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SECTION Wound Evaluation Adam J. Singer Judd E. Hollander PRINCIPLES OF INITIAL EVALUATION Evaluation of the patient with a traumatic wound begins with overall patient assessment. 1-3 Less obvious but more serious life-threatening injuries need care before directing attention to wound management. Determine the patient’s past medical history and circumstances sur rounding the injury. 1,2 Remove rings or other circumferential jewelry as soon as possible so they do not act as constricting bands when swelling progresses. Remove clothing over the injured area to reduce the poten tial for contamination. External bleeding can usually be controlled by focal direct pressure over the bleeding site. When possible, replace skin flaps to their original position before applying pressure in order to avoid exacerbating vas cular compromise. Tourniquet application may be necessary to stop life-threatening exsanguination or when needed for a short period to create a “bloodless” field for wound inspection. 4,5 Amputated fingers or extremities should be wrapped with a moist, sterile, protective dressing, placed in a waterproof bag, and then placed in a container of ice water for preservation and consideration for future reattachment. Before wound exploration, cleansing, and repair, most patients will need some form of anesthesia. 6 Systemic analgesia or procedural sedation may be required (see Chapter 35, “ Acute Pain Management, ” and Chapter 37, “Procedural Sedation and Analgesia in Adults”). RISK ASSESSMENT Proper wound management begins with a pertinent patient history (Table 39-1). 1,2 A variety of patient factors have adverse effects on wound healing and increase the rate of wound infection—extremes of age, diabetes mellitus, chronic renal failure, obesity, malnutrition, the use of immunosuppressive medications, the presence of connective tis sue disorders, and protein and vitamin C deficiencies. 1 Predictive factors for infection are the wound characteristics of mechanism of injury, location, depth, length, configuration, and contamination.7-9 Ascertain the tendency of patients to form hypertrophic scars or keloids by both history and examination, as past experience may predict poor scar formation. Black and Asian patients are more prone to keloid formation than whites. Hypertrophic scars are due to tissue tension during wound healing, and these scars stay within the original wound boundaries and tend to undergo partial spontaneous regression within 1 to 2 years. Keloids are genetically linked variations in wound healing, resulting in the production of excess collagen beyond the original wound boundaries (Figure 39-1). Once formed, keloids rarely decrease in size. Obtain a detailed history of allergies or prior adverse reactions to anesthetic agents or antibiotics. Review any prior allergies to latex. Determine the status of prior tetanus immunization and the need for further tetanus vaccination (see Chapter 157, “Tetanus”). Review the mechanism of injury to determine the risk for potential wound contaminants and foreign bodies. Bite wounds have higher risk for infection and are generally managed differently than other lacera tions (see Chapter 46, “Puncture Wounds and Bites”). Foreign bodies are more common in puncture wounds, wounds associated with broken glass, and motor vehicle collisions. 11,12 Ask about the presence of a for eign body sensation.

nds have higher risk for infection and are generally managed differently than other lacera tions (see Chapter 46, “Puncture Wounds and Bites”). Foreign bodies are more common in puncture wounds, wounds associated with broken glass, and motor vehicle collisions. 11,12 Ask about the presence of a for eign body sensation. In adults, those reporting a foreign body sensation are more likely to have a retained foreign body than those who do not. This question has little utility in children.14 Both foreign body retention and visible contamination increase the risk of infection.7,8 Organic and inorganic components of soil can cause infection even from very small doses of bacterial inoculum. Clay is the major inorganic soil component responsible for promoting infection. Conversely, sand grains and black dirt from roadways are relatively inert. The likelihood of wound infection varies according to the forces applied at the time of injury. 7,8 The most common mechanism for traumatic wounds is blunt force. The skin is crushed against underlying bone and tears or splits from the subsequent tension. Conversely, sharp objects produce shear forces that cut skin cleanly. Severely crushed injuries producing extensive tissue devitalization are more susceptible to infection than wounds from shear forces. However, these distinctions may not be clinically relevant when appropriate principles of wound care are used, as was observed in a multicenter observational study that did not find higher rates of infection in blunt versus sharp injuries. Low-energy impact injuries may not result in lacerations, but instead may disrupt vessels, leading to ecchymosis or hematoma formation. Some hematomas spontaneously resorb. Those that become encapsu lated may eventually require aspiration or incision and drainage. Determine the time that the injury occurred. Although the growth of the bacterial inoculum is directly related to the time interval from injury to laceration repair, there is no clearly defined relationship of time to closure to clinical infection 9,15-17 (Table 39-2). Therefore, time from injury until presentation is only one element to be considered, in addition to the injury mechanism, location, degree of contamination, host risk factors, and the importance of cosmetic appearance, before determining whether or not to perform primary wound closure. The aforementioned multicenter observational study 9 confirmed that a his tory of diabetes, visible contamination, length greater than 5 cm, and non–head-and-neck location are associated with higher rates of infec tion. However, there was no association between time from injury to wound closure and the development of infection. 9 Wounds that are not closed primarily because of a high risk of infection should be considered for delayed primary closure after 4 days. The consensus of wound-care experts is that after 4 days of open wound management, the risk of infection after closure substantially decreases, although this approach has not been subjected to randomized controlled trials. Determine whether the wound was the result of an intentional, unintentional, or workplace event. Most states have regulations that require the reporting of intentional injuries, and patients with self-inflicted injuries may need psychiatric evaluation. Occupational injuries may require alternative follow-up arrangements. The anatomic location of the injury helps predict the clinical outcome, both in terms of infection risk and cosmetic result (Table 39-3). 7-9,19 The risk of infection is determined largely by the interplay between baseline bacterial colonization and vascular blood supply. With respect to bacterial colonization, the density of the bacterial population is low on the upper arms, legs, and torso.

h in terms of infection risk and cosmetic result (Table 39-3). 7-9,19 The risk of infection is determined largely by the interplay between baseline bacterial colonization and vascular blood supply. With respect to bacterial colonization, the density of the bacterial population is low on the upper arms, legs, and torso. Conversely, moist areas of the body, such as the axilla, perineum, toe webs, and intertriginous areas, harbor millions of bacteria per square centimeter, including anaerobes. 20 Obviously, any wounds with human or animal fecal contaminants run a high risk of infection, even with therapeutic intervention. Wounds located on highly vascular areas, such as the face or scalp, are less likely to be infected than wounds located in less vascular areas. 7-9 The increased vascularity of the area more than offsets the high bacterial inoculum found in the scalp, and lacerations of the CHAPTER Wound Management Tintinalli_Sec06_p0267-0328.indd 267 8/2/19 7:14 PM

lar areas, such as the face or scalp, are less likely to be infected than wounds located in less vascular areas. 7-9 The increased vascularity of the area more than offsets the high bacterial inoculum found in the scalp, and lacerations of the CHAPTER Wound Management Tintinalli_Sec06_p0267-0328.indd 267 8/2/19 7:14 PM 268 SECTION 6: Wound Management scalp and face have a very low infection rate regardless of the intensity of cleansing.9,21 Although prophylactic oral antibiotics have traditionally been considered as warranted for intraoral lacerations, there is inconclusive evidence to support their use,22 and practice varies considerably.23 WOUND EXAMINATION Thorough wound examination should be conducted when the patient is calm and cooperative and positioned appropriately, with optimal lighting conditions, and with little or no residual bleeding. The use of magnifying lenses, such as surgical loupes (×2.5) or reading glasses, may improve visualization and reduce the likelihood of missing foreign bodies. Cursory examination under poor lighting or when the depths of the wound are obscured by blood will occasionally result in poor detection of foreign bodies and tendon, nerve, and vascular injuries. If bleeding is a problem, epinephrine-containing anesthetic solutions may be helpful, when not contraindicated. Tourniquets may be used to obtain a bloodless field, but they should not be used for more than 30 minutes . Lacerations over joints may have penetrated the joint capsule, and sometimes it is necessary to inject the joint with normal saline to ensure that there is no communication between the joint space and the laceration. Evaluate the wound in neutral position, throughout the full range of motion, and particularly in the position present during injury. Chainsaw knee wounds, for example, are often sustained with the knee in flexed position. Repositioning the joint or extremity in the position assumed during injury can better reconstruct the mechanism of injury and identify injured structures. Lacerations over the metacar pophalangeal joints are suspicious for having occurred during a fight (clenched fist injury) and should be treated as though they are human bites. IMAGING Although most lacerations will not require any diagnostic testing, on occasion, wound imaging for detection of foreign bodies may be neces sary (see Chapter 45, “Soft Tissue Foreign Bodies”). Most foreign bodies commonly found in wounds are much denser than the surrounding tissue and are readily apparent on plain radiographs. 26 Metal, bone, teeth, pencil graphite, certain plastics, glass, gravel, sand, some fish bones, some painted wood, and most aluminum are visible on plain radiographs. CT and MRI are useful for identifying and locating objects that have densities similar to soft tissue. 27,28 US may also be useful, particularly for wooden foreign bodies, although the sensitivity of US is inadequate to FIGURE 39-1. A large keloid extending beyond the original wound margins. [Repro duced with permission from Park CW, Juliano ML, Woodhall D: Wounds and soft tissue injuries, in Knoop KJ, Stack LB, Storrow AB, Thurman RJ (eds): Atlas of Emergency Medicine , 4th ed. Figure 18-41. Copyright © 2016, by McGraw-Hill Education.

IGURE 39-1. A large keloid extending beyond the original wound margins. [Repro duced with permission from Park CW, Juliano ML, Woodhall D: Wounds and soft tissue injuries, in Knoop KJ, Stack LB, Storrow AB, Thurman RJ (eds): Atlas of Emergency Medicine , 4th ed. Figure 18-41. Copyright © 2016, by McGraw-Hill Education. All rights reserved.] TABLE 39-1 Pertinent Medical History •   Symptoms •   Pain, swelling, paresthesias, muscle weakness •   Type of force causing injury •   Crush (blunt) or shear (sharp) •   Bite or puncture •   Elements of contamination •   Time elapsed from injury until initial cleansing •   Time elapsed from injury until presentation •   Wound care performed prior to ED arrival •   Object that caused injury (glass, wood, etc.) •   Cleanliness of body and environment at time of injury and afterward •   Factors resulting in injury •   Intentional or unintentional •   Occupation or nonoccupation related •   Assault or self-inflicted •   Foreign body potential •   Did the object break or shatter? •   Foreign body sensation •   Removal of portion of object •   Function •   Occupation and handedness •   Allergies •   Anesthetics, analgesics, antibiotics, and latex •   Medications •   Chronic medical conditions that increase risk of infection •   Chronic medical conditions that increase likelihood of poor wound healing •   Previous scar formation (hypertrophic scars or keloids) TABLE 39-2 Risk of Wound Infection as Function of Time From Injury to Closure Reference Comments Distinction Between Early and Late Closure (h) Infection Rate/Inadequate Healing With Early Closure Infection Rate/Inadequate Healing With Late Closure Percent Difference (95% CI) Berk et al, 1988 16 All locations 19 8/97 (8.2%) 25/107 (23.4%) 15.1% (5.4% to 24.8%) Head 19 2/44 (5%) 1/36 (3%) −1.8% (−9.9% to 6.4%) Trunk and extremities 19 6/53 (11.3%) 24/71 (33.8%) 22.5% (8.6% to 36.4%) Baker and Lanuti, 199016 Children, 59% head and neck location 6 32/2665 (1.2%) 2/147 (1.3%) 0.16% (−1.76% to 2.08%) Van den Baar et al, 2010 17 Adults, all locations, sutured 6 30/363 (9.1%) 3/45 (6.7%) −1.6 (−6.2 to 9.4) Quinn et al, 2014 9 All locations, sutured wounds 6 5/135 (3.7%) 43/1443 (3.0%) 0.7% (−1.6% to 5.5%) Tintinalli_Sec06_p0267-0328.indd 268 8/2/19 7:14 PM