Management of Traumatic Soft Tissue and Vascular Injuries to the Neck




Introduction


Patients with evidence of vascular or soft tissue trauma must be approached in a similar fashion as all trauma patients. Primary and secondary surveys initially screen for any imminently life-threatening injuries and guide the acute workup. Occasionally, that survey reveals a vascular injury to the neck requiring immediate surgical exploration, but in most cases, soft tissue injuries are addressed following initial evaluation and stabilization.


Fractures of the facial skeleton, injury of the orbit, pharyngoesophageal perforation, and laryngotracheal trauma must be considered and incorporated into the comprehensive approach to the trauma patient, but the details of the specific management of these injuries are addressed elsewhere in this textbook. Here we focus on the repair of mucosal and cutaneous injury, as well as the evaluation and management of vascular trauma.




Key Operative Learning Points




  • 1.

    A comprehensive knowledge of head and neck anatomy is essential in order to approach the wide variety of traumatic injuries.


  • 2.

    Soft tissue repair requires meticulous attention to anatomic re-approximation with wound eversion and tension-free closure.


  • 3.

    Management of vascular trauma should follow a systematic approach and appropriate application of diagnostic and therapeutic interventions.


  • 4.

    The management of certain vascular and soft tissue injuries may require experience and techniques beyond the scope of practice of many head and neck surgeons, and consultation with additional specialists may be required.





Preoperative Period


History




  • 1.

    History of present illness



    • a.

      Mechanism of injury: This is the single most important piece of historical information and will guide further history taking, physical examination, and workup.



      • 1)

        Determining the type of trauma allows an estimation of forces involved and potential severity of the injury.



        • a)

          Types of blunt trauma: motor vehicle accident, fall, or assault


        • b)

          Types of penetrating trauma: impalement, stab wound, projectile trauma, or gunshot wounds.The type of firearm and projectile should be investigated when possible to estimate the energy transmitted with the injury. A high-power rifle wound, for instance, will cause a greater degree of injury out of the immediate path of the projectile due to concussion and cavitation. Such injuries can be missed on initial evaluation and can result in delayed soft tissue necrosis.




    • b.

      Timing of the injury: Prolonged delay will increase the risk of infection following primary closure.


    • c.

      Additional historical considerations



      • 1)

        Memory of event/loss of consciousness


      • 2)

        High-volume or pulsatile bleeding prior to presentation


      • 3)

        Restrained or unrestrained, airbag deployment, and the use of a helmet



    • d.

      Symptoms that may suggest additional injuries



      • 1)

        Dyspnea


      • 2)

        Dysphonia


      • 3)

        Nasal obstruction


      • 4)

        Changes in vision


      • 5)

        Malocclusion


      • 6)

        Epistaxis/rhinorrhea




  • 2.

    Past medical history



    • a.

      Medical illness



      • 1)

        Disease states that may affect wound healing or infection risk (e.g., diabetes, immunocompromised states)



    • b.

      Prior surgery and anesthesia


    • c.

      Family history: bleeding disorders


    • d.

      Medications



      • 1)

        Anticoagulants



    • e.

      Allergies



      • 1)

        Antibiotics


      • 2)

        Local anesthetics





Physical Examination




  • 1.

    Primary and secondary trauma surveys


  • 2.

    “Hard signs” of penetrating trauma


  • 3.

    Neurologic examination


  • 4.

    Signs of skull base injury


  • 5.

    Types of soft tissue trauma



    • a.

      Lacerations



      • 1)

        Simple, stellate, flap



    • b.

      Abrasions


    • c.

      Avulsions


    • d.

      Burns


    • e.

      Bite wounds—human/animal


    • f.

      Gunshot and stab wounds



  • 6.

    Specific anatomic evaluations



    • a.

      Facial skeleton, projection, occlusion


    • b.

      Facial nerve function


    • c.

      Globe, pupillary response, orbit, eyelid, and lacrimal apparatus


    • d.

      Lip, oral cavity, and pharynx


    • e.

      Scalp


    • f.

      Nasal deformity, septal hematoma


    • g.

      Ear




Imaging


None


For simple soft tissue trauma with no evidence of more serious injury and low suspicion based on mechanism of injury, no imaging is required.


Computed Tomography


Computed tomography (CT) imaging is the mainstay of the trauma evaluation. In addition to the standard trauma head and cervical spine CT, noncontrast maxillofacial scans should be considered in patients with evidence of significant soft tissue injury (facial edema and ecchymosis) to evaluate for underlying trauma to the facial skeleton or skull base. A CT scan of the neck with contrast may help to evaluate injury to the upper aerodigestive tract. These studies may also identify orbital hematoma and injuries to the globe.


Computed Tomography Angiography


CT angiography (CTA) should be considered when initial studies have demonstrated evidence of skull base fractures extending close to the carotid canal. It has also become the dominant imaging modality in the evaluation of penetrating trauma of the neck.


Magnetic Resonance Imaging


While magnetic resonance imaging (MRI) may have some value in delayed evaluation of traumatic vascular and soft tissue injuries of the head and neck, its role is limited in the acute and preoperative setting.


Angiography


Four-vessel digital subtraction angiography is the generally accepted modality used in the evaluation of suspected vascular injury to the neck. Traditionally, it was a key part of the classical algorithms for management of penetrating trauma based on anatomic zones of injury. While somewhat controversial, its role in that respect has decreased in favor of more selective use. Over time, endovascular techniques have improved, and angiography as a diagnostic study can be combined with a variety of therapeutic interventions, including embolization and stenting, instead of open surgical exploration.


Duplex Ultrasonography


This modality may be used in the evaluation of the carotid arteries, but subtle signs of injury may be missed, and there is a high degree of interoperator variability.


Indications




  • 1.

    Indications for immediate surgical exploration after penetrating trauma; “Hard signs”



    • a.

      Shock


    • b.

      Pulsatile bleeding


    • c.

      Expanding hematoma


    • d.

      Unilateral pulse deficit


    • e.

      Signs of stroke/cerebral ischemia


    • f.

      Bruit or thrill


    • g.

      Stridor, hoarseness


    • h.

      Extensive subcutaneous air or wound bubbling



  • 2.

    Indications for additional evaluation and possible exploration; “Soft signs”



    • a.

      History of heavy or pulsatile bleeding


    • b.

      Presence of clot


    • c.

      Findings on angiography or CTA



  • 3.

    Lacerations: P – capitalize to be consistentrimary closure usually indicated


  • 4.

    Burns: Operative débridement may be required acutely.


  • 5.

    Avulsions and abrasions: initial management usually limited to wound care


  • 6.

    Penetrating trauma: Usually left open but partial closure of large wounds may be considered.



Contraindications




  • 1.

    Other immediately life-threatening injury


  • 2.

    Hemodynamic instability


  • 3.

    Contaminated wounds open greater than 24 hours and penetrating wounds



  • Relative contraindication: Primary closure can be considered, but infection risk is increased. Antibiotics and drains may be appropriate.



Preoperative Preparation




  • 1.

    Airway: Evaluate and secure when appropriate.


  • 2.

    Control of hemorrhage: Active bleeding should be controlled in the trauma bay or emergency department.



    • a.

      For suspected injury to the carotid artery, an assistant may need to maintain manual pressure to prevent exsanguination while proceeding emergently to the operating room. A balance must be struck between adequate pressure to control hemorrhage and the need to maintain cerebral perfusion.


    • b.

      Hemorrhage from other soft tissue trauma should be controlled with pressure and dressings. Nasal packing can be used judiciously but with caution if there is concern for skull base injury. If the airway has been controlled, oral and pharyngeal bleeding can generally be controlled with packing. Scalp wounds can result in clinically significant blood loss. Hemostasis can be achieved with pressure dressing or temporary closure with staples or suture until definitive repair is performed.



  • 3.

    Trauma resuscitation


  • 4.

    Laboratory evaluation



    • a.

      Hemoglobin/hematocrit


    • b.

      Type and screen


    • c.

      Toxicology






Operative Period


Anesthesia


General Anesthesia


Emergent exploration of the neck requires a definitive airway and general anesthesia. Transnasal intubation might improve access to the high carotid by allowing increased subluxation and anterior displacement of the mandible. Transnasal intubation should not be performed if there is suspicion for skull base injury.


General anesthesia is also preferable for extensive soft tissue injuries, which will require extensive débridement and a lengthy repair. Long-acting paralytics should be avoided if nerve dissection and stimulation are required, as in facial nerve exploration and repair.


Sedation


Intravenous sedation may be an option if general anesthesia is contraindicated or if inadequate resources are available in a timely manner, since it can be administered outside of the operating room and without an anesthesiologist. The patient, however, must be continuously monitored, and a separate physician should be dedicated to that role. Sedation is often a good option in the pediatric population when general anesthesia is not required, but cooperation is inadequate to permit local anesthesia alone.


Local Anesthesia


The majority of minor soft tissue trauma can be repaired using local anesthesia alone. Knowledge of sensory neuroanatomy and regional blocks can be extremely useful. These techniques allow excellent anesthesia with a lower total dose of anesthetic, and they avoid further distortion of the anatomy by local infiltration. Even if some local infiltration is needed or desired for hemostasis, blocking the area first will significantly improve patient comfort. Some of the simplest and most useful blocks include the inferior alveolar, mental, infraorbital, supraorbital, and supratrochlear.


Positioning


Positioning will vary depending on the specific procedure performed. For exploration of the neck, the patient is positioned supine with some degree of extension of the head and neck. The patient’s arms should be secured at the sides so that access to the chest is maintained. The chest should also be prepared and included in the surgical field in the event that vascular access requires removal of the clavicle or a median sternotomy. Turning the bed 90 or 180 degrees may be helpful.


For soft tissue repairs, the patient should be positioned and prepped to afford access to all injuries including the scalp. For facial wounds, both sides of the face should remain in the field to evaluate symmetry. In awake and sedated procedures, semirecumbent positioning will improve the patient’s comfort and help him or her to maintain his or her airway.


Perioperative Antibiotic Prophylaxis


Operative primary closure of open wounds of the head and neck could be considered clean-contaminated or infected surgery, and, therefore, prophylactic antibiotic therapy would be indicated, according to clinical practice guidelines for surgery. The use of antibiotics for simple wound repair, however, has been investigated with multiple clinical trials and a definite benefit has not been demonstrated.


Prophylactic antibiotics are, therefore, reserved for extensive injury or contamination and bite wounds, where a benefit has been demonstrated.




  • First line: cefazolin + metronidazole, cefuroxime + metronidazole, or ampicillin-sulbactam



  • Second line: clindamycin



For bite wounds:


Prophylactic antibiotics for 3 to 5 days are indicated for repaired human or animal bite wounds to the head and face.




  • First-line treatment: amoxicillin-clavulanate



  • Second line:




    • Moxifloxacin



    • Doxycycline



    • Cefuroxime + clindamycin or metronidazole



    • Trimethoprim-sulfamethoxazole + metronidazole or clindamycin




Tetanus toxoid should also be administered if not previously received within 10 years or if unknown.


Monitoring





  • Routine general or sedation anesthesia monitoring.



  • EMG: Multichannel electromyography is essential in patients undergoing facial nerve exploration and repair.



  • EMG/EEG: Electromyography and electroencephalography can be used to evaluate for cerebral ischemia during routine carotid surgery but are not typically available in emergency surgery.



Pressure transduction: Backflow pressure of the distal carotid stump after clamping can be used to assess cerebral perfusion. Pressures below 50 mmHg indicate inadequate collateral flow and necessitate shunting.


Instruments and Equipment to Have Available


Available equipment should be appropriate for the intended procedure and any contingency. This may include:



  • 1.

    Basic plastic and eyelid instruments, hooks, and retractors


  • 2.

    Intraoral retractors (Obwegeser, Minnesota, Weider [sweetheart])


  • 3.

    Monopolar and fine bipolar cautery


  • 4.

    EMG/nerve stimulation and monitoring system


  • 5.

    Microsurgical instrumentation for nerve repair or revascularization


  • 6.

    Vascular instruments and clamps


  • 7.

    Specialty vascular supplies (shunts, balloon catheters)



Prerequisite Skills




  • 1.

    Soft tissue handling and basic reconstructive technique


  • 2.

    Oculoplastic experience in the management of major eyelid and lacrimal apparatus injuries


  • 3.

    Microsurgical skill for neurorrhaphy and revascularization of amputated tissue segments


  • 4.

    Neck dissection skills and management of the great vessels of the neck


  • 5.

    Vascular techniques for carotid repair and revascularization



Operative Risks




  • 1.

    Orbital injury


  • 2.

    Facial nerve injury


  • 3.

    Salivary duct obstruction


  • 4.

    Lacrimal/canalicular obstruction


  • 5.

    Skin ischemia


  • 6.

    Massive hemorrhage/death


  • 7.

    Stroke



Surgical Techniques


Wound Preparation





  • Irrigation




    • Open wounds should be copiously irrigated with saline. For large and heavily soiled wounds, pulsatile irrigation systems can help to efficiently cleanse the wound. Dried blood, clots, and foreign material should be removed, and the wounds should be carefully inspected to fully appreciate all injuries. When included in the field, the eye should be protected with a scleral shield or tarsorrhaphy.




  • Débridement




    • Foreign material that is not rinsed from the wound should be removed mechanically. Most large pieces of debris can be removed with agitation with a sponge or forceps. Implanted projectiles and glass may need to be gently dissected from the wounds. Small imbedded foreign bodies that are retained will result in tattooing so attempts should be made to remove them with mechanical débridement or dermabrasion. This can be done carefully with a scalpel in a scraping rather than cutting motion.



    • Devitalized tissue should be sharply excised. Severely contused wound edges can be débrided to facilitate closure between healthier tissues. Rough and irregular wound edges can also be débrided to facilitate simple linear or curvilinear re-approximation.




Re-approximation and Adjacent Tissue Rearrangement



Apr 3, 2019 | Posted by in OTOLARYNGOLOGY | Comments Off on Management of Traumatic Soft Tissue and Vascular Injuries to the Neck
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