Emerging hemorrhage control and resuscitation strategies in trauma: Endovascular to extracorporeal

Approach to traumatic cardiac arrest in the emergency department: a narrative literature review for emergency providers

BACKGROUND

Traumatic cardiac arrest (TCA) is a major contributor to mortality and morbidity in all age groups and poses a significant burden on the healthcare system. Although there have been advances in treatment modalities, survival rates for TCA patients remain low. This narrative literature review critically examines the indications and effectiveness of current therapeutic approaches in treating TCA.

METHODS

We performed a literature search in the PubMed and Scopus databases for studies published before December 31, 2022. The search was refined by combining search terms, examining relevant study references, and restricting publications to the English language. Following the search, 943 articles were retrieved, and two independent reviewers conducted a screening process.

RESULTS

A review of various studies on pre- and intra-arrest prognostic factors showed that survival rates were higher when patients had an initial shockable rhythm. There were conflicting results regarding other prognostic factors, such as witnessed arrest, bystander cardiopulmonary resuscitation (CPR), and the use of prehospital or in-hospital epinephrine. Emergency thoracotomy was found to result in more favorable outcomes in cases of penetrating trauma than in those with blunt trauma. Resuscitative endovascular balloon occlusion of the aorta (REBOA) provides an advantage to emergency thoracotomy in terms of occupational safety for the operator as an alternative in managing hemorrhagic shock. When implemented in the setting of aortic occlusion, emergency thoracotomy and REBOA resulted in comparable mortality rates. Veno-venous extracorporeal life support (V-V ECLS) and veno-arterial extracorporeal life support (V-A ECLS) are viable options for treating respiratory failure and cardiogenic shock, respectively. In the context of traumatic injuries, V-V ECLS has been associated with higher rates of survival to discharge than V-A ECLS.

CONCLUSION

TCA remains a significant challenge for emergency medical services due to its high morbidity and mortality rates. Pre- and intra-arrest prognostic factors can help identify patients who are likely to benefit from aggressive and resource-intensive resuscitation measures. Further research is needed to enhance guidelines for the clinical use of established and emerging therapeutic approaches that can help optimize treatment efficacy and ameliorate survival outcomes.

Selective aortic arch perfusion: a first-in-human observational cadaveric study

BACKGROUND

Selective aortic arch perfusion (SAAP) is a novel endovascular technique that combines thoracic aortic occlusion with extracorporeal perfusion of the brain and heart. SAAP may have a role in both haemorrhagic shock and in cardiac arrest due to coronary ischaemia. Despite promising animal studies, no data is available that describes SAAP in humans. The primary aim of this study was to assess the feasibility of selective aortic arch perfusion in humans. The secondary aim of the study was to assess the feasibility of achieving direct coronary artery access via the SAAP catheter as a potential conduit for salvage percutaneous coronary intervention.

METHODS

Using perfused human cadavers, a prototype SAAP catheter was inserted into the descending aorta under fluoroscopic guidance via a standard femoral percutaneous access device. The catheter balloon was inflated and the aortic arch perfused with radio-opaque contrast. The coronary arteries were cannulated through the SAAP catheter.

RESULTS

The procedure was conducted four times. During the first two trials the SAAP catheter was passed rapidly and without incident to the intended descending aortic landing zone and aortic arch perfusion was successfully delivered via the device. The SAAP catheter balloon failed on the third trial. On the fourth trial the left coronary system was cannulated using a 5Fr coronary guiding catheter through the central SAAP catheter lumen.

CONCLUSIONS

For the first time using a perfused cadaveric model we have demonstrated that a SAAP catheter can be easily and safely inserted and SAAP can be achieved using conventional endovascular techniques. The SAAP catheter allowed successful access to the proximal aorta and permitted retrograde perfusion of the coronary and cerebral circulation.

Prehospital Resuscitation: What Should It Be?

Prehospital resuscitation is a dynamic field now being energized by new technologies and a shift in thinking regarding intravascular resuscitation. Growing evidence discourages use of intravenous (IV) crystalloid and colloid solutions in trauma, whereas blood products, particularly whole blood, are becoming preferred. Although randomized clinical trials validating definitive resuscitative protocols are still lacking, most preclinical and clinical indicators support this approach. In addition, emerging technologies such as external and endovascular hemorrhage control devices and extracorporeal perfusion are now being used routinely, even in the prehospital setting in many countries, generating new lines of emerging investigations for trauma specialists.

Surgical Science and the Evolution of Critical Care Medicine

Surgical science has driven innovation and inquiry across adult and pediatric disciplines that provide critical care regardless of location. Surgically originated but broadly applicable knowledge has been globally shared within the pages Critical Care Medicine over the last 50 years.

Management of Hemorrhagic Shock: Physiology Approach, Timing and Strategies

Hemorrhagic shock (HS) management is based on a timely, rapid, definitive source control of bleeding/s and on blood loss replacement. Stopping the hemorrhage from progressing from any named and visible vessel is the main stem fundamental praxis of efficacy and effectiveness and an essential, obligatory, life-saving step. Blood loss replacement serves the purpose of preventing ischemia/reperfusion toxemia and optimizing tissue oxygenation and microcirculation dynamics. The "physiological classification of HS" dictates the timely management and suits the 'titrated hypotensive resuscitation' tactics and the 'damage control surgery' strategy. In any hypotensive but not yet critical shock, the body's response to a fluid load test determines the cut-off point between compensation and progression between the time for adopting conservative treatment and preparing for surgery or rushing to the theater for rapid bleeding source control. Up to 20% of the total blood volume is given to refill the unstressed venous return volume. In any critical level of shock where, ab initio, the patient manifests signs indicating critical physiology and impending cardiac arrest or cardiovascular accident, the balance between the life-saving reflexes stretched to the maximum and the insufficient distal perfusion (blood, oxygen, and substrates) remains in a liable and delicate equilibrium, susceptible to any minimal change or interfering variable. In a cardiac arrest by exsanguination, the core of the physiological issue remains the rapid restoration of a sufficient venous return, allowing the heart to pump it back into systemic circulation either by open massage via sternotomy or anterolateral thoracotomy or spontaneously after aorta clamping in the chest or in the abdomen at the epigastrium under extracorporeal resuscitation and induced hypothermia. This is the only way to prevent ischemic damage to the brain and the heart. This is accomplishable rapidly and efficiently only by a direct approach, which is a crush laparotomy if the bleeding is coming from an abdominal +/- lower limb site or rapid sternotomy/anterolateral thoracotomy if the bleeding is coming from a chest +/- upper limbs site. Without first stopping the bleeding and refilling the heart, any further exercise is doomed to failure. Direct source control via laparotomy/thoracotomy, with the concomitant or soon following venous refilling, are the two essential, initial life-saving steps.

Development of a Modular Tissue Phantom for Evaluating Vascular Access Devices

Central vascular access (CVA) may be critical for trauma care and stabilizing the casualty. However, it requires skilled personnel, often unavailable during remote medical situations and combat casualty care scenarios. Automated CVA medical devices have the potential to make life-saving therapeutics available in these resource-limited scenarios, but they must be properly designed. Unfortunately, currently available tissue phantoms are inadequate for this use, resulting in delayed product development. Here, we present a tissue phantom that is modular in design, allowing for adjustable flow rate, circulating fluid pressure, vessel diameter, and vessel positions. The phantom consists of a gelatin cast using a 3D-printed mold with inserts representing vessels and bone locations. These removable inserts allow for tubing insertion which can mimic normal and hypovolemic flow, as well as pressure and vessel diameters. Trauma to the vessel wall is assessed using quantification of leak rates from the tubing after removal from the model. Lastly, the phantom can be adjusted to swine or human anatomy, including modeling the entire neurovascular bundle. Overall, this model can better recreate severe hypovolemic trauma cases and subject variability than commercial CVA trainers and may potentially accelerate automated CVA device development.

Emergency department thoracotomy in a physician-staffed trauma system: the experience of a French Military level-1 trauma center

PURPOSE

To investigate survival after emergency department thoracotomy (EDT) in a physician-staffed emergency medicine system.

METHODS

This single-center retrospective study included all in extremis trauma patients who underwent EDT between 2013 and 2021 in a military level 1 trauma center. CPR time exceeding 15 minutes for penetrating trauma of 10 minutes for blunt trauma, and identified head injury were the exclusion criteria.

RESULTS

Thirty patients (73% male, 22/30) with a median age of 42 y/o [27-64], who presented mostly with polytrauma (60%, 18/30), blunt trauma (60%, 18/30), and severe chest trauma with a median AIS of 4 3-5 underwent EDT. Mean prehospital time was 58 min (4-73). On admission, the mean ISS was 41 29-50, and 53% (16/30) of patients had lost all signs of life (SOL) before EDT. On initial work-up, Hb was 9.6 g/dL [7.0-11.1], INR was 2.5 [1.7-3.2], pH was 7.0 [6.8-7.1], and lactate level was 11.1 [7.0-13.1] mmol/L. Survival rates at 24 h and 90 days after penetrating versus blunt trauma were 58 and 41% versus 16 and 6%, respectively. If SOL were present initially, these values were 100 and 80% versus 22 and 11%.

CONCLUSION

Among in extremis patients supported in a physician-staffed emergency medicine system, implementation of a trauma protocol with EDT resulted in overall survival rates of 33% at 24 h and 20% at 90 days. Best survival was observed for penetrating trauma or in the presence of SOL on admission.

Emergency preservation and resuscitation for cardiac arrest from trauma

Patients who suffer a cardiac arrest from trauma rarely survive. Surgical control of hemorrhage cannot be obtained in time to prevent irreversible organ damage. Emergency preservation and resuscitation (EPR) was developed to utilize hypothermia to buy time to achieve hemostasis and allow delayed resuscitation. Large animal studies have demonstrated that cooling to tympanic membrane temperature 10 °C during exsanguination cardiac arrest can allow up to 2 h of circulatory arrest and repair of simulated injuries with normal neurologic recovery. The Emergency Preservation and Resuscitation for Cardiac Arrest from Trauma (EPR-CAT) trial is testing the feasibility and safety of initiating EPR. Study subjects include patients with penetrating trauma who lose a pulse within 5 minutes of hospital arrival and remain pulseless despite standard care. EPR is initiated via an intra-aortic flush of ice-cold saline solution. Following hemostasis, delayed resuscitation and rewarming are accomplished with cardiopulmonary bypass. The primary outcome is survival to hospital discharge without significant neurologic deficits. If trained team members are available, subjects can undergo EPR. If not, subjects can be enrolled as concurrent controls. Ten EPR and 10 control subjects will be enrolled. If successful, EPR could save the lives of trauma patients who are currently dying from exsanguinating hemorrhage.

Cardiopulmonary Resuscitation and Rescue Therapies

The history of cardiopulmonary resuscitation and the Society of Critical Care Medicine have much in common, as many of the founders of the Society of Critical Care Medicine focused on understanding and improving outcomes from cardiac arrest. We review the history, the current, and future state of cardiopulmonary resuscitation.

State-of-the-art methods for the treatment of severe hemorrhagic trauma: selective aortic arch perfusion and emergency preservation and resuscitation-what is next?

Trauma is a primary cause of death globally, with non‐compressible torso hemorrhage constituting an important part of “potentially survivable trauma death.” Resuscitative endovascular balloon occlusion of the aorta has become a popular alternative to aortic cross‐clamping under emergent thoracotomy for non‐compressible torso hemorrhage in recent years, however, it alone does not improve the survival rate of patients with severe shock or traumatic cardiac arrest from non‐compressible torso hemorrhage. Development of novel advanced maneuvers is essential to improve these patients’ survival, and research on promising methods such as selective aortic arch perfusion and emergency preservation and resuscitation is ongoing. This review aimed to provide physicians in charge of severe trauma cases with a broad understanding of these novel therapeutic approaches to manage patients with severe hemorrhagic trauma, which may allow them to develop lifesaving strategies for exsanguinating trauma patients. Although there are still hurdles to overcome before their clinical application, promising research on these novel strategies is in progress, and ongoing development of synthetic red blood cells and techniques that reduce ischemia‐reperfusion injury may further maximize their effects. Both continuous proof‐of‐concept studies and translational clinical evaluations are necessary to clinically apply these hemostasis approaches to trauma patients.