of the trauma population despite lower severity. They require multidisciplinary care typical of the rest of the trauma population and should be included in the trauma registry if the registry is to document the full outcome and resource use of the trauma population.

Improving the TRISS methodology by restructuring age categories and adding comorbidities.

BACKGROUND: The Trauma and Injury Severity Score (TRISS) methodology was developed to predict the probability of survival after trauma. Despite many criticisms, this methodology remains in common use. The purpose of this study was to show that improving the stratification for age and adding an adjustment for comorbidity significantly increases the predictive accuracy of the TRISS model. METHODS: The trauma registry and the hospital administrative database of a regional trauma center were used to identify all blunt trauma patients older than 14 years of age admitted with International Classification of Diseases, Ninth Revision codes 800 to 959 from April 1993 to March 2001. Each individual medical record was then reviewed to ascertain the Revised Trauma Score, the Injury Severity Score, the age of the patients, and the presence of eight comorbidities. The outcome variable was the status at discharge: alive or dead. The study population was divided into two subsamples of equal size using a random sampling method. Logistic regression was used to develop models on the first subsample; a second subsample was used for cross-validation of the models. The original TRISS and three TRISS-derived models were created using different categorizations of Revised Trauma Score, Injury Severity Score, and age. A new model labeled TRISSCOM was created that included an additional term for the presence of comorbidity. RESULTS: There were 5,672 blunt trauma patients, 2,836 in each group. For original TRISS, the Hosmer-Lemeshow statistic (HL) was 179.1 and the area under the receiver operating characteristic (AUROC) curve was 0.873. Sensitivity and specificity were 99.0% and 27.8%, respectively. For the best modified TRISS model, the HL statistic was 20.35, the AUROC curve was 0.902, the sensitivity was 99.0%, and the specificity was 27.8%. For TRISSCOM, the HL statistic was 14.95 and the AUROC curve was 0.918. Sensitivity and specificity were 99.0% and 29.7%, respectively. The difference between the two models almost reached statistical significance (p = 0.086). When TRISSCOM was applied to the cross-validation group, the HL statistic was 10.48 and the AUROC curve was 0.914. The sensitivity was 98.6% and the specificity was 34.9%. CONCLUSION: TRISSCOM can predict survival more accurately than models that do not include comorbidity. A better categorization of age and the inclusion of comorbid conditions in the logistic model significantly improves the predictive performance of TRISS.

Preinjury warfarin use among elderly patients with closed head injuries in a trauma center.

BACKGROUND: This study aimed to determine the impact of warfarin use on the severity of injury among elderly patients presenting with closed head injuries. METHODS: A cohort of patients 55 years of age or older with closed head injuries taken to a tertiary trauma center between April 1993 and March 2001 was retrospectively identified. Patient characteristics, mechanism of injury, type and severity of injury, and hospital survival data were obtained from the trauma registry. Each case then was reviewed for completeness of information, assessment of preinjury warfarin use, and comorbidity. RESULTS: Among the 384 patients presenting with closed head injuries, 35 (9%) were receiving warfarin before their trauma. As compared with nonusers, anticoagulated patients had a higher frequency of isolated head trauma (54% vs. 32%; p = 0.008), more severe head injuries (65.7% vs. 44.1%; p = 0.02), and a higher rate of mortality (40% vs. 21%, p = 0.01). These associations remained evident even after population differences in age, gender, comorbidities, and mechanism of injury were taken into account. Indeed, according to multivariate logistic regression models, warfarin use was associated with a statistically significant risk of death (odds ratio [OR], 2.73; 95% confidence interval [CI], 1.22-6.12), statistically significant odds for more severe head injury (OR, 2.39; 95% CI, 1.10-5.17), and odds for isolated head injury that almost reached statistical significance (OR, 1.79; 95% CI, 0.82-3.90). CONCLUSIONS: Among patients 55 years of age or older who present with closed head injury, the use of warfarin before trauma appears to be associated with a higher frequency of isolated head trauma, more severe head trauma, and a higher likelihood of death. The findings of this retrospective study support the concern about the adverse effects of anticoagulants in cases of head trauma.

Elderly trauma patients with rib fractures are at greater risk of death and pneumonia.

BACKGROUND: The purpose of this study was to show that elderly patients admitted with rib fractures after blunt trauma have increased mortality. METHODS: Demographic, injury severity, and outcome data on a cohort of consecutive adult trauma admissions with rib fractures to a tertiary care trauma center from April 1, 1993, to March 31, 2000, were extracted from our trauma registry. RESULTS: Among 4,325 blunt trauma admissions, there were 405 (9.4%) patients with rib fractures; 113 were aged > or = 65. Injuries were severe, with Injury Severity Score (ISS) > or = 16 in 54.8% of cases, a mean hospital stay of 26.8 +/- 43.7 days, and 28.6% of patients requiring mechanical ventilation. Mortality (19.5% vs. 9.3%; p < 0.05), presence of comorbidity (61.1% vs. 8.6%; p < 0.0001), and falls (14.6% vs. 0.7%; p < 0.0001) were significantly higher in patients aged > or = 65 despite significantly lower ISS (p = 0.031), higher Glasgow Coma Scale score (p = 0.0003), and higher Revised Trauma Score (p < 0.0001). After adjusting for severity (i.e., ISS and Revised Trauma Score), comorbidity, and multiple rib fractures, patients aged > or = 65 had five times the odds of dying when compared with those < 65 years old. CONCLUSION: Despite lower indices of injury severity, even after taking account of comorbidities, mortality was significantly increased in elderly patients admitted to a trauma center with rib fractures.

Impact of deferred treatment of blunt diaphragmatic rupture: a 15-year experience in six trauma centers in Quebec.

BACKGROUND: The purpose of this study was to show that blunt diaphragmatic rupture does not require immediate emergency operation in the absence of other indications. METHODS: We reviewed all patients with blunt diaphragmatic rupture admitted within 24 hours of injury to one of six university trauma centers providing trauma care for the province of Quebec from April 1, 1984, to March 31, 1999. Multivariate analysis of demographic profiles, severity indices, indications for operation, and preoperative delays was performed. RESULTS: There were 160 patients (91 men and 69 women) with blunt diaphragmatic rupture. Mean age was 40.1 +/- 16.2 years. Mean Injury Severity Score was 26.9 +/- 11.5 and mortality was 14.4%. Patients undergoing emergency surgery for indications other than diaphragmatic rupture had a significantly higher Injury Severity Score than those undergoing surgery for repair of diaphragmatic rupture alone (34.7 +/- 10.7 vs. 22.0 +/- 9.0, p < 0.001). In patients undergoing surgery for diaphragmatic rupture alone, delay before repair of the diaphragmatic hernia did not lead to an increased mortality compared with patients undergoing immediate surgery (3.4% vs. 5.0%, p = NS). CONCLUSION: Blunt diaphragmatic rupture in the absence of other surgical injuries carries low mortality. Operative repair of diaphragmatic rupture can be deferred without appreciable increased mortality if no other indication mandates immediate surgery.