Small Hemothoraces Not Drained on Admission: Initial Volume Predicts Need for Intervention.

BACKGROUND: Unlike large hemothoraces (HTX), small HTX after blunt trauma may be observed without drainage. We aimed to study if there were risk factors that would predict the need for intervention in initially observed small HTX. METHODS: A retrospective review of patients with blunt traumatic HTX from 2016 to 2022 was performed. Patients with small HTX (pleural fluid volume <400 mL on admission chest computerized tomography [CT]) were included. Patients were considered as being "initially observed" if there was no intervention for the HTX within 48 hours after admission. Primary outcome was any HTX-related intervention (open, thoracoscopic or percutaneous procedures) occurring after 48 hours and up to 6 months after injury. Univariable and multivariable statistical analyses were employed. A P-value of <.05 was considered significant. RESULTS: Of 335 patients with HTX, 188 (59.6%) met inclusion criteria. Median (interquartile range) HTX volume was 90 (36-134) ml. One hundred and twenty-seven (68%) were initially observed. Of these, 31 (24%) had the primary outcome. These patients had a larger HTX volume (median, 129 vs 68 mL, P = .0001), and number of rib fractures (median, 7 vs 4, P = .0002) compared to those without the primary outcome. Chest-related readmission occurred in 8 (6%) with a median of 20 days from injury. Of these, 7 required an HTX-related intervention. Logistic regression analysis found that both the number of rib fractures and HTX volume independently predicted the primary outcome. CONCLUSION: For small HTX initially observed, number of rib fractures and initial volume predicted delayed HTX-related intervention.

Opioid Use in Pelvic Fractures: The Impact of Opioid Prescribing Laws in Pennsylvania.

Pennsylvania's Prescription Drug Monitoring Program (PDMP) was established in 2016, but its impact on opioid use for pelvic fractures is understudied. We compared opioid use in 277 pelvic fracture cases between two periods: 2015-2017 (T1) and 2018-2020 (T2). Outcomes included daily inpatient morphine milligram equivalents (MME), long-term opioid use (LOU) 60-90 days post-discharge, and intermediate-term opioid use (IOU) 30-60 days post-discharge. T1 and T2 had comparable baseline characteristics. T2 was associated with a decrease in average daily inpatient MME (58.6 vs 78.5, P = .02), particularly in younger patients. Regression analyses showed age and Injury Severity Score (ISS) were significant predictors for daily inpatient MME, while time period was not. Geriatric patients in T2 had significantly decreased IOU (30% vs 9%, P = .05). Pelvic fracture type and daily MME predicted IOU, while pelvic fracture type predicted LOU. This study suggests a modest impact of these laws, but further study is needed.

Hypotension in the Emergency Department and Contrast Extravasation on Computerized Tomography Predict Blood Transfusion in Low-Energy Pelvic Fractures.

INTRODUCTION: Although low-energy pelvic fractures seldom present with significant hemorrhage, early recognition of at-risk patients is essential. We aimed to identify predictors of transfusion requirements in this cohort. METHODS: A 7-y retrospective chart review was performed. Low-energy mechanism was defined as falls of ≤5 feet. Fracture pattern was classified using the Orthopedic Trauma Association/Arbeitsgemeinschaft für Osteosynthesefragen system as A, B, or C. Primary outcome was transfusion of ≥2 units of packed red blood cells in the first 48 h. Univariable analysis and logistic regression analysis were performed. A P value ≤0.05 was considered significant. RESULTS: Five hundred forty six patients were included with median (interquartile range) age of 86 (79-91) and median (interquartile range) Injury Severity Score of 5 (4-8). Five hundred forty one (99%) had type A fractures. Twenty six (5%) had the primary outcome and 17 (3%) died. Logistic regression found that systolic blood pressure <100 mmHg at any time in the Emergency Department, Injury Severity Score, and pelvic angiography were predictors of the primary outcome. Seventeen percent of those who had the primary outcome died compared with 2% who did not (P = 0.0004). Three hundred sixty four (67%) received intravenous contrast for computerized tomography scans and of these, 44 (12%) had contrast extravasation (CE). CE was associated with the primary outcome but not mortality. CONCLUSIONS: Hypotension at any time in the Emergency Department and CE on computerized tomography predicted transfusion of ≥2 units packed red blood cells in the first 48 h in patients with low-energy pelvic fractures.

Body Mass Index Does Not Predict Injury Pattern or Outcome After Motorcycle Crash.

INTRODUCTION: The obesity epidemic plagues the United States, affecting approximately 42% of the population. The relationship of obesity with injury severity and outcomes has been poorly studied among motorcycle collisions (MCC). This study aimed to compare injury severity, mortality, injury regions, and hospital and intensive care unit length of stay (LOS) between obese and normal-weight MCC patients. METHODS: Trauma registries from three Pennsylvania Level 1 trauma centers were queried for adult MCC patients (January 1, 2016, and December 31, 2020). Obesity was defined as adult patients with body mass index ≥ 30 kg/m2 and normal weight was defined as body mass index < 30 kg/m2 but > 18.5 kg/m2. Demographics and injury characteristics including injury severity score (ISS), abbreviated injury score, mortality, transfusions and LOS were compared. P ≤ 0.05 was considered significant. RESULTS: One thousand one hundred sixty-four patients met the inclusion criteria: 40% obese (n = 463) and 60% nonobese (n = 701). Comparison of ISS demonstrated no statistically significant difference between obese and normal-weight patients with median ISS (interquartile range) 9 (5-14) versus 9 (5-14), respectively (P = 0.29). Obese patients were older with median age 45 (32-55) y versus 38 (26-54) y, respectively (P < 0.01). Comorbidities were equally distributed among both groups except for the incidence of hypertension (30 versus 13.8%, P < 0.01) and diabetes (11 versus 4.4%, P < 0.01). There was no statistically significant difference in Trauma Injury Severity Score or abbreviated injury score. Hospital LOS, intensive care unit LOS, and 30-day mortality among both groups were similar. CONCLUSIONS: Obese patients experiencing MCC had no differences in distribution of injury, mortality, or injury severity, mortality, injury regions, and hospital compared to normal-weight adults. Our study differs from current data that obese motorcycle drivers may have different injury characteristics and increased LOS.

Geriatric Motorcycle-Related Outcomes: A Pennsylvania Multicenter Study.

INTRODUCTION: Geriatric patients (GeP) often experience increased morbidity and mortality following traumatic insult and as a result, require more specialized care due to lower physiologic reserve and underlying medical comorbidities. Motorcycle injuries (MCCI) occur across all age groups; however, no large-scale studies evaluating outcomes of GeP exist for this particular subset of patients. Data thus far are limited to elderly participation in recreational activities such as water and alpine skiing, snowboarding, equestrian, snowmobiles, bicycles, and all-terrain vehicles. We hypothesized that GeP with MCCI will have a higher rate of mortality when compared with their younger counterparts despite increased helmet usage. METHODS: We performed a multicenter retrospective review of MCCI patients at three Pennsylvania level I trauma centers from January 2016 to December 2020. Data were extracted from each institution's electronic medical records and trauma registry. GeP were defined as patients aged more than or equal to 65 y. The primary outcome was mortality. Secondary outcomes included ventilator days; hospital, intensive care unit, and intermediate unit length of stays; complications; and helmet use. 3:1 nongeriatric patients (NGeP) to GeP propensity score matching (PSM) was based on sex, abbreviated injury scale (AIS), and injury severity score (ISS). P ≤ 0.05 was considered significant. RESULTS: One thousand five hundred thirty eight patients were included (GeP: 7% [n = 113]; NGP: 93% [n = 1425]). Prior to PSM, GeP had higher median Charlson Comorbidity Index (GeP: 3.0 versus NGeP: 0.0; P ≤ 0.001) and greater helmet usage (GeP: 73.5% versus NGeP: 54.6%; P = 0.001). There was a statistically significant difference between age cohorts in terms of ISS (GeP: 10.0 versus NGeP: 6.0, P = 0.43). There was no significant difference for any AIS body region. Mortality rates were similar between groups (GeP: 1.7% versus NGeP: 2.6%; P = 0.99). After PSM matching for sex, AIS, and ISS, GeP had significantly more comorbidities than NGeP (P ≤ 0.05). There was no difference in trauma bay interventions or complications between cohorts. Mortality rates were similar (GeP: 1.8% versus NGeP: 3.2%; P = 0.417). Differences in ventilator days as well as intensive care unit length of stay, intermediate unit length of stay, and hospital length of stay were negligible. Helmet usage between groups were similar (GeP: 64.5% versus NGeP: 66.8%; P = 0.649). CONCLUSIONS: After matching for sex, ISS, and AIS, age more than 65 y was not associated with increased mortality following MCCI. There was also no significant difference in helmet use between groups. Further studies are needed to investigate the effects of other potential risk factors in the aging patient, such as frailty and anticoagulation use, before any recommendations regarding management of motorcycle-related injuries in GeP can be made.

Quantitative computed tomography analysis of body composition changes in paediatric patients with acute lymphoblastic leukaemia.

Children with acute lymphoblastic leukaemia (ALL) are at risk for obesity and cardiometabolic diseases. To gain insight into body composition changes among children with ALL, we assessed quantitative computed tomography (QCT) data for specific body compartments (subcutaneous adipose tissue [SAT], visceral adipose tissue [VAT], total adipose tissue [TAT], lean tissue [LT], LT/TAT and VAT/SAT at lumbar vertebrae L1 and L2) at diagnosis and at off-therapy for 189 children with ALL and evaluated associations between body mass index (BMI) Z-score and clinical characteristics. BMI Z-score correlated positively with SAT, VAT and TAT and negatively with LT/TAT and VAT/SAT. At off-therapy, BMI Z-score, SAT, VAT and TAT values were higher than at diagnosis, but LT, LT/TAT and VAT/SAT were lower. Patients aged ≥10 years at diagnosis had higher SAT, VAT and TAT and lower LT and LT/TAT than patients aged 2.0-9.9 years. Female patients had lower LT and LT/TAT than male patients. Black patients had less VAT than White patients. QCT analysis showed increases in adipose tissue and decreases in LT during ALL therapy when BMI Z-scores increased. Early dietary and physical therapy interventions should be considered, particularly for patients at risk for obesity.

Early Pharmacologic Therapy in Patients With Blunt Cerebrovascular Injury and TBI: Is it Safe and Effective? An EAST Multicenter Study.

BACKGROUND: Blunt cerebrovascular injury (BCVI) with concurrent traumatic brain injury (TBI) presents increased risk of both ischemic stroke and bleeding. This study investigated the safety and survival benefit of BCVI treatment (antithrombotic and/or anticoagulant therapy) in this population. We hypothesized that treatment would be associated with fewer and later strokes in patients with BCVI and TBI without increasing bleeding complications. METHODS: Patients with head AIS >0 were selected from a database of BCVI patients previously obtained for an observational trial. A Kaplan-Meier analysis compared stroke survival in patients who received BCVI treatment to those who did not. Logistic regression was used to evaluate for confounding variables. RESULTS: Of 488 patients, 347 (71.1%) received BCVI treatment and 141 (28.9%) did not. BCVI treatment was given at a median of 31 h post-admission. BCVI treatment was associated with lower stroke rate (4.9% vs 24.1%, P < .001 and longer stroke-free survival (P < .001), but also less severe systemic injury. Logistic regression identified motor GCS and BCVI treatment as the only predictors of stroke. No patients experienced worsening TBI because of treatment. DISCUSSION: Patients with BCVI and TBI who did not receive BCVI treatment had an increased rate of stroke early in their hospital stay, though this effect may be confounded by worse motor deficits and systemic injuries. BCVI treatment within 2-3 days of admission may be safe for patients with mean head AIS of 2.6. Future prospective trials are needed to confirm these findings and determine optimal timing of BCVI treatment in TBI patients with BCVI.

Interpreting Lower Trapezius Musculocutaneous Flap Skin Paddle Perfusion with Indocyanine Green Angiography.

Background: The lower trapezius myocutaneous flap (LTF) is a pedicled flap with clinically significant variability of distal skin flap perfusion. Objective: To compare the incidence of partial flap necrosis before and after the institution of routine intraoperative laser-assisted indocyanine green (ICG) angiography. Methods: This is a retrospective review of all LTF performed between November 2021 and July 2022. The outcomes measured in this study are the distance distal to the inferior border of the trapezius muscle with adequate perfusion, and incidence and degree of partial flap necrosis. Results: Sixteen patients met inclusion criteria with a median age of 64.5 years, and a median defect size of 147 cm2. Most patients (11/16) had undergone previous treatment for malignancy. Before utilizing ICG angiography, 40% (2/5) had partial flap necrosis, whereas after utilizing ICG angiography, 9% (1/11) of patients had partial flap necrosis. Seventy-three percent (8/11) of cases who underwent ICG angiography demonstrated a portion of the skin paddle with inadequate perfusion. The range of skin perfusion distal to the inferior border of the trapezius muscle was 0-7 cm (median, 4). Conclusions: The incidence of partial flap necrosis decreased after institution of routine ICG angiography.

Age-Adjusted Modified Frailty Index: Association With Hip Fracture Discharge Functional Dependence.

INTRODUCTION: Hip fractures are a common traumatic injury that carry significant morbidity and mortality, and prognostication of functional outcome is becoming increasingly salient. Across multiple surgical specialties, the five-item and 11-item Modified Frailty Index (mFI-5 and mFI-11) have been found to be convenient, quick, and sensitive tools for identifying patients at risk for perioperative complications. A prior study described the superiority of an Age-Adjusted Modified Frailty Index (aamFI) for predicting perioperative complications compared to the mFI-5 in an elective hip surgery. We sought to externally validate the aamFI in a multicenter hip fracture cohort and hypothesize that these risk scores would not only predict functional dependence (FD) at discharge, but that the aamFI would outperform the mFI-5 and mFI-11. METHODS: The Pennsylvania Trauma Systems Foundation registry was queried from 2010 to 2020 for CPT codes, ICD-9 and ICD-10 codes pertaining to hip fracture patients. Patients with missing locomotion and transfer mobility data were excluded. FD status was determined by discharge locomotion and transfer mobility scores per existing methodology. Univariable and Multivariable analysis as well as receiver operator characteristic curves were used to evaluate and compare the three indices for prediction of functional status at discharge. P value < 0.05 was considered significant. RESULTS: Twelve thousand seven hundred and forty patients met inclusion criteria (FD: 8183; functional independent 4557). On univariable logistic regression analysis, the mFI-11 (odds ratio [OR] 1.52, 95% confidence interval [CI] 1.47-1.58, P < 0.05), mFI-5 (OR 1.57, 95% CI 1.51-1.63), and aamFI (OR 1.57, 95% CI 1.52-1.62, P < 0.05) were associated with FD. On multivariable logistic regression analysis for predictors of FD, when controlling for age (for the mFI-11 and mFI-5), sex, injury severity score, and admission vitals (systolic blood pressure and respiratory rate), higher mFI-11 and mFI-5 scores independently predicted FD at discharge (OR 1.23, 95% CI 1.18-1.28, P < 0.05 and OR 1.23, 95% CI 1.18-1.29P < 0.05 respectively). Higher aaMFI scores had superior association with functional dependence (OR 1.59, 95% CI 1.54-1.64, P < 0.05). Receiver operator characteristic curves for the mFI-11, mFI-5, and aaMFI showed comparable diagnostic strength (area under curve [AUC] = 0.63 95% CI 0.62-0.64, P < 0.05; AUC = 0.63 95% CI 0.62-0.64, P < 0.05; and AUC = 0.67 95% CI 0.65-0.67, P < 0.05 respectively). CONCLUSIONS: The mFI-11, mFI-5, and aamFI are predictive of functional outcome following hip fracture. By including age, the aamFI retains the ease of use of the mFI-5 while improving its prognostic utility for functional outcome.

Prevalence and Predictors of Long-term Opioid Use After Pelvic Fractures.

BACKGROUND: Opioids are effective in short-term pain treatment; however, their long-term effectiveness is unconfirmed. Many patients are exposed to opioids after pelvic injuries with little known about persistent use afterward. We assessed the prevalence and predictors of long-term opioid use following pelvic fractures. MATERIALS AND METHODS: This retrospective study enrolled 277 patients with acute pelvic fractures over five years. Daily and total morphine milligram equivalents (MME) were calculated. The primary outcome was long-term opioid use (LOU) defined as ongoing opioid use 60-90 days post-discharge. The secondary outcome was intermediate-term opioid use (IOU) defined as ongoing opioid use 30-60 days post-discharge. Univariable and logistic regression analyses were performed. RESULTS: Median (interquartile range) total inpatient opioid MME was 422 (157-1667) with a median daily MME of 69 (26-145). Long-term opioid use occurred in 16%, and IOU occurred in 29%. Univariable analysis found that total and daily inpatient opioid use were each significantly associated with LOU (median MME, 1241 vs 371; median MMEs, 127.7 vs 59.2, respectively) and IOU (median MME, 1140 vs 326; median MMEs, 111.8 vs 57.9, respectively). Logistic regression analysis found daily inpatient MME ≥50 (odds ratio [OR] 3.027, 95% confidence interval [CI] 1.059-8.652]) and pelvic fracture type (Tile B/C) (OR 2.992 [CI 1.324-6.763])were independent predictors of LOU. CONCLUSION: Total and daily inpatient opioid use were significantly associated with LOU and IOU. Patients who received ≥50 MME/inpatient day had a higher likelihood of LOU. This study seeks to inform clinical decisions for pain management to prevent adverse outcomes.

Additively Manufactured Dual-Faced Structured Fabric for Shape-Adaptive Protection.

Fabric-based materials have demonstrated promise for high-performance wearable applications but are currently restricted by their deficient mechanical properties. Here, this work leverages the design freedom offered by additive manufacturing and a novel interlocking pattern to for the first time fabricate a dual-faced chain mail structure consisting of 3D re-entrant unit cells. The flexible structured fabric demonstrates high specific energy absorption and specific strength of up to 1530 J kg-1 and 5900 Nm kg-1 , respectively, together with an excellent recovery ratio of ≈80%, thereby overcoming the strength-recoverability trade-off. The designed dual-faced structured fabric compares favorably against a wide range of materials proposed for wearable applications, attributed to the synergetic strengthening of the energy-absorbing re-entrant unit cells and their unique topological interlocking. This work advocates the combined design of energy-absorbing unit cells and their interlocking to extend the application prospects of fabric-based materials to shape-adaptive protection.

Traumatic Amputation From a Rollover Farming Incident in a 16-Year-Old.

There is very little literature on the overall management of adolescent traumatic amputation, specifically of the lower extremity. We present a case involving an adolescent patient involved in an industrial farm tractor rollover with substantial crush and degloving injuries requiring bilateral lower extremity amputations. The patient was initially assessed and acutely managed in the field before arriving at an adult level 1 trauma center having two right lower extremity tourniquets already applied and a pelvic binder in place. During his hospitalization, he was revised to bilateral above-knee amputations that required multiple debridements prior to being transferred to a pediatric trauma center due to the extent of the soft tissue injury and need for flap coverage. Our adolescent patient presented with an uncommon injury mechanism resulting in significantly mangled lower extremities highlighting the importance of a multidisciplinary approach in all aspects of the patient's prehospital, intrahospital, and posthospital care.

Acute Colonic Pseudo-obstruction: Colonoscopy Versus Neostigmine First?

INTRODUCTION: Neostigmine (NEO) and decompressive colonoscopy (COL) are two efficacious treatment modalities for acute colonic pseudo-obstruction (ACPO). We hypothesize that a COL first strategy is associated with better outcomes compared to a NEO first strategy. METHODS: A single-center retrospective analysis was performed from 2013 to 2020. Patients ≥18 y with a diagnosis of ACPO were included. The outcome was a composite measure of acute operative intervention, 30-day readmission with ACPO, and 30-day ACPO-related mortality. A P-value of ≤ 0.05 indicated statistical significance. RESULTS: Of 910 encounters in 849 patients, 50 (5.5%) episodes of ACPO in 39 patients were identified after exclusion of one patient with colon perforation on presentation. The median (interquartile range) age was 68 (62-84) y. NEO and COL were administered in 21 and 25 episodes, respectively. In 16 (32%) episodes, no NEO or COL was administered. When patients were given NEO first, COL or additional NEO was required in 12/18 (67%) compared with a COL first strategy where a second COL and/or NEO was given in 5/16 (32%) (P = 0.05). Both strategies had similar outcomes (NEO, 4/18 versus COL, 4/16, P = 0.85). Twenty-two (44%) episodes had an early intervention (≤48 h) with NEO and/or COL. There was no difference in outcome between those that received an early intervention and those who did not (5/22 versus 5/28, P = 0.71). CONCLUSIONS: For patients failing conservative measures, a COL first approach was associated with fewer subsequent interventions, but with similar composite outcomes compared to a NEO first approach. Early (≤48 h) intervention with NEO and/or COL was not associated with improved outcomes.

An improved parameterization procedure for NDDO-descendant semi-empirical methods.

CONCEPT: MNDO-based semi-empirical methods in quantum chemistry have found widespread application in the modelling of large and complex systems. A method for the analytic evaluation of first and second derivatives of molecular properties against semi-empirical parameters in MNDO-based NDDO-descendant models is presented, and the resultant parameter Hessian is compared against the approximant currently used in parameterization for the PMx models. METHODS: As a proof of concept, the exact parameter Hessian is employed in a limited reparameterization of MNDO for the elements C, H, N, O and F using 1206 molecules for reference data (heats of formation, ionization energies, dipole moments and reference geometries). The correctness of our MNDO implementation was verified by comparing the calculated molecular properties with the MOPAC program.

Negative Splenic Angiography in Blunt Trauma: Does Embolization Affect Splenic Salvage?

Angioembolization in blunt splenic trauma is used to maximize splenic preservation. Superiority of prophylactic embolization over expectant management in patients with a negative splenic angiography (SA) is debated. We hypothesized that embolization in negative SA would be associated with splenic salvage. Of 83 patients undergoing SA, 30 (36%) had a negative SA. Embolization was performed in 23 (77%). Grade of injury, contrast extravasation (CE) on computed tomography (CT) or embolization were not associated with splenectomy. In 20 patients with either a high-grade injury or CE on CT, 17 (85%) underwent embolization with a failure rate of 24%. In the remaining 10 without high-risk features, 6 underwent embolization with a 0% splenectomy rate. Despite embolization, the failure rate of nonoperative management (NOM) remains significant in those with high-grade injury or CE on CT. A low threshold for early splenectomy after prophylactic embolization is needed.

Distal Pancreatic Necrosis After Splenic Angioembolization.

Pancreatic ischemia with necrosis is an extremely rare complication of splenic angioembolization (SAE). A 48-year-old male with a grade IV blunt splenic injury underwent angiography which demonstrated no active bleeding or pseudoaneurysm. Proximal SAE was performed. One week later, he developed severe sepsis. Repeat CT imaging showed nonperfusion of the distal pancreas, and laparotomy found necrosis of approximately 40% of the pancreas. Distal pancreatectomy and splenectomy were performed. He endured a prolonged hospital course with multiple complications. Clinicians should have a high index of suspicion for ischemic complications after SAE when sepsis develops.

Large Traumatic Lumbar Hernia: A Difficult and Uncommon Problem.

Lumbar hernias are congenital or acquired posterolateral abdominal wall hernias and are located in the superior or inferior lumbar triangle. Traumatic lumbar hernias are rare, and the optimal method to repair these is not well-defined. We present the case of a 59-year-old obese female who presented after a motor vehicle collision with an 8.8 cm traumatic right-sided inferior lumbar hernia and overlying complex abdominal wall laceration. The patient underwent an open repair with retro rectus polypropylene mesh and biologic mesh underlay several months after the abdominal wall wound healed, and the patient lost 60 pounds. The patient recovered well without complications or recurrence at the one-year follow-up. This case demonstrates a complex, open surgical approach to repair a large traumatic lumbar hernia not amenable to laparoscopic repair.

Percutaneous Retrieval of Retained Gallstones.

Laparoscopic cholecystectomy has become the gold standard for patients with gallbladder disease. However, spilled gallstones occur in up to 18% of laparoscopic cholecystectomies, which may result in retained gallstones. Though most do not cause issues, there may be abscess formation from 4 months to 10 years postoperatively. We present a 78-year-old patient who formed a subhepatic abscess 3 months postoperatively from his laparoscopic cholecystectomy secondary to a 1 cm retained gallstone. The abscess was percutaneously drained by interventional radiology (IR), and the stone was subsequently removed by IR using a percutaneous approach. Open and laparoscopic approaches have been previously described for abscess drainage and removal of gallstones. In this case, both the abscess and stone were drained and removed percutaneously by IR. Though this is an uncommon entity, percutaneous decompression can aid in preventing such patients from undergoing additional surgery.

Grade 1 Internal Carotid Artery Blunt Cerebrovascular Injury Persistence Risks Stroke With Current Management: An EAST Multicenter Study.

BACKGROUND: Higher blunt cerebrovascular injury (BCVI) grade and lack of medical therapy are associated with stroke. Knowledge of stroke risk factors specific to individual grades may help tailor BCVI therapy to specific injury characteristics. METHODS: A post-hoc analysis of a 16 center, prospective, observational trial (2018-2020) was performed including grade 1 internal carotid artery (ICA) BCVI. Repeat imaging was considered the second imaging occurrence only. RESULTS: From 145 grade 1 ICA BCVI included, 8 (5.5%) suffered a stroke. Grade 1 ICA BCVI with stroke were more commonly treated with mixed anticoagulation and antiplatelet therapy (75.0% vs 9.6%, P <.001) and less commonly antiplatelet therapy (25.0% vs 82.5%, P = .001) compared to injuries without stroke. Of the 8 grade 1 ICA BCVI with stroke, 4 (50.0%) had stroke after medical therapy was started. In comparing injuries with resolution at repeat imaging to those without, stroke occurred in 7 (15.9%) injuries without resolution and 0 (0%) injuries with resolution (P = .005). At repeat imaging in grade 1 ICA BCVI with stroke, grade of injury was grade 1 in 2 injuries, grade 2 in 3 injuries, grade 3 in 1 injury, and grade 5 in one injury. DISCUSSION: While the stroke rate for grade 1 ICA BCVI is low overall, injury persistence appears to heighten stroke risk. Some strokes occurred despite initiation of medical therapy. Repeat imaging is needed in grade 1 ICA BCVI to evaluate for injury progression or resolution.