A machine-learning prediction model to identify risk of firearm injury using electronic health records data.

IMPORTANCE: Firearm injuries constitute a public health crisis. At the healthcare encounter level, they are, however, rare events. OBJECTIVE: To develop a predictive model to identify healthcare encounters of adult patients at increased risk of firearm injury to target screening and prevention efforts. MATERIALS AND METHODS: Electronic health records data from Kaiser Permanente Southern California (KPSC) were used to identify healthcare encounters of patients with fatal and non-fatal firearm injuries, as well as healthcare visits of a sample of matched controls during 2010-2018. More than 170 predictors, including diagnoses, healthcare utilization, and neighborhood characteristics were identified. Extreme gradient boosting (XGBoost) and a split sample design were used to train and test a model that predicted risk of firearm injury within the next 3 years at the encounter level. RESULTS: A total of 3879 firearm injuries were identified among 5 288 529 KPSC adult members. Prevalence at the healthcare encounter level was 0.01%. The 15 most important predictors included demographics, healthcare utilization, and neighborhood-level socio-economic factors. The sensitivity and specificity of the final model were 0.83 and 0.56, respectively. A very high-risk group (top 1% of predicted risk) yielded a positive predictive value of 0.14% and sensitivity of 13%. This high-risk group potentially reduces screening burden by a factor of 11.7, compared to universal screening. Results for alternative probability cutoffs are presented. DISCUSSION: Our model can support more targeted screening in healthcare settings, resulting in improved efficiency of firearm injury risk assessment and prevention efforts.

Is the Run, Hide, Fight Concept Effective in Improving Hospital Response to Shooting Incidents? A Systematic Review.

The recent rise of active shootings calls for adequate preparation. Currently, the "Run, Hide, Fight" concept is widely accepted and adopted by many hospitals nationwide. Unfortunately, the appropriateness of this concept in hospitals is uncertain due to lack of data. To understand the "Run, Hide, Fight" concept application in hospitals, a review of currently available data is needed. A systematic review was done focusing on the "Run, Hide, Fight" concept using multiple databases from the past 12 years. The PRISMA flow diagram was used to systematically select the articles based on specific inclusion and exclusion criteria. The measurements were subjective evaluations and survival probabilities post-concept. One agent-based modeling study suggested a high survival probability in non-medical settings. However, there is a paucity of data supporting its effectiveness and applicability in hospitals. Literature suggests a better suitable concept, the "Secure, Preserve, Fight" concept, as a response protocol to active shootings in hospitals. The effectiveness of the "Run, Hide, Fight" concept in hospitals is questionable. The "Secure, Preserve, Fight" concept was found to be designed more specifically for hospitals and closes the gaps on the flaws in the "Run, Hide, Fight" concept.

Video-Assisted Ventral Bulla Osteotomy to Remove a Bullet Foreign Body in a Cat.

A 7 yr old castrated male domestic shorthair presented for assessment of a chronic left head tilt, losses of balance, and positional nystagmus. A computed tomographic scan of the head revealed several fragments of a metallic foreign body in the left tympanic cavity. The foreign material was removed under endoscopic assistance through a minimally invasive ventral bulla osteotomy. No complications were noted during the immediate postoperative period. Follow-up 5 mo after surgery revealed complete resolution of the neurological signs with no evidence of recurrence. Foreign bodies associated with middle ear infection have not been previously reported in the cat. They should now be included in the differential diagnosis of vestibular disease. Endoscopic-assisted foreign body removal in the middle ear seems to be a safe and efficient way to retrieve small foreign bodies in bullae in cats.

Introduction of the modern 3d modeling method into the theory and practice of forensic medicine ballistics, caused by gunshot wounds inflicted by firearms with 9mm caliber ammunition.

OBJECTIVE: Aim: To explore the capabilities of the modern 3D modeling method for various elements of gunshot wounds caused by 9 mm caliber bullets, intending to integrate these findings into the theory and practice of forensic medicine. PATIENTS AND METHODS: Materials and Methods: The research began with a series of experimental shots, during which the morphological features were examined through their 3D spatial reconstruction. The entire series of experimental shots was conducted using an automatic pistol IZH 70-01 equipped with 9.0 mm caliber bullets. The ballistic clay Roma Plastilina No.1, manufactured in the USA, was utilized as a material for conducting standard ballistic tests according to the standards of the NIJ (National Institute of Justice) and HOSDB (Home Office Scientific Development Branch). RESULTS: Results: The research was continued during the performance of forensic examinations involving actual cases of gunshot injuries. The dimensions of individual elements of the wound channel were measured in both experimental and expert cases using conventional measuring tools, as well as after their 3D modeling, utilizing graphic editors such as "Agisoft Photoscan" and "3ds max". CONCLUSION: Conclusions: In the course of creating and studying experimental and expert 3D models, the dimensions of individual morphological elements of the wound channel were recorded with an accuracy that exceeded the results obtained through measurements using traditional measurement methods by ten times.

Public Mass Shootings: Counterfactual Trend Analysis of the Federal Assault Weapons Ban.

Background: Assault weapon and large-capacity magazine bans are potential tools for policy makers to prevent public mass shootings. However, the efficacy of these bans is a continual source of debate. In an earlier study, we estimated the impact of the Federal Assault Weapons Ban (FAWB) on the number of public mass shooting events in the United States. This study provides an updated assessment with 3 additional years of firearm surveillance data to characterize the longer-term effects. Objective: This study aims to estimate the impact of the FAWB on trends in public mass shootings from 1966 to 2022. Methods: We used linear regression to estimate the impact of the FAWB on the 4-year simple moving average of annual public mass shootings, defined by events with 4 or more deaths in 24 hours, not including the perpetrator. The study period spans 1966 to 2022. The model includes indicator variables for both the FAWB period (1995-2004) and the period after its removal (2005-2022). These indicators were interacted with a linear time trend. Estimates were controlled for the national homicide rate. After estimation, the model provided counterfactual estimates of public mass shootings if the FAWB was never imposed and if the FAWB remained in place. Results: The overall upward trajectory in the number of public mass shootings substantially fell while the FAWB was in place. These trends are specific to events in which the perpetrator used an assault weapon or large-capacity magazine. Point estimates suggest the FAWB prevented up to 5 public mass shootings while the ban was active. A continuation of the FAWB and large-capacity magazine ban would have prevented up to 38 public mass shootings, but the CIs become wider as time moves further away from the period of the FAWB. Conclusions: The FAWB, which included a ban on large-capacity magazines, was associated with fewer public mass shooting events, fatalities, and nonfatal gun injuries. Gun control legislation is an important public health tool in the prevention of public mass shootings.

Organic and inorganic gunshot residues on the hands, forearms, face, and nostrils of shooters 30 min after a discharge.

During the investigation of firearm-related incidents, gunshot residues (GSR) can be collected on the scene and individuals (e.g., shooters or bystanders). Their analysis can give valuable information for the reconstruction of the events. Since GSR collection on persons of interest generally occurs a few minutes to hours after discharge, knowledge is needed to understand how organic (O), and inorganic (I) residues are transferred and persist. In this research, the quantities of OGSR and IGSR were assessed on the right and left hands, forearms, face, and nostrils of four shooters. Specimens were collected immediately before the discharge (shooter's blank specimens) and shortly after (30 min) using carbon adhesive stubs. Organic compounds were first extracted from the collection device and analysed using ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Subsequently, IGSR particles were detected on the same stub using scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (SEM/EDS). Shooter's blank specimen analysis revealed background contamination of both O and IGSR in the shooter's environment, predominantly attributed to the presence of an indoor shooting range. However, the background quantities generally remained below the associated 30-minute specimen. Thirty minutes after a discharge, higher quantities were generally detected on the shooter's right and left hands than on other collection regions for both GSR types. Forearms and face emerged as interesting collection alternatives, especially in cases where a person of interest may have washed their hands in the interval between the discharge and collection. In contrast, very low amounts of GSR were detected in the nostrils. Furthermore, the results indicated that OGSR and IGSR have different transfer and persistence mechanisms.

Comparison of In-Hospital Mortality and Neurosurgical Intervention Between Intracranial Gunshot Wounds Arising From Long Guns and Handguns: A Propensity Score Matched Study.

BACKGROUND AND OBJECTIVES: Patients with intracranial gunshot wounds (IC-GSWs) often present with severe neurological injuries requiring prompt neurological evaluation. Neurosurgical intervention is reserved for those with reasonable chances of survival. Handguns and long guns, such as shotguns and rifles, have differing mechanisms of injury which may influence surgical candidacy and outcomes. This study aims to compare rates and types of neurosurgical intervention and inpatient outcomes in patients with IC-GSWs handguns and long guns. METHODS: The National Trauma Data Bank was retrospectively queried for patients with IC-GSWs from 2017 to 2019. Patients with long gun IC-GSWs were propensity score matched with those with handgun IC-GSWs based on patient demographics, comorbidities, insurance status, injury extent and severity, and hospital trauma level. Group differences were compared using Student's t-tests and Pearson's χ2 tests, and multivariable logistic regression was used to identify predictors of in-hospital mortality. RESULTS: Overall, patients in the long gun group were more likely to undergo neurosurgical intervention (21% vs 17%, P = .02). Following propensity score matching, the long gun group had lower rates of in-hospital mortality (35% vs 43%, P < .01), lower rates of cardiac arrest (5% vs 8%, P = .02), and lower rates of reoperation (0% vs 2%, P = .02) than the handgun group. In multivariable regression, independent predictors of survival included long gun IC-GSWs (odds ratio [OR] 0.65, CI 0.52-0.83), neurosurgical foreign body removal (OR 0.44, CI 0.33-0.58), intracranial debridement (OR 0.47, 0.33-0.67), and craniectomy (OR 0.46, CI 0.34-0.63). CONCLUSION: Patients with IC-GSWs present to the hospital with severe neurological injury. Neurosurgical intervention was independently associated with decreased mortality. After matching, patients with long gun IC-GSWs experienced lower in-hospital mortality rates compared with those from handguns. This study suggests that patients suffering from long gun IC-GSW may respond particularly well to neurosurgical intervention and firearm type should be considered when determining neurosurgical candidacy.

Shotgun Bean Bag Projectiles Causing Open Fractures and Retained Radiolucent Foreign Bodies: A Report of 2 Cases.

CASE: Bean bag projectiles (BBPs) are less lethal munition composed of a cloth bag filled with lead pellets and marking powder housed in a plastic casing fired from a 12-gauge shot gun. Two patients sustained penetrating BBP injuries that resulted in open fractures and retained BBP. Patient clothing and all BBP components were found deep in the wounds with marking powder surrounding fracture edges. Both patients healed without infection. CONCLUSION: Surgical exploration of penetrating BBP injuries is recommended to remove marking powder, fabric, plastic, and potentially other forms of contamination. Fracture stabilization should adhere to existing guidelines pertaining to open contaminated wound conditions.

Management of antimicrobial therapy in emergency department admissions and hospitalizations for firearm injuries: A single-center experience.

BACKGROUND: Firearm injuries (FI) remain a significant cause of morbidity and mortality globally. Antibiotic use, supported by guideline recommendations for preventing post-injury infections in FI cases, encounters uncertainties regarding the selection of anti-microbial agents and associated outcomes. This study aimed to investigate the relationship between Injury Severity Scores (ISS) for FI cases presented to the emergency department. METHODS: We empirically revised antimicrobial treatment protocols based on culture results and mortality rates. In the study, 164 firearm injury cases, admitted to the emergency department in 2022 and subsequently hospitalized in clinics and intensive care units (ICU), were evaluated. Cases included in the study were categorized into four groups based on ISS: mild, moderate, severe, and profound injury severity. The study compared the timing of hospital presentation following the injury, hospital length of stay, tissue or blood culture positivity, empirical treatment administered, antimicrobial revision based on culture results, need for ICU admission, mortality status, and ISS among the cases. Data were analyzed using IBM SPSS Statistics 22.0 (SPSS Inc., Chicago, IL). Variables in trauma patients were compared among various groups using Pearson Chi-Square tests. Binary logistic regression tests were performed to identify independent risk factors. A significance level of p<0.05 was considered statistically significant. RESULTS: The study included 164 patients, all of whom were male. The mean age was calculated as 28.9±4.51 years. The average hospital length of stay was 25.54±21.81 days. Eighty-three patients (50.6%) required intensive care. Tissue cultures were obtained from 79 patients (48%). Bacterial growth was observed in 45 of these 79 patients (57%). The appropriate empirical antibiotic treatment rate, assessed among patients who received empirical treatment followed by culture-based antibiotic sensitivity testing, was 48.9%. It was observed that empirical antibiotic regimens were appropriate in 80% of cases in the mild group and 16.7% in the profound severe group (p=0.005). Our study compared the relationship between hospitalization duration and ISS groups. It was observed that hospitalization duration was significantly shorter in the mild group compared to the other groups (p=0.003, p=0.000, p=0.000). It was also observed that the need for ICU admission was higher in groups with higher ISS, indicating a correlation between higher ISS and increased ICU requirements (p=0.000). CONCLUSION: In conclusion, for cases of firearm injuries, we believe empirical antimicrobial therapy should be initiated with narrow-spectrum agents such as beta-lactam + beta-lactamase inhibitor or third-generation cephalosporin + nitroimidazole in the mild group, considering the lack of Pseudomonal activity.

Long-term results of treatment of Gustilo-Anderson type 3A-B tibia fractures due to combat-related high-energy ballistic injuries treated with external circular fixator: Experience of the Military Medical Academy.

OBJECTIVES: The aim of this study was to evaluate the longterm outcomes of open tibia fractures treated using the Ilizarov external circular fixation (ECF) technique in the Military Medical Academy. PATIENTS AND METHODS: Between January 1992 and December 2011, a total of 134 male military personnel (median age: 22.5 years; range, 18 to 36 years) with Gustilo-Anderson type 3 open tibia fractures treated with ECF were retrospectively analyzed. All patients underwent multiple surgeries and eventually Ilizarov fixation surgery. The radiological and functional outcomes were evaluated using the Association for the Study and Application of Methods of Ilizarov (ASAMI) criteria, and complications were noted. RESULTS: The median follow-up was 17.7 (range, 10 to 29) years. The median time to union was 4.7 (range, 3 to 8) months. All frames were removed from the limb, when union was observed. No re-fracture, limb length discrepancy more than 2.5 cm, or below-knee amputation after Ilizarov treatment was seen in any patient. Chronic osteomyelitis was observed at in 40% (n=54) of the patients at a median time ranging from 17 to 148 months. The overall ASAMI bone scores were excellent in 40 (30%), good in 20 (15%), fair in 20 (15%), and poor in 54 (40%) patients with osteomyelitis. The ASAMI functional scores were excellent in 40 (30%), good in 40 (30%), and fair in 54 patients (40%). No poor score was observed. Minor pin site infections were observed in 63 patients (47%). CONCLUSION: Our long-term study results showed that all patients returned to their social life and were mobilized without support after treatment with the use of Ilizarov ECF method of open tibia fractures caused by high-energy ballistic injuries. However, complications such as pin tract infections and osteomyelitis after several years must be kept in mind in the treatment of comminuted bone fractures caused by firearms and ballistic missiles injuries.

Preinjury and Event-Related Characteristics of Pediatric Firearm Injuries: The American College of Surgeons Firearm Study, United States, March 2021‒February 2022.

Objectives. To assess differences in contextual factors by intent among pediatric firearm injury patients and determine factors associated with data missingness. Methods. We retrospectively queried the American College of Surgeons Firearm Study database (March 1, 2021-February 28, 2022) for patients aged 18 years or younger. We stratified preinjury, firearm-related, and event-related factors by intent and compared them by using Fisher exact, χ2, or 1-way analysis of variance testing. Secondary analysis estimated the adjusted odds of missingness by using generalized linear modeling with binominal logit link. Results. Among 17 395 patients, 2974 (17.1%) were aged 18 years or younger; 1966 (66.1%) were injured by assault, 579 (19.5%) unintentionally, and 76 (2.6%) by self-inflicted means. Most contextual factors differed by intent, including proportion of youths with previous adverse childhood experiences, mental illness, and violent assaults or injury, firearm type and access, perpetrator relationship, and injury location. In adjusted analyses, age, trauma center designation, intent, and admission status were associated with missingness. Conclusions. Contextual factors related to pediatric firearm injury vary by intent. Specific predictors associated with missingness may inform improved future data collection. Public Health Implications. Contextual factors related to pediatric firearm injury can be obtained in a systematic manner nationally to inform targeted interventions. (Am J Public Health. 2024;114(10):1097-1109. https://doi.org/10.2105/AJPH.2024.307754).

Project Safe Guard: Evaluating a Lethal Means Safety Intervention to Reduce Firearm Suicide in the National Guard.

INTRODUCTION: The purpose of this paper is to examine a scalable secure firearm storage intervention in the U.S. National Guard (NG) in preventing firearm injury and suicide. A study among firearm-owning members of the Mississippi NG testing Project Safe Guard (PSG), a 10 to 15 min lethal means counseling intervention, found that PSG increased self-reported secure firearm storage practices. Here, we sought to examine a "real world" rollout of a modified PSG program in the NG in which NG members were trained to understand the importance of lethal means safety and to deliver PSG to Guardsmen peers within their units. MATERIALS AND METHODS: The PSG team collaborated with the NG to identify 4 states for the rollout; for each state, the NG was responsible for identifying key personnel ("facilitators") who would receive the training. Team members provided in-person training at 5 locations across 4 states (AZ, GA, IA, and NV) from January to April 2023. Attendees were provided with combination trigger locks or cable locks and evaluation instructions. Questionnaires were administered to training attendees via REDCap at pre-training and post-training. We conducted descriptive and comparison statistics of questionnaire data. RESULTS: A total of 186 facilitators were trained at 5 in-person training locations across 4 states (AZ, GA, IA, and NV) from January to April 2023; data collection concluded in August 2023. There were 137 pre-training responses (74% pre-survey response rate) and 88 post-training responses (64% response rate from those who took the pre-training survey). Findings demonstrate increases in self-reported knowledge, attitudes, and beliefs regarding firearm injury and suicide and a reported desire to store personal firearms more securely. CONCLUSION: The adapted version of PSG shows promise as a relevant and acceptable intervention among Guardsmen to enhance knowledge and attitudes regarding firearm suicide, increase secure firearm storage practices, and normalize conversations about firearm suicide prevention among peers. This intervention seeks to frame firearm suicide prevention within a culture of safety, complementary to the existing prevention methods and training within the NG.

Deadly cerebral ischemia due to carotid stenosis following a facial shot with a pellet gun: An autopsy case report.

INTRODUCTION: Facial gunshot wounds have devastating functional and aesthetic consequences for the patient. If associated with penetrating craniocerebral injuries, the prognosis is rather compromised even with appropriate medical and surgical treatment. Chop-off injuries with penetrating wounds constitute a challenging situation for the facial reconstructive surgeon in facial trauma. OBSERVATION: This case involved a 49-year-old man who sustained an accidental facial shot from a pellet gun. Radiological and clinical investigations revealed complex ballistic trauma to the maxillofacial region, with projectiles reaching the base of the skull. One of the projectiles migrated via the carotid canal towards a cerebral artery, leading to obstruction of the artery with cerebral infarction. An autopsy was performed which evaluated that the shooting distance was compatible with a long distance, causing the dispersion of lead grains with the absence of a wad inside the trauma site. CONCLUSION: In some cases of facial gunshot wounds, despite a complex and extensive lesion assessment, death may occur due to a neurological complication rather than sustaining hemodynamic shock, depending on the trajectory of the projectiles.

Epidemiology of civilian's gunshot wound injuries admitted to intensive care unit: A retrospective, multi-center study.

BACKGROUND: Few studies investigated the outcome of patients admitted to intensive care unit (ICU) for gunshot wounds (GSW). The purpose of this study was to determine the 28-day mortality, and to analyze the impact of variables on the mortality of patients admitted to ICU with GSW in four French University Hospitals level-1 regional trauma centers. METHOD: All medical files of adult patients (above fifteen years old) admitted to four French University Hospitals level-1 regional trauma centers for GSW were retrospectively analyzed from January 1st 2015 to June 30th 2021. The primary aim was to determine 28-day death rate of patients admitted in ICU for GSW. The secondary aim was to describe biological parameters, injuries and management of patients admitted to our ICUs, and to identify the variables associated with the 28-day mortality rate. A multivariate analysis allowed determining independent mortality factors. A Kaplan-Meier analysis compared mortality according to head injury. RESULTS: Among 17,262 patients screened, 173 (1 %) were admitted for GSW and 162 were analyzed. The 28-day mortality rate was 24.7 %. 77.5 % of deaths occurred within the first 48 h after ICU admission, and 87.5 % of deaths within three days of ICU admission. The 28-day death rate of patients with head injury was significantly higher as compared to patients without head injury (p < 0.001). Out of forty deaths, twenty-three (57.5 %) were due to head injury, and nine (22.5 %) were due to bleeding. The mechanisms were assault (45.1 %), suicide (34.6 %), accident (4.9 %) and unidentified (15.4 %). In a multivariate analysis, variables associated with the 28-day death rate were age, pre-hospital Glasgow coma score, and Injury Severity Score. CONCLUSION: GSW represented 1 % of ICU admission. The 28-day mortality rate was 24.7 %. 77.5 % of deaths occurred within the first 48 h due to head injuries and bleeding. Head injuries were associated with significantly higher mortality rate.

Household Firearm Ownership and Firearm Mortality.

Importance: Causal associations between household firearm ownership rates (HFRs) and firearm mortality rates are not well understood. Objective: To assess the population-level temporal sequencing of firearm death rates and HFRs. Design, Setting, and Participants: This cohort study used autoregressive cross-lagged models to analyze HFRs, firearm suicide rates, and firearm homicide rates in the US from 1990 to 2018. The suicide analyses included 16 demographic subgroups of adults, defined by study year, state, sex, race and ethnicity, marital status, and urbanicity. The homicide analyses consisted of adult subgroups living in urban or rural areas. Data analysis was conducted from March to December 2023. Exposures: Firearm mortality rates and HFRs. Main Outcomes and Measures: Firearm homicide and suicide rates with HFRs as the exposure, and HFR with mortality as the exposure. Results: A total of 10 416 observations of 16 demographic subgroups by state and 2-year periods were included in the suicide analyses, while 1302 observations from 2 demographic subgroups by state and 2-year period were included in the homicide analysis. At baseline, the mean (SD) rate per 100 000 population across strata was 7.46 (7.21) for firearm suicides and 3.32 (2.13) for firearm homicides. The mean (SD) baseline HFR was 36.9% (20.2%) for firearm suicides and 36.9% (14.8%) for firearm homicides. Higher HFR preceded increases in suicide rates: demographic strata with equal firearm suicide rates but which differ by 18.6 percentage points on HFR (1 SD) would be expected to have firearm suicide rates that diverged by 0.19 (95% CI, 0.15-0.23) deaths per 100 000 population per period. With these differences accumulated over 8 years, firearm suicide rates in subgroups with the highest decile HFR would be expected to have 1.93 (95% CI, 1.64-2.36) more suicides per 100 000 population than strata with lowest decile HFR, a difference of 25.7% of the overall firearm suicide rate in 2018 and 2019. Firearm suicide rates had a smaller magnitude of association with subsequent changes in HFR: strata with equal HFRs but which differ by 1 SD in firearm suicide rates had minimal subsequent change in HFRs (-0.02 [95% CI, -0.04 to 0.01] percentage points). A 1-SD difference in HFRs was associated with little difference in next-period overall firearm homicides rates (0.03 [95% CI, -0.02 to 0.08] per 100 000 population), but a 1-SD difference in homicide rates was associated with a decrease in HFR (-0.09 [95% CI, -0.16 to -0.04] percentage points). Conclusions and Relevance: This cohort study found an association between high HFRs and subsequent increases in rates of firearm suicide. In contrast, higher firearm homicide rates preceded decreases in HFRs. By demonstrating the temporal sequencing of firearm ownership and mortality, this study may help to rule out some theories of why gun ownership and firearm mortality are associated at the population level.