The principles of soft tissue wound management are careful examination of the patient and assessment of the injury, followed by meticulous sharp debridement, irrigation, and defect closure with repair of any specialized structures such as nerves and ducts. Inadequate debridement can lead to permanent tattooing of the skin. An example is road rash in a partial-thickness abrasion, where gravel left in the wound will be permanently visible as black pigment. Although local anesthetic is useful to helpfully assess and treat many wounds, it must not be used until nerve function has been assessed as it may mask underlying injury. Although all patients should have their tetanus status checked, not all will need further tetanus doses. Current guidelines differ, with some advocating a booster every 10 years or at the time of an injury if no booster has been given within a 5-year period.1 Even patients with tetanus-prone injuries do not require boosters, providing they have undergone complete immunization and received a booster within 5 years. There is often confusion regarding descriptions for soft tissue wounds. An abrasion is a scraped area of skin but may be partial or full thickness. Partial-thickness abrasions are generally treated with dressings, while full-thickness abrasions may require formal excision and direct closure, skin grafting, or flap coverage depending on size and location. Local flaps are not generally recommended for use in the acute setting, especially in wounds with crush components and should therefore be preserved for secondary reconstruction.2,3
The most common pathogens implicated in infection in human bites are Eikenella corrodens and Streptococcus viridans, so antibiotics should be selected to target these organisms. Amoxicillin alone is not a suitable antibiotic for bite injuries and needs to be combined with clavulanate (Augmentin) to provide extended spectrum beta lactam coverage. Most bite injuries should be left open to heal after debridement, but bites to the face should be closed primarily after debridement. An exception to this rule is where there is evidence of active infection. In this case, delayed primary closure is indicated after debridement and antibiotic treatment. Pasteurella canis and Pasteurella multocida are frequently associated with canine and feline bites, respectively. Although human bites can lead to severe infections, cat bites are most commonly associated with infection because of the deep, puncture type wounds and the virulent bacteria involved.1–4
3. Update on adult immunization. Recommendations of the Immunization Practices Advisory Committee (ACIP). MMWR Recomm Rep 1991;40(RR-12):1–94
4. Looke D, Dendle C. Bites (mammalian). BMJ Clin Evid 2015; 2015: 0914. Published online December 4, 2015 MANAGING SCALP WOUNDS 3. Which one of the following methods of wound closure is recommended for the skin of the hair-bearing scalp to minimize alopecia? When closing scalp defects a layered approach is advised so the galea is approximated with interrupted absorbable sutures before skin closure. Skin closure can then be achieved with any of the above sutures; however, staples may cause the least tissue necrosis, provide adequate wound-edge eversion, and less subsequent scalp alopecia than other forms of closure.1,2 Another advantage to staples is the ease and speed with which they can be placed. This is particularly useful in reducing bleeding from scalp wound edges. A disadvantage is that some patients find it painful when they are being removed. This can be minimized by ensuring the clips are fully opened before attempting to remove them. Alopecia may be further minimized by careful use of cautery at the wound edges. When planned incisions are made in the scalp, beveling the blade may also help reduce alopecia as this allows hair regrowth through the scar.
The lacrimal apparatus is clinically relevant to soft tissue facial trauma as it can be damaged during periorbital injuries. Tears drain from the upper and lower eyelids through puncta and then pass along the superior or inferior canaliculus respectively to the common canaliculus and on toward the lacrimal sac. The lacrimal sac drains into the lacrimal duct and then enters the nasal cavity at the valve of Hasner. Injury to the ductal system is most commonly seen with lower medial eyelid injuries and will result in epiphora. It can be managed with surgical repair over a stent by the ophthalmology team. Dacryocystorhinostomy (DCR) may be necessary if cannulation is impossible and injury leads to persistent and problematic epiphora (Fig. 34.1).1,2 Fig. 34.1 The lacrimal system is made up of superior and inferior canaliculi that coalesce into the common canaliculus. This empties into the lacrimal sac, which drains into the nose through the lacrimal duct. The upper system is composed of the superior/inferior puncta through the common canaliculus, and the lower system consists of the lacrimal sac and duct. (From Marcus JR. Essentials of Craniomaxillofacial Trauma. St Louis: Quality Medical Publishing, 2012.) Superior canaliculus Lacrimal sac Lacrimal duct Valve of Hasner Inferior Superior and inferior puncta
Avulsion injuries of the scalp are common and often referred to plastic surgery for evaluation and management. The soft tissues of the scalp have five layers: skin, subcutaneous tissue, galea, loose areolar tissue, and pericranium. Avulsion injuries most commonly occur at the level of the scalping plane between the galea and pericranium.1,2 Other common injury types in the scalp are burst injuries in young children. With this mechanism of injury the patient falls onto the head and bangs it on a furniture corner or the floor. Wounds are deep and often pass down to the frontal bone, stripping a small amount of pericranium just above the brow. In some instances, these injuries cause an underlying fracture, and this should be excluded. Scalping injuries down to the temporal bone are rare because this anatomic area has multiple robust layers of soft tissue including temporalis, deep, and superficial temporal fascia as well as skin and subcutaneous fat. Wounds should be examined under anesthesia, debrided, and closed in layers with absorbable sutures (Fig. 34.2).
This patient is at risk of damage to any of the five main branches of the facial nerve and therefore can have symptoms ranging from mild to complete unilateral facial paralysis. The paralysis can account for a loss in oral competence, which may be amplified by damage to the buccinator muscle itself.1 Although the wound is not full thickness, saliva can be present because of injury to the parotid gland or division of the parotid duct (Stensen’s duct).2 The auriculotemporal branch of the trigeminal nerve is at risk of injury. This supplies the superior lateral aspect of the ear. Sensation to the lobule should be spared because this is supplied by the great auricular nerve.3
Use of skin preparations prior to surgery should be undertaken with care, particularly when working on the head, neck, and face. The safest preparation to use is aqueous iodine as this clearly marks the areas prepared, and is virucidal and bactericidal yet is nontoxic to the eyes. Chlorhexidine is also bactericidal but is toxic to the cornea so care must be taken to avoid the eyes. Hydrogen peroxide is weakly bactericidal, but is not used as a skin preparation. Many surgeons like to use it to clean wounds and, in particular, the skin as it effectively removes dried blood. The use of saline or water will be most effective as irrigation agents to dilute and wash contaminated wounds as they are obviously both safe to use around the face. However, they do not possess bactericidal qualities and are therefore not effective skin preparations to form a sterile field.1
The use of nerve blocks to facilitate facial surgery can be very useful in both the emergency and elective settings. Nerve blocks allow larger areas of anesthesia with fewer needle sticks and less volume and consequent swelling compared with field blocks. This is important for patient’s comfort and experience as well as minimizing swelling so that tissues can be accurately apposed or reconstructed. Sensation to the face is provided by the three divisions of the trigeminal nerve (cranial nerve [CN] V) as well as C2–C4 cervical roots of the cervical plexus. Therefore, even with blockage of CN V there will be some sensation remaining. The midpupillary line is a useful anatomic landmark for nerve blocks because it guides the horizontal position of the supraorbital, infraorbital, and mental nerve foramina. The ear requires a field block rather than a single nerve block because it has multiple innervations from the great auricular, auriculotemporal, lesser occipital, vagus, and facial nerves. The zygomaticotemporal nerve is best blocked using a small needle such as a 30 gauge with 1-inch length to be passed deep-to-deep temporal facia and will provide anesthesia to the temple region. It is generally combined with a zygomaticofacial nerve block. A mental nerve block targets the mental nerve and is directed intraorally in the buccal sulcus at the level of the second premolar (not 3rd molar). It provides anesthesia to the lower lip and chin with minor modification.1,2