**3. Basic wound management**

Determining whether a wound should have primary versus delayed closure remains controversial [3, 9]. Traditionally, it was suggested that wounds should be left open for fear of the increased risk of wound infection when sutured closed [3, 9]. Treatment initially involved daily dressings with antibacterial ointment or hydrogen peroxide, followed by secondary closure 2–7 days later [3]. However, other more recent studies have found that there was no significant difference in infection rate between primary and delayed closure of dog bite wounds [3]. These studies advocate that early washout, debridement, and primary wound closure leads to similar infection rates but improvement in cosmetic and functional results [3, 9]. Two particular scenarios universally recommend delayed closure: if the bite is a puncture wound rather than a laceration, and if more than 12 hours has elapsed before the patient is seen by a medical professional [3].

#### **3.1 Antibiotic regimen**

Antibiotic prophylaxis is recommended for high-risk bites. These include presentation 8+ hours after the bite, moderate to severe wounds, patients who are immunocompromised or diabetic, deep puncture wounds, or bites involving the hand or face [3]. No prophylaxis is necessary for scratch wounds. Some studies suggest the use of antibiotic prophylaxis for infants and patients older than 50 years, irrespective of the appearance of the wound [3]. The first-line therapy (see **Table 1**) for both prophylaxis and treatment of dog bites is oral amoxicillin-clavulanate [3, 4, 9]. If the patient has a penicillin allergy, oral extended-spectrum cephalosporins (ceftriaxone, cefotaxime) or trimethoprim-sulfamethoxazole plus clindamycin is recommended [3, 4, 9]. For more severe wounds, consider intravenous ampicillin-sulbactam or meropenem [3, 4, 9]. If the patient seems to be worsening under the coverage of ampicillin-sulbactam, consider adding MRSA coverage with either trimethoprim-sulfamethoxazole or clindamycin


#### **Table 1.**

*Antibiotic management of dog bite injuries based on type of infection1*

based on the hospital's local resistant patterns [4]. If the patient requires hospitalization, vancomycin would be the additional antibiotic of choice for MRSA coverage [4]. The length of time recommended for prophylactic treatment is 3- to 5-days, with close follow-up in 24–48 hours to monitor for signs of developing infection [4]. For a soft tissue infection, a 7- to 10-day course of therapy is typically sufficient [4, 9]. However, a 10- to 14-day course may be warranted for more severe infections [4, 9].

*.*

#### **3.2 Wound care**

Approximately 5–25% of all dog bite wounds in children become infected [10]. The bites most likely to become infected include deep (puncture) contaminated wounds; areas marked with tissue destruction, poor perfusion, or edema; attacks to the hands, feet, face, or genitals; and wounds with joint involvement [9–11]. Wound infections after a dog bite are usually polymicrobial and consist of both aerobic and anaerobic bacteria from the mouth flora of the biting animal [9–11]. An average of 2–5 different bacterial isolates per culture were reported in a series of infected wounds caused by dog bites [9, 11]. *Pasteurella spp*. are the most common pathogen isolated and are found to have high carriage rates in the oropharynx, making bite wounds an easily transmittable method for infection [9–11]. Other pathogens identified in dog bites include, but are not limited to, *Corynebacterium* group G, *Neisseria weaveri*, *Capnocytophaga canimorsus*, *Fusobacterium nucleatum*, *Bacteroides tectus*, *Prevotella heparinolytica*, *Propionibacterium acnes*, *Peptostreptococcus anaerobius*, *Streptococcus pyogenes*, *Staphylococcus aureus*, and *Moraxella catharralis* [9, 11]. *Pasteurella* species were found to have the shortest latency period between bite and onset of infection [11]. They are also more commonly cultured from abscesses compared to the other species listed above [11]. The second most common bacterium isolated from dog bites was a tie between *Staphylococcus* and *Streptococcus* species [11]. Both were notable for being found most frequently in nonpurulent wounds, such as cellulitis and lymphangitis [11].

Signs of infection can present within hours to days of the initial bite and may include pain, erythema, and/or swelling of the affected area [9–11]. A multicenter, prospective study of 50 dog bite wounds found that the majority of infections were purulent without abscess formation (58%), followed by nonpurulent wounds with cellulitis, lymphangitis, or both (30%), and abscess formation resulting in the smallest number of presenting infections (12%) [11].

*Current Concepts: Pediatric Dog Bite Injuries DOI: http://dx.doi.org/10.5772/intechopen.102329*

Treatment of the wound should begin with gentle irrigation using normal saline. The amount depends on the size and nature of the wound but typically ranges from 250 to 500 mL, or 50 to 100 mL/cm of laceration [4, 10, 11]. A 20 mL or larger syringe or catheter should be used to ensure enough pressure is applied to properly clean the wound [4, 10, 11]. If the wound is large or complex, surgical evaluation may be necessary to fully examine the wound for neurovascular, muscular, and soft tissue damage. A radiograph may be necessary if there is a concern for fractures or broken teeth or deeper puncture wounds concerning the development of osteomyelitis [4, 10].

#### **3.3 Wound closure**

Based upon the nature and characteristics of the injury, there are multiple options for wound closure. As previously discussed, there is intense debate surrounding primary vs. secondary closure of dog bite injuries. Once a decision has been made if or when the closure is necessary, there are several options on the technique of closure. The gold standard for wound closure is suturing [12]. Non-absorbable sutures are more applicable for partial-thickness wounds that can be easily released after healing [12]. Absorbable sutures are used for deeper or full-thickness wounds as a double-layer of closure and to decrease the tension on the primary sutures above [12]. Once the type of suture has been determined, the technique for suturing needs to be decided. Simple interrupted sutures tend to be more cosmetically appealing and allow for a better approximation of the wound edges [12]. However, if there is a need for rapid hemorrhage control or an extensive wound, running sutures allow for quick application but have a greater risk of dehiscence [12]. Finally, mattress stitches should be applied to deeper wounds due to their ability to employ deeper penetration with greater strength of wound closure [12]. In children, the use of an adhesive such as skin glue or skin tape can be considered but remains controversial in the context of dog bite wounds [12]. These options are excellent for percutaneous wounds and allow for less painful procedures, both with placement and removal. Another option for wound closure are staples, which can be placed quickly and are most useful in settings with brisk bleeding [12]. If there are multiple non-facial lacerations, staples are an efficient, cost-effective, and simple technique but may not be ideal for cosmesis.

#### **3.4 Scar management**

There are varying opinions on the appropriate recommendations for scar prevention and management. However, the initial step is to ensure proper primary suturing technique with the absence of tension on the wound and accurate approximation of the wound edges [12–15]. The wound should be closed with as little traction as possible and force should be minimized to cause further tissue damage [13–15]. Refer to **Table 2** for recommendations on when sutures should be removed for complete healing [12–16]. Skin tape can be applied to the area to continue to reduce tension and antibiotic ointment is no longer needed [12]. The following days to weeks after the initial injury, wound hydration becomes crucial [13–15]. Daily to every other-day dressing changes and cleaning with saline or tap-water is vital [13–15]. Never use alcohol or iodide solutions because of their cytotoxic nature, which inhibits healing and increases scar formation [13–15]. Silicone gel sheeting has also been shown to be effective in the treatment and prevention of scars by increasing hydration and decreasing collagen deposition [14, 15]. If there is a concern that keloid formation will occur, referral to a dermatologist for further management is recommended. There,


#### **Table 2.**

*Suture removal recommendations based on location of injury1 .*

they may recommend intralesional steroid injections, laser therapy, or antimitotic drugs to help prevent or treat keloid and scar formation [15].

#### **3.5 Severe wound management**

When determining which patients are most likely to require hospitalization after being bitten by a dog, there are a few potential risk factors. Male children are more likely to sustain a dog bite than their female counterparts, which also makes them more likely to sustain a bite that requires hospitalization [17]. Additionally, non-Hispanic White children were more likely than their Black, Hispanic, and Asian peers to be hospitalized after a dog bite [17]. The summer months have the highest rate of dog bite hospitalization compared to any other season [17]. Of the children that were hospitalized, approximately 1/3rd required a major surgical procedure consisting of either debridement with suturing of the wound, skin grafting, plastics' surgical intervention, or tissue reconstruction [17]. Overall, the predominant description of children requiring hospitalization after a dog bite were of Caucasian ethnicity, male, less than 10 years of age, and received deep, extended, or multiple sites of injury [17].

#### *3.5.1 Facial*

A 20-year review of dog bites to the head and neck region found that 49.33% were 18 years of age or younger [18]. The majority of the lesions were sustained in the upper lip (32%), cheek (27%), and nose (20%) [18]. Periorbital or orbital wounds were rare [18]. The majority of the wounds were closed with primary methods using either sutures or adhesive strips (63%) due to their uncomplicated nature [18]. However, determining the method of closure should be based on the depth and underlying involvement of the wound. Please see the *Lackmann classification of injury* below for further details on how to classify the extent of a facial lesion. By classifying the lesion using the Lackmann system, it can help a provider to determine prognostic status and best method(s) for management of the wound. A transposition flap or reconstructive surgery was required in a small subset (6.7%) and skin grafting in an even smaller portion (3%) with more severe injuries [18]. Secondary wound infections were reported in only 2.24%, based on the theory that blood flow is enhanced to the face and neck regions leading to decreased incidence of infection [18]. However, it should be noted that prophylactic antibiotics were prescribed in 95% of cases likely contributing to the low infection rate [18].

*Current Concepts: Pediatric Dog Bite Injuries DOI: http://dx.doi.org/10.5772/intechopen.102329*

A second review detailing the otolaryngology perspective on head and neck injuries details that 26.8–56.5% of dog bites occur to the head or neck [19]. Infection rates are reported to be as low as 5.7% due to the vascularized nature of the tissue [19]. The current recommendation is primary closure of head and neck wounds unless the results would be cosmetically displeasing [19]. ENT/OMFS and/or Plastics specialists should be consulted to help with esthetics and determination of closure technique. Additionally, current recommendations require amoxicillin-clavulanate therapy for 3–5 days whenever dog bites involve the face [19]. If signs of infection develop, the course should be extended to 7–14 days [3–4, 9, 19].
