Risk Factors for Empyema Following Penetrating Diaphragmatic Injuries

Empyema resulting as a complication of penetrating diaphragmatic injuries is a subject that requires further investigation, and the aim of this study was to determine the risk factors associated with empyema in patients with penetrating trauma. Consecutive adult trauma patients from a level 1 trauma center were searched for penetrating diaphragm injuries. Data were collected on patient demographics, pre-existing conditions, injury type and severity, hospital interventions, in-hospital complications, and outcomes. Patients were stratified by empyema formation and univariant analyses were performed. 164 patients were identified, and 17 patients (10.4%) developed empyema. Empyema was associated with visible abdominal contamination (35.3% vs 15%, P = .04), thoracotomy (35.5% vs 13.6%, P = .03), pneumonia (41.2% vs 14.3%, P = .01), sepsis (35.3% vs 8.8%, P = .006), increased hospital length of stay (25.5 vs 10.1 days, p =<.001), increased intensive care unit length of stay (9.6 vs 4.3 days, P = .01), and decreased in-hospital mortality (0% vs 20.4%, P = .04).

Prehospital Needle Decompression of Suspected Tension Pneumothorax: Outcomes and Consequences

Tension pneumothorax (TPT) identified in the prehospital setting requires prehospital needle decompression (PHND). This study aimed to evaluate complications from PHND when it was performed without meeting clinical criteria. A retrospective review was performed of patients undergoing (PHND) from 2016 through 2022 at a level 1 trauma center. Patient data who received PHND were reviewed. Of 115 patients, 85 did not meet at least one clinical criterion for PHND. The majority of patients in this cohort 76 (89%) required a chest tube and 22 (25%) had an iatrogenic pneumothorax from PHND. 5 patients (6%) were admitted due to iatrogenic PHND. Two vascular injuries in this population were directly due to PHND and required emergency operative repair. This study shows the negative consequences of PHND when performed without clear indications. Several patients underwent unnecessary procedures with significant clinical consequences.

Chest Tube Size Selection: Evaluating Provider Practices, Treatment Efficacy, and Complications in Management of Thoracic Trauma

BACKGROUND

The standard for managing traumatic pneumothorax (PTX), hemothorax (HTX), and hemopneumothorax (HPTX) has historically been large-bore (LB) chest tubes (>20-Fr). Previous studies have shown equal efficacy of small-bore (SB) chest tubes (≤19-Fr) in draining PTX and HTX/HPTX. This study aimed to evaluate provider practice patterns, treatment efficacy, and complications related to the selection of chest tube sizes for patients with thoracic trauma.

METHODS

A retrospective chart review was performed on adult patients who underwent tube thoracostomy for traumatic PTX, HTX, or HPTX at a Level 1 Trauma Center from January 2016 to December 2021. Comparison was made between SB and LB thoracostomy tubes. The primary outcome was indication for chest tube placement based on injury pattern. Secondary outcomes included retained hemothorax, insertion-related complications, and duration of chest tube placement. Univariate and multivariate analyses were performed.

RESULTS

Three hundred and forty-one patients were included and 297 (87.1%) received LB tubes. No significant differences were found between the groups concerning tube failure and insertion-related complications. LB tubes were more frequently placed in patients with penetrating MOI, higher average ISS, and higher average thoracic AIS. Patients who received LB chest tubes experienced a higher incidence of retained HTX.

DISCUSSION

In patients with thoracic trauma, both SB and LB chest tubes may be used for treatment. SB tubes are typically placed in nonemergent situations, and there is apparent provider bias for LB tubes. A future randomized clinical trial is needed to provide additional data on the usage of SB tubes in emergent situations.

Discrepancies in Mass Shootings and Access to Trauma Care Across the United States, 2014-2018

INTRODUCTION

The United States has one of the highest rates of gun violence and mass shootings. Timely medical attention in such events is critical. The objective of this study was to assess geographic disparities in mass shootings and access to trauma centers.

METHODS

Data for all Level I and II trauma centers were extracted from the American College of Surgeons and the Trauma Center Association of America registries. Mass shooting event data (4+ individuals shot at a single event) were taken from the Gun Violence Archive between 2014 and 2018.

RESULTS

A total of 564 trauma centers and 1672 mass shootings were included. Ratios of the number of mass shootings vs trauma centers per state ranged from 0 to 11.0 mass shootings per trauma center. States with the greatest disparity (highest ratio) included Louisiana and New Mexico.

CONCLUSION

States in the southern regions of the US experience the greatest disparity due to a high burden of mass shootings with less access to trauma centers. Interventions are needed to increase access to trauma care and reduce mass shootings in these medically underserved areas.

MultiCenter Study of Intra-Abdominal Abscess Formation After Major Operative Hepatic Trauma

INTRODUCTION

One of the significant complications of operative liver trauma is intra-abdominal abscesses (IAA). The objective of this study was to determine risk factors associated with postoperative IAA in surgical patients with major operative liver trauma.

METHODS

A retrospective multi-institutional study was performed at 13 Level 1 and Level 2 trauma centers from 2012 to 2021. Adult patients with major liver trauma (grade 3 and higher) requiring operative management were enrolled. Univariate and multivariate analyses were performed.

RESULTS

Three hundred seventy-two patients were included with 21.2% (n = 79/372) developing an IAA. No difference was found for age, gender, injury severity score, liver injury grade, and liver resections in patients between the groups (P > 0.05). Penetrating mechanism of injury (odds ratio (OR) 3.42, 95% confidence interval (CI) 1.54-7.57, P = 0.02), intraoperative massive transfusion protocol (OR 2.43, 95% CI 1.23-4.79, P = 0.01), biloma/bile leak (OR 2.14, 95% CI 1.01-4.53, P = 0.04), hospital length of stay (OR 1.04, 95% CI 1.02-1.06, P < 0.001), and additional intra-abdominal injuries (OR 2.27, 95% CI 1.09-4.72, P = 0.03) were independent risk factors for IAA. Intra-abdominal drains, damage control laparotomy, total units of packed red blood cells, number of days with an open abdomen, total abdominal surgeries, and blood loss during surgery were not found to be associated with a higher risk of IAA.

CONCLUSIONS

Patients with penetrating trauma, massive transfusion protocol activation, longer hospital length of stay, and injuries to other intra-abdominal organs were at higher risk for the development of an IAA following operative liver trauma. Results from this study could help to refine existing guidelines for managing complex operative traumatic liver injuries.

PRRSV-2 viral load in critical non-lymphoid tissues is associated with late gestation fetal compromise

The impact of late gestation PRRSV-2 infection is highly variable within a litter, with a subset of fetuses displaying varying degrees of compromise following infection while others remain viable despite significant systemic viral load. To understand the underlying cause of this variation, we examined the susceptibility, distribution and impact of viral infection within non-lymphoid tissues. Samples of brain, heart, kidney, liver, lung, and skeletal muscle were obtained from fetuses of pregnant gilts at gestation day 86, and the presence and distribution of CD163+ cells within each tissue evaluated via immunohistofluorescence. Equivalent samples were collected from phenotypic extremes representing resistant, resilient and susceptible fetuses at 21 days following infection of pregnant gilts with PRRSV-2 at day 86 of gestation. Viral load and its impact in each tissue was evaluated by a combination of qPCR, in vitro viral recovery, and local expression of IFNG and CD163. Resting populations of CD163+ cells were observed in all six non-lymphoid tissues from healthy day 86 fetuses, though the apparent density and the morphology of positive cells varied between tissue. Viral RNA was detected in all six tissues derived from fetuses previously classified as highly infected, and infectious viral particles successfully recovered. Significantly more viral RNA was detected in heart, brain, lung and skeletal muscle of susceptible fetuses, relative to their viable counterparts. Infection was associated with an increase in the expression of CD163 in brain, kidney and lung. In addition, the presence of virus in each tissue coincided with a significant upregulation in the expression of IFNG, but the scale of this response was not associated with fetal susceptibility. Thus, PRRSV-2 is widely distributed across these susceptible non-lymphoid fetal tissues, and fetal outcome is associated with local viral load in critical fetal organs.

Modification of the inflammatory profile of mesenchymal stem cells using different culture conditions

Aim: Mesenchymal stem cells (MSCs) are pluripotent cells with significant therapeutic potential. The objective of this study was to examine the inflammatory profile of MSCs cultured under different conditions. Methods: MSCs were cultured by three strategies: seeding on an extracellular matrix (ECM), spheroids in static culture and spheroids in a bioreactor. Paracrine factors and CD206, a marker of M2 macrophage phenotype, were measured. Results: MSCs grown as spheroids in a bioreactor produced more IL-6 and IL-8 (p < 0.05). Supernatant collected from spheroids under both culture conditions increased the M2 macrophage phenotype almost twofold. Conclusion: Results indicate that the inflammatory profile of the supernatant collected from MSCs can be modified through culture conditions which has impacts for the future of regenerative medicine.

Efficacy and Safety of Whole Blood Transfusion in Non-Trauma Patients

Whole blood (WB) transfusion for trauma patients with severe hemorrhage has demonstrated early successful outcomes compared to conventional component therapy. The objective of this study was to demonstrate WB transfusion in the non-trauma patient. Consecutive adult patients receiving WB transfusion at a single academic institution were reviewed from February 2018 to January 2020. Outcomes measured were mortality and transfusion-related reactions. A total of 237 patients who received WB were identified with 55 (23.2%) non-trauma patients. Eight patients (14.5%) received pre-hospital WB. The most common etiology of non-traumatic hemorrhage was gastrointestinal bleeding (43.6%, n = 24/55). Approximately half of the non-trauma patients (n = 28/55) received component therapy. Transfusion-related events occurred in 3 patients. This study demonstrated that non-trauma patients could receive WB transfusions safely with infrequent transfusion-related events. Future studies should focus on determining if outcomes are improved in non-trauma patients who receive WB transfusions and defining specific transfusion criteria for this population.

Multicenter Study of Perioperative Hepatic Angioembolization as an Adjunct for Management of Major Operative Hepatic Trauma

BACKGROUND

The management of major liver trauma continues to evolve in trauma centers across the US with increasing use of minimally invasive techniques. Data on the outcomes of these procedures remain minimal. The objective of this study was to evaluate patient complications after perioperative hepatic angioembolization as an adjunct to management of major operative liver trauma.

STUDY DESIGN

A retrospective multi-institutional study was performed at 13 level 1 and level 2 trauma centers from 2012 to 2021. Adult patients with major liver trauma (grade 3 and higher) requiring operative management were enrolled. Patients were divided into 2 groups: angioembolization (AE) and no angioembolization (NO AE). Univariate and multivariate analyses were performed.

RESULTS

A total of 442 patients were included with AE performed in 20.4% (n = 90 of 442) of patients. The AE group was associated with higher rates of biloma formation (p = 0.0007), intra-abdominal abscess (p = 0.04), pneumonia (p = 0.006), deep vein thrombosis (p = 0.0004), acute renal failure (p = 0.004), and acute respiratory distress syndrome (p = 0.0003), and it had longer ICU and hospital length of stay (p < 0.0001). On multivariate analysis, the AE had a significantly higher amount intra-abdominal abscess formation (odds ratio 1.9, 95% CI 1.01 to 3.6, p = 0.05).

CONCLUSIONS

This is one of the first multicenter studies comparing AE in specifically operative high-grade liver injuries and found that patients with liver injury that undergo AE in addition to surgery have higher rates of both intra- and extra-abdominal complications. This provides important information that can guide clinical management.

The impact of prehospital whole blood on hemorrhaging trauma patients: A multi-center retrospective study

BACKGROUND

Whole blood (WB) use has become increasingly common in trauma centers across the United States for both in-hospital and prehospital resuscitation. We hypothesize that prehospital WB (pWB) use in trauma patients with suspected hemorrhage will result in improved hemodynamic status and reduced in-hospital blood product requirements.

METHODS

The institutional trauma registries of two academic level I trauma centers were queried for all patients from 2015-2019 who underwent transfusion upon arrival to the trauma bay. Patients who were dead on arrival or had isolated head injuries were excluded. Demographics, injury and shock characteristics, transfusion requirements, including massive transfusion protocol (MTP) (>10 U in 24 hours) and rapid transfusion (CAT3+) and outcomes were compared between pWB and non-pWB patients. Significantly different demographic, injury characteristics and pWB were included in univariate followed by stepwise logistic regression analysis to determine the relationship with shock index (SI). Our primary objective was to determine the relationship between pWB and improved hemodynamics or reduction in blood product utilization.

RESULTS

A total of 171 pWB and 1391 non-pWB patients met inclusion criteria. Prehospital WB patients had a lower median Injury Severity Score (17 vs. 21, p < 0.001) but higher prehospital SI showing greater physiologic disarray. Prehospital WB was associated with improvement in SI (-0.04 vs. 0.05, p = 0.002). Mortality and (LOS) were similar. Prehospital WB patients received fewer packed red blood cells, fresh frozen plasma, and platelets units across their LOS but total units and volumes were similar. Prehospital WB patients had fewer MTPs (22.6% vs. 32.4%, p = 0.01) despite a similar requirement of CAT3+ transfusion upon arrival.

CONCLUSION

Prehospital WB administration is associated with a greater improvement in SI and a reduction in MTP. This study is limited by its lack of power to detect a mortality difference. Prospective randomized controlled trials will be required to determine the true impact of pWB on trauma patients.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

Outcomes Among Trauma Patients with Duodenal Leak Following Primary vs Complex Repair of Duodenal Injuries: An EAST Multicenter Trial

BACKGROUND

Duodenal leak is a feared complication of repair and innovative, complex repairs with adjunctive measures(CRAM) were developed to decrease both leak occurrence and severity when leaks occur. Data on the association of CRAM and duodenal leak is sparse and its impact on duodenal leak outcomes nonexistent. We hypothesized primary repair alone (PRA) would be associated with decreased duodenal leak rates, however CRAM would be associated with improved recovery and outcomes when leaks do occur.

METHODS

A retrospective, multicenter analysis from 35 Level-1 trauma centers included patients older than 14 with operative, traumatic duodenal injuries(1/2010-12/2020). The study sample compared duodenal operative repair strategy: primary repair alone(PRA) vs CRAM(any repair plus pyloric exclusion, gastrojejunostomy, triple tube drainage, duodenectomy).

RESULTS

The sample(n = 861) was primarily young(33 years) male(84%) with penetrating injuries(77%); 523 underwent PRA and 338 underwent CRAM. CRAM were more critically injured than PRA and had higher leak rates(CRAM 21% vs PRA 8%, p < 0.001). Adverse outcomes were more common after CRAM with more IR drains, prolonged NPO and LOS, greater mortality, and more readmissions than PRA(all p < 0.05). Importantly, CRAM had no positive impact on leak recovery; there was no difference in number of operations, drain duration, NPO duration, need for IR drainage, HLOS, or mortality between PRA leak vs CRAM leak patients(all p > 0.05). CRAM leaks had longer antibiotic duration, more GI complications, and longer duration until leak resolution(all p < 0.05). PRA was associated with 60% lower odds of leak, whereas injury grade II-IV, damage control, and BMI had higher odds of leak(all p < 0.05). There were no leaks among patients with grade IV-V injuries repaired by PRA.

CONCLUSIONS

CRAM did not prevent duodenal leaks and moreover, did not reduce adverse sequelae when leaks did occur. Our results suggest CRAM is not a protective operative duodenal repair strategy and PRA should be pursued for all injury grades when feasible.

LEVEL OF EVIDENCE

IV, Multicenter retrospective comparative study.

Does Vehicle Intrusion Alone Still Predict Injury: A Retrospective Analysis of Mechanism as Trauma Activation Criteria

Automobile collisions with driver side intrusion >12 inches or >18 elsewhere meet criteria for trauma activation. However, vehicle safety features have improved since this inception. We hypothesized vehicle intrusion (VI) alone as mechanism-of-injury (MOI) criteria inadequately predicts trauma center activation. A retrospective, single-center chart review of adult patients involved in motor vehicle collisions presenting to a level 1 trauma center from July 2016 to March 2022 was performed. Patients were divided by MOI criteria: VI vs. multiple MOI criteria. 2940 patients met inclusion criteria. The VI group reported lower injury severity scores (P = 0.004), higher incidence of ED discharge (P = 0.001), lower ICU admissions (P = 0.004), and fewer in-hospital procedures (P = 0.03). Vehicle intrusion was found to have a positive likelihood ratio of 0.889 for predicting trauma center need. According to current guidelines, these results suggest that VI criteria alone may not be an accurate predictor for trauma center transport and require further investigation.

Proposed Treatment Algorithm for Invasive Fungal Infections in Trauma Patients

Background: Invasive fungal infections, most commonly caused by Mucorales species, are an underrecognized sequalae of traumatic injury that can complicate management of patients. The injury mechanism can introduce environmental spores into areas of the body normally not exposed to pathogens and this inoculation can progress rapidly to severe disease. The objective of this study was to present a case series of four trauma patients with invasive fungal infections that was used to develop an algorithm for work-up and treatment of these complex patients in future admissions. Patients and Methods: Four trauma patients who developed mucormycosis from two different hospitals are presented. One patient succumbed to their injuries whereas three were able to clear their infection with medical and surgical intervention. The surviving patients all had an infection of their lower extremity whereas the deceased patient had more extensive disease involving the thorax. Conclusions: Mucormycosis is a rare but significant post-trauma complication with substantial morbidity and mortality. Surgeons should be aware of this complication and maintain a high clinical suspicion because afflicted patients may not match the traditional clinical picture of a mucormycosis-susceptible patient. Close coordination with a pathology service is required for confirmation of the diagnosis and timely intervention can prevent debilitating loss of tissue or death. Additionally, consideration should be given to newer treatment modalities for management such as local tissue irrigation with an antifungal agent.

Management of Renal Artery-Inferior Vena Cava Fistula Following Nephrectomy for Penetrating Trauma

Background: Renal artery to inferior vena cava fistula is a rare event postnephrectomy. We report a case of an adult male in whom a renal artery to inferior vena cava fistula was detected on non-invasive studies following nephrectomy for penetrating trauma. Case Report: A fistula between the right renal artery and inferior vena cava was confirmed with diagnostic angiography. The fistula was successfully embolized using microcoils. Discussion: This case highlights the importance of exploring retroperitoneal hematomas secondary to penetrating trauma.

Does Time to Pelvic Fixation Influence Outcomes in Trauma Patients?

BACKGROUND

Pelvic fractures cause significant morbidity in the trauma population. Many factors influence time to fracture fixation. No previous study has determined the optimal time window for pelvic fixation.

METHODS

A retrospective review of trauma patients with pelvic fractures from 2016 to 2020 was performed. Patients were stratified into EARLY and LATE groups, by time to fixation within 3 days or greater than 3 days whether from admission or from completion of a life-saving procedure. Unpaired Student's t-test and Fisher's exact test were performed with multiple linear regression for variables with P < .2 on univariate analysis.

RESULTS

287 patients were identified with a median fixation time of 3 days. There was no significant difference in demographics, incidence of preceding life-saving procedure, angioembolization, or mechanism of injury in the 2 groups (P > .05). Length of stay in the EARLY group was significantly reduced at 11.9 +/- .7 days compared to 18.0 +/-1.2 days in the LATE group (P < .001). There was no significant difference in rates of ventilator-associated pneumonia, deep vein thrombosis, pulmonary embolism (PE), acute kidney injury (AKI), pressure ulcer, or acute respiratory distress syndrome (ARDS) (P > .05). There were significantly more SSIs (surgical site infections) in the LATE group. After multiple linear regression adjusting for covariates of age and ISS, the difference in hospital LOS was 5.5 days (95% CI -8.0 to -3.1, P < .001).

DISCUSSION

Fixation of traumatic pelvic fractures within 3 days reduced LOS. Prospective multi-center studies will help identify additional factors to decrease time to surgery and improve patient outcomes.

Compression of the Right Atrium and Inferior Vena Cava from an Extrahepatic Biloma Following Liver Trauma

A 26-year-old male presented to a Level 1 trauma center following a motorcycle crash. Workup of his injuries demonstrated a grade 5 liver laceration with active extravasation, grade 5 kidney laceration, right apical pneumothorax, and a sternal fracture. The patient underwent hepatic artery embolization with interventional radiology (IR) followed by an exploratory laparotomy, liver packing, and small bowel resection with primary anastomosis. Four days post-op, the patient developed dyspnea, tachycardia, and decreasing oxygen saturation. Computed tomography pulmonary angiography demonstrated perihepatic fluid compressing the right atrium and inferior vena cava. Percutaneous perihepatic drain placement with aspiration of 700 mL bilious fluid resulted in immediate resolution of the compression. He subsequently underwent endoscopic retrograde cholangiopancreatography (ERCP) with stenting of the ampulla nine days later. The patient was discharged ten days post-ERCP with oral amoxicillin/clavulanic acid for polymicrobial coverage and follow-up with gastroenterology and IR for stent removal and drain maintenance.

Bile Leak Reduction with Laparoscopic Versus Open Liver Resection: A Multi-institutional Propensity Score-Adjusted Multivariable Regression Analysis

INTRODUCTION

The reported rate of postoperative bile leak is variable between 3 and 33%. Recent data would suggest a minimally invasive approach to liver surgery has decreased this incidence.

METHODS

This multi-institutional case-control study utilized databases from three high-volume surgeons. All consecutive open and minimally invasive liver resection cases were analyzed in a propensity score-adjusted multivariable regression. A p value < 0.05 was considered significant.

RESULTS

In 1388 consecutive liver resections, the average age was 56.9 ± 14.0 years, 730 (52.59%) were male gender, and 599 (43.16%) underwent minimally invasive liver resection. Thirty-nine (2.81%) in the series were identified with post-resection bile duct leaks. Leaks were associated with major resections and increased blood loss (p < 0.05). Propensity score-adjusted multivariable regression identified minimally invasive liver resection significantly and independently reduced the odds of bile duct leak (OR 0.48, p = 0.046) even controlling for BMI, ASA, cirrhosis, major resection, and resection year.

CONCLUSIONS

Our data suggest the incidence of bile leaks in a large-volume center series is far less than previously reported and that a minimally invasive approach to liver resection reduces the incidence of postoperative bile leak.

Analysis of Plasma Products for Cellular Contaminants: Comparing Standard Preparation Methods

BACKGROUND

Recent reports suggest that component plasma products contain significant quantities of cellular contamination. We hypothesized that leukoreduction of whole blood before preparation of derived plasma is an effective method to prevent cellular contamination of stored plasma.

STUDY DESIGN

Samples of never-frozen liquid plasma prepared by standard methods (n = 25) were obtained from 3 regional blood centers that supply 3 major trauma centers. Samples were analyzed for leukocyte and platelet contamination by flow cytometry. To determine if leukoreduction of whole blood before centrifugation and expression of plasma prevents cellular contamination of liquid plasma, 1 site generated 6 additional units of liquid plasma from leukoreduced whole blood, which were then compared with units of liquid plasma derived by standard processing.

RESULTS

Across all centers, each unit of never-frozen liquid plasma contained a mean of 12.8 ± 3.0 million leukocytes and a mean of 4.6 ± 2 billion platelets. Introduction of whole blood leukoreduction (LR) before centrifugation and plasma extraction essentially eliminated all contaminating leukocytes (Non-LR: 12.3 ± 2.9 million vs LR: 0.05 ± 0.05 million leukocytes) and platelets (Non-LR: 4.2 ± 0.3 billion platelets vs LR: 0.00 ± 0.00 billion platelets).

CONCLUSIONS

Despite widespread belief that stored plasma is functionally acellular, testing of liquid plasma from 3 regional blood banks revealed a significant amount of previously unrecognized cellular contamination. Introduction of a leukoreduction step before whole blood centrifugation essentially eliminated detectable leukocyte and platelet contaminants from plasma. Therefore, our study highlights a straightforward and cost-effective method to eliminate cellular contamination of stored plasma.

Zero Preventable Deaths by 2020: Analysis of Prehospital and Emergency Department Deaths Following Penetrating Trauma Stratified by Anatomic Location

INTRODUCTION

Preventable deaths following trauma are high and unchanged over the last two decades. The objective of this study was to describe the location of death in patients with penetrating trauma, stratified by anatomic location of injury, in order to better tailor our approach to reducing preventable deaths from trauma.

METHODS

This retrospective analysis of a prospectively maintained trauma registry included consecutive adult trauma activations with penetrating trauma at a level 1 trauma center between 07/2012 and 03/2018. Injuries were categorized as extremity, junctional, and torso. Head and neck injuries were excluded. Patients injured in >1 defined location were categorized as "multiple." Location of death was defined as on-scene, emergency department (ED), or hospital. Two-sided χ² tests were used to compare groups. Multivariate analysis was performed using logistic regression.

RESULTS

A total of 1024 patients were included with an overall case fatality rate (CFR) of 7.8%. The CFR following extremity injury (3.0%) was significantly lower than all other injury sites (P = .02).There were no significant differences in CFR for junctional (10.4%), torso (8.3%), or multiple injuries (9.6%). Forty percent of fatalities following junctional injury occurred on-scene and an additional 20% occurred in the ED.

DISCUSSION

To our knowledge, this is the first study to describe location of death stratified by anatomic location of injury. There was no difference in the CFRs of junctional and torso injuries, and a large proportion of deaths occurred prior to reaching the hospital or in the trauma bay. These findings support reevaluating the classical algorithms and care pathways for patients with proximal penetrating trauma.

1126 Relationship Between Headache and Sleep: A Longitudinal Study from the Population of Sao Paulo City (Brazil)

Introduction

The complaint of nocturnal awakening with headache (NAH), was prevalent (8.4%) in the São Paulo population and was associated with sleep disturbances, as demonstrated in a study conducted in 2007 (EPISONO). Indeed, this relationship between sleep and headache is well documented in the literature. Objective: To assess the incidence and evolution of NAH and to associate sleep-related variables in an eight-year prospective study.

Methods

From 1042 volunteers enrolled in the baseline, 712 agreed to participate in the follow-up. Questionnaires and scales were applied and polysomnography and actigraphy performed. The complaint of NAH was analyzed according to a frequency questionnaire and separated into frequent or occasional.

Results

At follow-up, 110 volunteers reported NAH, of which 82 were the same as those from the baseline, but only 38 had frequent complaints. Comparing with volunteers whose headache has become occasional, we have as a difference the insomnia severity index which is significantly higher in the group with frequent NAH (8.40 ± 5.10 vs 11.20±6.40 p:0.03) and worse sleep quality as measured by the Pittsburgh questionnaire (7.25±3.60 vs 10.25±4.60 p:0.002). In addition, these volunteers had higher anxiety (10.40±9.30 vs 12.00± 10:00 p: 0.008) and depression (10.60±9.90 vs 12:00±9.90 p:0.005) from Beck’s questionnaires and greater fatigue (4.85±3.10 vs 9.75±5.55 p:0.001). The associations of NAH with insomnia, nightmares, and bruxism observed in the baseline continued, but no difference was observed between those who had frequent or occasional complaints at follow-up.

Conclusion

Our study showed that NAH was highly prevalent in the Sao Paulo population in both the baseline and follow-up studies, but this frequency had a reduction in follow-up. Volunteers who persisted with the frequent complaint showed greater severity of insomnia, higher anxiety and depression and greater fatigue.

Support

Associação Fundo de Incentivo à Pesquisa (AFIP) and São Paulo Research Foundation (FAPESP)

Outcomes in patients with gunshot wounds to the brain

Introduction

Gunshot wounds to the brain (GSWB) confer high lethality and uncertain recovery. It is unclear which patients benefit from aggressive resuscitation, and furthermore whether patients with GSWB undergoing cardiopulmonary resuscitation (CPR) have potential for survival or organ donation. Therefore, we sought to determine the rates of survival and organ donation, as well as identify factors associated with both outcomes in patients with GSWB undergoing CPR.

Methods

We performed a retrospective, multicenter study at 25 US trauma centers including dates between June 1, 2011 and December 31, 2017. Patients were included if they suffered isolated GSWB and required CPR at a referring hospital, in the field, or in the trauma resuscitation room. Patients were excluded for significant torso or extremity injuries, or if pregnant. Binomial regression models were used to determine predictors of survival/organ donation.

Results

825 patients met study criteria; the majority were male (87.6%) with a mean age of 36.5 years. Most (67%) underwent CPR in the field and 2.1% (n=17) survived to discharge. Of the non-survivors, 17.5% (n=141) were considered eligible donors, with a donation rate of 58.9% (n=83) in this group. Regression models found several predictors of survival. Hormone replacement was predictive of both survival and organ donation.

Conclusion

We found that GSWB requiring CPR during trauma resuscitation was associated with a 2.1% survival rate and overall organ donation rate of 10.3%. Several factors appear to be favorably associated with survival, although predictions are uncertain due to the low number of survivors in this patient population. Hormone replacement was predictive of both survival and organ donation. These results are a starting point for determining appropriate treatment algorithms for this devastating clinical condition.

Level of evidence

Level II.

Apalutamide and overall survival in non-metastatic castration-resistant prostate cancer

BACKGROUND

In the SPARTAN study, compared with placebo, apalutamide added to ongoing androgen deprivation therapy significantly prolonged metastasis-free survival (MFS) and time to symptomatic progression in patients with high-risk non-metastatic castration-resistant prostate cancer (nmCRPC). Overall survival (OS) results at the first interim analysis (IA1) were immature, with 104 of 427 (24%) events required for planned final OS analysis. Here, we report the results of a second pre-specified interim analysis (IA2).

METHODS

One thousand two hundred and seven patients with nmCRPC were randomized 2 : 1 to apalutamide (240 mg daily) or placebo. The primary end point of the study was MFS. Subsequent therapy for metastatic CRPC was permitted. When the primary end point was met, the study was unblinded. Patients receiving placebo who had not yet developed metastases were offered open-label apalutamide. At IA2, pre-specified analysis of OS was undertaken, using a group-sequential testing procedure with O'Brien-Fleming-type alpha spending function. Safety and second progression-free survival (PFS2) were assessed.

RESULTS

Median follow-up was 41 months. With 285 (67% of required) OS events, apalutamide was associated with an improved OS compared with placebo (HR 0.75; 95% CI 0.59-0.96; P = 0.0197), although the P-value did not cross the pre-specified O'Brien-Fleming boundary of 0.0121. Apalutamide improved PFS2 (HR 0.55; 95% CI 0.45-0.68). At IA2, 69% of placebo-treated and 40% of apalutamide-treated patients had received subsequent life-prolonging therapy for metastatic CRPC. No new safety signals were observed.

CONCLUSION

In patients with nmCRPC, apalutamide was associated with a 25% reduction in risk of death compared with placebo. This OS benefit was observed despite crossover of placebo-treated patients and higher rates of subsequent life-prolonging therapy for the placebo group.

Is Time of the Essence: A Retrospective Analysis of Operating Room Procedure Length for First Phase Damage Control Trauma Surgery

Background:The concept of Damage Control Surgery (DCS) consists of a truncated surgical intervention with main focus on hemorrhage and contamination control. Traditionally,DCS involves limiting operating room (OR) time for patients with multiple life-threatening injuries and coagulopathy who are reaching physiologic exhaustion. However, in the modern era of hemostatic resuscitation, there is a paucity of evidence to support a survival benefit with shorter OR times. The objective of this study was to determine the practice habits of trauma surgeons in the modern era of DCS and to determine if operation length affects mortality in trauma patients with abdominal injuries. Methods:An 8-year retrospective review of consecutive adult patients with DCSfor penetrating abdominal trauma at a Level I trauma center was conducted. Patient demographics, injury severity score (ISS), and penetrating abdominal trauma index (PATI) scores were obtained. Average operating room times for initial DCS were determined. Patient outcomes were analyzed with a t-test for univariate analysis and a Cox proportional hazard ratio modeling was used to predict factors for survival.  Results:A total of 193 patients were included in the study.  The overall patient mortality was 14.0% (n=27/193). Median OR time was 157 minutes (range, 59-573 min). Patients were stratified into short OR group (SHORT, n=95) and long OR group (LORT, n=98) based on the median operative time. Only one patient had an initial DCL less than 60 minutes.  The SHORT group received more blood transfusions (52.6% vs. 35.7%, p=0.02) in the ICU. Average operative room time was almost twice as long in the LORT group (214.6+6.2 vs. 121.4+2.6 minutes, p<0.0001). The average hospital length of stay (22.8+2.3 vs. 31.0+3.5 days, p=0.05) and ICU length of stay (10.6+1.2 vs. 12.6+1.4 days, p=0.28) were both lower in the LORT group compared to the SHORT group. The SHORT group had 22 patients with unplanned return to the OR compared to 3 in the LORT group (p<0.0001). On multivariate analysis, OR time was not an independent risk factor for mortality (OR 1.0, 95% CI 0.98-1.0, p=0.48). Conclusions: Modern damage control practices should focus on early and effective surgical hemorrhage control in combination with effective intra-op hemostatic resuscitation efforts and not on how time limitations. These findings suggest that OR time restrictions in the era of effective hemostatic resuscitation in combination with DCS does not impact mortality.

Plasma Transfusion Products and Contamination with Cellular and Associated Pro-Inflammatory Debris

BACKGROUND

Stored plasma products are widely regarded as being functionally acellular, obviating the need for leukoreduction. We tested the hypothesis that donor plasma is contaminated by leukocytes and platelets, which, after frozen storage, would release cellular debris in quantities sufficient to elicit significant pro-inflammatory responses.

STUDY DESIGN

Samples of never-frozen liquid plasma from 2 regional Level I trauma centers were analyzed for leukocyte and platelet contamination. To determine if the cellular contamination and associated debris found in liquid plasma were at levels sufficient to evoke an innate immune response, known quantities of leukocytes were subjected to a freeze-thaw cycle, added to whole blood, and the magnitude of the inflammatory response was determined by induction of interleukin-6.

RESULTS

Units of never-frozen plasma from 2 regional Level I trauma centers located in Alabama and Louisiana contained significant amounts of leukocyte contamination (Louisiana, n = 22; 17.3 ± 4.5 million vs Alabama, n = 22; 11.3 ± 2.2 million) and platelet contamination (Louisiana, n = 21; 0.86 ± 0.20 billion vs Alabama, n = 22; 1.0 ± 0.3 billion). Cellular debris from as few as 1 million leukocytes induced significant increases in interleukin-6 levels (R² = 0.74; p < 0.0001).

CONCLUSIONS

Stored plasma units from trauma center blood banks were highly contaminated with leukocytes and platelets, at levels more than 15-fold higher than sufficient to elicit ex vivo inflammatory responses. In light of paradigm shifts toward the use of more empiric plasma for treatment of hypovolemia, this study suggests that new manufacturing and quality-control processes are needed to eliminate previously unrecognized cellular contamination present in stored plasma products.

Unstable Without a Source: The Non-Diagnostic Triad in Hypotensive Blunt Trauma Victims

Background: Current algorithms for resuscitation in blunt trauma patients rely on chest x-ray, FAST, and pelvic x-ray to quickly elicit a source of major bleeding in the trauma bay.  There are currently no good recommendations for the patient in whom all three of these imaging studies are negative.  Methods:  We identified blunt trauma victims who presented with a systolic blood pressure below 100mmHg.  Chest x-ray, FAST, and pelvic x-ray obtained in the trauma bay were reviewed, and patients who had all three studies negative underwent thorough chart review and characterization of injuries.   Results:  Of the total hypotensive blunt trauma victims (n=649), we found 47 who had a “non-diagnostic triad” (NDT).  Of the NDT group, 31.9% (n=15) were found to have a major injury contributing to hypotension, while 61% (n=29) were not diagnosed with a severe injury that could have contributed to hypotension.  Of the NDT group with severe injury, 40% (n=6) were found to have retroperitoneal bleeding, 40% (n=6) were found to have intraperitoneal bleeding despite negative fast, 13% (n=2) were thought to have spinal shock, and one patient had a blunt cardiac injury.    Conclusions:  Most of the NDT group patients in this study were not diagnosed with a serious injury.  However, a significant minority (31%) were found to have a major injury contributing to hypotension.  Of these patients, retroperitoneal and/or intra-abdominal bleeding were found in 80%, with neurogenic and cardiogenic shock less common.  We feel these sicker NDT patients may benefit from REBOA, although more study is warranted before formal algorithms and recommendations are made. 

WNT-activated bone grafts repair osteonecrotic lesions in aged animals

The Wnt pathway is a new target in bone therapeutic space. WNT proteins are potent stem cell activators and pro-osteogenic agents. Here, we gained insights into the molecular and cellular mechanisms responsible for liposome-reconstituted recombinant human WNT3A protein (L-WNT3A) efficacy to treat osteonecrotic defects. Skeletal injuries were coupled with cryoablation to create non-healing osteonecrotic defects in the diaphysis of the murine long bones. To replicate clinical therapy, osteonecrotic defects were treated with autologous bone graft, which were simulated by using bone graft material from syngeneic ACTB-eGFP-expressing mice. Control osteonecrotic defects received autografts alone; test sites received autografts treated ex vivo with L-WNT3A. In vivo µCT monitored healing over time and immunohistochemistry were used to track the fate of donor cells and assess their capacity to repair osteonecrotic defects according to age and WNT activation status. Collectively, analyses demonstrated that cells from the autograft directly contributed to repair of an osteonecrotic lesion, but this contribution diminished as the age of the donor increased. Pre-treating autografts from aged animals with L-WNT3A restored osteogenic capacity to autografts back to levels observed in autografts from young animals. A WNT therapeutic approach may therefore have utility in the treatment of osteonecrosis, especially in aged patients.

Liver transplantation in New Orleans: parity in a world of disparity?

BACKGROUND

Racial disparity in access to liver transplantation among African Americans (AA) compared to Caucasians (CA) has been well described. The aim of this investigation was to examine the presentation of AA liver transplant recipients in a socioeconomically challenged region.

METHODS

680 adult liver transplant candidates and 233 resultant recipients between 2007 and 2015 were analyzed using univariate and multivariate analyses to evaluate factors significant for transplantation.

RESULTS

Percentages of wait list patients transplanted were similar between CA and AA (34.9% vs. 32.2%, p = 0.5205). AA were younger (50.4 ± 1.8 vs. 56.3 ± 0.7 yrs, p = 0.0003) with higher average MELD scores (22.9 ± 1.6 vs. 19.4 ± 0.7, p = 0.0230). Overall patient mortality was similar (AA 22.7% vs. CA 26.3%, p = 0.5931). A multiple linear regression showed that male gender was strongly associated with transplantation.

CONCLUSIONS

Equal access to liver transplantation remains challenging for racial minorities. At our institution, AA were accepted and transplanted at an equivalent rate as CA despite a higher AA population, HCV rate and diagnosed HCC. AA were younger and sicker at the time of transplant, but overall had similar outcomes compared to CA. Our study highlights the need for studies to delineate the underpinnings of disparity in transplantation access.

Retroperitoneal Hematoma Causing Peritoneal Dialysis Catheter Malfunction

BACKGROUND

We present the unusual complication of peritoneal dialysis catheter dysfunction in a patient who developed a retroperitoneal hematoma following an endoscopic procedure and review the existing literature regarding this rare complication.

CASE REPORT

A 60-year-old male with end stage renal disease presented with PD catheter dysfunction. A computerized tomography scan of his abdomen showed a large left retroperitoneal hematoma. He underwent a diagnostic laparoscopy and PD catheter revision. The retroperitoneal hematoma had ruptured into the peritoneum with clots clogging the catheter. Clots were evacuated and the catheter was flushed. He restarted on low--volume PD three days after surgery and increased to full-volume within a week with no further issues.

CONCLUSIONS

This case summarizes the unusual complication of a retroperitoneal bleed from an endoscopic procedure which manifested as PD catheter dysfunction. The increasing utilization of PD catheters requires surgeons remain aware of potential complications.

Repeated immunostaining of the same tissue section using alkaline phosphatase as a reporter

One can determine the best dilution of a primary antibody for immunohistochemistry that uses horseradish peroxidase conjugated to a secondary antibody by testing increasing concentrations sequentially on the same tissue section. When the same tissue section is incubated repeatedly with increasing concentrations of primary antibodies to epithelial membrane antigen, smooth muscle α-actin, or vimentin using alkaline phosphatase conjugated to a secondary antibody as the reporter, the best staining was obtained with a less concentrated primary antibody than was optimal for a single staining test. The best concentration of primary antibody for single run staining using an alkaline phosphatase reporting system is usually four times the best concentration for staining with multiple runs. The optimal concentration can be determined by denaturing the residual alkaline phosphatase and extracting residual stain by incubating the section in 4:1 diglyme:phosphate buffered saline for 20 min at 80(o) C between tests of primary antibody concentrations. I tested the method for four chromogens from one supplier and one chromogen from a different supplier.

Retroperitoneal Hematoma Causing Peritoneal Dialysis Catheter Malfunction

BACKGROUND

We present the unusual complication of peritoneal dialysis (PD) catheter dysfunction in a patient who developed a retroperitoneal hematoma following an endoscopic procedure and review the existing literature regarding this rare complication.

CASE REPORT

A 60-year-old man with end stage renal disease presented with PD catheter dysfunction. Computed tomography scan of his abdomen showed a large left retroperitoneal hematoma. He underwent a diagnostic laparoscopy and PD catheter revision. The retroperitoneal hematoma had ruptured into the peritoneum with clots clogging the catheter. Clots were evacuated and the catheter was flushed. He restarted on low volume PD three days after surgery and increased to full volume within a week with no further issues.

CONCLUSIONS

This case summarizes the very unusual complication of a retroperitoneal bleed from an endoscopic procedure that manifested as PD catheter dysfunction. The increasing utilization of PD catheters requires that surgeons remain aware of potential complications.

Accuracy of ultrasonography performed by examiners with varied training and experience in predicting specific pathology of adnexal masses

OBJECTIVES

To assess the diagnostic performance of subjective assessment by Level II ultrasound examiners in predicting the specific histology of adnexal masses.

METHODS

The women included in this prospective multicenter cross-sectional study were older than 16 years of age and had at least one adnexal mass. They underwent transvaginal sonography (TVS) performed by Level II examiners, all of whom were familiar with the International Ovarian Tumor Analysis (IOTA) group definitions of ultrasound features of ovarian masses. The final outcome was histology. Specific diagnoses were categorized into 16 groups. Agreement between subjective assessment and final histology was measured using unweighted kappa coefficients. Sensitivities and specificities were obtained for subjective assessment.

RESULTS

Of the 1279 women who underwent TVS, 313 were included in the final analysis. Overall agreement (16 × 16 table) between subjective assessment and histology was moderate, with a Cohen's kappa coefficient of 0.59 (95% CI, 0.53-0.65). The specificity of subjective assessment ranged between 91% and 100% for all histological subgroups. Highest sensitivities were achieved in the diagnosis of simple cysts (100% (95% CI, 61-100%)), hydrosalpinges (100% (95% CI, 34-100%)), mature teratomas (88% (95% CI, 74-96%)), endometriomas (75% (95% CI, 61-85%)), ovarian fibromas (88% (95% CI, 47-100%)), tubo-ovarian abscesses (88% (95% CI, 47-100%)) and serous cystadenocarcinomas (82% (95% CI, 66-93%)). Serous cystadenomas were misdiagnosed most commonly (40.5%). The sensitivity of subjective assessment in diagnosing adnexal torsion was 54% (95% CI, 25-81%); the 17 confirmed and/or suspected cases of adnexal torsion were not included in the 313 cases examined and analyzed for diagnostic performance.

CONCLUSION

Overall, subjective assessment by Level II examiners was good for the detection of simple cysts, endometriomas, mature teratomas, hydrosalpinges, fibroma, tubo-ovarian abscess and serous cystadenocarcinomas.

Multiscale analyses of the bone-implant interface

Implants placed with high insertion torque (IT) typically exhibit primary stability, which enables early loading. Whether high IT has a negative impact on peri-implant bone health, however, remains to be determined. The purpose of this study was to ascertain how peri-implant bone responds to strains and stresses created when implants are placed with low and high IT. Titanium micro-implants were inserted into murine femurs with low and high IT using torque values that were scaled to approximate those used to place clinically sized implants. Torque created in peri-implant tissues a distribution and magnitude of strains, which were calculated through finite element modeling. Stiffness tests quantified primary and secondary implant stability. At multiple time points, molecular, cellular, and histomorphometric analyses were performed to quantitatively determine the effect of high and low strains on apoptosis, mineralization, resorption, and collagen matrix deposition in peri-implant bone. Preparation of an osteotomy results in a narrow zone of dead and dying osteocytes in peri-implant bone that is not significantly enlarged in response to implants placed with low IT. Placing implants with high IT more than doubles this zone of dead and dying osteocytes. As a result, peri-implant bone develops micro-fractures, bone resorption is increased, and bone formation is decreased. Using high IT to place an implant creates high interfacial stress and strain that are associated with damage to peri-implant bone and therefore should be avoided to best preserve the viability of this tissue.

Cell viability after osteotomy and bone harvesting: comparison of piezoelectric surgery and conventional bur

The aim of this study was to evaluate and compare the influence of a piezoelectric device versus a conventional bur on osteocyte viability and osteoblast and osteoclast activity using an in vivo mouse model. Osteotomies were created and bone grafts were harvested using either a conventional bur or a piezoelectric device; the resulting injuries and bone grafts were evaluated over an extended time-course using molecular and cellular assays for cell death (TUNEL assay), cell viability (4',6-diamidino-2-phenylindole (DAPI) staining), the onset of mineralization (alkaline phosphatase activity), and bone remodelling (tartrate-resistant acid phosphatase activity). Osteotomies created with a piezoelectric device showed greater osteocyte viability and reduced cell death. Bone grafts harvested with a piezoelectric device exhibited greater short-term cell viability than those harvested with a bur, and exhibited slightly more new bone deposition and bone remodelling. The difference in response of osteocytes, osteoblasts, and osteoclasts to bone cutting via a bur and via a piezoelectric device is negligible in vivo. Given the improved visibility and the margin of safety afforded by a piezoelectric device, they are the instrument of choice when cutting or harvesting bone to preserve soft tissue.

A multicenter prospective external validation of the diagnostic performance of IOTA simple descriptors and rules to characterize ovarian masses

OBJECTIVES

To evaluate the diagnostic performance of the IOTA (International Ovarian Tumor Analysis group) (clinically oriented three-step strategy for preoperative characterization of ovarian masses when ultrasonography is performed by examiners with different background training and experience.

METHODS

A 27-month prospective multicenter cross-sectional study was performed. 36 level II ultrasound examiners contributed in three UK hospitals. Transvaginal ultrasonography was performed using a standardized approach. Step one uses simple descriptors (SD), step two ultrasound simple rules (SR) and step three subjective assessment of ultrasound images (SA) by examiners. The final outcome was findings at surgery and the histological diagnosis of surgically removed masses.

RESULTS

1165 women with adnexal masses underwent transvaginal ultrasonography, 301 had surgery. Prevalence of malignancy was 31% (n=92). SD were able to classify 46% of the masses into benign or malignant (step one), with a sensitivity of 93% and specificity of 97%. Applying SD followed by SR to residual unclassified masses by SD enabled 89% of all masses (n=268) to be classified with a sensitivity 95% of and specificity of 95%. SA was then used to evaluate the rest of the masses. Compared to the risk of malignancy index (RMI), the sensitivity and specificity for the three-step (SD+SR+SA) strategy were 93% (95% CI: 86-97%) and 92% (95% CI: 87-95%) vs. 72% (95% CI: 62-80%) and 95% (95% CI: 91-97%) for RMI, respectively.

CONCLUSION

The IOTA three-step strategy shows good test performance on external validation in the hands of ultrasonography examiners with different background training and experience. This performance is considerably better than the RMI.

Wild bees visiting cucumber on midwestern U.S. organic farms benefit from near-farm semi-natural areas

Wild bees that provide pollination services to vegetable crops depend on forage resources, nesting sites, and overwintering sites in the agricultural landscape. The scale at which crop-visiting bees use resources in the landscape can vary regionally, and has not been characterized in the Midwestern United States. We investigated the effects of seminatural land cover on wild bee visitation frequency to cucumber (Cucumis sativus L.) and on wild bee species richness on 10 organic farms in Indiana. We estimated the spatial scale at which the effects of land cover were strongest, and also examined the effects of nonlandscape factors on wild bees. The visitation frequency of wild bees to cucumber was positively related to the proportion of seminatural land in the surrounding landscape, and this relationship was strongest within 250 m of the cucumber patch. The species richness of wild cucumber visitors was not affected by land cover at any spatial scale, nor by any of the nonlandscape factors we considered. Our results indicate that wild, crop visiting bees benefit from seminatural areas in the agricultural landscape, and benefit most strongly from seminatural areas within 250 m of the crop field. This suggests that setting aside natural areas in the near vicinity of vegetable fields may be an effective way to support wild, crop-visiting bees and secure their pollination services.