EVALUATION AND TREATMENT

INITIAL RESUSCITATION

These casualties typically arrive in extremis shortly after injury. Due to the severity of injury and exsanguinating hemorrhage, DCBI casualties with long field/transport times, particularly with no access to prehospital whole blood will likely die prior to arrival to the Role 2 or Role 3 medical treatment facility (MTF). Tourniquets (TQs) should be in place on all injured extremities. If the TQs are not in place, the extremities will rarely be significantly bleeding secondary to profound hemorrhagic shock. These casualties might arrive with a sternal or humeral head Intraosseous (IO) in place. Blood must be transfused through these access portals immediately, if it is not already being transfused. One challenge to the MTF provider is that IOs frequently get dislodged during transport. Do not rely solely on the IO. A large bore resuscitation line should be placed in the neck or an uninjured upper extremity. The best resuscitation line to place is the one that can be placed the fastest. Every minute matters in these casualties and the faster blood can be transfused though a central line or large bore IV (or rapid infusion catheter) the better the chance of survival.

#### Initial Evaluation & Treatment

T – Tourniquets (TQ) on all injured extremities for hemorrhage control, pelvic binder for unstable pelvis –assess TQ effectiveness frequently

A – Access – Reliable Intravenous access for resuscitation – large bore (16 Ga or larger) IVs or supradiaphragmatic central venous access (8.5Fr cordis)

R – Resuscitate with blood - massive transfusion protocol – 8 units whole blood per above the knee amputation

O – Operative intervention

- Obtain proximal vascular control
- Orthopedic Intervention – pelvic stabilization, control extremity bleeding, debride devitalized tissue, remove gross contamination
- Ongoing Resuscitation – continue blood transfusion, obtain blood gases

T – Temporize at index operation, damage control surgery only, shunt injured vessels to restore flow, temporary abdominal closure

Take back to OR planning – second debridement within 24 hours

This injury pattern mandates immediate activation of massive transfusion protocol with the preferential use of whole blood and no crystalloid as part of the resuscitation. If there is prior notification of a DCBI casualty, warm whole blood should be ready to transfuse on a rapid transfuser (Belmont or Level 1) prior to the casualty arriving. A good starting formula for transfusion requirement is 8 units of whole blood for each above knee amputation (AKA). Thus, a casualty with bilateral AKAs should have 16 units of whole blood, or 16 red blood cells (RBCs), 16 fresh frozen plasma, and 3 units of platelets ready to transfuse in the first 60 minutes of presentation. Teams that do not have this blood supply should activate the WBB. If the casualty’s blood type can be tested and there is the appropriate manpower and administrative support, then a type-specific WBB should be activated. If there are multiple casualties or if the recipient’s blood type is not known, then a LTOWB WBB should be activated.

Data from the DoDTR on 385 casualties from 2010-2021 with bilateral lower extremity amputations secondary to DCBI were transfused an average of 45 units of blood in the first 24 hours, with the highest volume of blood recorded in a survivor from this injury being over 200 units of blood product. This underscores the imperative that massive (>10 units of PRBCs/WB in 24 hours) and ultra-massive transfusion (>20 units of PRBCs/WB in 24 hours) are necessary for these casualties to survive.

These casualties are resource intensive, and time to resuscitation is critical if they are to survive. While it is understood at the time of the update of this clinical practice guidance (CPG), that the DOD is preparing for large scale combat operations (LSCO), if during the next conflict, multiple DCBI casualties are generated daily, the resources required to care for these casualties will test every aspect of the trauma system including field care and evacuation, blood supply, OR resources, personnel resources, and the movement from the theater of operations. This CPG outlines the optimal clinical management of these patients with the understanding that one of these patients will keep many providers in a well-equipped Role 3 busy for hours. The reality of the number of resources and care these casualties require must be recognized and triaged as appropriate for the operational and clinical scenario. If the trauma system is resourced appropriately for the demand signal, then these injuries, while devastating are survivable with early hemorrhage control (tourniquets), massive transfusion, and transport to a surgical capability. The role for early (and effective) tourniquets and blood products cannot be overemphasized. Minutes matter for survival for these injuries.

(Refer to JTS Damage Control Resuscitation (DCR) and Whole Blood Transfusion CPGs for further guidance on the resuscitation.5,6)

Occasionally, these patients arrive with CPR in progress. If the mechanism of injury (MOI) is DCBI, the presumption must be made that they have gone into cardiac arrest secondary to hemorrhage, and the casualty needs rapid blood product resuscitation. CPR should be continued while a subclavian or IJ central line for rapid transfusion is placed. U.S. service members with DCBI as the MOI wear body armor, therefore, thoracic injuries were not prominent with this MOI, but another provider should ultrasound the chest to rule out thoracic injury. Outcome data from in military casualties from recent conflicts do suggest a reasonable survival rate in properly selected patients who undergo emergency resuscitative thoracotomy; however, the priority must be resuscitation with blood.7,8 Since these casualties have often exsanguinated, prior to a resuscitative thoracotomy, blood must be started while high quality CPR continues. As the casualty gets resuscitated and the blood pressure returns – all extremity TQs should be assessed and usually need to be tightened or additional TQs added. It is also necessary to ensure the casualty stays warm. Once cardiac activity returns, the casualty should be intubated. As mentioned above, prioritizing intubation over establishing circulation (and filling the heart) will result in cardiac arrest in the exsanguinated DCBI casualty.

#### If they arrive in cardiac arrest:

- Establish large bore IV access or supradiaphragmatic (SCV or IJ) central venous access (8.5Fr cordis)
- Transfuse blood- MTP
- Rule out cardiac/thoracic injury with ultrasound
- Bilateral chest tubes
- Obtain proximal vascular control - resuscitative thoracotomy for aortic occlusion (cross clamp) or REBOA

HEMORRHAGE CONTROL PRIOR TO OPERATIVE INTERVENTION & STABILIZATION

When a DCBI casualty arrives at the Role 2 or Role 3, immediate blood transfusion and hemorrhage control are the priority. All TQs should be assessed for continued hemostasis and may frequently need to be tightened after transfusion starts and the casualty’s blood pressure improves. In some circumstances with high AKAs or bad perineal wounds, the injuries are too proximal for TQ to successfully control the hemorrhage. In these scenarios, there are currently three procedures which can help with hemorrhage control – but they should not delay the casualty getting to the operating room.

1. The first is a junctional TQ. Junctional TQs compress the common femoral vessels. It takes practice to be able to apply effectively. They are non-invasive and some can also act to bind/stabilize a pelvic fracture.
2. The abdominal aortic junctional (AAJT) TQ is a device that likely has some efficacy but has never been well adopted. It was developed for prehospital use, but because it is bulky and causes pain with application, medics have not included it in their aid bags. However, it has efficacy at distal aortic occlusion in animal studies. The AAJT can be applied relatively rapidly, but the casualty will require pain control or intubation. The devices use pressure on the aortic bifurcation to provide proximal control. Ensuring that bleeding is from below the aortic bifurcation is important. There is also a concern that application of this device may cause enteric injury.
3. The last option is Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA). REBOA has emerged as a hemorrhage control adjunct in traumatic shock. The use of REBOA is not widely adopted because the data for Zone 1 occlusion has been mixed.9-11 However, Zone 3 (distal aortic) REBOA would provide inflow control for high AKAs (not amenable to a high and tight TQ) and pelvic/perineal injuries from DCBI. Proper REBOA use requires training and should be done by an experienced provider. If the casualty does not have evidence of intraabdominal injuries (will not require a laparotomy), the use of Zone 3 REBOA just prior to the OR, or in the OR is very effective at proximal hemorrhage control. Like any method of arterial occlusion, REBOA causes distal ischemia and subsequent reperfusion injury; if Zone 3 REBOA is being used, close monitoring of the time of balloon occlusion must be monitored. The longer the distal tissue is ischemic – the higher risk of further tissue damage/necrosis; invasive fungal infection (IFI), and continued myonecrosis. While a safe timeline for Zone 3 occlusion is unknown, the duration of aortic occlusion should be as short as possible. Once the balloon is deflated, distal perfusion must be assessed to avoid secondary ischemic injury to tissue that is already greatly compromised from the primary injury.12 It should be noted that the utility of the REBOA may be significantly limited by the morphology of injury, particularly if affecting the standard femoral access sites.13-15

Refer to JTS Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) for Hemorrhagic Shock CPG for further guidance.12

TRIAGE CONSIDERATIONS

DCBI casualties require massive amounts of blood products and can stress any surgical team given the intensive resources required. Walking Blood Bank initiation is common for casualties with this MOI. These casualties can potentially overwhelm a small Role 2 surgical team, whose goal is further stabilization and movement along the continuum of care. Role 2 surgical teams exist to bridge the gap between point of wounding and higher levels of battlefield care, but faced with one or two DCBI patients simultaneously, these teams will quickly exhaust all their resources. Mass casualty planning and ensuring small teams are augmented with base resources to support the WBB are necessary force multipliers.

Secondary to this MOI, DCBI events usually produce multiple casualties – but because of tactics (space on patrols) only 1-2 are critically injured and the rest, while they likely have injuries requiring surgery, do not require the immediate, resource-intensive interventions that the casualty closest to the blast requires. While this was the scenario most likely seen during U.S. Central Command operations with buried IEDs – further conflicts using artillery or drones could result in the same devastating injury patterns. Triage considerations for LSCO may require a different calculus; however, it is important to 'take care of the patient in front of you’ and maintain situational awareness of the operational environment and constantly track blood and other life-saving resources. REBOA and AAJT may be adjuncts to facilitate hemorrhage control if there are casualties from multiple DCBI events. If more than one patient with this injury pattern is set to arrive to a Role 2 or Role 3 MTF, then it is pragmatic to activate the WBB for (previously) prescreened Low Titer Group O donors.

PREOPERATIVE STUDIES

Useful preoperative studies include chest radiograph, anterior-posterior pelvic radiograph, and a Focused Assessment with Sonography for Trauma exam. Preoperative studies should be utilized to identify source(s) of hemorrhage, but blood transfusion and initial hemorrhage control should be prioritized in an unstable patient.

At the Role 3, if there is substantial concern of a TBI requiring operative intervention, and there is a neurosurgeon available, then an expeditious head CT can be considered on the way to the OR (if the patient is hemodynamically stable). If no axial imaging (CT) was performed preoperatively, total body CT scan (trauma scan) should be considered post op on the way to the ICU (if the patient is hemodynamically stable).