Type-specific whole blood still has a role in the era of low titer O universal donor transfusion for severe trauma hemorrhage.

ABSTRACT: Whole blood can be ABO-type specific (TSWB) or Low-Titer O universal donor (LTOWB). Having previously used LTOWB, the US Armed Forces Blood Program began using TSWB in 1965 as a method of increasing the donor pool. In contrast to military practice, the AABB (Association for the Advancement of Blood and Biotherapies), from its first guidelines in 1958 until 2018, permitted only TSWB. Attempting to reduce time to transfusion, the US military reintroduced LTOWB in the deployed environment in 2015; this practice was endorsed by the AABB in 2018 and is progressively being implemented by military and civilian providers worldwide. LTOWB is the only practical solution prehospital. However, there are several reasons to retain the option of TSWB in hospitals with a laboratory. These include 1. as-yet ill-defined risks of immunological complications from ABO-incompatible plasma (even when this has low titres of anti A and B); 2. risks of high volumes of LTOWB including published historical advice (based on clinical experience) not to transfuse type-specific blood for 2-3 weeks following a substantial LTOWB transfusion; 3. uncertainty as to the optimal definition of "low titre"; and 4. expanding the potential donor pool by allowing type-specific transfusion. Several large randomised controlled trials currently underway are comparing LTOWB to component therapy, but none address the question of LTOWB vs. TSWB. There is sufficient data to suggest the additional risks of transfusing LTOWB to non-group O recipients should be avoided by using TSWB as soon as possible. Combined with the advantage of maintaining an adequate supply of blood products in times of high demand, this suggests retaining TSWB within the civilian and military blood supply system is desirable. TSWB should be preferred when patient blood group is confirmed in facilities with a hematology laboratory, with LTOWB reserved for patients whose blood group is unknown.

Management of non-union of rib fractures secondary to trauma: A scoping review.

OBJECTIVE: Rib fracture non-union is an uncommon complication of traumatic rib fractures. Our objective was to perform a scoping review of the literature for the management of rib fracture non-union. This included analysis of the variations in surgical technique, complications experienced, and reported outcomes. METHODS: We conducted a scoping review and searched databases (MEDLINE, CINAHL, and Embase). We performed abstract and full-text screening, and abstracted data related to pre-operative assessment, surgical technique, complications, and reported outcome measures. RESULTS: We included 29 articles of which 19 were case reports and 10 were case series. The data quality was generally heterogeneous. The studies included 229 patients and the commonest symptoms of rib fracture non-union included chest pain, clicking, dyspnea and deformities. The patients underwent surgical management of rib fracture non-union (excluding first rib fractures) using various techniques. The majority used surgical stabilization of rib fracture with or without a graft. The reported outcomes were inconsistent between studies, but showed high rates of union (>94 %), reduction in reported VAS scores, and improved return to work when included. Implant failure occurred in 10 % of the 229 total patients reported in our studies, the re-operation rate was 13 %, and the overall complication rate was 27 %. CONCLUSION: Surgical management of rib fracture non-union often involving locking plates and screws with or without a graft has been shown in several case reports and series as an effective treatment with acceptable implant failure and complication rates. Surgical management is therefore a viable option for symptomatic patients. Further research is required to determine optimal management strategies that further reduce surgical complications for these patients.

Management of Rib Fractures in the Combat Environment.

Rib fractures in combat casualties are an under-appreciated injury, and their treatment may become more common as more patients survive because of modern body armor and point-ofinjury care. The combat environment has challenges such as equipment availability and sterility. A simple and thoughtful rib fracture treatment algorithm may be useful to reduce the morbidity and mortality of rib fractures in the combat environment. Intravenous lidocaine infusions for patients with traumatic rib fractures may have important combat applications. We propose an algorithm for the management of combat casualties with traumatic rib fractures.

Post-Reconstitution Hemostatic Stability Profiles of Canadian and German Freeze-Dried Plasma.

Despite the importance of the hemostatic properties of reconstituted freeze-dried plasma (FDP) for trauma resuscitation, few studies have been conducted to determine its post-reconstitution hemostatic stability. This study aimed to assess the short- (≤24 h) and long-term (≥168 h) hemostatic stabilities of Canadian and German freeze-dried plasma (CFDP and LyoPlas) after reconstitution and storage under different conditions. Post-reconstitution hemostatic profiles were determined using rotational thromboelastometry (ROTEM) and a Stago analyzer, as both are widely used as standard methods for assessing the quality of plasma. When compared to the initial reconstituted CFDP, there were no changes in ROTEM measurements for INTEM maximum clot firmness (MCF), EXTEM clotting time (CT) and MCF, and Stago measurements for prothrombin time (PT), partial thromboplastin time (PTT), D-dimer concentration, plasminogen, and protein C activities after storage at 4 °C for 24 h and room temperature (RT) (22-25 °C) for 4 h. However, an increase in INTEM CT and decreases in fibrinogen concentration, factors V and VIII, and protein S activities were observed after storage at 4 °C for 24 h, while an increase in factor V and decreases in antithrombin and protein S activities were seen after storage at RT for 4 h. Evaluation of the long-term stability of reconstituted LyoPlas showed decreased stability in both global and specific hemostatic profiles with increasing storage temperatures, particularly at 35 °C, where progressive changes in CT and MCF, PT, PTT, fibrinogen concentration, factor V, antithrombin, protein C, and protein S activities were seen even after storage for 4 h. We confirmed the short-term stability of CFDP in global hemostatic properties after reconstitution and storage at RT, consistent with the shelf life of reconstituted LyoPlas. The long-term stability analyses suggest that the post-reconstitution hemostatic stability of FDP products would decrease over time with increasing storage temperature, with a significant loss of hemostatic functions at 35 °C compared to 22 °C or below. Therefore, the shelf life of reconstituted FDP should be recommended according to the storage temperature.

Past meets present: Reviving 80-year-old Canadian dried serum from World War II and its significance in advancing modern freeze-dried plasma for prehospital management of haemorrhage.

During World War II, Charles H. Best utilized Charles R. Drew's plasma isolation and drying technique to lead Canada's initiative to provide dried serum as a means of primary resuscitation for British casualties on the frontlines. Serum was likely utilized over plasma for its volume expansion properties without the risk of clotting during prolonged storage. We reconstituted dried serum from 1943 and discovered intact albumin, as well as anti-thrombin, plasminogen, protein C and protein S activity. Proteomic analysis identified 71 proteins, most prominent being albumin, and positive for hepatitis B by serological testing. Transmission of blood-borne diseases ended the programme, until modern advances in testing and pathogen reduction revived this technology. We tested the latest iteration of Canadian freeze-dried plasma (FDP), which was stored for 4 years, and demonstrated that its clotting capacity remained equivalent to fresh frozen plasma. We recommend that FDP is a strong alternative to contemporary prehospital resuscitation fluids (e.g. normal saline/lactated Ringer's) in managing prehospital haemorrhage where whole blood is unavailable.

Advanced Non-compressible Torso Hemorrhage Management is Combat Casualty Care's Moon Shot.

Non-compressible torso hemorrhage continues to cause considerable preventable mortality on the battlefield. In this editorial, we highlight the burden of deaths, the most at-risk torso structures, current interventions, and their limitations and recommendations for future research and device development.

Prehospital Freeze-Dried Plasma in Trauma: A Critical Review.

Major traumatic hemorrhage is now frequently treated by early hemostatic resuscitation on hospital arrival. Prehospital hemostatic resuscitation could therefore improve outcomes for bleeding trauma patients, but there are logistical challenges. Freeze-dried plasma (FDP) offers indisputable logistical advantages over conventional blood products, such as long shelf life, stability at ambient temperature, and rapid reconstitution without specialized equipment. We sought high level, randomized, controlled evidence of FDP clinical efficacy in trauma. A structured systematic search of MEDLINE/PubMed was carried out and identified 52 relevant English language publications. Three studies involving 607 patients met our criteria: Resuscitation with Blood Products in Patients with Trauma-related Hemorrhagic Shock receiving Prehospital Care (RePHILL, n = 501); Prehospital Lyophilized Plasma Transfusion for Trauma-Induced Coagulopathy in Patients at Risk for Hemorrhagic Shock (PREHO-PLYO, n = 150); and a pilot Australian trial (n = 25). RePHILL found no effect of FDP plus packed red blood cells (PRBC) concentrate transfusion versus saline on mortality. PREHO-PLYO found no effect of FDP versus saline on International Normalized Ratio (INR) at hospital arrival. The pilot trial found that study of PRBC versus PRBC plus FDP was feasible during long air transport times to an Australian trauma centre. Further research is required to determine under what conditions FDP might provide prehospital benefit to trauma patients.

A comparative analysis of current out-of-hospital transfusion protocols to expert recommendations.

Aim: This study aimed to compare current out-of-hospital transfusion (OHT) protocols in Canadian civilian critical care transport organizations (CCTO) to expert recommendations and explore the variability and potential benefits of standardizing OHT practices across Canada. Methods: A comprehensive cross-sectional study was conducted, encompassing all seven Canadian CCTOs that provide OHT. The study assessed adherence to expert recommendations and examined specific aspects of the transfusion process, such as indications for transfusion and cessation criteria. Results: The study found an 89% adherence to expert recommendations for OHT among Canadian CCTOs. It highlighted a strong alignment between current practices and recommendations, possibly attributed to collaborative frameworks like the CAN-PATT network. However, notable variability and ambiguity were observed in transfusion indications and cessation criteria. The study also emphasized the potential benefits of standardizing OHT practices, such as improved policy formulation, better interpretation of emerging literature, and evaluation of OHT efficacy. Conclusion: This cross-sectional study assessed how Canadian CCTOs implement OHT practices compared to expert-recommended practices. The findings underscore the importance of structured protocols in trauma management. Given the consistency in OHT protocol adoption and the comprehensive approach across CCTOs, there's a solid foundation for managing trauma patients in prehospital and transport settings across Canada. As OHT practices continue to evolve, sustained efforts are vital to refine, adapt, and elevate patient care standards in trauma management.

Ruggedized Self-Propelling Hemostatic Gauze Delivers Low Dose of Thrombin and Systemic Tranexamic Acid and Achieves High Survival in Swine With Junctional Hemorrhage.

INTRODUCTION: Hemorrhage is responsible for 91% of preventable prehospital deaths in combat. Bleeding from anatomic junctions such as the groin, neck, and axillae make up 19% of these deaths, and reports estimate that effective control of junctional hemorrhage could have prevented 5% of fatalities in Afghanistan. Hemostatic dressings are effective but are time-consuming to apply and are limited when proper packing and manual pressure are not feasible, such as during care under fire. CounterFlow-Gauze is a hemostatic dressing that is effective without compression and delivers thrombin and tranexamic acid into wounds. Here, an advanced prototype of CounterFlow-Gauze, containing a range of low thrombin doses, was tested in a lethal swine model of junctional hemorrhage. Outcomes were compared with those of Combat Gauze, the current dressing recommended by Tactical Combat Casualty Care. MATERIALS AND METHODS: CounterFlow-Gauze containing thrombin doses of 0, 20, 200, and 500 IU was prepared. Swine received femoral arteriotomies, and CounterFlow-Gauze was packed into wounds without additional manual compression. In a separate study using a similar model of junctional hemorrhage without additional compression, CounterFlow-Gauze containing 500 IU thrombin was tested and compared with Combat Gauze. In both studies, the primary outcomes were survival to 3 h and volume of blood loss. RESULTS: CounterFlow-Gauze with 200 and 500 IU had the highest 3-h survival, achieving 70 and 75% survival, respectively. CounterFlow-Gauze resulted in mean peak plasma tranexamic acid concentrations of 9.6 ± 1.0 µg/mL (mean ± SEM) within 3 h. In a separate study with smaller injury, CounterFlow-Gauze with 500 IU achieved 100% survival to 3 h compared with 92% in Combat Gauze animals. CONCLUSIONS: An advanced preclinical prototype of CounterFlow-Gauze formulated with a minimized thrombin dose is highly effective at managing junctional hemorrhage without compression. These results demonstrate that CounterFlow-Gauze could be developed into a feasible alternative to Combat Gauze for hemorrhage control on the battlefield.

Who are the trauma team leaders across Canada? A national survey evaluating the profession in adult and pediatric level one trauma centres.

OBJECTIVES: Trauma Team Leaders (TTLs) are critical for coordinating and leading trauma resuscitations. This survey sought to characterize the demographics and professional practices of Canadian TTLs at level one trauma centres. As a secondary objective, this information will be utilized to inform the operational goals of the Trauma Association of Canada (TAC) TTL Committee. METHODS: A detailed survey, developed by the TAC board of directors and TTL committee leads, was sent to 225 TTLs across Canada's level one trauma centres. TTLs were identified via contacting trauma directors at each level one centre, in addition to public registry searches. This survey captured demographics, professional background, resuscitation practices, trauma team composition, and TTL involvement in trauma responses. RESULTS: The response rate was 41.7%. Mean respondent age was 42 (SD 7.4) and 71.0% were male. Most TTLs trained in emergency medicine (53.1%) or general surgery (25.5%); 63.8% underwent TTL training: either via a trauma surgery fellowship or TTL fellowship. All centres have a massive hemorrhage protocol implemented, and there is no large variation between the rates of use of cryoprecipitate and fibrinogen, nor the ratio of blood products transfused (2:1 vs 1:1). Most TTL respondents intend to participate in a TTL group associated with TAC (85.1%). CONCLUSION: The results of this survey will contribute to the recognition of TTLs as a crucial role in the initial phase of care of severely injured trauma patients and serves as the first publication to document professional backgrounds and practices of Canadian TTLs at level one trauma centres. All the information gathered via this survey will be used by the TAC TTL Committee, which will focus on several initiatives such as the dissemination of best practice guidelines and creation of a TTL stream at the TAC Annual Conference.

RéSUMé: OBJECTIFS: Les chefs d'équipe de traumatologie (TTL) sont essentiels pour coordonner et diriger les réanimations traumatiques. Cette enquête visait à caractériser la démographie et les pratiques professionnelles des TTL canadiens dans les centres de traumatologie de niveau 1. À titre d'objectif secondaire, cette information sera utilisée pour éclairer les objectifs opérationnels du Comité TTL de l'Association canadienne de traumatologie (ATC). MéTHODES: Un sondage détaillé, élaboré par le conseil d'administration de l'ATC et les responsables des comités de TTL, a été envoyé à 225 TTL dans les centres de traumatologie de niveau 1 du Canada. Les TTL ont été identifiés en contactant les directeurs de traumatologie de chaque centre de niveau 1, en plus des recherches dans le registre public. Cette enquête a porté sur la démographie, les antécédents professionnels, les pratiques de réanimation, la composition de l'équipe de traumatologie et la participation de la TTL aux réponses traumatologiques. RéSULTATS: Le taux de réponse était de 41,7 %. L'âge moyen des répondants était de 42 ans (ET 7,4) et 71,0 % étaient des hommes. La plupart des TTL ont suivi une formation en médecine d'urgence (53,1%) ou en chirurgie générale (25,5%); 63,8% ont suivi une formation TTL : soit via une bourse en chirurgie traumatologique ou une bourse TTL. Tous les centres ont mis en œuvre un protocole d'hémorragie massive, et il n'y a pas de grande variation entre les taux d'utilisation du cryoprécipité et du fibrinogène, ni entre le rapport des produits sanguins transfusés (2:1 vs 1:1). La plupart des répondants TTL ont l'intention de participer à un groupe TTL associé au TAC ( 85,1 %). CONCLUSION: Les résultats de ce sondage contribueront à la reconnaissance des TTL comme un rôle crucial dans la phase initiale des soins aux patients ayant subi un traumatisme grave et serviront de première publication pour documenter les antécédents et les pratiques professionnelles des TTL canadiens au niveau un centres de traumatologie. Toutes les informations recueillies dans le cadre de cette enquête seront utilisées par le Comité TAC TTL, qui se concentrera sur plusieurs initiatives telles que la diffusion de lignes directrices sur les meilleures pratiques et la création d'un flux TTL à la conférence annuelle TAC.

Development of a national out-of-hospital transfusion protocol: a modified RAND Delphi study.

BACKGROUND: Early resuscitation with blood components or products is emerging as best practice in selected patients with trauma and medical patients; as a result, out-of-hospital transfusion (OHT) programs are being developed based on limited and often conflicting evidence. This study aimed to provide guidance to Canadian critical care transport organizations on the development of OHT protocols. METHODS: The study period was July 2021 to June 2022. We used a modified RAND Delphi process to achieve consensus on statements created by the study team guiding various aspects of OHT in the context of critical care transport. Purposive sampling ensured representative distribution of participants in regard to geography and relevant clinical specialties. We conducted 2 written survey Delphi rounds, followed by a virtual panel discussion (round 3). Consensus was defined as a median score of at least 6 on a Likert scale ranging from 1 ("Definitely should not include") to 7 ("Definitely should include"). Statements that did not achieve consensus in the first 2 rounds were discussed and voted on during the panel discussion. RESULTS: Seventeen subject experts participated in the study, all of whom completed the 3 Delphi rounds. After the study process was completed, a total of 39 statements were agreed on, covering the following domains: general oversight and clinical governance, storage and transport of blood components and products, initiation of OHT, types of blood components and products, delivery and monitoring of OHT, indications for and use of hemostatic adjuncts, and resuscitation targets of OHT. INTERPRETATION: This expert consensus document provides guidance on OHT best practices. The consensus statements should support efficient and safe OHT in national and international critical care transport programs.

Do patient outcomes differ when the trauma team leader is a surgeon or non-surgeon? A multicentre cohort study.

PURPOSE: Trauma team leaders (TTLs) have traditionally been general surgeons; however, some trauma centres use a mixed model of care where both surgeons and non-surgeons (primarily emergency physicians) perform this role. The objective of this multicentre study was to provide a well-powered study to determine if TTL specialty is associated with mortality among major trauma patients. METHODS: Data were collected from provincial trauma registries at six level 1 trauma centres across Canada over a 10-year period. We included adult trauma patients (age ≥ 18 yrs) who triggered the highest-level trauma activation. The primary outcome was the difference in risk-adjusted in-hospital mortality for trauma patients receiving initial care from a surgeon versus a non-surgeon TTL. RESULTS: Overall, 12,961 major trauma patients were included in the analysis. Initial treatment was provided by a surgeon TTL in 57.8% (n = 7513) of cases, while 42.2% (n = 5448) of patients were treated by a non-surgeon TTL. Unadjusted mortality occurred in 11.6% of patients in the surgeon TTL group and 12.7% of patients in the non-surgeon TTL group (OR 0.87, 95% CI 0.78-0.98, p = 0.02). Risk-adjusted mortality was not significantly different between patients cared for by surgeon and non-surgeon TTLs (OR 0.92, 95% CI 0.80-1.06, p = 0.23). Furthermore, we did not observe differences in risk-adjusted mortality for any of the subgroups evaluated. CONCLUSIONS: After risk adjustment, there was no difference in mortality between trauma patients treated by surgeon or non-surgeon TTLs. Our study supports emergency physicians performing the role of TTL at level 1 trauma centres.

ABSTRAIT: OBJECTIF: Les chefs d'équipe de traumatologie (CET) sont traditionnellement des chirurgiens généralistes; cependant, certains centres de traumatologie utilisent un modèle mixte de soins où des chirurgiens et des non-chirurgiens (principalement des médecins d'urgence) qui jouent ce rôle. L'objectif de cette étude multicentrique était de fournir une étude bien menée pour déterminer si la spécialité CET est associée à la mortalité chez les patients traumatisés majeurs. MéTHODES: Les données ont été recueillies à partir des registres provinciaux de 6 niveau 1 centres de traumatologie au Canada sur une période de 10 ans. Nous avons inclus des patients adultes traumatisés (âge ≥ 18 ans) qui ont provoqué l'activation traumatique de niveau le plus haut. Le primaire résultat était la différence de mortalité hospitalière ajustée en fonction du risque pour les patients traumatisés qui ont reçu des soins primaires d'un chirurgien par rapport à un CET non chirurgien. RéSULTATS: En totale, 12 961 patients traumatisés majeurs ont été la partie de cette analyse. Le soin primaire a été assuré par un chirurgien CET dans 57,8 % (n=7 513) des cas, alors que 42,2 % (n=5 448) des patients ont été traités par un CET non chirurgien. Une mortalité non ajustée s'est produit chez 11,6 % des patients du groupe de chirurgien CET et 12,7 % des patients du groupe de non chirurgien CET (OR 0,87, IC à 95 % 0,78 à 0,98, p = 0,02). La mortalité ajustée en fonction du risque n'était pas significativement différente entre les patients pris en charge par des CET chirurgiens et non-chirurgiens (RC 0,92, IC à 95 % 0,80 à 1,06, p = 0,23). De plus, nous ne pouvons pas observer de différences de mortalité ajustée au risque pour aucun des sous-groupes évalués. CONCLUSIONS: Après avoir ajusté du risque, il n'y avait pas de différence de mortalité entre les patients traumatisés traités par des chirurgiens ou non chirurgiens CET. Notre étude soutient les médecins d'urgences jouent le rôle de CET dans les centres de traumatologie de niveau 1.

Titratable partial aortic occlusion: Extending Zone I endovascular occlusion times.

BACKGROUND: Extending the time to definitive hemorrhage control in noncompressible torso hemorrhage (NCTH) is of particular importance in the battlefield where transfer times are prolonged and NCTH remains the leading cause of death. While resuscitative endovascular balloon occlusion of the aorta is widely practiced as an initial adjunct for the management of NCTH, concerns for ischemic complications after 30 minutes of compete aortic occlusion deters many from zone 1 deployment. We hypothesize that extended zone 1 occlusion times will be enabled by novel purpose-built devices that allow for titratable partial aortic occlusion. METHODS: This is a cross-sectional analysis describing pREBOA-PRO zone 1 deployment characteristics at seven level 1 trauma centers in the United States and Canada (March 30, 2021, and June 30, 2022). To compare patterns of zone 1 aortic occlusion, the AORTA registry was used. Data were limited to adult patients who underwent successful occlusion in zone 1 (2013-2022). RESULTS: One hundred twenty-two patients pREBOA-PRO patients were included. Most catheters were deployed in zone 1 (n = 89 [73%]) with a median zone 1 total occlusion time of 40 minutes (interquartile range, 25-74). A sequence of complete followed by partial occlusion was used in 42% (n = 37) of zone 1 occlusion patients; a median of 76% (interquartile range, 60-87%) of total occlusion time was partial occlusion in this group. As was seen in the prospectively collected data, longer median total occlusion times were observed in the titratable occlusion group in AORTA compared with the complete occlusion group. CONCLUSION: Longer zone 1 aortic occlusion times seen with titratable aortic occlusion catheters appear to be driven by the feasibility of controlled partial occlusion. The ability to extend safe aortic occlusion times may have significant impact to combat casualty care where exsanguination from NCTH is the leading source of potentially preventable deaths. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

Self-propelling thrombin powder enables hemostasis with no observable recurrent bleeding or thrombosis over 3 days in a porcine model of upper GI bleeding.

BACKGROUND AND AIMS: Hemostatic powders used to manage upper GI bleeding continue to exhibit high recurrent bleeding rates. Previously, self-propelling thrombin powder (SPTP) sprayed endoscopically managed severe Forrest class 1A bleeding. Here, we evaluate SPTP in a 3-day recovery model of diffuse ulcerated bleeding. METHODS: Five anesthetized pigs underwent an endoscopic mucosal snare resection to trigger diffuse ulcer bleeding and were treated with SPTP. The time to hemostasis and the amount of powder delivered were measured. Pigs were recovered and monitored. RESULTS: Five pigs achieved hemostasis in 4.5 ± 1.2 minutes At 3 days after the procedure, the pigs were rescoped and showed no recurrent bleeding. Measured blood parameters were not significantly different from baseline. There were no signs of foreign bodies or thromboembolism during gross necropsy and histopathology of key organs. CONCLUSIONS: SPTP is a promising novel material that stopped diffuse ulcer bleeding in 5 pigs without recurrent bleeding or adverse local or systemic events.

Virtual trauma patient simulation design using the McGill Simulation Complexity Score (MSCS): a breakthrough in trauma education.

BACKGROUND: Virtual patient simulations are interactive, computer-based cases. We designed scenarios based on the McGill Simulation Complexity Score (MSCS), a previously described objective complexity score. We aimed to establish validity of the MSCS and introduce a novel learning tool in trauma education at our institution. METHODS: After design of an easy and difficult patient scenario, we randomized medical students and residents to each perform 1 of the 2 scenarios. We conducted a 2-way analysis of variance of training level (medical student, resident) and scenario complexity (easy, difficult) to assess their effects on virtual time, the number of steps taken in the scenario, beneficial and harmful actions, and the ratio of beneficial over harmful actions. RESULTS: Virtual patient scenarios were successfully designed using the MSCS. Twenty-four medical students and 12 residents participated in the easy scenario (MSCS = 3), and 27 medical students and 12 residents did the difficult scenario (MSCS = 18). Though beneficial actions were similar between students and residents, sudents performed more harmful actions, particularly when the scenario was difficult. One virtual patient died in the easy scenario and 3 died in the difficult one (all medical students). Performance varied with level of complexity and there was significant interaction between level of training and number of steps, as well as with number of harmful actions. Decreasing performance with increasing level of complexity, as defined by the MSCS, suggests this score can accurately quantify difficulty. CONCLUSION: We established validity of the MSCS and showed its successful application on virtual patient scenario design.

Artificial intelligence and machine learning for hemorrhagic trauma care.

Artificial intelligence (AI), a branch of machine learning (ML) has been increasingly employed in the research of trauma in various aspects. Hemorrhage is the most common cause of trauma-related death. To better elucidate the current role of AI and contribute to future development of ML in trauma care, we conducted a review focused on the use of ML in the diagnosis or treatment strategy of traumatic hemorrhage. A literature search was carried out on PubMed and Google scholar. Titles and abstracts were screened and, if deemed appropriate, the full articles were reviewed. We included 89 studies in the review. These studies could be grouped into five areas: (1) prediction of outcomes; (2) risk assessment and injury severity for triage; (3) prediction of transfusions; (4) detection of hemorrhage; and (5) prediction of coagulopathy. Performance analysis of ML in comparison with current standards for trauma care showed that most studies demonstrated the benefits of ML models. However, most studies were retrospective, focused on prediction of mortality, and development of patient outcome scoring systems. Few studies performed model assessment via test datasets obtained from different sources. Prediction models for transfusions and coagulopathy have been developed, but none is in widespread use. AI-enabled ML-driven technology is becoming integral part of the whole course of trauma care. Comparison and application of ML algorithms using different datasets from initial training, testing and validation in prospective and randomized controlled trials are warranted for provision of decision support for individualized patient care as far forward as possible.

Bariatric Surgery Should Be Offered to Active-Duty Military Personnel: a Retrospective Study of the Canadian Armed Forces' Experience.

PURPOSE: Like most Western armies, obesity affects Canadian Armed Forces (CAF) personnel. Bariatric surgery is an effective treatment for obesity. However, this is not yet accepted for active-duty soldiers in most countries. The CAF have approved bariatric surgery since 2005. Our aim is to assess weight loss, resolution of obesity-related comorbidities, and impacts of bariatric surgery on military careers. MATERIALS AND METHODS: We retrospectively reviewed the perioperative data, long-term bariatric results, and military outcomes of 108 CAF active-duty military personnel who underwent bariatric surgery in Canada over a 61-month period. RESULTS: The cohort was predominantly male (66.7%) with a mean preoperative body mass index (BMI) of 43.6 ± 5.8 kg/m2. Roux-Y gastric bypass was performed in 59 patients, sleeve gastrectomy in 29, and gastric banding in 20. All the surgeries were performed laparoscopically. The total body weight loss at the last follow-up visit was 22.5 ± 11.0%. Remission or improvement of hypertension was observed in 91.2%, diabetes in 85.7%, gastroesophageal reflux disorder (GERD) in 43.6%, sleep apnea in 43.1%, and dyslipidemia in 42.9%. One patient (0.9%) was medically released due to postoperative complications. Fifteen patients (13.9%) were deployed postoperatively. The combined deployable and possibly deployable statuses increased from 35.4% preoperatively to 47.9% postoperatively. CONCLUSION: This is the largest series of bariatric surgeries performed in active-duty military personnel. Bariatric surgery is effective and safe and improves deployability without impairing military careers. These results are relevant to the military of many industrialized countries. Bariatric surgery should be considered for all active-duty military personnel who meet surgical criteria for the treatment of obesity.

Systematic review to evaluate algorithms for REBOA use in trauma and identify a consensus for patient selection.

Background: Patient selection for resuscitative endovascular balloon occlusion of the aorta (REBOA) has evolved during the last decade. A recent multicenter collaboration to implement the newest generation REBOA balloon catheter identified variability in patient selection criteria. The aims of this systematic review were to compare recent REBOA patient selection guidelines and to identify current areas of consensus and variability. Methods: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we conducted a systematic review of clinical practice guidelines for REBOA patient selection in trauma. Published algorithms from 2015 to 2022 and institutional guidelines from a seven-center REBOA collaboration were compiled and synthesized. Results: Ten published algorithms and seven institutional guidelines on REBOA patient selection were included. Broad consensus exists on REBOA deployment for blunt and penetrating trauma patients with non-compressible torso hemorrhage refractory to blood product resuscitation. Algorithms diverge on precise systolic blood pressure triggers for early common femoral artery access and REBOA deployment, as well as the use of REBOA for traumatic arrest and chest or extremity hemorrhage control. Conclusion: Although our convenience sample of institutional guidelines likely underestimates patient selection variability, broad consensus exists in the published literature regarding REBOA deployment for blunt and penetrating trauma patients with hypotension not responsive to resuscitation. Several areas of patient selection variability reflect individual practice environments. Level of evidence: Level 5, systematic review.

Potential Access to Emergency General Surgical Care in Ontario.

Limited access to timely emergency general surgery (EGS) care is a probable driver of increased mortality and morbidity. Our objective was to estimate the portion of the Ontario population with potential access to 24/7 EGS care. Geographic information system-based network-analysis was used to model 15-, 30-, 45-, 60-, and 90-min land transport catchment areas for hospitals providing EGS care, 24/7 emergency department (ED) access, and/or 24/7 operating room (OR) access. The capabilities of hospitals to provide each service were derived from a prior survey. Population counts were based on 2016 census blocks, and the 2019 road network for Ontario was used to determine speed limits and driving restrictions. Ninety-six percent of the Ontario population (n = 12,933,892) lived within 30-min's driving time to a hospital that provides any EGS care. The availability of 24/7 EDs was somewhat more limited, with 95% (n = 12,821,747) having potential access at 30-min. Potential access to all factors, including 24/7 ORs, was only possible for 93% (n = 12,471,908) of people at 30-min. Populations with potential access were tightly clustered around metropolitan centers. Supplementation of 24/7 OR capabilities, particularly in centers with existing 24/7 ED infrastructure, is most likely to improve access without the need for new hospitals.