OPERATIVE APPROACH

PRIORITIZATION AND SURGICAL TEAMS

DCBI patients undergo dozens of operations over their course of care. The goal of the first operation is simple but not easy: hemorrhage control and debride dead tissue while removing contamination (from the soil and device fragmentation). There must be coordination and communication between the anesthesia and surgical teams throughout the entire case. The OR should be warmed to as hot as it can get, since these casualties are always hypothermic, even if the ambient temperature is 100° Fahrenheit. Blood loss is ongoing throughout these cases and the anesthesia provider must keep up with transfusion requirements. Vasopressors should be avoided until it is clear the patient is euvolemic. There should be a low threshold to activate a WBB for warm fresh whole blood even if the blood bank has ample supply of stored blood.

Intraoperative management of DCBI patients requires a team approach, best achieved with general/trauma surgeons and orthopedic surgeons working concurrently when possible. For example, the general/trauma surgeon can achieve proximal vascular control if necessary and address any truncal injuries, if present, while the orthopedic surgeon deals with obtaining hemostasis in the wound, stabilizing the pelvis when indicated, and debriding dead and devitalized soft tissue. If the wounds are only in the extremities, two surgeons working together on each extremity is more efficient. Keeping OR times as short as possible, while achieving hemorrhage and contamination control, should be the goal. If there is a third team, they can address the upper extremity injuries. This approach maximizes efficiency and limits prolonged physiological insult to a severely injured patient. Without evidence of intraabdominal or visceral injury, colonic diversion should not be done during the first operation. Additionally, the wounds should not be placed in vacuum assisted closure (VAC) dressings on the initial operation since 1) they will be returning to the OR in <24 hours; 2) in patients who are coagulopathic and have a capillary leak – the negative pressure dressings can result in more bleeding and can create a detrimental cycle of blood loss and increase transfusion requirements. When VACs are placed on the patients, the blood loss might get underrecognized in a busy ICU, post-operatively. During the first operation: be expeditious and efficient, keep the casualty warm, get hemorrhage control in the wounds, debride dirt, particulate matter and tissue that is clearly dead or devitalized.

Dress the wounds with wet to dry or Dakin’s dressings. Using mesh gauze and staplers, dressings can be fashioned to fit these challenging wounds. If the casualty has an open pelvic fracture and the perineum and abdomen are connected or there is evisceration through the perineal injury, then laparotomy is needed to assess for and repair abdominal injuries. This approach, while successful, should be a planning factor when considering triage.

PROXIMAL VASCULAR CONTROL

The level of proximal vascular control required to control bleeding is dictated by several factors: associated pelvic disruption, level of tourniquet placement and level of traumatic amputation(s). Typically, vascular control should be achieved at the most distal level possible, including control via a retroperitoneal approach or in the groin. If a laparotomy is performed, walking the clamps down the internal and external iliac arteries in patients with massive pelvic injuries is another excellent technique to control hemorrhage. This technique can be augmented by Zone 3 REBOA with distal aortic occlusion while vascular control is being obtained in the pelvis or groin.19 In cases of pelvic floor injuries with open pelvic wounds and active external posterior bleeding, temporary control of the internal iliac arteries is crucial as these wounds have a very high lethality.20 This iliac vascular control can be achieved with clamps, vessel loops or Rommel tourniquets based on facility resources. Achieving hemorrhage control must be prioritized, but the risk of ischemic tissue at the site of injury and subsequent infection, overwhelming infection, and diminished wound healing must be recognized.

Proximal control, particularly when involving ligation of iliac vessels, should not be done as it is associated with significant pelvic girdle, perineum, and thigh necrosis, as well as angioinvasive fungal infections, potentially leading to hip disarticulation or trans-pelvic amputation, hemicorpectomy and death.21 An attempt to re-perfuse the internal iliac arteries should be made at the index or subsequent procedure. Ligation of both internal iliac arteries must be avoided if at all possible. However, in cases of ongoing pelvic hemorrhage despite pelvic packing and angiographic embolization, bilateral internal iliac artery temporary occlusion may be necessary. These casualties must return to the OR, because significant tissue necrosis should be anticipated. In the case of prolonged warm ischemia time, prophylactic fasciotomies of the residual limb are often necessary as compartment syndrome occurs frequently, even in the presence of large open wounds.

Refer to JTS Acute Extremity Compartment Syndrome and the Role of Fasciotomy in Extremity War Wounds CPG for further guidance.22

ROLE OF PROXIMAL DIVERSION

So much experience has been gained with creative use of wound care and VAC dressings (using stoma paste, staplers, Ioban, Lonestar retractor elastics, etc.) as well as fecal management systems, that colostomy can usually be avoided. Colostomy is indicated in DCBI patients with diagnosed rectal injury or massive pelvic disruption/open pelvic fracture with extremely high suspicion for anorectal injuries. There is rarely a need to do a colostomy on the initial operative intervention.

ORTHOPAEDIC CONSIDERATIONS

It is common for DCBI patients to present with traumatic bilateral lower extremity amputations at various levels from transtibial to very high transfemoral levels. These are often associated with extremely complex soft tissue blast wounds that include the perineal and gluteal region (see Figure 1). In addition to lower extremity amputations, these injury patterns are often associated with complex pelvis and acetabular injuries (see Figure 2). Traumatic amputation of the non-dominant upper extremity can also be seen in these complex patterns due to weapons holding stance.

Optimal orthopedic care entails:

1. Ensuring extremity hemorrhage control
2. Pelvic external fixation if there is hemorrhage from a pelvic fracture, especially with sacroiliac disruption
3. Stabilization of extremity fractures in salvageable limbs / limb remnants
4. Debridement of devitalized tissue

Once in the operating room, hemorrhage control in the wound can be accomplished by replacing field TQ with pneumatic TQ. Total TQ time should be recorded, and it is imperative to communicate with anesthesia when the TQs are being released. These patients can have profound hypotension when the TQs are released and anesthesia must be ready with blood, calcium, bicarb and be prepared to hyperventilate the patient to manage the large acid load from reperfusion of the ischemic limb as inflow is restored. It is important to note that examination of the pelvic ring should be performed to address stability. Pelvic fractures can be stabilized with the use of clamped sheets or commercial pelvic binders centered over the greater trochanters, or a pelvic external fixator if resources and ability allow for this.

Figure 1. Dismounted Complex Blast Injuries
Figure 2. Open Pelvic Ring Injury

Index operative procedures should be prioritized with the surgical team leader; these surgeries require a team approach with constant communication.20 Hemorrhage control of traumatic amputations and peri-pelvic sources is the main priority along with restoration of blood volume and keeping the patient warm. Pelvic and perineal packing with hemostatic dressings such as Combat Gauze may be helpful for small-vessel hemorrhage control and cases with continued oozing due to coagulopathy.

Revision or completion amputations should occur at the most distal viable level with suture ligation or double ligation of all named vessels in an open, length-preserving fashion. Limb length is inversely proportional to later energy expenditure (i.e. life expectancy) so preserving as much bony length as possible is preferable. Any viable skin and soft tissue should be preserved; guillotine-style or open circular amputations are contraindicated. Care should be given to salvaging healthy tissue for flap coverage, even if it is an atypical rotational flap in the face of destroyed or missing conventional flap tissue. If the pelvic ring is unstable, a pelvic external fixator should be used instead of a binder, to facilitate access to the groins, debridement of proximal wounds and other procedures. Pin placement in the iliac crest or anterior inferior iliac spine are both appropriate, with the latter offering greater reduction control but requiring fluoroscopy and surgeon experience. If the patient requires a colostomy and/or suprapubic (SP) catheter, these procedures must be coordinated with orthopedic surgery to determine optimal placement, so they do not interfere with future pelvic approaches necessary for fixation. External fixation of long bone fractures should be accomplished as soon as possible depending upon the acuity of the patient. Smaller bone and joint fractures can be addressed if the patient remains stable, otherwise they are deferred until after the initial operative resuscitation.

Refer to JTS Amputation: Evaluation and Treatment CPG for further guidance. 21

SOFT TISSUE DEBRIDEMENT

An appropriate balance of adequate surgical debridement and restoration of physiology is critically important during the initial surgical procedure for DCBI patients. DCBI MOI results in wounds that are complex and extensive. They are grossly contaminated with dirt, fragment debris, clothing, and foliage. Wounds should be incised with well-planned incisions extending longitudinally from the primary zone of injury to healthy tissue with consideration of future reconstructive or closure options.22 Systematic irrigation and debridement of nonviable skin, subcutaneous tissue, fascia, muscle, periosteum, and bone is critical to reduce the bioburden and later risk of sepsis.22 Blast wounds tend to evolve and repeat surgical irrigation/debridement should be performed at least every 24 hours until the wound stabilizes and there is no further evidence of contamination, or ongoing myonecrosis. If tissue is questionable and not contaminated, it should be maintained and addressed at the subsequent surgical debridement the following day. However, since the timing of the next operation (often at the next role of care) is unpredictable, avoid leaving marginally viable tissue behind while in theater, as many of these complex wounds will develop progressive necrosis. When present, pelvic/perineal and pelvic wounds need to be similarly addressed.23

Refer to JTS War Wounds: Wound Debridement and Irrigation CPG for further guidance.19

ADDITIONAL VASCULAR CONSIDERATIONS

If the DCBI is associated with a venous injury: iliac or common femoral; these injuries should be shunted or repaired rather than ligated, to preserve venous outflow. Unless easily repairable, arterial injuries in these critically injured patients should be managed initially with shunting followed by formal repair at subsequent operation within 12 -24 hours depending upon patient stability.24 During the index operation, restoring inflow is critical and restoring outflow is optimal. Even if the venous shunt goes down, or the vein clots after repair, the initial restoration of outflow is beneficial for the remaining tissue. If there are viable limbs and muscle contained by fascial compartments, fasciotomies are necessary as compartment syndrome can occur even in the presence of large open wounds if the fascia remains intact.

Refer to JTS Vascular Injury and Acute Extremity Compartment Syndrome and the Role of Fasciotomy in Extremity War Wounds CPGs for further guidance.24,19

ASSOCIATED GENITOURINARY (GU) INJURIES

DCBI is associated with perineal wounds and injuries to genitalia. Bladder and ureter injuries are less common, but if a large perineal wound is present, appropriate studies should be undertaken to assess for potential injury to these GU organs. Perineal, genital, and urethral wounds should be addressed with urinary management and basic wound care. Since the initial focus on the index operation is hemorrhage control, debridement and irrigation of wounds, definitive management of GU wounds should be staged. If scrotal skin is missing, the testicles should be wrapped in Adaptec or Vaseline gauze to prevent the tunica from desiccating. In the case of a penile or urethral injury, a foley catheter should be attempted and tissue temporarily closed over the urethra. A penile or distal urethral injury is not a reason for an SP tube if a urinary catheter can be placed. Adjuncts to help place a catheter include ureteroscope, wires, and fluoroscopy, but should be performed at an interval operation once the casualty is stabilized. A retrograde urethrogram should be performed if a urethral injury is suspected. In the case of urethral disruption and inability to place a catheter over a wire, a suprapubic catheter (tube) should be placed either percutaneously or open. If available, seek the consult or assistance of a urologist.

Refer to JTS Genitourinary Injury Trauma Management CPG for further guidance.23

ASSOCIATED (OCCULT) RECTAL INJURIES

DCBI casualties with perineal wounds or many fragments to the perineum, buttocks or groin should undergo a proctoscopy prior to leaving the operating room. Most of these casualties do not have the opportunity to undergo full CT scan prior to going to the OR and CT does not reliably exclude rectal injury. Therefore, fragmentation wounds to the perineum and perianal regions should generally prompt examination of the rectum (proctoscopy or flexible sigmoidoscopy) even if digital rectal examination in the emergency room is negative for blood. This may be difficult in the supine position and may be readily completed in the supported lateral position. Completion of the anorectal exam should be done prior to completing laparotomy to aid decision making with respect to colonic diversion. If clot, active bleeding, or injury is identified on anorectal examination, the distal sigmoid colon/proximal rectum should be divided and later matured at a subsequent operation into an end colostomy once the patient is stabilized further along the evacuation chain. Distal rectal wash out is not necessary unless there is bulky retained stool in the presence of a suspected penetrating injury.

CONSIDERATION OF LATERAL OR PRONE POSITIONING

In most patients, the posterior soft tissue injuries can be addressed with elevation of the amputated stumps or with the patient in a lateral position after the supine portion of the case has been completed. However, certain injury patterns have a large posterior element. In these cases, prone or lateral positioning is sometimes necessary, after hemorrhage control, to adequately debride wounds in the gluteal and low back region. This decision should not be made lightly, due to the time requirements and risks involved. This can often be deferred to secondary procedures. Lateral positioning is preferred as it allows for easier airway control, but the latter may be needed for complex bilateral lower extremity and truncal wounds. A Jackson table can facilitate a safe transition to the prone position. Unstable pelvic ring injuries should be stabilized prior to prone positioning, as this position can exacerbate hemorrhage.

WOUND DRESSINGS

Traumatic wounds should not be definitively closed until multiple adequate debridement and irrigation procedures have been performed. A series of surgical debridement and high-volume irrigation (9L/limb) is necessary to prepare wounds for closure or coverage. Wound closure and tissue coverage can take weeks. Serial wound stability without evidence of infection or continued myonecrosis is required. The wound should not be closed the first day it looks healthy. Serial intraoperative wound inspections are necessary. The risk of early wound closure is an infection that will require more debridement and possible loss of limb length. The extensive soft tissue destruction and degree of contamination in DCBI wounds make them infected until proven otherwise. Once there is no evidence of myonecrosis, tension can be placed on healthy skin and soft tissue to prevent loss of tissue domain and skin retraction. The preferred initial wound dressings are wet-to-dry gauze with Dakin’s (combat gauze can be used at initial operation as a hemostatic adjunct). After the risk of bleeding has subsided, negative pressure wound therapy can be used and is very useful for fixed wing evacuation.

INVASIVE FUNGAL INFECTIONS (IFI)

Invasive fungal infections were first described in DCBI casualties from Afghanistan during combat operations from 2009 - 2011.25 IFI is associated with continued wound progression and myonecrosis. Patients are at risk for invasive fungal infection if three of the following factors are present:

- Dismounted blast injury
- Above knee immediate amputation
- Extensive perineal/genitourinary/rectal injury
- Ultra massive transfusion of >20 units in the first 24 hours

For these patients, it is recommended that the irrigation solution be switched to high-volume Dakin’s solution. The IFI and blast protocol should be followed. Daily OR trips for wound inspection must occur until there is no further evidence of fungal infection.22

Refer to JTS Invasive Fungal Infection in War Wounds CPG for further guidance.18