Facial Trauma: Soft Tissue Lacerations and Burns

History

Every clinical encounter begins with an accurate and thorough history followed by a detailed physical examination. The approach to patients with facial trauma is no different. However, because these patients often have a wide range of concomitant injuries, access to the patient for a history and physical examination may be limited on initial presentation. Multiply injured patients require systematic evaluation according to Advanced Trauma Life Support (ATLS) protocol. Patients with severe or life-threatening injuries to the chest, abdomen, or extremities present a unique challenge. A cursory head and neck examination by first responders and even other physicians may reveal seemingly uncomplicated facial injuries, which, when evaluated carefully, demonstrate significant structural or functional compromise, such as a facial nerve or parotid duct injury, lid laceration with exposed cornea, retained foreign bodies, or canalicular injury. Every possible attempt to gain an accurate history and perform a complete examination should be made before opportunities for optimal repair are missed.

An often neglected component of the history is premorbid appearance and function. It should not be taken for granted that a patient with facial weakness on examination had normal facial nerve function before the injury. Details like this must be obtained to prevent unnecessary work-up and treatment. If possible, it is helpful to have a photo of the patient from friends or family when significant disfigurement occurs. Even a driver's license photograph may be helpful. Although a photograph may not change overall management, it does provide a frame of reference for patient and family expectations of repair and gives the surgeon an opportunity to better see the patient as a person rather than as another injured face.

The social context in which injuries take place is as important as the physical context. Injuries from interpersonal violence make up a large component of facial trauma. Assault and abuse victims may not volunteer the mechanism or the assailant without confidence that the health care system will protect them from immediate and future harm. Depending on their age and development, children may not be able to volunteer details of abuse and require a thorough history from parents or caregivers and witnesses in an effort to identify discrepancies. More than 50% of victims of child abuse demonstrate injuries to the face, although injuries to the face alone are not sufficient to suspect abuse. Abuse should be suspected when the described mechanism does not fit the injury pattern, or when the child displays signs of abuse elsewhere. In the United States, any “reasonable suspicion” of child abuse legally mandates reporting to the appropriate authority.

A detailed history of the mechanism is crucial. The traumatic event should be reconstructed as accurately as possible, including time, location, involved parties, and degree of contamination (e.g., dog bite or clean laceration from a sharp object). In motor vehicle injuries, pertinent components include speed of impact; the victim's use of a seatbelt or helmet; deployment of airbags; whether the victim was ejected from the vehicle; the presence of broken glass, chemicals, or fire at the scene; and involvement of drugs or alcohol. In injuries that result from trips or falls, it is important to ascertain the height of the drop, the nature of the landing area, and whether the patient struck any objects. The level of consciousness during and after the injury should always be determined. In cases of assault, the type of weapon, information about the assailant, and any prior history of assault should be determined. Careful documentation is critical in these instances, both for treatment and for medicolegal reasons.

Ensuring tetanus prophylaxis is imperative. Tetanus-prone wounds are typically deep lacerations, avulsions, or puncture wounds contaminated with soil, feces, saliva, or mineral debris. If the immunization status is unknown, or if the patient has not completed the series of tetanus immunizations, tetanus immunoglobulin and vaccine (tetanus toxoid) should be administered. All other patients who have completed a primary immunization series should receive toxoid unless they have had a booster or completed the series within the past 5 years.

Physical Examination

Many soft tissue injuries to the face occur in the setting of underlying trauma to the maxillofacial skeleton, and a thorough examination must be performed with this in mind. Although the focus of this chapter is on injury to the soft tissues, an adequate evaluation of facial trauma includes an assessment to rule out fractures. A systematic approach is essential to prevent errors, both in diagnosis and management. Every practitioner who cares for a trauma patient is obligated to follow ATLS protocol regardless of that caregiver's role in treatment. An orderly approach using the ABCDE mnemonic ( a irway, b reathing, c irculation, d isability, e xposure) with primary and secondary surveys ensures that the most threatening conditions are dealt with first and that nothing is missed. Missed facial injuries are rare with thorough examination but can have significant ramifications. A seemingly innocuous forehead laceration in the emergency department triaged quickly to the “facial trauma service” may mask occult intracranial or cervical spine injury, depending on the mechanism—something that could be missed by simply focusing on fixing the laceration rather than treating the patient. Vigilance must be exercised in patients transferred from other institutions, and experienced surgeons recognize that an assessment from a transferring provider may not be an adequate substitute for their own careful examination.

The examination begins with careful investigation of problems with the airway, breathing, and circulation—the ABCs—immediate or impending. Airway compromise is rarely associated with superficial soft tissue trauma alone; however, severe hemorrhage with collection of blood in the upper airway can rapidly compromise the ABCs, particularly in a combative or obtunded patient. The airway is secured by controlling hemorrhage with direct pressure or identification and ligation of the injured vessel. However, this must be performed with caution to avoid injuring other important structures, such as the facial nerve or parotid duct, in attempts to quickly stop hemorrhage by clamping a bleeding vessel in the wound bed. Another injury that requires immediate intervention is that of corneal exposure from eyelid laceration or avulsion. Immediate corneal protection prevents potentially devastating ocular injury ( Fig. 19.1 ).

A general assessment of surface anatomy includes assessing the scalp and facial features in repose to evaluate for asymmetries that suggest underlying skeletal or neurologic injury. The remainder of the examination is conducted systematically. The exact order of the examination is unimportant, but the same sequence should be used every time to ensure a comprehensive assessment of injuries. Commonly used algorithms include top-down examinations with systematic progression from head and scalp to ears, face, eyes, nose, mouth, neck, and throat. Facial bones are palpated for deformities, step-offs, and mobility; this includes the entire skull, orbit, zygoma, maxilla, palate, and mandible. Computed tomography (CT) scans and plain films are not an adequate substitute for this examination. Although most traumatic soft tissue injuries to the face are often obvious on initial inspection, certain areas require careful examination to rule out more significant injuries. Otoscopy often demonstrates a blood-filled canal in patients with facial lacerations who are transported supine. After removal of blood and debris, closer inspection may reveal lacerations in the ear canal in the setting of a skull base fracture even in the absence of hemotympanum. A thorough examination of the eyes and periorbital areas includes the medial canthus, fornix, conjunctiva, cornea, and orbital rims. A careful examination of these areas is even more crucial in an obtunded patient who cannot volunteer symptoms of visual loss, ocular or conjunctival foreign body, or diplopia. When lacerations of the upper or lower eyelids are present in the medial canthal region or telecanthus, the caregiver must rule out disruption of the lacrimal apparatus or nasoorbitoethmoid fracture. The long-term sequela of canalicular disruption with subsequent blockage of a tear drainage pathway into the nose is epiphora, and it is not present on initial examination. A positive fluorescein instillation test (Jones test) effectively rules out drainage pathway disruption, although probing the lacrimal punctum and ducts with lacrimal probes while examining the wound before repair is safe, reliable, and relatively straightforward. Every patient should have visual fields tested, and motility and acuity should be assessed and documented. Patients with periorbital or ocular trauma should also be evaluated by an ophthalmologist for a full examination, including a dilated retinal examination.

All examination findings, both positive and negative, should be documented, including the time at which the findings were noted. Simple omissions in the medical record can lead to significant difficulties in ongoing diagnosis and management, in addition to unnecessary medicolegal liability.

Anesthesia

Complete assessment of wounds is often only possible after establishing adequate anesthesia. Additional patient discomfort during wound exploration and repair is unnecessary and creates an adverse environment for a technically successful repair. Comfortable working conditions for both the patient and the physician can generally be established with local anesthetics through topical application, infiltration, or nerve blocks of the trigeminal distribution. Lidocaine with or without epinephrine in concentrations from 0.5% to 2% is a commonly used agent for infiltration or regional block. Lidocaine is well tolerated by nearly all patients with minimal side effects and a safe dosing range. Widely quoted maximum doses for local anesthetics actually have little basis in human studies or evidence-based medicine and are largely extrapolated from animal data and case reports of toxicity. These theoretic guidelines suggest that toxicity from lidocaine, in the form of central nervous system disturbances (e.g., seizures or cardiac dysrhythmias), will develop with doses greater than 4.5 mg/kg of patient body weight or 7 mg/kg if epinephrine is added. However, toxicity is probably multifactorial, taking into account fluid status, age, site of injection, medical comorbidities, and other injuries. Even so, in the multiply injured patient who requires repair at separate sites by more than one practitioner, the aggregate dose of local anesthetic should be tracked and documented by all parties involved to avoid toxicity. In children, doses may be inadvertently high because of the patient's smaller body mass.

Lidocaine alone has a modest vasodilatory effect on capillaries and can impair hemostasis during closure. The addition of epinephrine in dilutions from 1 : 100,000 to 200,000 encourages hemostasis and systemic absorption but requires caution in certain circumstances. Dense infiltration of macerated wound edges or long, tenuous flaps of avulsed skin with epinephrine may compromise otherwise salvageable tissue and should be avoided. The need for local infiltration can be markedly reduced or obviated by a well-performed regional block; physicians involved in the treatment of soft tissue trauma should become facile with their use. Near-total anesthesia of the face for soft tissue work can be accomplished by selective blocks of the infraorbital, supraorbital/supratrochlear, zygomaticotemporal, zygomaticofacial, dorsal nasal, great auricular, and mental nerves. Appropriate use of these blocks decreases both the overall dose of local anesthetic required and the pain associated with the injection of local agents. Blocks are also helpful when infiltration of wound edges would distort important landmarks, such as the vermillion border. Significantly, in a cooperative patient, establishment of good regional anesthesia may eliminate the need to perform a repair under general anesthesia in the operating room. Longer-acting local agents such as bupivacaine may also be used for direct injection into the wound edge or, more appropriately, for a long-acting block in select cases. Bupivacaine does have a narrower therapeutic window than lidocaine with a potential for cardiotoxicity. Ropivacaine is another well-established long-acting local agent with a better dose-dependent toxicity profile than bupivacaine; however, higher cost may be a barrier to its use at many institutions.

The four chief causes of pain associated with injection are due to (1) the temperature of the injectate, (2) the acidity of the solution, (3) the speed of injection, and (4) the size of the needle. These factors are all easily addressed to minimize the discomfort of the patient. Warming the local agent to body temperature decreases the pain of injection. Similarly, buffering 1% lidocaine with 8.4% sodium bicarbonate solution in a ratio of 9 : 1 brings the pH of the solution up from 4 to a value around neutral. The only significant negative trade-off with buffering is the resultant diminished duration of effect, which can be as short as 30 minutes. Injecting slowly with small needles, 27 or preferably 30 gauge, also decreases pain. It is much easier to inject with a small needle when a small syringe is also used, because the discrepancy is smaller between the diameter of the syringe and the diameter of the needle.

A calm, comforting demeanor combined with appropriate technique enables the surgeon to provide the patient with adequate anesthesia without any additional pain or anxiety. With children, it is best to take a graduated approach. Frequently, by the time the consultant is seeing the patient, the initial psychologic trauma has abated, and the child is fairly calm. The treating physician could first talk to the child about something other than the injury. In addition, the clinician should explain everything he or she is going to do in advance. The patient's anxiety only increases when awaiting a “surprise attack.” Next, the clinician should examine some part of the patient's body that was not injured. This nonpainful touching can set the precedent that not everything is going to hurt. Next, the wound is gently examined. Gentle irrigation with warm saline is rarely painful and allows the wound to be cleaned and thoroughly examined. At this point, careful infiltration of local anesthesia with a small-bore needle is almost always possible. Many patients fall asleep during the wound closure. However, for some pediatric patients, the idea of the needle trumps all efforts to alleviate anxiety. Rather than restraining a child to anesthetize a wound through injection, the clinician should choose topical anesthesia or conscious sedation.

Topical anesthesia first gained popularity in the form of a solution of 0.5% tetracaine, 1 : 2000 adrenaline, and 11.8% cocaine, known as TAC anesthesia, after comparable efficacy and safety were demonstrated relative to injection with lidocaine. Based on the potential systemic toxicity and security concerns of the cocaine component of TAC, a variation on this technique, known as LAT (4% lidocaine, 1 : 2000 adrenaline, and 1% tetracaine), has been shown to be equally effective. It is also one-tenth the cost of TAC—a significant savings. Even though LAT and TAC have become agents of choice for anesthetizing simple lacerations in children and select adults, their role in more complex wounds has yet to be defined. In an uncomplicated laceration, it is relatively easy to uniformly administer a topical agent to all areas of the wound bed. Typically, an anesthetic solution is applied by saturated cotton tips or sponges, and it is replaced every few minutes until anesthesia is obtained; this usually takes approximately 10 minutes. However, large, irregular wounds filled with clot or debris that would impair administration and require débridement are not candidates for this method. TAC should also be avoided near mucous membranes because of reports of systemic toxicity associated with high mucosal uptake of cocaine. It is important that adult patients understand that there is a possibility of testing positive for cocaine after TAC administration.

Some children require sedation in addition to adequate local anesthesia. Conscious sedation or procedural sedation of children is a safe and effective way to diminish the potentially significant psychologic distress associated with repair of soft tissue injuries. Administering sedation to children requires training, experience, skill, and appropriate institutional resources. In the emergency setting, this is best administered by trained nursing staff under the direction of a physician or other provider certified to perform procedural sedation in children. This allows the surgeon to focus on the patient's injuries without the added responsibility of drug administration and monitoring. Despite its benefits, sedation does add to emergency department length of stay and cost of treatment; this warrants judicious use when the child may tolerate repair with local anesthetic alone. However, this should not be used as an excuse for withholding sedation for seemingly uncomplicated lacerations in children who are clearly distressed by the prospect of local anesthesia. Several agents have been demonstrated to be effective, including midazolam, ketamine, and fentanyl; these are often used in combination. The most common adverse effects are hypoxia and vomiting, which are usually minor and self-limited or resolve with minimal intervention. Access to suction, supplemental oxygen, and equipment for management of the airway should be in place if sedation is to be used.

Cleaning

Carefully irrigating and cleaning wounds and surrounding skin are important not only for decreasing risk of infection but also to improve visualization of wound characteristics in preparation for repair. In the multiply injured, obtunded, or sedated patient, meticulous cleaning is even more important. It is not an uncommon scenario to encounter an unconscious patient in the trauma bay, positioned supine with an endotracheal tube and bite-block in the mouth, a nasogastric tube taped in place, and a cervical collar around the neck with dry, crusted blood, dirt, or debris concealing soft tissue injuries. With so many impediments to a thorough examination, cleaning the entire head and neck is critical to avoid missing injuries. This includes hair-bearing scalp and facial hair, where many soft tissue injuries are easily hidden. Hair may need to be shaved or trimmed to adequately clean, assess, and repair injuries. Eyebrows may be trimmed conservatively or shaved if necessary, although it may take 6 months for them to fully regrow.

In most cases, simple antimicrobial cleansers such as chlorhexidine are adequate. Saline alone does little to remove bloody crusts; warm saline is slightly better. Warm saline with dilute peroxide is better still, although studies that show fibroblast and keratinocyte inhibition in vitro with peroxide and povidone-iodine have led to many authors voicing caution regarding their liberal use in open wounds. For most wounds, warm saline under moderate pressure will be adequate for irrigating debris and foreign material. Retained foreign bodies left unrecognized can develop into a significant problem and are a well-known cause of medicolegal action related to repair of traumatic injuries. Fortunately, the limited depth of soft tissue in the face relative to other areas of the body allows for most foreign material to be identified in the course of routine wound exploration.

Imaging is helpful in certain circumstances. Glass is a common foreign body associated with motor vehicle trauma and is easily detected with plain films. However, the utility of these studies is limited to wounds deeper than the immediate subcutaneous fat. Contrary to commonly held assumptions, a negative CT scan result does not rule out a retained foreign body. The radiodensity of substances such as wood, plastic, and vegetative material are so low that imaging frequently misses them. However, wood is often visible on magnetic resonance imaging (MRI). An increasing body of literature supports use of ultrasound to detect the presence of radiolucent foreign bodies. However, most foreign bodies in the head and neck are discovered in the course of a detailed history, careful examination, and meticulous wound exploration. Loupe or microscope-assisted magnification is often helpful.

Embedded debris in a wound bed may require gentle scrubbing for complete removal. This must be balanced against the potential for additional disruption of tissue. However, traumatic tattooing can easily occur when pigmented debris left in the wound bed is subsequently covered by epithelium as the wound heals. This is most noticeable when debris is left embedded in dermis that has been denuded of epithelium. Judicious use of solvents, such as acetone, may even be necessary to help remove petroleum-based products. Time spent removing debris likely to cause permanent pigmentation will benefit both patient and physician in that delayed treatment of traumatic tattooing is difficult and often has disappointing results ( Fig. 19.2 ).

Repair

Throughout the assessment and repair of injuries, clear communication with the patient and any attendant friends or family is essential. Informed, written consent should be obtained before repair. It is also important to help the patient set reasonable expectations for the outcome, keeping in mind that for more severely injured patients, treatment of their injuries will likely constitute a process rather than a single event. Although potentially distressing, allowing patients and their families to see the injuries, either with a mirror or photograph, often aids in this endeavor. Ideally, photo documentation should be performed throughout the encounter; images of the wound should be obtained at presentation, after prepping, and again after repair. Photographs are a key component of the medical record for both medical and legal reasons but also for patient education. Patients who are not able or willing to gain an assessment of their wounds before repair will have an opportunity to better understand the extent of their injury by reviewing the photographs at a later time.

Depending on the nature of the wound, a great deal of the surgeon's work can easily be degraded by poor wound care from other health care providers, family, and patients. It is important to educate all parties involved regarding the appropriate wound care regimen. For example, abrasions depend as much on ongoing wound care for optimal healing as they do on initial cleaning and débridement. Close follow-up in the acute phase is, therefore, often necessary, especially in multiply injured patients in whom wound care can sometimes suffer at the expense of efforts to treat more severe injuries.

The first step to performing a technically successful repair is preparation of the work environment. Excellent lighting, comfortable positioning for both the patient and physician, appropriate instruments for soft tissue work in the face, available support staff, and adequate anesthesia are all essential. The absence of any of these elements compromises the primary focus of the surgeon. If necessary, the patient may be transferred to an appropriate venue for repair, such as the operating room or minor procedure room. Facial soft tissue work demands instrumentation such as fine-tooth forceps, small needle holders, skin hooks, tissue scissors, suture scissors, and a scalpel handle with replaceable No. 15 and No. 11 blades ( Fig. 19.3 ). Loupe magnification is also often helpful in improving the precision of repair.

A variety of suture materials and tissue adhesives are available for closure, the choice of which depends upon characteristics of the wound, the patient, and the surgeon. Deep suturing is usually performed with interrupted, inverted, absorbable sutures, although permanent sutures may be used sparingly when deep closure is subject to ongoing forces of tension or muscle contraction. Commonly used absorbable sutures for deep closure include polyglactin 910, polyglecaprone 25, polydioxanone 2, polytrimethylene carbonate, Polysorb, and Caprosyn.

Epithelial closure is commonly performed with permanent monofilament sutures such as 6-0 or 7-0 nylon or polypropylene. Absorbable suture with minimal tissue reactivity, such as fast-absorbing gut, is also useful, especially in children or in patients in whom suture removal may be difficult. A child who requires sedation for repair is unlikely to tolerate the removal of permanent sutures. Similarly, adult patients who are unwilling, unable, or unlikely to follow-up for suture removal are better served with absorbable sutures than permanent sutures left in too long or removed by inexperienced hands.

Tissue adhesives now have a proven role in wound closure, with acceptable results compared with suture techniques in simple lacerations. Even though caution is appropriate in entirely sealing off a heavily contaminated wound, such as a human or animal bite, no evidence suggests that routine lacerations appropriately cleaned and irrigated have increased rates of infection with tissue adhesive than with suture. They can even be combined with fast-absorbing gut on skin to prevent premature suture removal. However, there are limitations. Octyl cyanoacrylate combined with a subcutaneous 4-0 Vicryl closure has approximately the same tensile strength of percutaneous 5-0 nylon suture and cannot be relied upon to close a wound on tension without some widening of the scar. For tissue adhesives to be used effectively, epithelial edges must sit in good approximation before application to prevent glue from entering the wound, resulting in a wider scar or even wound breakdown. Eversion of the wound edges is more difficult with adhesives.

Eversion is critical to the favorable appearance of the final result. Because scars contract as they heal, a laceration that is flat when reapproximated will become inverted. An inverted scar, unless coincidentally located in a wrinkle, will create an obvious shadow and will be easily noticed. The best technique for everting the edges of a wound is to use vertical mattress sutures. Properly placed, these sutures elevate the incision just enough to counteract scar contracture. The distal pass of the needle should be placed perpendicular to the surface of the skin and should be placed one-half the chord length of the needle from the incision; chord length is the distance from the tip of the needle to the swage. The proximal pass of the needle should include only enough of the epidermis to align the edges and reapproximate them. A common technical error is to place the distal pass too close to the laceration and the proximal pass too far away. This has several negative effects. First, very little skin supports the suture, and as the wound swells, the tension causes the suture to act as a seton, creating suture tracks. Second, the epidermal edges will not be in apposition, which results in a gap that granulates and reepithelializes, creating a red, shiny scar ( Fig. 19.4 ).