Fabricating the multibranch carboxyl-modified cellulose for hemorrhage control

Excessive bleeding is associated with a high mortality risk. In this study, citric acid and ascorbic acid were sequentially modified on the surface of microcrystalline cellulose (MCAA) to increase its carboxyl content, and their potential as hemostatic materials was investigated. The MCAA exhibited a carboxylic group content of 9.52 %, higher than that of citric acid grafted microcrystalline cellulose (MCA) at 4.6 %. Carboxyl functionalization of microcrystalline cellulose surfaces not only plays a fundamental role in the structure of composite materials but also aids in the absorption of plasma and stimulation of platelets. Fourier -transform infrared (FT-IR), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS) spectra confirmed that carboxyl groups were successfully introduced onto the cellulose surface. Physical properties tests indicated that the MCAA possessed higher thermal stability (Tmax = 472.2 °C) compared to microcrystalline cellulose (MCC). Additionally, in vitro hemocompatibility, cytotoxicity and hemostatic property results demonstrated that MCAA displayed good biocompatibility (hemolysis ratio <1 %), optimal cell compatibility (cell viability exceeded 100 % after 72 h incubation), and impressive hemostatic effect (BCIMCAA = 31.3 %). Based on these findings, the hemostatic effect of covering a wound with MCAA was assessed, revealing enhanced hemostatic properties using MCAA in tail-amputation and liver-injury hemorrhage models. Furthermore, exploration into hemostatic mechanisms revealed that MCAA can significantly accelerate coagulation through rapid platelet aggregation and activation of the clotting cascade. Notably, MCAA showed remarkable biocompatibility and induced minimal skin irritation. In conclusion, the results affirmed that MCAA is a safe and potentially effective hemostatic agent for hemorrhage control.

Non-compressible truncal and junctional hemorrhage: A retrospective analysis quantifying potential indications for advanced bleeding control in Dutch trauma centers

BACKGROUND

Truncal and junctional hemorrhage is the leading cause of potentially preventable deaths in trauma patients. To reduce this mortality, the application of advanced bleeding control techniques, such as resuscitative endovascular balloon occlusion of the aorta (REBOA), junctional tourniquets, Foley catheters, or hemostatic agents should be optimized. This study aimed to identify trauma patients with non-compressible truncal and junctional hemorrhage (NCTJH) who might benefit from advanced bleeding control techniques during initial trauma care. We hypothesized that there is a substantial cohort of Dutch trauma patients that can possibly benefit from advanced bleeding control techniques.

METHODS

Adult trauma patients with an Abbreviated Injury Scale ≥3 in the torso, neck, axilla, or groin region, who were presented between January 1st, 2014 and December 31st, 2018 to two Dutch level-1 trauma centers, were identified from the Dutch Trauma Registry. Potential indications for advanced bleeding control in patients with NCTJH were assessed by an expert panel of three trauma surgeons based on injury characteristics, vital signs, response to resuscitation, and received treatment.

RESULTS

In total, 1719 patients were identified of whom 249 (14.5 %) suffered from NCTJH. In 153 patients (60.6 %), hemorrhagic shock could have been mitigated or prevented with advanced bleeding control techniques. This group was younger and more heavily injured: median age of 40 versus 48 years and median ISS 33 versus 22 as compared to the entire cohort. The mortality rate in these patients was 31.8 %. On average, each of the included level-1 trauma centers treated an NCTJH patient every 24 days in whom a form of advanced bleeding control could have been beneficial.

CONCLUSIONS

More than half of included Dutch trauma patients with NCTJH may benefit from in-hospital application of advanced bleeding control techniques, such as REBOA, during initial trauma care. Widespread implementation of these techniques in the Dutch trauma system may contribute to reduction of mortality and morbidity from non-compressible truncal and junctional hemorrhage.

A peptide-engineered alginate aerogel with synergistic blood-absorbing and platelet-binding capabilities to rapidly stop bleeding

Polysaccharide matrix infused with hemostasis-stimulating chemistry represents a critical medical need of bleeding management. Herein, we describe the development of a polysaccharide-peptide conjugate platform, an alginate engineered with fibrinogen-derived platelet-binding peptides (APE). The alginate backbone was found to allow for multivalent grafting of the peptides. Processing APE conjugate into crosslinked aerogels promoted platelet accumulation, leading to a significant reduction in the coagulation time of whole rabbit blood and improving the stability of the formed clot. The APE aerogels also exhibited a high porosity and fluid uptake capacity (>90 in weight ratio) as well as good biocompatibility in hemostasis. Furthermore, in vivo studies conducted in rat models of tail cut and hepatic hemorrhage showed that APE aerogels reduced bleeding time by >58 % and blood loss by >61 %. The platelet-enrichment capacity of the APE construct synergized by high absorbency in its aerogel form offers a prototype for customized polysaccharide hemostats.

Knowledge of stop the bleed techniques- a national survey

OBJECTIVE

This article presents the dataset titled "Do you know how to Stop The Bleed®? [1]" The dataset contains the survey responses of 200 US persons aged 16 years and above regarding their knowledge of hemorrhage control, based on the American College of Surgeons Stop The Bleed® (STB) course [2].

RESULTS

Two hundred adults in the United States completed this web-based survey, which consisted of a quiz to assess STB knowledge. Factors that were not statistically correlated to STB knowledge retention included age, sex, race and education level up to college level. On the other hand, resuscitation coursework (p = 0.004) and income (p = 0.049) were important determinants of Stop the Bleed® knowledge. In particular, participants with CPR certification (p = 0.020) and/or a postgraduate degree (p = 0.015) scored higher than their counterparts in this sample cohort.

The forgotten cohort-lessons learned from prehospital trauma death: a retrospective cohort study

BACKGROUND

Trauma related deaths remain a relevant public health problem, in particular in the younger male population. A significant number of these deaths occur prehospitally without transfer to a hospital. These patients, sometimes termed "the forgotten cohort", are usually not included in clinical registries, resulting in a lack of information about prehospitally trauma deaths. The aim of the present study was to compare patients who died prehospital with those who sustained life-threatening injuries in order to analyze and potentially improve prehospital strategies.

METHODS

This cohort study included all primary operations carried out by Switzerland's largest helicopter emergency medical service (HEMS) between January 1, 2011, and December 31, 2021. We included all adult trauma patients with life-threatening or fatal conditions. The outcome of this study is the vital status of the patient at the end of mission, i.e. fatal or life-threatening. Injury, rescue characteristics, and interventions of the forgotten trauma cohort, defined as patients with a fatal injury (NACA score of VII), were compared with life-threatening injuries (NACA score V and VI).

RESULTS

Of 110,331 HEMS missions, 5534 primary operations were finally analyzed, including 5191 (93.8%) life-threatening and 343 (6.2%) fatal injuries. More than two-thirds of patients (n = 3772, 68.2%) had a traumatic brain injury without a significant difference between the two groups (p > 0.05). Thoracic trauma (44.6% vs. 28.7%, p < 0.001) and abdominal trauma (22.2% vs. 16.1%, p = 0.004) were more frequent in fatal missions whereas pelvic trauma was similar between the two groups (13.4% vs. 12.9%, p = 0.788). Pneumothorax decompression rate (17.2% vs. 3.7%, p < 0.001) was higher in the forgotten cohort group and measures for bleeding control (15.2% vs. 42.7%, p < 0.001) and pelvic belt application (2.9% vs. 13.1% p < 0.001) were more common in the life-threating injury group.

CONCLUSION

Chest decompression rates and measures for early hemorrhage control are areas for potential improvement in prehospital care.

An improved blood hemorrhaging treatment using diatoms frustules, by alternating Ca and light levels in cultures

Hemorrhage control requires hemostatic materials that are both effective and biocompatible. Among these, diatom biosilica (DBs) could significantly improve hemorrhage control, but it induces hemolysis (the hemolysis rate > 5%). Thus, the purpose of this study was to explore the influence of Ca2+ biomineralization on DBs for developing fast hemostatic materials with a low hemolysis rate. Here, CaCl2 was added to the diatom medium under high light (cool white, fluorescent lamps, 67.5 µmol m-2 s-1), producing Ca-DBs-3 with a particle size of 40-50 μm and a Ca2+ content of Ca-DBs-3 obtained from the higher concentration CaCl2 group (6.7 mmol L-1) of 0.16%. The liquid absorption capacity of Ca-DBs-3 was 30.43 ± 0.57 times its dry weight; the in vitro clotting time was comparable to QuikClot® zeolite; the hemostatic time and blood loss using the rat tail amputation model were 36.40 ± 2.52 s and 0.39 ± 0.12 g, which were 40.72% and 19.50% of QuikClot® zeolite, respectively. Ca-DBs-3 showed no apparent toxicity to L929 cells (cell viability > 80%) and was non-hemolysis (the hemolysis rate < 2%). This study prepared Ca-DBs-3 with a rapid hemostatic effect and good biocompatibility, providing a path to develop diatom biosilica hemostatic materials.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42995-023-00180-3.

[The chapters "Stop the bleed-prehospital" and "Coagulation management and volume therapy (emergency departement)" in the new S3 guideline "Polytrauma/severe injury treatment"]

The S3 guideline on the treatment of patients with severe/multiple injuries by the German Association of the Scientific Medical Societies was updated between 2020 and 2022. This article describes the essence of the new chapter "Stop the bleed-prehospital" and the revised chapter "Coagulation management and volume therapy".

Angioembolization in Severe Pelvic Trauma is Associated with Venous Thromboembolism

INTRODUCTION

Management of hemorrhage from pelvic fractures is complex and requires multidisciplinary attention. Pelvic angioembolization (AE) has become a key intervention to aid in obtaining definitive hemorrhage control. We hypothesized that pelvic AE would be associated with an increased risk of venous thromboembolism (VTE).

METHODS

All adults (age >16) with a severe pelvic fracture (Abbreviated Injury Scale ≥ 4) secondary to a blunt traumatic mechanism in the 2017-2019 American College of Surgeons Trauma Quality Improvement Program database were included. Patients who did not receive VTE prophylaxis during their admission were excluded. Patients who underwent pelvic AE during the first 24 h of admission were compared to those who did not using propensity score matching. Matching was performed based on patient demographics, admission physiology, comorbidities, injury severity, associated injuries, other hemorrhage control procedures, and VTE prophylaxis type, and time to initiation of VTE prophylaxis. The rates of VTE (deep vein thrombosis and pulmonary embolism) were compared between the matched groups.

RESULTS

Of 72,985 patients with a severe blunt pelvic fracture, 1887 (2.6%) underwent pelvic AE during the first 24 h of admission versus 71,098 (97.4%) who did not. Pelvic AE patients had a higher median Injury Severity Score and more often required other hemorrhage control procedures, with laparotomy being most common (24.7%). The median time to initiation of VTE prophylaxis in pelvic AE versus no pelvic AE patients was 60.1 h (interquartile range = 36.6-98.6) versus 27.7 h (interquartile range = 13.9-52.4), respectively. After propensity score matching, pelvic AE patients were more likely to develop VTE compared to no pelvic AE patients (11.8% versus 9.5%, P = 0.03).

CONCLUSIONS

Pelvic AE for control of hemorrhage from severe pelvic fractures is associated with an increased risk of in-hospital VTE. Patients who undergo pelvic AE are especially high risk for VTE and should be started as early as safely possible on VTE prophylaxis.

Sprayable surface-adaptive biocompatible membranes for efficient hemostasis via assembly of chitosan and polyphosphate

This work describes a hemostatic membrane system (or surface coating) based on spray-assisted layer-by-layer electrostatic assemblies of oppositely charged polyphosphate (polyP) and chitosan (Cs). The as-prepared membrane formed a robust micro-stratified porous structure with high flexibility. Both blood clotting test and rodent hepatic severe hemorrhage model revealed the excellent hemostatic performance of the membrane system, benefitting from the robust assembly and synergistic effect of polyP/Cs as well as membrane surface chemistry. Compared to Cs-topped membrane surface, polyP-sprayed one exhibited further improved hemostatic effect via promoting fibrin formation. Besides, comprehensive in vitro and in vivo evaluations demonstrated good biocompatibility and biodegradability of the membrane. The present approach that integrated the hemostasis-stimulating capability of polyP/Cs with facile spraying method is highly scalable and flexible, which is envisioned to be adapted readily for other hemostatic polyelectrolytes and surface functionalization of diverse existing hemostatic products on demand.

Smarter faster just-in-time hemorrhage control: A pilot evaluation of remotely piloted aircraft system delivered STOP-THE-BLEED equipment with just-in-time remote telementored deployment

Introduction

Remotely Piloted Aircraft Systems (RPAS) can access patients inaccessible to traditional rescue. Just-in-time remote telementoring (RTM) of naïve users to self-care could potentially address challenges in salvaging exsanguination in remote environments.

Methods

An exsanguination self-application task was established in a wilderness location. Three volunteers-initiated distress calls to prompt RPAS precision delivered STOP-THE-BLEED kits, after which a remote mentor directed the volunteers how to self-care.

Results

Limited connectivity prevented video, however each volunteer delivered images and initiated conversation with the mentor pre-RPAS arrival. Thereafter, all subjects were able to unpack and deploy hemorrhage control adjuncts under verbal direction, and to simulate self-application. All subjects were able to successfully apply wound-clamps, tourniquets, and pack wounds although one had insufficient pressure.

Discussion

RPASs can deliver supplies long before human rescuers, and communication connectivity might allow remote mentoring in device application. Further development of technology and self-care paradigms for exsanguination are encouraged.

PEG-mediated hybrid hemostatic gauze with in-situ growth and tightly-bound mesoporous silicon

Pre-hospital control of bleeding is critical to save lives, however the development of hemostatic agents with efficient and safe performance is still a challenge. In this study, a hybrid hemostatic gauze (MG-PEG) with in-situ growth and tightly bound mesoporous silicon (MSN) was prepared by template method for hemorrhage control. This material integrated meso-porosity, blood coagulation and stability into flexible gauze fiber. The PEG in MG-PEG was not only used as template for the in-suit MSN growth, but also acted as joint connection between the gauze fibers and MSN. The MSN particles were firmly bound to the surface of gauze fibers with extremely low leakage after 3 min of sonication and displayed a comparable coagulant activity to untreated sample. The results of animal experiments confirmed that MG-PEG possessed superior hemostatic performance over silicates-based inorganic hemostasis-Combat Gauze, in terms of higher coagulant activity (in vivo clotting time <200 s), minimized loss of active components (liquids OD was only 3 % of CG), well biocompatibility (hemolysis ratio < 5 %, no cytotoxicity) and wider indications range for practical application.

Traction Splinting for midshaft femoral fractures in the pre-hospital and Emergency Department environment-A systematic review

INTRODUCTION

Pain and hemorrhage are common in midshaft femoral fractures. Traction splints (TSs) can reduce pain and control hemorrhage, but evidence of their effectiveness in femoral fractures is still lacking. Through a systematic review, we aimed to analyze and discuss the potential role of TSs in the prehospital and emergency department (ED) setting.

METHODS

The Embase, CINAHL, Cochrane, and PubMed databases were searched up to January 2022. All studies on femoral fractures in the prehospital or ED setting that compared TSs with immobilization or no intervention were included. Articles not written in English, German, or Dutch were excluded. Two authors screened all articles, assessed their quality, and included them if both agreed on their inclusion. The risk of bias was assessed using the modified Methodological Index for Non-Randomized Studies (MINORS). The primary outcome measures were pain and hemorrhage control, while the secondary outcome measures were survivability, morbidity, and complications.

RESULTS

A total of 1,248 articles matched the search strategy, 24 articles were assessed for eligibility based on their abstracts, resulting in 20 articles being included in the synthesis. Ten articles reviewed the effects of TSs on pain, while five reported that the use of a TS was appropriate. All five articles that reviewed blood loss found benefits from the use of a TS. One study found significantly fewer pulmonary complications in patients who were splinted earlier at the scene of injury (level III). No difference was found in complications or mortality between prehospital patients receiving a TS or no TS (level III). None of the studies noted that TSs were a necessity in the ED setting; however, some argued that a TS is a necessary and useful prehospital tool in rural or military areas.

CONCLUSION

TS use is associated with a decreased necessity for blood transfusions and fewer pulmonary complications. No favorable effects were found in terms of pain relief. We recommend the use of TSs in situations where one is likely to encounter a femoral fracture as well as when the time to definitive treatment is long. Further well-designed studies are required to validate these recommendations.

Management of high-energy blunt pelvic ring injuries: A retrospective cohort study evaluating an institutional protocol

INTRODUCTION

High-energy blunt pelvic ring injuries with hemodynamic instability are complicated by a high mortality rate (up to 32%). There is no consensus on the best management strategy for these injuries. The aim of this study was to evaluate the high-energy blunt pelvic ring injury management protocol implemented in the authors' institution.

PATIENTS AND METHODS

This retrospective cohort study was performed in an academic level I trauma center. The institutional protocol incorporates urgent pelvic mechanical stabilization of hemodynamically unstable patients not responding to a pelvic belt, fluids, and transfusions. If hemodynamic instability persists, angiography ± embolization is performed. Adult patients sustaining a high-energy blunt pelvic ring injury between 2014.01.01 and 2019.12.31 were included in the study. The primary outcome was mortality at 1, 2, 30 and 60 days. The secondary outcomes were the number of packed red blood cell units transfused during the first 24 h, intensive care unit stay, and total hospitalization length of stay.

RESULTS

192 high-energy blunt pelvic ring injury patients were analyzed. Of these, 71 (37%) were hemodynamically unstable, and 121 (63%) were stable. The overall in-hospital mortality of the hemodynamically unstable and stable groups was 20/71 (28.2%) and 4/121 (3.3%) respectively (p<0.001). Cumulative mortality rates for hemodynamically unstable patients were 15.5% at day 1, 16.9% at day 2, 26.8% at day 30 and 28.2% at day 60, and for hemodynamically stable patients, rates were 0% at day 1 and 2, 2.5% at day 30 and 3.3% at day 60. Unstable patients required a higher number of packed red blood cell units than stable patients during the first 24 h (5.1 vs. 0.1; p<0.001). Intensive care unit length of stay and total hospitalization duration was 11.25 and 37.4 days for unstable patients and 1.9 and 20.9 days for stable patients (p<0.001).

CONCLUSIONS

For both hemodynamically unstable and stable patients, the institutional protocol showed favorable mortality rates when compared to available literature. Comparative studies are needed to determine the management strategies with the best clinical outcome and survival.

Supramolecularly functionalized platelets for rapid control of hemorrhage

Excessive bleeding has always been of great medical challenge, particularly in trauma and surgery. Due to the fast clearance of medicine and complex hemodynamics during hemorrhage, it is often difficult to achieve rapid and effective hemostasis on irregularly shaped, noncompressible visceral bleeding wounds. Herein, we report a hemostatic derived from supramolecularly functionalized platelets (SPLTs), showing rapid hemorrhage controlling effects via efficiently targeting injured vessels and in-situ aggregation. Von Willebrand factor-binding peptide (VBP) modified hyaluronic acid (HA-VBP) decorated platelets (PLTs) were fabricated via supramolecular host-guest interactions between cucurbit[7]uril (CB[7], a host molecule) modified on HA-VBP (HA-CB[7]-VBP) and adamantane (ADA, a guest molecule) anchored on the surface of PLTs (ADA-PLTs). The SPLTs demonstrated approximately 10-fold improvements than the native PLTs in the targeting efficiency into the injured vessels in mice upon intravenous injection. More significantly, the total bleeding time and bleeding volume were dramatically reduced down to less than 1/4 and 1/10 of the control group, respectively, in both external and internal major bleeding mice models. This SPLTs provide a facile yet effective approach for rapid control of major hemorrhage and offers important new insights to the design and development PLTs-based hemostatics. STATEMENT OF SIGNIFICANCE: Hemorrhage is one of the greatest threats to humans in trauma and surgery. To reduce bleeding volume and time, transfusion of hematological products such as platelets (PLTs)-rich plasma is one of the most commonly used therapeutics, but with low targeting and hemostatic efficiency. Thus, engineered PLTs with expanded structural repertoire and functionalities are in urgent clinical needs. Herein, we developed supramolecularly functionalized PLTs (SPLTs), prepared with a mild and facile approach, for rapid control of hemorrhage with significantly enhanced targeting efficiency. The SPLTs not only provide a facile approach for rapid control of major hemorrhage, but also offer important new insights into the development PLTs-based hemostatics.

A chitosan hydrogel sealant with self-contractile characteristic: From rapid and long-term hemorrhage control to wound closure and repair

Emergent and long-term hemorrhage control is requisite and beneficial for reducing global mortality and postoperative complications (e.g., second bleeding and adverse tissue adhesion). Despite recent advance in injectable hydrogels for hemostasis, achieving rapid gelation, strong tissue-adhesive property and stable mechanical strength under fluid physiological environment is still challenging. Herein, we developed a novel chitosan hydrogel (CCS@gel) via dynamic Schiff base reaction and mussel-inspired catechol chemistry. The hydrogel possessed high gelation rate (<10 s), strong wet adhesiveness, excellent self-healing performance and biocompatibility. More importantly, the CCS@gel exhibited saline-induced contractile performance and mechanical enhancement, promoting its mechanical property in moist internal conditions. In vivo studies demonstrated its superior hemostatic efficacy for diverse anticoagulated visceral and carotid bleeding scenarios, compared to commercialized fibrin glue. The hydrogel-treated rats survived for 8 weeks with minimal inflammation and postoperative adhesion. These results revealed that the promising CCS@gel would be a facile, efficient and safe sealant for clinical hemorrhage control.

Intentional mass-casualty incident simulation-based training: A qualitative study into nursing students' perceptions and experiences

BACKGROUND

The number of intentional mass casualty incidents (IMCI) has increased in recent years, and hemorrhage control is one of the important life-saving techniques used in these events.

OBJECTIVE

The objective of this study is to understand the perceptions and experiences of nursing students subjected to a simulated intentional mass-casualty incident after receiving a training action within their curriculum, focused on how to respond to active threats and bleeding control.

DESIGN

A qualitative phenomenological study on nursing students (n = 74) enrolled in the Nursing Care for Critical Patients course, facing a simulated IMCI in November 2019.

DATA SOURCES

A total of 7 focus groups were performed, containing 8 to 12 participants each.

FINDINGS

Participants reported a feeling of vulnerability and fear of an IMCI occurrence. Based on this context, the participants reported not knowing how to react to this type of situation, which is why training activities such as this one is seen as a way of improving participants' self-protection and safety. Likewise, a simulated IMCI is considered useful for any citizen and as a training exercise for life-saving techniques, such as hemorrhage control.

CONCLUSIONS

Training on the subject of hemorrhage control using a simulated IMCI setting could increase self-efficacy and self-control, as well as reducing feelings of fear and vulnerability. Such training intervention could be primary prevention measures of an IMCI as well as a sustainable way to train knowledge-transmitting instructors.

Protect Our Kids: a novel program bringing hemorrhage control to schools

Background

Following the shooting at Sandy Hook Elementary School, the Hartford Consensus produced the Stop the Bleed program to train bystanders in hemorrhage control. In our region, the police bureau delivers critical incident training to public schools, offering instruction in responding to violent or dangerous situations. Until now, widespread training in hemorrhage control has been lacking. Our group developed, implemented and evaluated a novel program integrating hemorrhage control into critical incident training for school staff in order to blunt the impact of mass casualty events on children.

Methods

The staff of 25 elementary and middle schools attended a 90-minute course incorporating Stop the Bleed into the critical incident training curriculum, delivered on-site by police officers, nurses and doctors over a three-day period. The joint program was named Protect Our Kids. At the conclusion of the course, hemorrhage control kits and educational materials were provided and a four-question survey to assess the quality of training using a ten-point Likert scale was completed by participants and trainers.

Results

One thousand eighteen educators underwent training. A majority were teachers (78.2%), followed by para-educators (5.8%), counselors (4.4%) and principals (2%). Widely covered by local and state media, the Protect Our Kids program was rated as excellent and effective by a majority of trainees and all trainers rated the program as excellent.

Conclusions

Through collaboration between trauma centers, police and school systems, a large-scale training program for hemorrhage control and critical incident response can be effectively delivered to schools.

[Tourniquet use in the Helicopter Emergency Medical Service : Analysis based on data of the DRF Luftrettung (German Air Rescue) in the period 2015-2020]

BACKGROUND

In 2016 the first German recommendation for the preclinical use of tourniquets was published. Currently little is known of the frequency of the use of tourniquets in the prehospital setting in Germany. This study evaluated how often a tourniquet is used in a civilian German Helicopter Emergency Medical Service (HEMS).

METHOD

After the approval of the scientific working group of the DRF Luftrettung HEMS, the electronic database (HEMSDER) of the DRF Luftrettung HEMS was analyzed for the period 2015-2020 under the abovementioned question. All patients with a tourniquet application were included in the study and a comparison was made with the total trauma cohort and a subgroup analysis between patients who additionally required airway management and patients without additional airway management in the cohort of tourniquet patients. The analysis was mainly descriptive. Parametric test (t-tests and χ²-tests) were used for group comparison.

RESULTS

During the study period 67,321 trauma patients were treated and in 866 (1.3% of all trauma patients) a tourniquet was used. The mean age of these patients was 45.9 years (±19.5 years), 710 (84%) were male, 439 (51%) suffered a monotrauma, 296 (34%) suffered multiple trauma, 339 (38%) required a prehospital airway management and 321 (37%) of these were intubated. Significant differences between patients with tourniquet application and the rest of the trauma cohort were detected in general data (monotrauma, polytrauma and high-speed trauma, massive bleeding), vital signs at the scene of the accident (GCS, HF, S_pO₂) and necessary interventions, such as pressure bandages and use of hemostyptics, tranexamic acid, analgesia, the frequency of intubation and colloidal volume replacement. Due to limitations of the data set we could not obtain information regarding the limb used for the tourniquet, whether a conversion of the tourniquet was carried out and if the tourniquet was used according to the current German trauma guidelines.

CONCLUSION

With a frequency of 1.3% the need for a prehospital tourniquet application is low in civilian trauma patients. Monotrauma with isolated extremity injuries represent about half of the patients treated with tourniquets. The other half is represented by multiple injuries or multiple trauma patients who require significantly more invasive measures, such as airway management and more complex on-scene interventions are needed. The available data do not allow any conclusions to be drawn about the location and the quality of the tourniquet application. Future documentation systems should incorporate data on the use of tourniquets, such as the location of use, indications (tactical use/massive bleeding), bleeding control achieved (yes/no) or second tourniquet necessary, conversion (yes/no) and any obvious complications.

Accuracy of training blood volume quantification using a visual estimation tool

BACKGROUND

We investigated whether the use of a specially designed visual estimation tool may improve accuracy in quantifying blood volumes related to surface spreading.

METHODS

A prospective, paired-control, single-blinded experimental study was performed at a medical university. Anesthesiologists and emergency medical personnel estimated various blood volumes on surfaces with varying absorptivity (carpet, towel, polyvinyl chloride, wooden flooring) in an experimental setting. We assessed the sensitivity of training blood volume quantification using a self-designed visual estimation tool by comparing the accuracy of visual blood volume estimations before and after practical training with the tool.

RESULTS

A total of 352 estimations by 44 participants were evaluated. Accurate estimations improved significantly from pre-training to post-training (P<0.05). The sensitivity of blood volume quantification was 33.0% after training with the visual estimation tool. Estimations did not depend on age, profession, gender or years of the estimator's professional experience.

CONCLUSIONS

Training with a visual estimation tool by professional rescuers can improve the estimation accuracy of blood volumes spread on surfaces with varying absorptivity.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) for temporization of hemorrhage in adolescent trauma patients

BACKGROUND/PURPOSE

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has emerged as an alternative technique for traumatic hemorrhage control in the adult population. The purpose of this study is to describe the details of REBOA placement in adolescent trauma patients.

METHODS

Patients 18 years of age or less who received REBOA for aortic occlusion (AO) from August 2013 to February 2017 at 2 urban tertiary care centers were included.

RESULTS

7 adolescent trauma patients received REBOA by trauma surgeons for both blunt (n = 4) and penetrating mechanisms (n = 3); mean age was 17 + 1.5 years, mean admission lactate 13.0 + 4.85 mmol/L, and mean Hgb 10.7 + 2.7 g/dL. 3 patients received REBOA through a 12Fr sheath and 4 through a 7Fr sheath. AO occurred mostly at the distal thoracic aorta (Zone I) (85.7%) and also in the distal abdominal aorta (Zone III) (14.3%). 57% of patients were in arrest with ongoing CPR at the time of REBOA. In-hospital mortality was 57%; all of these patients were in arrest at the time of REBOA, had return of spontaneous circulation (ROSC), and survived to the operating room. No complications from REBOA were identified.

CONCLUSION

REBOA appears to be feasible for use in adolescents despite their smaller caliber vessels, even with use of a 12Fr sheath. REBOA results in improved physiology and can bridge adolescent trauma patients presenting in extremis to the operating room.

TYPE OF STUDY

Treatment/therapeutic study LEVEL OF EVIDENCE: Level IV.

Stop the Bleed: Effective Training in Need of Improvement

BACKGROUND

The "Stop the Bleed" (StB) campaign aims to educate laypersons on performing bleeding control techniques in any setting that requires hemorrhage control, such as motor vehicle crashes or mass casualty incidents. Participants undergo a didactic and practical session, the latter incorporating a mannequin. We hypothesized that participants would increase content knowledge after StB participation and that the training could be improved by a more life-like bleeding modification of the mannequin.

MATERIALS AND METHODS

From July 2017 to January 2018, hospital and community members from a major metropolitan area participated in StB training. Participants provided demographic data regarding prior emergency training and were asked pre- and post-test questions (five-point Likert scale) regarding their response to hemorrhage. Individuals also evaluated the mannequin on bleeding simulation. Scores were reported as means with standard deviation or medians with interquartile ranges (IQRs) with subset analysis stratified by experience.

RESULTS

Of 402 participants, 310 provided complete data. On the composite, pre-test self-assessment, participants had a median score of 24 of 30 points (IQR 16-30). Post-testing demonstrated a statistically significant increase with a median score of 29 (IQR 25-30, P < 0.05). Subset analysis by prior emergency training (n = 102) demonstrated that both those with prior emergency training and those with no prior emergency training had significant improvement. On evaluation of the mannequin, participants reported that a more realistic model would increase their confidence in technique. Both subgroups reported that training would be enhanced if the mannequins were more realistic.

CONCLUSIONS

StB is an effective education program. Those without prior experience or training in hemorrhage cessation demonstrated the most improvement. Regardless of background, participants reported overwhelmingly that the training would be more effective if it were more realistic. Future work to design and develop cost-effective mannequins demonstrating pulsatile blood flow and cessation of hemorrhage could enable learners to actually "Stop the Bleed".

Hemostatic agents for prehospital hemorrhage control: a narrative review

Hemorrhage is the leading cause of preventable death in combat trauma and the secondary cause of death in civilian trauma. A significant number of deaths due to hemorrhage occur before and in the first hour after hospital arrival. A literature search was performed through PubMed, Scopus, and Institute of Scientific Information databases for English language articles using terms relating to hemostatic agents, prehospital, battlefield or combat dressings, and prehospital hemostatic resuscitation, followed by cross-reference searching. Abstracts were screened to determine relevance and whether appropriate further review of the original articles was warranted. Based on these findings, this paper provides a review of a variety of hemostatic agents ranging from clinically approved products for human use to newly developed concepts with great potential for use in prehospital settings. These hemostatic agents can be administered either systemically or locally to stop bleeding through different mechanisms of action. Comparisons of current hemostatic products and further directions for prehospital hemorrhage control are also discussed.

The Challenge of Implementing the "Stop the Bleed" Campaign in Latin America

BACKGROUND

Currently, several initiatives have emerged to empower the public to act as immediate responders in front of hemorrhaging victims. We aimed to evaluate the effectiveness of implementing the Stop the Bleed campaign and the association between the instructors' background and the theoretical and practical competences achieved by the participants in Latin America.

METHODS

Medical students and general surgeons taught both allied health students and nonallied health students at a local university; the training had a master class followed by a practical component and a written test, as well as tourniquet placement was tested.

RESULTS

265 individuals received the training, and data were available for 243. Of these, 126 (52.07%) were women and the median age was 21 (IQR: 20-22) years. 121 (49.79%) were trained by general surgeons (group A) and 122 (50.21%) by medical students (group B). After the training, more than 98% of all participants perceived that they would most likely be capable of aiding correctly a bleeding victim by applying direct pressure and more than 90% of them felt confident in being able to apply a tourniquet. There were no statistically significant differences among both groups when comparing their post-training competence evaluations [Theoretical test score: group A = 5 (IQR: 4-5); group B = 5 (IQR: 4-5); P = 0.41] and [Practical competency of tourniquet deployment: group A = 119 (66.39%) versus group B = 120 (65.83%); P = 0.93].

CONCLUSIONS

The Stop the Bleed campaign can be effectively implemented in Latin America, and it can be taught by prequalified medical students without altering the learning objectives of the course.

Advancing the Education of Stop the Bleed: Development of a Perfused Synthetic Cadaver Model

BACKGROUND

As active shootings and mass casualty incidents have become more prevalent, courses designed to teach basic hemorrhage control to laypersons have proliferated. Participants currently undergo Stop the Bleed (StB) training currently use a synthetic limb mannequin. In a prior survey of 88 participants, there was overwhelming sentiment that the mannequin was limited by its inability to demonstrate cessation of bleeding when hemorrhage control techniques were applied. We hypothesized that simulated bleeding that can be controlled by StB techniques would improve the mannequin and increase confidence of trainees in achieving bleeding control.

METHODS

The mannequin was redesigned to be a self-contained model mimicking bleeding, with fluid flowing from a reservoir into a latex tubing with a laceration mimicking an arterial wound. Fluid was pumped by a rubber bulb attached to the tubing and held in the instructor's hand. Twenty StB trainers conducted beta testing of the perfused mannequin. Forty participants underwent training with both old and new models and completed posttraining surveys.

RESULTS

Beta-testers reported positive feedback regarding both realism of the perfused mannequin and participants' ability to obtain bleeding control using StB techniques. Participants who trialed the mannequin reported increased awareness of the rate of blood flow out of a wound, which in turn increased their sense of urgency to achieve hemostasis.

CONCLUSIONS

In an effort to address shortcomings noted by participants in the current StB mannequin, we developed a novel perfused bleeding mannequin, which responds appropriately to various hemorrhage cessation techniques and is both high fidelity and low cost.

Application of an external fixator vascular compressor (EFVC) in the critically injured trauma patient: a novel damage control technique

Methods of controlling hemorrhage in penetrating abdominal injuries are varied, ranging from electrocautery, ligation, laparotomy sponge packing, angiography, hemostatic agents, and direct manual pressure. Unfortunately, traditional methods are sometimes unsuccessful due to the location or nature of the hemorrhage, and manual pressure cannot be held indefinitely. We describe a novel damage control technique for hemorrhage control in these situations, followed by three cases where an external fixator vascular compressor (EFVC) was used to hold continual pressure. Three patients are presented to a Level 1 trauma center following multiple ballistic injuries, all requiring emergent exploratory laparotomy. The first had a two-pin iliac crest EFVC placed during repeat exploratory laparotomy to control bleeding. The second patient had a supra-acetabular EFVC placed during initial exploratory laparotomy after emergent embolization failed to control bleeding from the L3 vertebral body. The third patient had a two-pin iliac crest EFVC placed at initial exploratory laparotomy due to uncontrollable bleeding from the sacral venous plexus and internal iliac veins. Of the three patients, two stabilized and survived, while one passed away due to multi-organ failure. We describe a novel damage control technique that may be a useful means of temporarily stemming intraabdominal bleeding that is otherwise recalcitrant to traditional hemostatic methods. Additionally, we provided a limited case series of patients who have undergone this technique to illustrate its utility and versatility. This technique is simple, fast, effective, and adaptable to a variety of circumstances that may be encountered in patients with intraabdominal bleeding recalcitrant to conventional hemorrhage control.

Hemorrhage Control Training Promotes Resilience-Associated Traits in Medical Students

OBJECTIVE

Given rising rates of physician burnout, the potential for clinical skills training programs to develop and reinforce resilience-associated traits in medical students warrants investigation. The primary objective of this study was to examine the impact of a hemorrhage control training program on resilience-associated traits (role-clarity, self-efficacy, and empowerment) in medical students. A secondary objective was to examine the differential impact of additional hands-on skills training.

DESIGN

This was a prospective study of medical students participating in an established hemorrhage control training program, utilizing pre-, mid-, and post-training questionnaires. The program included both an in-person lecture and hands-on skills training. Primary endpoints were self-reported increases in role clarity (when the hemorrhage control skills would and would not be applicable), self-efficacy (confidence in ability to use the skill), and empowerment (to act in a situation where the skill was needed).

SETTING

Harvard Medical School, Boston, Massachusetts.

PARTICIPANTS

One hundred and twenty-six Harvard Medical School students participated.

RESULTS

There was a significant increase at each stage of training in self-reported role clarity about when to apply hemorrhage control skills (p < 0.01) and when not to apply them (p < 0.01); confidence in application of the skill (p < 0.01); as well as empowerment to apply the skill when appropriate (p < 0.01).

CONCLUSIONS

Hemorrhage control training, a first response-related clinical skills program, is a promising domain for development and reinforcement of resilience-associated traits in medical students, particularly when the program includes hands-on skills training. Providing experiential learning opportunities that are designed not only for skills-specific outcomes, but also to reinforce such resilience-associated traits as role-clarity, self-efficacy, and empowerment provides an essential integrated perspective.

Defining Massive Transfusion in Civilian Pediatric Trauma With Traumatic Brain Injury

BACKGROUND

The purpose of this study was to identify an optimal definition of massive transfusion in civilian pediatric trauma with severe traumatic brain injury (TBI) METHODS: Severely injured children (age ≤18 y) with severe TBI in the Trauma Quality Improvement Program research data sets 2015-2016 that received blood products were identified. Data were analyzed using descriptive statistics, Wilcoxon rank-sum, chi-square, and logistic regression. Continuous variables are presented as median (interquartile range). Massive transfusion thresholds were determined based on receiver operating curves and optimization of sensitivity and specificity RESULTS: Of the 460 included children, the mortality rate was 43%. There were no differences in demographics, heart rate at presentation, or injury severity score between children that lived or died. However, those who died had lower Glasgow coma scores (3 [3, 8] versus 3 [3, 3]; P < 0.01), were more likely to have had a penetrating injury (20% versus 11%; P < 0.01) and were more likely to be hypotensive for age (62% versus 34%; P < 0.01). Total blood products infused were greater in those who died (34 mL/kg/4-h [17, 65] versus 22 [12, 44]; P < 0.01). Sensitivity and specificity for delayed mortality was optimized at 40 mL/kg/4 h, and for the need for a hemorrhage control procedure at 50 mL/kg/4 h. These thresholds predicted delayed mortality (OR 2.12; 95% CI 1.28-3.50; P < 0.01) and the need for hemorrhage control procedures (5.47; 95% CI 2.82-10.61; P < 0.01) CONCLUSIONS: For children with TBI, a massive transfusion threshold of 40 mL/kg/4-h of total administered blood products may be used to identify at-risk patients, improve resource utilization, and guide future research methodology.

Resuscitative Endovascular Balloon Occlusion of the Aorta: Assessing Need in an Urban Trauma Center

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) has emerged as a bridge to definitive hemostasis in select patients with noncompressible torso hemorrhage. The number of patients who might benefit from this procedure, however, remains incompletely defined. We hypothesized that we could quantify the number of patients presenting to our center over a 2-year period who may have benefited from REBOA.

METHODS

All patients presenting to our trauma center from 2014 to 2015 were included. Potential REBOA patients were identified based on anatomic injuries. We used ICD-9 codes to identify REBOA-amenable injury patterns and physiology. We excluded patients with injuries contraindicating REBOA. We then used chart review by two REBOA-experienced independent reviewers to assess each potential REBOA candidate, evaluate the accuracy of our algorithm, and to identify a cohort of confirmed REBOA candidates.

RESULTS

Four thousand eight hundred eighteen patients were included of which 666 had injuries potentially amenable to REBOA. Three hundred thirty-five patients were hemodynamically unstable, and 309 patients had contraindications to REBOA. Sixty-four patients had both injury patterns and physiology amenable to REBOA with no contraindications, and these patients were identified as potential REBOA candidates. Of these, detailed independent two physician chart review identified 29 patients (45%) as confirmed REBOA candidates (interrater reliability kappa = 0.94, P < 0.001).

CONCLUSIONS

Our database query identified patients with indications for REBOA but overestimated the number of REBOA candidates. To accurately quantify the REBOA candidate population at a given center, an algorithm to identify potential patients should be combined with chart review.

STUDY TYPE

Therapeutic study, level V.

Acute Management of the Traumatically Injured Pelvis

Severe pelvic trauma is a challenging condition. The pelvis can create multifocal hemorrhage that is not easily compressible nor managed by traditional surgical methods such as tying off a blood vessel or removing an organ. Its treatment often requires reapproximation of bony structures, damage control resuscitation, assessment for associated injuries, and triage of investigations, as well as multimodality hemorrhage control (external fixation, preperitoneal packing, angioembolization, REBOA [resuscitative endovascular balloon occlusion of the aorta]) by multidisciplinary trauma specialists (general surgeons, orthopedic surgeons, endovascular surgeons/interventional radiologists). This article explores this complex clinical problem and provides a practical approach to its management.

Penetrating Vascular Injury: Diagnosis and Management Updates

Penetrating vascular injury is becoming increasingly common in the United States and abroad. Much of the current research and treatment is derived from wartime and translation to the civilian sector has been lacking. Penetrating vascular injury can be classified as extremity, junctional, or noncompressible. Diagnosis can be obvious but at other times subtle and difficult to diagnose. Although there are numerous modalities, computed tomography angiography is the diagnostic study of choice. It is hoped that care will be improved by using an algorithmic approach integrating experience from military and civilian research.

Intra-abdominal packing with laparotomy pads and QuikClot™ during damage control laparotomy: A safety analysis

BACKGROUND

Intra-abdominal packing with laparotomy pads (LP) is a common and rapid method for hemorrhage control in critically injured patients. Combat Gauze™ and Trauma Pads™ ([QC] Z-Medica QuikClot^®) are kaolin impregnated hemostatic agents, that in addition to LP, may improve hemorrhage control. While QC packing has been effective in a swine liver injury model, QC remains unstudied for human intra-abdominal use. We hypothesized QC packing during damage control laparotomy (DCL) better controls hemorrhage than standard packing and is safe for intracorporeal use.

METHODS

A retrospective review (2011-2014) at a Level-I Trauma Center reviewed all patients who underwent DCL with intentionally retained packing. Clinical characteristics, intraoperative and postoperative parameters, and outcomes were compared with respect to packing (LP vs. LP+QC). All complications occurring within the patients' hospital stays were reviewed. A p≤0.05 was considered significant.

RESULTS

68 patients underwent DCL with packing; (LP n=40; LP+QC n=28). No difference in age, BMI, injury mechanism, ISS, or GCS was detected (Table 1, all p>0.05). LP+QC patients had a lower systolic blood pressure upon ED presentation and greater blood loss during index laparotomy than LP patients. LP+QC patients received more packed red blood cell and fresh frozen plasma resuscitation during index laparotomy (both p<0.05). Despite greater physiologic derangement in the LP+QC group, there was no difference in total blood products required after index laparotomy until abdominal closure (LP vs LP+QC; p>0.05). After a median of 2days until abdominal closure in both groups, no difference in complications rates attributable to intra-abdominal packing (LP vs LP+QC) was detected.

CONCLUSION

While the addition of QC to LP packing did not confer additional benefit to standard packing, there was no additional morbidity identified with its use. The surgeons at our institution now select augmented packing with QC for sicker patients, as we believe this may have additional advantage over standard LP packing. A randomized controlled trial is warranted to further evaluate the intra-abdominal use of advanced hemostatic agents, like QC, for both hemostasis and associated morbidity.

The effects of QuikClot Combat Gauze on hemorrhage control in the presence of hemodilution and hypothermia

Hemorrhage is the leading cause of death from trauma. Intravenous (IV) fluid resuscitation in these patients may cause hemodilution and secondary hemorrhage. In addition, hypothermia may interfere with coagulation. The purposes of this study were to compare the effectiveness QuikClot Combat Gauze (QCG) to a control group on hemorrhage in a hemodiluted, hypothermic model, and to determine the effects of IV volume resuscitation on rebleeding. This was a prospective, between subjects, experimental design. Yorkshire swine were randomly assigned to two groups: QCG (n = 13) or control (n = 13). The subjects were anesthetized. Hypothermia (temperature of ≤34.0 °C) was induced; 30% of their blood volume was exsanguinated. A 3:1 replacement of Lactated Ringer's was administered to dilute the remaining blood. The femoral artery and vein were transected. After 1 min of uncontrolled hemorrhage, QCG was placed into the wound followed by standard wound packing. The control group underwent the same procedures without QCG. After 5 min of manual pressure, a pressure dressing was applied. Following 30 min, the dressings were removed, and blood loss was calculated. For subjects achieving hemostasis, up to 5 L of IV fluid was administered or until bleeding occurred, which was defined as >2% total blood volume. The QCG had significantly less hemorrhage than the control (QCG = 30 ± 99 mL; control = 404 ± 406 mL) (p = .004). Further, the QCG group was able to tolerate more resuscitation fluid before hemorrhage (QCG = 4615 ± 1386 mL; control = 846 ± 1836) (p = .000).