International Classification of Disease based Injury Severity Score (ICISS): a comparison of methodologies applied to linked data from New South Wales, Australia

BACKGROUND

The International Classification of Disease Injury Severity Score (ICISS) provides an efficient method to determine injury severity in hospitalised injury patients. Injury severity metrics are of particular interest for the tracking of road transport injury rates and trends. The aims of this study were to calculate ICISS using linked morbidity and mortality datasets and to compare predictive ability of various methods and metrics.

METHODS

This was a retrospective analysis of Admitted Patient Data Collection records from New South Wales, Australia, linked with mortality data. Using a split sample approach, design data (2008-2014; n=1 035 174 periods of care) was used to derive survival risk ratios and calculate various ICISS scales based on in-hospital death and 3-month death. These scales were applied to testing data (2015-2017; n=575 306). Logistic regression modelling was used to determine model discrimination and calibration.

RESULTS

There were 12 347 (1.19%) in-hospital deaths and 29 275 (2.83%) 3-month deaths in the design data. Model discrimination ranged from acceptable to excellent (area under the curve 0.75-0.88). Serious injury (ICISS≤0.941) rates in the testing data varied, with a range of 10%-31% depending on the methodology. The 'worst injury' ICISS was always superior to 'multiplicative injury' ICISS in model discrimination and calibration.

CONCLUSIONS

In-hospital death and 3-month death were used to generate ICISS; the former is recommended for settings with a focus on short-term threat to life, such as in trauma care settings. The 3-month death approach is recommended for outcomes beyond immediate clinical care, such as injury compensation schemes.

An evaluation of the "Obesity Paradox" in isolated blunt abdominal trauma in the United States

BACKGROUND

The obesity paradox theorizes a survival benefit in trauma patients secondary to the cushioning effect of adiposity. We aim to evaluate the impact of body mass index (BMI) on abdominal injury severity, morbidity, and mortality in adults with isolated, blunt abdominal trauma in the United States.

METHODS

We reviewed the National Trauma Data Bank (2013-2021) for adults sustaining isolated, blunt abdominal trauma stratified by BMI. We performed a doubly robust, augmented inverse-propensity weighted multivariable logistic regression to estimate the average treatment effect (ATE) of BMI on mortality and the presence of abdominal organ injury.

RESULTS

36,350 patients met the inclusion criteria. In our study, 41.4 % of patients were normal-weight (BMI 18.5-24.9), 20.6 % were obese (BMI 30-39.9), and 4.7 % were severely obese (BMI≥40). In these cohorts, the abdominal abbreviated injury scale (AIS) was 2 (2 -3). Obese and severely obese patients had significantly reduced presence of pancreas, spleen, liver, kidney, and small bowel injuries. The predicted probability of abdominal AIS severity decreased significantly with increasing BMI. Crude mortality was significantly higher in obese (1.3 %) and severely obese patients (1.3 %) compared to normal-weight patients (0.7 %). Obese and severely obese patients demonstrated non-statistically significant changes in the mortality of +26.4 % (ATE 0.264, 95 %CI -0.108-0.637, p = 0.164) and +55.5 % (ATE 0.555, 95 %CI -0.284-1.394, p = 0.195) respectively, compared to normal weight patients.

CONCLUSION

BMI may protect against abdominal injury in adults with isolated, blunt abdominal trauma. Mortality did not decrease in association with increasing BMI, as this may be offset by the increase in co-morbidities in this population.

Coronary Artery Calcification and Risk of Cardiac Complication in Geriatric Trauma Population

BACKGROUND

Better means of identifying patients with increased cardiac complication (CC) risk is needed. Coronary artery calcification (CAC) is reported on routine chest CT scans. We assessed the correlation of CAC and CCs in the geriatric trauma population.

STUDY DESIGN

A prospective, observational study of patients 55 years and older who had chest CT scan from May to September 2022 at a level 1 trauma center. Radiologists scored CAC as none, mild, moderate, or severe. None-to-mild CAC (NM-CAC) and moderate-to-severe CAC (MS-CAC) were grouped and in-hospital CCs assessed (arrhythmia, ST elevation myocardial infarction [STEMI], non-STEMI, congestive heart failure, pulmonary edema, cardiac arrest, cardiogenic shock, and cardiac mortality). Univariate and bivariate analyses were performed.

RESULTS

Five hundred sixty-nine patients had a chest CT, of them 12 were excluded due to missing CAC severity. Of 557 patients, 442 (79.3%) had none-to-mild CAC and 115 (20.7%) has MS-CAC; the MS-CAC group was older (73.3 vs 67.4 years) with fewer male patients (48.7% vs 54.5%), had higher cardiac-related comorbidities, and had higher abbreviated injury scale chest injury scores. The MS-CAC group had an increased rate of CC (odds ratio [OR] 1.81, p = 0.016). Cardiac complications statistically more common in MS-CAC were congestive heart failure (OR 3.41, p = 0.003); cardiogenic shock (OR 3.3, p = 0.006); non-STEMI I or II (OR 2.8, p = 0.017); STEMI (OR 5.9, p = 0.029); and cardiac-caused mortality (OR 5.27, p = 0.036). No statistical significance between pulmonary edema (p = 0.6), new-onset arrhythmia (p = 0.74), or cardiac arrest (p = 0.193).

CONCLUSIONS

CAC as reported on chest CT scans demonstrates a significant correlation with CC and should warrant additional cardiac monitoring.

In-hospital mortality after prehospital endotracheal intubation versus alternative methods of airway management in trauma patients. A cohort study from the TraumaRegister DGU®

PURPOSE

Prehospital airway management in trauma is a key component of care and is associated with particular risks. Endotracheal intubation (ETI) is the gold standard, while extraglottic airway devices (EGAs) are recommended alternatives. There is limited evidence comparing their effectiveness. In this retrospective analysis from the TraumaRegister DGU®, we compared ETI with EGA in prehospital airway management regarding in-hospital mortality in patients with trauma.

METHODS

We included cases only from German hospitals with a minimum Abbreviated Injury Scale score ≥ 2 and age ≥ 16 years. All patients without prehospital airway protection were excluded. We performed a multivariate logistic regression to adjust with the outcome measure of hospital mortality.

RESULTS

We included n = 10,408 cases of whom 92.5% received ETI and 7.5% EGA. The mean injury severity score was higher in the ETI group (28.8 ± 14.2) than in the EGA group (26.3 ± 14.2), and in-hospital mortality was comparable: ETI 33.0%; EGA 30.7% (27.5 to 33.9). After conducting logistic regression, the odds ratio for mortality in the ETI group was 1.091 (0.87 to 1.37). The standardized mortality ratio was 1.04 (1.01 to 1.07) in the ETI group and 1.1 (1.02 to 1.26) in the EGA group.

CONCLUSIONS

There was no significant difference in mortality rates between the use of ETI or EGA, or the ratio of expected versus observed mortality when using ETI.

Predicting the Future in Trauma: Trauma and Injury Severity Score Loses Accuracy and Validity for Late Deaths After Injury

BACKGROUND

The Trauma and Injury Severity Score (TRISS) is widely used to predict mortality in trauma patients, but its performance metrics have not been analyzed for early vs later deaths. Therefore, we aimed to investigate the impact of time to death on the accuracy of TRISS.

METHODS

Patients from 2013 to 2018 American College of Surgeons Trauma Quality Improvement Program database were included. We compared predicted survival by TRISS using the areas under receiver operating characteristic curves (AUCs) and calibration curves between different cut-off times and subgroups. We further compared early (≤72 hr) and late (>72 hr) deaths based on mechanisms and severity.

RESULTS

Among the 1,180,745 patients, the total mortality rate was 6.4%, with 59% early deaths and 41% late deaths. The AUC of TRISS for all patients was .919 (95% CI: .918-.921) for ≤72 hr survival and .845 (95% CI: .843-.848) for >72 hr survival. Significant discrepancies in AUCs between the early and late death groups existed in all cohorts based on blunt/penetrating mechanisms and severity. TRISS predicted well in early survival of penetrating injury but was less reliable in late survival of penetrating injury and all blunt injury. TRISS tended to underestimate survival, particularly for patients with lower probability of survival, with increased discrepancies seen for predicting late deaths.

CONCLUSIONS

The predictive ability of TRISS varies significantly based on the timing of deaths and key injury factors. TRISS may be best utilized in predicting early survival in penetrating injury, but its reliability and accuracy diminish when predicting late deaths for all kinds of injury.

Negative laparotomy rates and outcomes following blunt traumatic injury in the United States

INTRODUCTION

Exploratory laparotomy remains the mainstay of treatment following blunt abdominal trauma. However, the decision to operate can be difficult in hemodynamically stable patients with unreliable physical exams or equivocal imaging findings. The risk of a negative laparotomy and the subsequent complications must be weighed against the potential morbidity and mortality of a missed abdominal injury. Our study aims to evaluate trends and the effect of negative laparotomies on morbidity and mortality in adults with blunt traumatic injuries in the United States.

METHODS

We reviewed the National Trauma Data Bank (2007-2019) for adults with blunt traumatic injuries who underwent an exploratory laparotomy. Positive or negative laparotomy of abdominal injury was compared. We performed bivariate analysis and a modified Poisson regression to estimate the effect of negative laparotomy on mortality. A sub-analysis of patients who underwent computed tomography (CT) of the abdomen and pelvis was performed.

RESULTS

92,800 patients met the inclusion criteria of the primary analysis. Negative laparotomy rates were 12.0% in this population, down-trending throughout the study. Negative laparotomy patients had a significantly higher crude mortality (31.1% vs. 20.5%, p < 0.001), despite lower injury severity scores (20 (10-29) vs. 25 (16-35), p < 0.001) than positive laparotomy patients. Patients that underwent negative laparotomy had a 33% higher risk for mortality (RR1.33, 95% CI 1.28-1.37, P < 0.001) than positive laparotomy patients after adjusting for pertinent covariates. Patients that underwent CT abdomen/pelvis imaging (n = 45,654) had a lower rate of negative laparotomy (11.1%) and decreased difference in crude mortality (22.6% vs. 14.1%, p < 0.001) compared to positive laparotomy patients. However, the relative risk for mortality remained high at 37% (RR 1.37, 95% CI 1.29 - 1.46, p < 0.001) for this sub-cohort.

CONCLUSION

Negative laparotomy rates in adults with blunt traumatic injuries are trending down in the United States but remains substantial and may show improvement with increased use of diagnostic imaging. Negative laparotomy has a relative risk for mortality of 33% despite lower injury severity. Thus, surgical exploration in this population should be thoughtfully undertaken with appropriate evaluation via physical exam and diagnostic imaging to prevent unnecessary morbidity and mortality.

Insurance status and traumatized patients' outcomes: a report from the national trauma registry of Iran

BACKGROUND

Trauma care is one of the most expensive medical procedures that is significantly affected by factors like insurance status. Providing medical care to injured patients has a significant impact on patients' prognosis. This study examined whether insurance status was associated with different outcomes, including hospital length of stay (HLOS), mortality, and Intensive Care Unit (ICU) admission.

METHODS

This prospective study analyzed the data of traumatized patients who had been registered in the National Trauma Registry of Iran (NTRI), and hospitalized at Sina Hospital, Tehran, Iran, from March 22, 2016, to February 8, 2021. Given the type of insurance, the insured patients were classified as basic, road traffic, and foreign nationality. The outcomes of in-hospital death, ICU admission, and HLOS between insured and uninsured patients, and then different insurance statuses, were compared using regression models.

RESULT

A total of 5014 patients were included in the study. 49% of patients (n = 2458) had road traffic insurance, 35.2% (n = 1766) basic insurance, 10.5% (n = 528) were uninsured, and 5.2% (n = 262) had foreign nationality insurance. The mean age of patients with basic, road traffic insurance, foreign nationality, and uninsured patients was 45.2 (SD = 22.3), 37.8 (SD = 15.8), 27.8 (SD = 13.3), and 32.4 (SD = 11.9) years, respectively. There was a statistically significant association between insurance status and mean age. Based on these results, the mean age of patients with basic insurance was higher than other groups (p < 0.001). Additionally, 85.6% of the patients were male, with male to female ratio of 9.64 in road traffic insurance, 2.99 in basic insurance, 14.4 in foreign nationality, and 16 in uninsured patients. There was no statistically significant difference between in-hospital mortality in insured and uninsured patients, 98 (2.3%) vs. 12 (2.3%), respectively. The odds of in-hospital mortality in uninsured patients were 1.04 times the odds of in-hospital death in insured patients [Crude OR: 1.04, 95%CI: 0.58 to 1.90]. Multiple logistic regression showed that after adjusting for age, sex, ISS, and Cause of trauma, the odds of in-hospital death in uninsured patients were 2.97 times the odds of in-hospital death in insured patients [adjusted OR: 2.97, 95%CI: 1.43 to 6.21].

CONCLUSION

This study shows that having insurance can change the ICU admission, death, and HLOS in traumatized patients. The results of this study can provide essential data for national health policy for minimizing the disparities among different insurance statuses and proper use of medical resources.

Incidence of Traumatic Sciatic Nerve Injury in Association with Acetabular Fracture: A Retrospective Observational Single-Center Study

Purpose

Patients and Methods

Results

Conclusion

Opportunities to Improve Palliative Care Delivery in Trauma Critical Illness

BACKGROUND

Despite recommendations to integrate palliative care (PC) into care for critically ill trauma patients, little is known about current PC practices in trauma care to inform opportunities for improvement.

OBJECTIVE

Describe patterns of PC delivery among a large, critically ill trauma cohort.

SETTING/SUBJECTS

Retrospective cohort study of adult (≥18 years) trauma patients admitted to an intensive care unit (ICU) at an urban, level one trauma center in the United States from March 1, 2017 to March 1, 2019.

METHODS

We linked the electronic medical record with the institutional trauma registry. PC process measures included a PC consult order, advance care planning (ACP) note, and hospice use. Unadjusted results are reported for the total population, decedents, and subgroups at risk for poor outcomes (age ≥55 years, Black race ≥1 pre-existing comorbidity, and severe injury) after trauma.

RESULTS

Among 1309 eligible admissions, 902 (68.9%) were male, 640 (48.9%) were Black, and 654 (50.0%) were ≥55 years old. Eighty-one (6.2%) patients received a PC consult order, 66 (5.0%) had an ACP note, and 13 (1.1%) were discharged to hospice. Among decedents (N = 91; 7%), 28 (30.8%) received a PC consult order and 36 (39.6%) had an ACP note. For high-risk subgroups, PC consult orders and ACP note rates ranged from 4.5-12.8% and 4.5-11.8%, respectively.

CONCLUSION

PC delivery was rare among this cohort, including those at high risk for poor outcomes. Urgent efforts are needed to identify barriers to and develop targeted interventions for high quality PC delivery in trauma ICU care.

International classification of disease based injury severity score (ICISS): A data linkage study of hospital and death data in Victoria, Australia

BACKGROUND

Surveillance of severe injury incidence and prevalence using ICD-based injury severity scores (ICISS) requires valid, locally applicable diagnosis-specific survival probabilities (DSPs). This study aims to derive and validate ICISS in Victoria, Australia, and compare various ICISS methodologies in terms of accuracy and calculated severe injury prevalence.

METHODS

This study used injury admissions (ICD-10-AM coded) from the Victorian Admitted Episodes Database (VAED) linked with death data (Cause of Death - Unit Record Files: CODURF). Using design data (July 2008 - June 2014; n = 720,759), various ICISS scales were derived, based on (i) in-hospital and (ii) three-month mortality. These scales were applied to testing data (July 2014 - December 2016; n = 334,363). Logistic regression modelling was used to determine model discrimination and calibration.

RESULTS

In the design data, there were 6,337(0.9%) hospital deaths and 17,514(2.4%) three-months deaths; in the testing data, there were 2,700(0.8%) hospital deaths and 8,425(2.5%) three-month deaths. Newly developed ICISS scales had acceptable to outstanding discrimination, with Area Under the Curve ranging from 0.758 to 0.910. Age-specific ICISS scales were superior to general ICISS scales in model discrimination but inferior in model calibration. Calculated severe injury (ICISS ≤0.941) prevalence in the testing data ranged from 2% to 24%, depending on which mortality outcomes were used to calculate DRGs.

CONCLUSIONS

This study provides local, validated ICISS scores that can be used in Victoria. It is recommended that age group stratified ICISS based on the worst-injury method is used. From the comparison of various ICISS scores, reflecting the range of ICISS permutations that are currently in use, care should be taken to compare ICISS methodology before comparing severe injury prevalence per population, injury cause, and time trends.

Trauma Risk Score Matching for Observational Studies in Orthopedic Trauma

OBJECTIVES

To determine if matching by trauma risk score is non-inferior to matching by chronic comorbidities and/or a combination of demographic and patient characteristics in observational studies of acute trauma in a hip fracture model.

DESIGN

Retrospective cohort study SETTING: Level-1 Trauma Center PATIENTS: 1,590 hip fracture [AO/OTA 31A and 31B] patients age 55 and over treated between October 2014 and February 2020 at 4 hospitals within a single academic medical center.

INTERVENTION

Repeatedly matching randomized subsets of patients by (1) Score for Trauma Triage in Geriatric and Middle-Aged (STTGMA), (2) Charlson Comorbidity Index (CCI), or (3) a combination of sex, age, CCI and body mass index (BMI).

MAIN OUTCOME MEASUREMENTS

"Matching failures" where rate of significant differences in variables of matched cohorts exceeds the 5% expected by chance.

RESULTS

STTGMA and combination matching resulted in no "matching failures". Matching by CCI alone resulted in "matching failures" of BMI, ASA class, STTGMA, major complications, sepsis, pneumonia, acute respiratory failure, and 90-day readmission.

CONCLUSIONS

STTGMA matching in observational cohort studies is less likely to yield significant differences of demographics and outcomes than CCI matching. STTGMA matching is noninferior to matching a combination of demographic variables optimized for each treatment cohort. STTGMA matching is apt to reflect equipoise of health at admission and outcome likelihood in observational cohort studies of orthopedic trauma, while maintaining consistent weighting of demographic and injury characteristic variables that may expand the generalizability of these studies.

LEVEL OF EVIDENCE

Level III.

Assessment of earthquake casualties and comparison of accuracy of five injury triage methods: evidence from a retrospective study

OBJECTIVE

The use of an injury triage method among earthquake injury patients can facilitate the reasonable allocation of resources, but the various existing injury triage methods need further confirmation. This study aims to assess the accuracy of several injury triage methods, namely, the Simple Triage and Rapid Treatment (START) technique; CareFlight Injury Triage (CareFlight); Rapid Emergency Medicine Score (REMS); Triage Revised Trauma Score (T-RTS) and Triage Early Warning Score (TEWS), based on their effects on earthquake injury patients.

DESIGN

Data in the Huaxi Earthquake Casualty Database were analysed retrospectively.

SETTING

This study was conducted in China.

PARTICIPANTS

Data on 29 523 earthquake casualties were separately evaluated using the START technique, CareFlight, REMS, T-RTS and TEWS, with these being the five types of injury triage studied.

PRIMARY OUTCOME MEASURE

The receiver operating characteristic (ROC) curves for the five injury triages were calculated based on hospital deaths, injury severity scores greater than 15 points, and whether casualties stayed in the intensive care unit.

RESULTS

The ROC curve areas of the START technique, CareFlight, REMS, T-RTS and TEWS were 0.750, 0.737, 0.835, 0.736 and 0.797, respectively. Among the five injury triages, the most accurate in predicting hospital deaths was REMS, with an average area under the curve (AUC) of 0.835, with this due to the inclusion of more evaluation indicators.

CONCLUSION

All methods had an effect on the triage of earthquake mass casualties. Among them, the REMS injury triage method had the largest AUC of the five triage methods. Except for REMS, no obvious difference was found in the effect of the other four injury triage methods.