Damage control resuscitation

Intravenous Hemostats: Foundation, Targeting, and Controlled-Release

Uncontrollable blood loss is the greatest cause of mortality in prehospital patients and the main source of disability and death in hospital care. Compared with external hemostats, intravenous hemostats are more appropriate for preventing and treating uncontrolled bleeding in vivo and large bleeding on the body surface. This Review initially establishes intravenous hemostats' response basis, including the coagulation mechanism, fibrinolytic pathway, and protein corona. Second, the study of advancement of intravenous hemostat targeting was expanded from two perspectives, cellular hemostatic agents and synthetic hemostatic agents. Meanwhile, after discussing the progress of controlled-release intravenous hemostats with platelets as the stimuli, this Review offers insight into the possibility of controlled-release intravenous hemostats with microenvironment as the stimuli, combining the studies of controlled-release targeted thrombolysis.

The Pathophysiology and Management of Hemorrhagic Shock in the Polytrauma Patient

The recognition and management of life-threatening hemorrhage in the polytrauma patient poses several challenges to prehospital rescue personnel and hospital providers. First, identification of acute blood loss and the magnitude of lost volume after torso injury may not be readily apparent in the field. Because of the expression of highly effective physiological mechanisms that compensate for a sudden decrease in circulatory volume, a polytrauma patient with a significant blood loss may appear normal during examination by first responders. Consequently, for every polytrauma victim with a significant mechanism of injury we assume substantial blood loss has occurred and life-threatening hemorrhage is progressing until we can prove the contrary. Second, a decision to begin damage control resuscitation (DCR), a costly, highly complex, and potentially dangerous intervention must often be reached with little time and without sufficient clinical information about the intended recipient. Whether to begin DCR in the prehospital phase remains controversial. Furthermore, DCR executed imperfectly has the potential to worsen serious derangements including acidosis, coagulopathy, and profound homeostatic imbalances that DCR is designed to correct. Additionally, transfusion of large amounts of homologous blood during DCR potentially disrupts immune and inflammatory systems, which may induce severe systemic autoinflammatory disease in the aftermath of DCR. Third, controversy remains over the composition of components that are transfused during DCR. For practical reasons, unmatched liquid plasma or freeze-dried plasma is transfused now more commonly than ABO-matched fresh frozen plasma. Low-titer type O whole blood may prove safer than red cell components, although maintaining an inventory of whole blood for possible massive transfusion during DCR creates significant challenges for blood banks. Lastly, as the primary principle of management of life-threatening hemorrhage is surgical or angiographic control of bleeding, DCR must not eclipse these definitive interventions.

Major Prehospital Trauma and In-Hospital Emergencies: Massive Transfusion Triggers

BACKGROUND

Massive transfusion (MT) in trauma is initiated on the basis of factors of different natures and depending on protocols and scales used both in prehospital and in-hospital care areas.

OBJECTIVE

The main goal was to analyze and relate factors and predictive variables for MT requirements considering both health care areas.

METHOD

This was a retrospective cohort study that included patients who were treated either at the emergency department of a large hospital or through prehospital care before arrival at the hospital. The patients included were adults who received MT, defined as a blood bank request of 10 or more units of red cells in the first 24 hours or 5 or more within 4 hours of trauma, from January 1, 2009, to January 1, 2017. The variables included were individual characteristics and those associated with the trauma, clinical-analytical assessment, resuscitation, timing, and survival.

RESULTS

A total of 52 patients who received MT were included. The average age of the patients was 41.23 ± 16.06 years, a mean of 19.56 ± 12.77 units was administered, and the mortality rate was 21.2%.

DISCUSSION

Injury mechanism, clinical-analytical variables, and resuscitation strategies have a significant influence on the need for MT; therefore, early identification is fundamental for performing quality management and addressing avoidable factors during MT processes.

Massive transfusion prediction in patients with multiple trauma by decision tree: a retrospective analysis

Early initial massive transfusion protocol and blood transfusion can reduce patient mortality, however accurately identifying the risk of massive transfusion (MT) remains a major challenge in severe trauma patient therapy. We retrospectively analyzed clinical data of severe trauma patients with and without MT. Based on analysis results, we established a MT prediction model of clinical and laboratory data by using the decision tree algorithm in patients with multiple trauma. Our results demonstrate that shock index, injury severity score, international normalized ratio, and pelvis fracture were the most significant risk factors of MT. These four indexes were incorporated into the prediction model, and the model was validated by using the testing dataset. Moreover, the sensitivity, specificity, accuracy and area under curve values of prediction model for MT risk prediction were 60%, 92%, 90% and 0.85. Our study provides an easy and understandable classification rules for identifying risk factors associated with MT that may be useful for promoting trauma management.

Hemoglobin-based Oxygen Carriers: Current State-of-the-art and Novel Molecules

In blood, the primary role of red blood cells (RBCs) is to transport oxygen via highly regulated mechanisms involving hemoglobin (Hb). Hb is a tetrameric porphyrin protein comprising of two α- and two β-polypeptide chains, each containing an iron-containing heme group capable of binding one oxygen molecule. In military as well as civilian traumatic exsanguinating hemorrhage, rapid loss of RBCs can lead to suboptimal tissue oxygenation and subsequent morbidity and mortality. In such cases, transfusion of whole blood or RBCs can significantly improve survival. However, blood products including RBCs present issues of limited availability and portability, need for type matching, pathogenic contamination risks, and short shelf-life, causing substantial logistical barriers to their prehospital use in austere battlefield and remote civilian conditions. While robust research is being directed to resolve these issues, parallel research efforts have emerged toward bioengineering of semisynthetic and synthetic surrogates of RBCs, using various cross-linked, polymeric, and encapsulated forms of Hb. These Hb-based oxygen carriers (HBOCs) can potentially provide therapeutic oxygenation when blood or RBCs are not available. Several of these HBOCs have undergone rigorous preclinical and clinical evaluation, but have not yet received clinical approval in the USA for human use. While these designs are being optimized for clinical translations, several new HBOC designs and molecules have been reported in recent years, with unique properties. The current article will provide a comprehensive review of such HBOC designs, including current state-of-the-art and novel molecules in development, along with a critical discussion of successes and challenges in this field.

The Las Vegas mass shooting: An analysis of blood component administration and blood bank donations

BACKGROUND

The deadliest mass shooting in modern United States history occurred on October 1, 2017, in Las Vegas, killing 58 and overwhelming hospitals with more than 600 injured. The scope of the tragedy offers insight into medical demands, which may help guide preparedness for future mass shooting incidents.

METHODS

Retrospective, deidentified, health care institution-provided data from all hospitals and blood banks providing care to Las Vegas shooting victims were gathered. Study authors independently reviewed all data and cross-referenced it for verification. Main outcomes and measures include the number of victims requiring hospital and intensive care admission, the amount and types of blood components transfused during the first 24 hours, and the amount of blood donated to local blood banks following the Las Vegas mass shooting.

RESULTS

Two hundred twenty patients required hospital admission, 68 of them to critical care. Nearly 500 blood components were transfused during the first 24 hours in a red blood cell-to-plasma-to-platelet ratio of 1:0.54:0.81. Public citizens donated almost 800 units of blood immediately after the shooting; greater than 17% of this donated blood went unused.

CONCLUSIONS

The amount of blood components transfused per patient admitted was similar in magnitude to other mass casualty events, and available blood supply met patient demand. The public call for blood donors was not necessary to meet immediate demand and led to resource waste. Preparation for future mass shooting incidents should include training the community in hemorrhage control, encouraging routine blood donation, and avoiding public calls for blood donation unless approved by local blood suppliers.

LEVEL OF EVIDENCE

Therapeutic study, level V.

Massive transfusion triggers in severe trauma: Scoping review

OBJECTIVE

to identify the predictive variables or the massive transfusion triggers in severely traumatized patients through the existing scales.

METHOD

a review of the literature was carried out using the Scoping Review method across the electronic databases CINAHL, MEDLINE, LILACS, the Cochrane and IBECS libraries, and the Google Scholar search tool.

RESULTS

in total, 578 articles were identified in the search and the 36 articles published in the last ten years were included, of which 29 were original articles and 7 review articles. From the analysis, scales for massive transfusion and their predictive triggers were examined.

CONCLUSION

the absence of universal criteria regarding the massive transfusion triggers in traumatized patients has led to the development of different scales, and the studies on their validation are considered relevant for the studies about when to initiate this strategy.

Optimizing transfusion strategies in damage control resuscitation: current insights

From clinical and laboratory studies of specific coagulation defects induced by injury, damage control resuscitation (DCR) emerged as the most effective management strategy for hemorrhagic shock. DCR of the trauma patient who has sustained massive blood loss consists of 1) hemorrhage control; 2) permissive hypotension; and 3) the prevention and correction of trauma-induced coagulopathies, referred to collectively here as acute coagulopathy of trauma (ACOT). Trauma patients with ACOT have higher transfusion requirements, may eventually require massive transfusion, and are at higher risk of exsanguinating. Distinct impairments in the hemostatic system associated with trauma include acquired quantitative and qualitative platelet defects, hypocoagulable and hypercoagulable states, and dysregulation of the fibrinolytic system giving rise to hyperfibrinolysis or a phenomenon referred to as fibrinolytic shutdown. Furthermore, ACOT is a component of a systemic host defense dysregulation syndrome that bears several phenotypic features comparable with other acute systemic physiological insults such as sepsis, myocardial infarction, and postcardiac arrest syndrome. Progress in the science of resuscitation has been continuing at an accelerated rate, and clinicians who manage catastrophic blood loss may be incompletely informed of important advances that pertain to DCR. Therefore, we review recent findings that further characterize the pathophysiology of ACOT and describe the application of this new information to optimization of resuscitation strategies for the patient in hemorrhagic shock.

Biomaterials and Advanced Technologies for Hemostatic Management of Bleeding

Bleeding complications arising from trauma, surgery, and as congenital, disease-associated, or drug-induced blood disorders can cause significant morbidities and mortalities in civilian and military populations. Therefore, stoppage of bleeding (hemostasis) is of paramount clinical significance in prophylactic, surgical, and emergency scenarios. For externally accessible injuries, a variety of natural and synthetic biomaterials have undergone robust research, leading to hemostatic technologies including glues, bandages, tamponades, tourniquets, dressings, and procoagulant powders. In contrast, treatment of internal noncompressible hemorrhage still heavily depends on transfusion of whole blood or blood's hemostatic components (platelets, fibrinogen, and coagulation factors). Transfusion of platelets poses significant challenges of limited availability, high cost, contamination risks, short shelf-life, low portability, performance variability, and immunological side effects, while use of fibrinogen or coagulation factors provides only partial mechanisms for hemostasis. With such considerations, significant interdisciplinary research endeavors have been focused on developing materials and technologies that can be manufactured conveniently, sterilized to minimize contamination and enhance shelf-life, and administered intravenously to mimic, leverage, and amplify physiological hemostatic mechanisms. Here, a comprehensive review regarding the various topical, intracavitary, and intravenous hemostatic technologies in terms of materials, mechanisms, and state-of-art is provided, and challenges and opportunities to help advancement of the field are discussed.

Management of an Entrapped Patient with a Field Amputation

BACKGROUND

Emergency surgical amputations are rare and resource-intensive lifesaving interventions. Most emergency medical services (EMS) lack a formal protocol to manage these high-risk but low-occurrence events. There has been limited attention in the EMS community to address this issue. Without a literature-based approach, the EMS community has been offered little guidance on managing surgical field amputations.

CASE REPORT

A 38-year-old man was terminally entrapped below the waist in an industrial auger. As a last resort, the decision to initiate a field amputation was made. We outline an adaptive strategy to address the circumstances surrounding this entrapment scenario. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: A carefully preplanned protocol may lead to increased overall survivability for entrapped patients requiring emergent field amputation. Based on the lessons learned from the outcome of this case, previous cases, and a literature review, we have devised a simplified planning tool in the form of a "LIMB" mnemonic to aid EMS services in developing their own traumatic amputation protocol (TAP). "LIMB" is an acronym for: Lists of resources and equipment, Initiate TAP checklist, Manage the extrication, and Bring the patient in. The LIMB mnemonic may also be used as a checklist to assist EMS personnel in performing a field amputation. We offer rescuers a starting point to develop their own TAP capable of being executed in their own rescue environment.

Damage Control Resuscitation for Catastrophic Bleeding

The timely recognition of shock secondary to hemorrhage from severe facial trauma or as a complication of complex oral and maxillofacial surgery presents formidable challenges. Specific hemostatic disorders are induced by hemorrhage and several extreme homeostatic imbalances may appear during or after resuscitation. Damage control resuscitation has evolved from massive transfusion to a more complex therapeutic paradigm that includes hemodynamic resuscitation, hemostatic resuscitation, and homeostatic resuscitation. Definitive control of bleeding is the principal objective of any comprehensive resuscitation scheme for hemorrhagic shock.

Tactical damage control resuscitation in austere military environments

BACKGROUND

Despite the early uses of tourniquets and haemostatic dressings, blood loss still accounts for the vast majority of preventable deaths on the battlefield. Over the last few years, progress has been made in the management of such injuries, especially with the use of damage control resuscitation concepts. The early application of these procedures, on the field, may constitute the best opportunity to improve survival from combat injury during remote operations.

DATA SOURCES

Currently available literature relating to trauma-induced coagulopathy treatment and far-forward transfusion was identified by searches of electronic databases. The level of evidence and methodology of the research were reviewed for each article. The appropriateness for field utilisation of each medication was then discussed to take into account the characteristics of remote military operations.

CONCLUSIONS

In tactical situations, in association with haemostatic procedures (tourniquet, suture, etc), tranexamic acid should be the first medication used according to the current guidelines. The use of fibrinogen concentrate should also be considered for patients in haemorrhagic shock, especially if point-of-care (POC) testing of haemostasis or shock severity is available. If POC evaluation is not available, it seems reasonable to still administer this treatment after clinical assessment, particularly if the evacuation is delayed. In this situation, lyophilised plasma may also be given as a resuscitation fluid while respecting permissive hypotension. Whole blood transfusion in the field deserves special attention. In addition to the aforementioned treatments, if the field care is prolonged, whole blood transfusion must be considered if it does not delay the evacuation.

Management of Pelvic Ring Injuries in Unstable Patients

High-energy pelvic ring injuries can represent life-threatening injuries in the polytraumatized patient, particularly when presenting with hemodynamic instability. These injuries mandate a systematic multidisciplinary approach to evaluation, and timely intervention to address hemorrhage while concomitantly addressing mechanical instability. These pelvic injuries are associated with potentially lethal hemorrhage originating from venous, arterial, and osseous sources. A thorough understanding of anatomy, radiographic findings, and initial physical examination can alert one to the presence of pelvic instability necessitating emergent treatment. The focus is on hemorrhage control, using techniques for skeletal stabilization, angiography, and open procedures to decrease mortality in this high-risk patient population.

Cardiac arrest due to massive hemorrhage from uterine adenomyosis with leiomyoma successfully treated with damage control resuscitation

Case

A 57-year-old woman was transferred to our emergency department by ambulance with cardiopulmonary arrest caused by massive genital bleeding. Cardiopulmonary resuscitation, including massive transfusion, was carried out and the return of spontaneous circulation was achieved. A giant uterine tumor was considered the source of the bleeding. Although hysterectomy was necessary to achieve definitive hemostasis, the patient was unable to tolerate the operation because of hemodynamic instability, acidosis, and coagulopathy. Therefore, we undertook vaginal gauze packing and uterine artery embolization to attain temporary hemostasis, which resulted in hemodynamic stabilization. Abdominal hysterectomy for definitive hemostasis was carried out 10 h after the embolization.

Outcome

The patient made a good post-surgical recovery without any complications.

Conclusion

In treating hemorrhagic shock due to uterine leiomyoma, damage-control resuscitation may be useful as a bridge prior to definitive hemostasis through hysterectomy.

Novel porous silica granules for instant hemostasis

Granulation is one of the most feasible methods to improve hemostatic efficacy by stabilize the capillary structure of silica particles. Its usability was improved significantly through granulation by enhancing flowability and eliminating dust.

Factors affecting survival following self-inflicted head and neck gunshot wounds: a single-centre retrospective review

Self-inflicted head and neck gunshot wounds are a common modality of suicide in the USA. This study reviewed all self-inflicted head and neck gunshot wound patients with complete records (n=157) treated at a tertiary centre between 2002 and 2012 inclusive. The associations between mortality and patient/clinical variables were evaluated with the χ(2) test or Fisher's exact test for statistical difference testing. Outcomes recorded were death (n=92, 59%), discharge to long-term care/rehabilitation (n=58, 37%), and discharge home (n=7, 4%). The majority of patients were male (86.6%) and single/separated/divorced (55.5%). The mortality rate by site, in descending order, was temporal 82%, frontal scalp 69%, submental/intraoral 30%, and neck 25%. Involvement of the central nervous system (n=127) resulted in a 70% mortality, but a lower mortality was observed among patients with an avulsion injury (P=0.025). A tracheostomy within 24h of admission was statistically associated with improved survival (P<0.001), but confounding factors were found. Multivariate analysis revealed increasing age, temporal entry site, and the severity of central nervous system involvement to be positively associated with an increased mortality.

Benefits of Initial Limited Crystalloid Resuscitation in Severely Injured Trauma Patients at Emergency Department

Background

Whether initial limited crystalloid resuscitation (LCR) benefits to all severely injured trauma patients receiving blood transfusions at emergency department (ED) is uncertain. We aimed to determine the role of LCR and its associations with packed red blood cell (PRBC) transfusion during initial resuscitation.

Methods

Trauma patients receiving blood transfusions were reviewed from 2004 to 2013. Patients with LCR (L group, defined as < 2,000 mL) and excessive crystalloid resuscitation (E group, defined as ≥ 2,000 mL) were compared separately in terms of basic demographic, clinical variables, and hospital outcomes. Logistic regression, R-square (R²), and Spearman rho correlation were used for analysis.

Results

A total of 633 patients were included. The mortality was 51% in L group and 45% in E group (P = 0.11). No statistically significant difference was found in terms of basic demographics, vital signs upon arrival at ED, or injury severity between the groups. The volume of blood transfused strongly correlated with the volume of crystalloid infused in E group (R² = 0.955). Crystalloid to PRBC (C/PRBC) ratio was 0.8 in L group and 1.3 in E group (P < 0.01). The correlations between C/PRBC and ED versus ICU versus hospital length of stay (LOS) via Spearman rho were 0.25, 0.22, and 0.22, respectively.

Conclusions

Similar outcomes were observed in trauma patients receiving blood transfusions regardless of the crystalloid infusion volume. More crystalloid infusions were associated with more blood transfusions. The C/PRBC did not demonstrate predictive value regarding mortality but might predict LOS in severely injured trauma patients.