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Acute Burn Management
4.1 Acute Burn Management Yvonne Karanas
SYNOPSIS Burn care starts at the time of injury with appropriate wound care, fluid resuscitation, and nutrition. Appropriate early management of many burns can prevent infection, allow for healing without surgery, and prevent contracture formation. Knowledge of the burn wound is key to correctly classifying burn injuries and thereby determining which wounds require surgery. Although the fundamentals of surgical burn wound management have not changed significantly in the last 30 years, we now understand that early and aggressive surgery results in higher survival rates and fewer complications. The use of topical antimicrobials has improved with many more options available, so systemic antibiotics can be reserved for true invasive infections. Early physical therapy with range-of-motion exercises and splinting can prevent many of the contractures that result in long-term disability after burn injury. This chapter will focus on the surgical aspects of acute burn management.
CLINICAL PROBLEM Presentation Burn injuries have a variable presentation depending on the depth and mechanism of the injury. Many burns are not of uniform depth, so there will be different degrees of injury in the same burn wound. Burns that involve only the epidermis are classified as first-degree burns and do not warrant special care. Burns that involve the epidermis and a portion of the dermis are classified as second-degree or partialthickness burns. These burns may be moist and pink or have fixed hemoglobin and appear cherry red and dry, depending on the depth of dermal involvement (Fig. 4.1.1). Burns involving the epidermis and entire dermis down to the subcutaneous tissue are third-degree or fullthickness burns (Fig. 4.1.2). These burns are white, yellow, or brown with a leathery texture (Fig. 4.1.3). Lastly, burns extending through the entire dermis into the subcutaneous tissues, muscle, or bone are fourthdegree burns and are the most severe burns that we treat. These burns may present similarly to third-degree burns, and it is not until excision is performed that the depth is appreciated. Alternatively, they may present with black, charred eschar and exposure of the underlying structures. Patients presenting with burn injuries should have their wounds classified using the terminology described earlier.
Etiology Burn injuries can be described by the source of the heat: scald, flame, contact, and chemical (Fig. 4.1.4). Although the mechanism of the injury may be different, the end result is the same with injury to the
228
skin. Loss of a portion of the skin leads to lack of temperature regulation, fluid and protein loss, electrolyte imbalance, and a propensity for infection. Electrical injuries must be differentiated from other burn injuries due to their propensity for significant internal damage. The electrical current can travel through the body, emitting thermal energy internally. The cutaneous injury may be relatively small, whereas the underlying tissue necrosis may be extensive.
Associated Conditions Burn injuries may result from a traumatic event such as a motor vehicle accident or explosion. These events put the patient at risk for concomitant traumatic injuries. The acute burn victim must be assessed for other injuries if the mechanism of the accident suggests that other injuries may be present. Burn victims who are trapped in a house fire or other enclosed space have a risk for inhalation injury. Mechanical ventilation, bronchoscopy, and aggressive pulmonary care may be needed in addition to the care of the cutaneous burn injury. Burn victims with diabetes and peripheral vascular disease who sustain lower-extremity and foot burns will have a protracted course and a high risk of limb loss due to inadequate blood flow to the tissues to aid in healing. Elderly burn victims or those with significant medical comorbidities are at risk of death even with small burns under 10% total body surface area (TBSA).
PRE-OPERATIVE MANAGEMENT Physical Examination The depth of the burn injury is determined by physical examination. The color, texture, and moisture of the wound, the presence or absence of capillary refill, and the presence or absence of sensation are all findings on examination that help the physician determine the depth of the injury. Insensate, white, leathery skin that lacks capillary refill has sustained a third-degree burn. Pink, moist skin with brisk capillary refill is characteristic of a superficial second-degree or partial-thickness burn. Second-degree burns should be managed conservatively with wound care. Third- and fourth-degree burns require surgical excision and wound coverage. Deep second-degree burns can be treated conservatively initially to see whether healing will occur. If it becomes apparent over 10 to 14 days that the wound is not healing, then surgery should be performed. Full-thickness burns on the dorsum of the hands and feet, over the elbow, or over the anterior tibia should alert the physician that exposure of tendons or bones may occur with tangential excision. The surgeon should be prepared to manage these situations should they occur.
CHAPTER 4.1 Acute Burn Management
229
FIG. 4.1.4 An example of a contact burn on the palm of the hand. FIG. 4.1.1 An example of a second-degree burn.
repleted as necessary.1 In addition, the patient’s coagulation profile should be assessed, and fresh frozen plasma and platelets should be made available as needed.
Optimal Timing of Surgery
FIG. 4.1.2 An example of a third-degree burn.
For full-thickness burns, surgery should occur as soon as the patient is resuscitated and is hemodynamically stable. This is usually 24 to 72 hours after injury. The wound will not improve without excision, so surgery should commence as soon as safely possible.2 For deep partial-thickness burns, it may be difficult to determine initially whether the wound will heal in a timely fashion or whether it will require surgery. The surgeon’s goal is for the wound to be healed in 3 weeks. If the surgeon is unsure whether surgery is required, a period of waiting is recommended. By 10 to 14 days post-burn, the surgeon should be able to determine whether surgery is required for healing by day 21.
Supplies Needed
FIG. 4.1.3 Another example of an even deeper third-degree burn.
Pre-Operative Testing Needed No specific testing is required for evaluation of the burn wound. In major burns (>20% TBSA) the hemoglobin or hematocrit should be checked before surgery and a crossmatch performed in anticipation of the need for a blood transfusion. Electrolytes should be monitored and
Watson knives Weck knives Epinephrine-soaked sponges: 5 cc 1/1000 epinephrine per 1 L normal saline Electrocautery Dermatome Mesher Burn dressings Tumescent solution: 1 liter lactated Ringer’s or normal saline, 1 cc 1:1000 epinephrine, 30 cc 0.25% Marcaine (Figs. 4.1.5 and 4.1.6)
Anesthesia Concerns Airway management in the burn victim can be extremely challenging. Edema of the surrounding tissues can obscure normal structures and make standard endotracheal intubation impossible. For patients with extensive burns to the head and neck or large TBSA burns, we recommend early intubation before the onset of edema. Edema will obliterate
230
SECTION 4 Burns
FIG. 4.1.5 Typical dermatome setup with multiple guards allowing different widths of skin graft harvest.
normal tissue while removing all burned tissue.1,3 The surgeon will select the Watson or Weck knife based on the size, depth, and location of the burn and on the thickness of the skin in that anatomical area. Large, deep burns on the torso and upper and lower extremities are excised with the Watson knife. Smaller burns or wounds on the hands and feet are excised using the Weck knife. The depth of the excision can be adjusted by the guard on the Weck knife. There are three standard guards with depths of 0.08, 0.10, and 0.12 inches. The Watson knife has an adjustable depth that is controlled by the surgeon to allow for deeper or more superficial excisions as the situation warrants (Video 4.1.1). The knife is held at a 45-degree angle to the skin, and the eschar is incised. The blade angle is then decreased to ~30 degrees. The blade is moved back and forth like the bow on a string instrument with gentle pressure moving it forward to lift the eschar off of the wound. Once the initial layer of the eschar is removed in this fashion, the wound bed is assessed for viability. A pearly-white dermis, light-yellow fat with punctate bleeding, and patent blood vessels indicate adequate excision. Ecchymosis within the tissue, brown discoloration of the fat, and lack of bleeding indicate that additional excision is required. The procedure should be performed repeatedly until the signs of a healthy wound bed described earlier are appreciated (Videos 4.1.2 and 4.1.3).4 Epinephrinesoaked sponges should be applied to the wound bed as soon as excision is complete. Large venous or arterial bleeding should be controlled with the electrocautery, sutures, or Hemaclips. Smaller dermal and punctate bleeding can usually be controlled with epinephrine-soaked sponges. Skin grafts can be harvested while the epinephrine solution is taking effect.
Skin Grafting
FIG. 4.1.6 Watson knives (left) and Weck knives (right) used for tangential excision of burn wounds.
normal landmarks, and a surgical airway may become necessary. Once scarring has developed, oral opening and neck extension may be limited, making intubation difficult. Fiber-optic intubation may be necessary in these situations. Burn surgery is often associated with large and rapid blood loss. The amount of blood loss will correlate with the size of the excised area, the presence of infection, and any underlying coagulopathies. Large-bore IV access and ongoing assessment of blood loss are critical to maintaining euvolemia and avoiding shock. Burn patients have difficulty with thermoregulation due to their lack of skin. This becomes pronounced in the operating room when the patient is stripped of dressings, and multiple sites are exposed for excision and donor site harvest. A warming protocol should be developed before surgery so it can be implemented when the patient arrives in the operating room. Warming the room and all fluids, placing a warming blanket under and over the patient during surgery, and wrapping the patient’s head in heated blankets are all techniques used to maintain normothermia during surgery.
SURGERY Tangential excision is the process by which the burn eschar is removed. Janzekovic described this procedure in 1970 with the goal of preserving
An autograft skin graft is the patient’s own skin, composed of the epidermis and a portion of the dermis. Enough dermis is left in the native wound bed for the wound to heal by re-epithelialization. An electric- or air-powered dermatome can be used to harvest the skin graft. The thickness of the graft is determined by setting the thickness of the opening on the blade of the dermatome (Video 4.1.4). Mineral oil is applied to the skin to allow the dermatome to slide smoothly over the skin surface. The dermatome is angled at 60 degrees to the patient’s skin, turned on, and then placed onto the skin (Video 4.1.5). With gentle pressure, the device is slid along the skin at an approximately 30- to 45-degree angle. The surgeon can visualize the graft coming up over the blade of the device, so he/she knows that the machine has adequately engaged the skin. Grafts can be harvested from any area of unburned skin. Large, flat areas yield the best grafts, so the thigh is the first choice for a donor site. Areas with bony prominences can be made smooth by the subcutaneous injection of tumescent solution. Epinephrine and local anesthetics are added to assist with hemostasis and postoperative pain control. The fluid is injected into the subcutaneous tissue until the skin becomes smooth. Grafts can then be harvested in a standard fashion. The skin grafts may then be meshed to allow for coverage of larger surface areas. Grafts should be placed in moist saline sponges until they are ready to be used. Once the wound bed is adequately excised and hemostasis has been achieved, the grafts are applied dermal side down and secured in place using surgical staples.
Escharotomies In cases of severe, deep partial- or full-thickness burns, escharotomies may be necessary. Escharotomy is defined as the surgical incision through the eschar into the subcutaneous tissues to allow the extremity to continue to swell without compressing the underlying blood vessels. Circumferential deep second- and third-degree burns of the extremities can act as a tourniquet and impede blood flow to the distal extremity. Deep burns to the chest and back can cause difficulty with
CHAPTER 4.1 Acute Burn Management
231
FIG. 4.1.7 An example of an upper-arm escharotomy.
FIG. 4.1.9 An example of a chest escharotomy.
FIG. 4.1.8 An example of a leg escharotomy.
chest wall excursion and thereby inhibit ventilation. Escharotomies are performed to release the compression and allow for distal blood flow and/or chest wall movement. Escharotomies are performed using a knife or electrocautery. The area is prepped in the standard fashion. The eschar is then incised down to the subcutaneous fat. Incisions on the upper extremities are made along the radial and ulnar aspects of the arm. In the fingers, midlateral escharotomies are made on the non-contact sides. On the leg, the incisions are made medially and laterally 180 degrees apart. Chest escharotomies are performed in the anterior axillary lines and along the subcostal margin. Usually the skin edges “pop” open due to the underlying pressure in the tissues, indicating adequate release. When complete, the wound edges are usually separated by at least 1 cm. The wound is then dressed in the standard fashion (Figs. 4.1.7–4.1.9).
POST-OPERATIVE CARE Dressings: Skin grafts are dressed with non-adherent gauze and moist antimicrobial dressings. For small, clean wounds, dressings are left in place for 5 days and then wound care reinstituted. For large, contaminated wounds, the dressings are changed on the third postoperative day. Early wound infections can be addressed, and grafts salvaged with this approach. Splinting: Splints are used when skin grafts are placed across joints or on areas of movement. Splints are most commonly used on the extremities, neck, and axillae. The splints prevent movement across joints so that there is no shearing of the grafts during the early
healing period. On post-operative day 5, range-of-motion exercises are begun, and splints are worn only at nighttime to prevent contracture. Therapy: Range-of-motion exercises are begun on post-operative day 5 or sooner if the grafts are completely adherent. Patients with grafts on their legs or feet may begin ambulation if they are able on postoperative day 5. Exercises progress from passive to active range of motion and then to strengthening as tolerated. Early contractures are identified and treated aggressively with therapy. Return to activity: Patients are encouraged to return to their normal activities as soon as possible. Patients with lower-extremity burns often have prolonged edema and pain with standing for long periods of time. Return to work and regular activities is therefore delayed.
MANAGEMENT OF COMPLICATIONS Graft loss: Loss of a skin graft results from infection, inadequate wound debridement, hematoma, seroma, shear, or pressure. Prevention of these factors will help ensure good graft take. Partial graft loss can usually be managed conservatively with wound care, and the area of loss will heal by secondary intention (Fig. 4.1.10). For large graft loss or complete graft loss, a period of wound care is instituted to ensure that the wound bed is adequate. Regrafting is usually performed when conditions are optimized to ensure good graft take. Infection: Bacterial contamination or infection of the wound bed can usually be managed topically with antimicrobial dressings. If a skin graft failed to take because of infection, systemic antibiotics should be considered before a second skin graft procedure. Inadvertent injuries: Although they set the depth of excision, the Weck and Watson knives can cut deeper and injure underlying structures. The surgeon must keep the blade angled to the skin and not press too deeply into the tissues. If the blade is held at a 90-degree angle
232
SECTION 4 Burns KEY PRINCIPLES • Burns are described as first, second, third, and fourth degree based on the depth of injury. • Third-degree burns require surgery to heal. Superficial second-degree burns should not need surgery. Deep second-degree burns may require surgery. • The burn wound should be excised following the principle of tangential excision. Adequate excision and post-operative immobilization are critical to ensure skin graft survival. • Skin grafts should be dressed with antimicrobial dressings until they have healed. • Range of motion should be instituted as soon as the grafts are well adhered to prevent contracture. This usually occurs by post-operative day 5.
FIG. 4.1.10 An example of partial skin graft loss.
to the skin, it will slice directly into the tissues and can easily injure underlying structures. When using the tumescent technique, the surgeon must ensure that the fluid is injected into the subcutaneous space and not the subfascial space. Inadvertent injection into the muscle compartment may result in compartment syndrome.
KEY REFERENCES 1. Baxter CR. Fluid volume and electrolyte changes of the early postburn period. Clin Plast Surg. 1974;1(4):693–703. 2. Gray DT, Pine RW, Harnar TJ, et al. Early surgical excision versus conventional therapy in patients with 20 to 40 percent burns. A comparative study. Am J Surg. 1982;144(1):76–80. 3. Janzekovic Z. A new concept in the early excision and immediate grafting of burns. J Trauma. 1970;10(12):1103–1108. 4. Mosier MJ, Gibran NS. Surgical excision of the burn wound. Clin Plast Surg. 2009;36(4):617–625.
SYNOPSIS Burn care starts at the time of injury with appropriate wound care, fluid resuscitation, and nutrition. Appropriate early management of many burns can prevent infection, allow for healing without surgery, and prevent contracture formation. Knowledge of the burn wound is key to correctly classifying burn injuries and thereby determining which wounds require surgery. Although the fundamentals of surgical burn wound management have not changed significantly in the last 30 years, we now understand that early and aggressive surgery results in higher survival rates and fewer complications. The use of topical antimicrobials has improved with many more options available, so systemic antibiotics can be reserved for true invasive infections. Early physical therapy with range-of-motion exercises and splinting can prevent many of the contractures that result in long-term disability after burn injury. This chapter will focus on the surgical aspects of acute burn management.
CLINICAL PROBLEM Presentation Burn injuries have a variable presentation depending on the depth and mechanism of the injury. Many burns are not of uniform depth, so there will be different degrees of injury in the same burn wound. Burns that involve only the epidermis are classified as first-degree burns and do not warrant special care. Burns that involve the epidermis and a portion of the dermis are classified as second-degree or partialthickness burns. These burns may be moist and pink or have fixed hemoglobin and appear cherry red and dry, depending on the depth of dermal involvement (Fig. 4.1.1). Burns involving the epidermis and entire dermis down to the subcutaneous tissue are third-degree or fullthickness burns (Fig. 4.1.2). These burns are white, yellow, or brown with a leathery texture (Fig. 4.1.3). Lastly, burns extending through the entire dermis into the subcutaneous tissues, muscle, or bone are fourthdegree burns and are the most severe burns that we treat. These burns may present similarly to third-degree burns, and it is not until excision is performed that the depth is appreciated. Alternatively, they may present with black, charred eschar and exposure of the underlying structures. Patients presenting with burn injuries should have their wounds classified using the terminology described earlier.
Etiology Burn injuries can be described by the source of the heat: scald, flame, contact, and chemical (Fig. 4.1.4). Although the mechanism of the injury may be different, the end result is the same with injury to the
228
skin. Loss of a portion of the skin leads to lack of temperature regulation, fluid and protein loss, electrolyte imbalance, and a propensity for infection. Electrical injuries must be differentiated from other burn injuries due to their propensity for significant internal damage. The electrical current can travel through the body, emitting thermal energy internally. The cutaneous injury may be relatively small, whereas the underlying tissue necrosis may be extensive.
Associated Conditions Burn injuries may result from a traumatic event such as a motor vehicle accident or explosion. These events put the patient at risk for concomitant traumatic injuries. The acute burn victim must be assessed for other injuries if the mechanism of the accident suggests that other injuries may be present. Burn victims who are trapped in a house fire or other enclosed space have a risk for inhalation injury. Mechanical ventilation, bronchoscopy, and aggressive pulmonary care may be needed in addition to the care of the cutaneous burn injury. Burn victims with diabetes and peripheral vascular disease who sustain lower-extremity and foot burns will have a protracted course and a high risk of limb loss due to inadequate blood flow to the tissues to aid in healing. Elderly burn victims or those with significant medical comorbidities are at risk of death even with small burns under 10% total body surface area (TBSA).
PRE-OPERATIVE MANAGEMENT Physical Examination The depth of the burn injury is determined by physical examination. The color, texture, and moisture of the wound, the presence or absence of capillary refill, and the presence or absence of sensation are all findings on examination that help the physician determine the depth of the injury. Insensate, white, leathery skin that lacks capillary refill has sustained a third-degree burn. Pink, moist skin with brisk capillary refill is characteristic of a superficial second-degree or partial-thickness burn. Second-degree burns should be managed conservatively with wound care. Third- and fourth-degree burns require surgical excision and wound coverage. Deep second-degree burns can be treated conservatively initially to see whether healing will occur. If it becomes apparent over 10 to 14 days that the wound is not healing, then surgery should be performed. Full-thickness burns on the dorsum of the hands and feet, over the elbow, or over the anterior tibia should alert the physician that exposure of tendons or bones may occur with tangential excision. The surgeon should be prepared to manage these situations should they occur.
CHAPTER 4.1 Acute Burn Management
229
FIG. 4.1.4 An example of a contact burn on the palm of the hand. FIG. 4.1.1 An example of a second-degree burn.
repleted as necessary.1 In addition, the patient’s coagulation profile should be assessed, and fresh frozen plasma and platelets should be made available as needed.
Optimal Timing of Surgery
FIG. 4.1.2 An example of a third-degree burn.
For full-thickness burns, surgery should occur as soon as the patient is resuscitated and is hemodynamically stable. This is usually 24 to 72 hours after injury. The wound will not improve without excision, so surgery should commence as soon as safely possible.2 For deep partial-thickness burns, it may be difficult to determine initially whether the wound will heal in a timely fashion or whether it will require surgery. The surgeon’s goal is for the wound to be healed in 3 weeks. If the surgeon is unsure whether surgery is required, a period of waiting is recommended. By 10 to 14 days post-burn, the surgeon should be able to determine whether surgery is required for healing by day 21.
Supplies Needed
FIG. 4.1.3 Another example of an even deeper third-degree burn.
Pre-Operative Testing Needed No specific testing is required for evaluation of the burn wound. In major burns (>20% TBSA) the hemoglobin or hematocrit should be checked before surgery and a crossmatch performed in anticipation of the need for a blood transfusion. Electrolytes should be monitored and
Watson knives Weck knives Epinephrine-soaked sponges: 5 cc 1/1000 epinephrine per 1 L normal saline Electrocautery Dermatome Mesher Burn dressings Tumescent solution: 1 liter lactated Ringer’s or normal saline, 1 cc 1:1000 epinephrine, 30 cc 0.25% Marcaine (Figs. 4.1.5 and 4.1.6)
Anesthesia Concerns Airway management in the burn victim can be extremely challenging. Edema of the surrounding tissues can obscure normal structures and make standard endotracheal intubation impossible. For patients with extensive burns to the head and neck or large TBSA burns, we recommend early intubation before the onset of edema. Edema will obliterate
230
SECTION 4 Burns
FIG. 4.1.5 Typical dermatome setup with multiple guards allowing different widths of skin graft harvest.
normal tissue while removing all burned tissue.1,3 The surgeon will select the Watson or Weck knife based on the size, depth, and location of the burn and on the thickness of the skin in that anatomical area. Large, deep burns on the torso and upper and lower extremities are excised with the Watson knife. Smaller burns or wounds on the hands and feet are excised using the Weck knife. The depth of the excision can be adjusted by the guard on the Weck knife. There are three standard guards with depths of 0.08, 0.10, and 0.12 inches. The Watson knife has an adjustable depth that is controlled by the surgeon to allow for deeper or more superficial excisions as the situation warrants (Video 4.1.1). The knife is held at a 45-degree angle to the skin, and the eschar is incised. The blade angle is then decreased to ~30 degrees. The blade is moved back and forth like the bow on a string instrument with gentle pressure moving it forward to lift the eschar off of the wound. Once the initial layer of the eschar is removed in this fashion, the wound bed is assessed for viability. A pearly-white dermis, light-yellow fat with punctate bleeding, and patent blood vessels indicate adequate excision. Ecchymosis within the tissue, brown discoloration of the fat, and lack of bleeding indicate that additional excision is required. The procedure should be performed repeatedly until the signs of a healthy wound bed described earlier are appreciated (Videos 4.1.2 and 4.1.3).4 Epinephrinesoaked sponges should be applied to the wound bed as soon as excision is complete. Large venous or arterial bleeding should be controlled with the electrocautery, sutures, or Hemaclips. Smaller dermal and punctate bleeding can usually be controlled with epinephrine-soaked sponges. Skin grafts can be harvested while the epinephrine solution is taking effect.
Skin Grafting
FIG. 4.1.6 Watson knives (left) and Weck knives (right) used for tangential excision of burn wounds.
normal landmarks, and a surgical airway may become necessary. Once scarring has developed, oral opening and neck extension may be limited, making intubation difficult. Fiber-optic intubation may be necessary in these situations. Burn surgery is often associated with large and rapid blood loss. The amount of blood loss will correlate with the size of the excised area, the presence of infection, and any underlying coagulopathies. Large-bore IV access and ongoing assessment of blood loss are critical to maintaining euvolemia and avoiding shock. Burn patients have difficulty with thermoregulation due to their lack of skin. This becomes pronounced in the operating room when the patient is stripped of dressings, and multiple sites are exposed for excision and donor site harvest. A warming protocol should be developed before surgery so it can be implemented when the patient arrives in the operating room. Warming the room and all fluids, placing a warming blanket under and over the patient during surgery, and wrapping the patient’s head in heated blankets are all techniques used to maintain normothermia during surgery.
SURGERY Tangential excision is the process by which the burn eschar is removed. Janzekovic described this procedure in 1970 with the goal of preserving
An autograft skin graft is the patient’s own skin, composed of the epidermis and a portion of the dermis. Enough dermis is left in the native wound bed for the wound to heal by re-epithelialization. An electric- or air-powered dermatome can be used to harvest the skin graft. The thickness of the graft is determined by setting the thickness of the opening on the blade of the dermatome (Video 4.1.4). Mineral oil is applied to the skin to allow the dermatome to slide smoothly over the skin surface. The dermatome is angled at 60 degrees to the patient’s skin, turned on, and then placed onto the skin (Video 4.1.5). With gentle pressure, the device is slid along the skin at an approximately 30- to 45-degree angle. The surgeon can visualize the graft coming up over the blade of the device, so he/she knows that the machine has adequately engaged the skin. Grafts can be harvested from any area of unburned skin. Large, flat areas yield the best grafts, so the thigh is the first choice for a donor site. Areas with bony prominences can be made smooth by the subcutaneous injection of tumescent solution. Epinephrine and local anesthetics are added to assist with hemostasis and postoperative pain control. The fluid is injected into the subcutaneous tissue until the skin becomes smooth. Grafts can then be harvested in a standard fashion. The skin grafts may then be meshed to allow for coverage of larger surface areas. Grafts should be placed in moist saline sponges until they are ready to be used. Once the wound bed is adequately excised and hemostasis has been achieved, the grafts are applied dermal side down and secured in place using surgical staples.
Escharotomies In cases of severe, deep partial- or full-thickness burns, escharotomies may be necessary. Escharotomy is defined as the surgical incision through the eschar into the subcutaneous tissues to allow the extremity to continue to swell without compressing the underlying blood vessels. Circumferential deep second- and third-degree burns of the extremities can act as a tourniquet and impede blood flow to the distal extremity. Deep burns to the chest and back can cause difficulty with
CHAPTER 4.1 Acute Burn Management
231
FIG. 4.1.7 An example of an upper-arm escharotomy.
FIG. 4.1.9 An example of a chest escharotomy.
FIG. 4.1.8 An example of a leg escharotomy.
chest wall excursion and thereby inhibit ventilation. Escharotomies are performed to release the compression and allow for distal blood flow and/or chest wall movement. Escharotomies are performed using a knife or electrocautery. The area is prepped in the standard fashion. The eschar is then incised down to the subcutaneous fat. Incisions on the upper extremities are made along the radial and ulnar aspects of the arm. In the fingers, midlateral escharotomies are made on the non-contact sides. On the leg, the incisions are made medially and laterally 180 degrees apart. Chest escharotomies are performed in the anterior axillary lines and along the subcostal margin. Usually the skin edges “pop” open due to the underlying pressure in the tissues, indicating adequate release. When complete, the wound edges are usually separated by at least 1 cm. The wound is then dressed in the standard fashion (Figs. 4.1.7–4.1.9).
POST-OPERATIVE CARE Dressings: Skin grafts are dressed with non-adherent gauze and moist antimicrobial dressings. For small, clean wounds, dressings are left in place for 5 days and then wound care reinstituted. For large, contaminated wounds, the dressings are changed on the third postoperative day. Early wound infections can be addressed, and grafts salvaged with this approach. Splinting: Splints are used when skin grafts are placed across joints or on areas of movement. Splints are most commonly used on the extremities, neck, and axillae. The splints prevent movement across joints so that there is no shearing of the grafts during the early
healing period. On post-operative day 5, range-of-motion exercises are begun, and splints are worn only at nighttime to prevent contracture. Therapy: Range-of-motion exercises are begun on post-operative day 5 or sooner if the grafts are completely adherent. Patients with grafts on their legs or feet may begin ambulation if they are able on postoperative day 5. Exercises progress from passive to active range of motion and then to strengthening as tolerated. Early contractures are identified and treated aggressively with therapy. Return to activity: Patients are encouraged to return to their normal activities as soon as possible. Patients with lower-extremity burns often have prolonged edema and pain with standing for long periods of time. Return to work and regular activities is therefore delayed.
MANAGEMENT OF COMPLICATIONS Graft loss: Loss of a skin graft results from infection, inadequate wound debridement, hematoma, seroma, shear, or pressure. Prevention of these factors will help ensure good graft take. Partial graft loss can usually be managed conservatively with wound care, and the area of loss will heal by secondary intention (Fig. 4.1.10). For large graft loss or complete graft loss, a period of wound care is instituted to ensure that the wound bed is adequate. Regrafting is usually performed when conditions are optimized to ensure good graft take. Infection: Bacterial contamination or infection of the wound bed can usually be managed topically with antimicrobial dressings. If a skin graft failed to take because of infection, systemic antibiotics should be considered before a second skin graft procedure. Inadvertent injuries: Although they set the depth of excision, the Weck and Watson knives can cut deeper and injure underlying structures. The surgeon must keep the blade angled to the skin and not press too deeply into the tissues. If the blade is held at a 90-degree angle
232
SECTION 4 Burns KEY PRINCIPLES • Burns are described as first, second, third, and fourth degree based on the depth of injury. • Third-degree burns require surgery to heal. Superficial second-degree burns should not need surgery. Deep second-degree burns may require surgery. • The burn wound should be excised following the principle of tangential excision. Adequate excision and post-operative immobilization are critical to ensure skin graft survival. • Skin grafts should be dressed with antimicrobial dressings until they have healed. • Range of motion should be instituted as soon as the grafts are well adhered to prevent contracture. This usually occurs by post-operative day 5.
FIG. 4.1.10 An example of partial skin graft loss.
to the skin, it will slice directly into the tissues and can easily injure underlying structures. When using the tumescent technique, the surgeon must ensure that the fluid is injected into the subcutaneous space and not the subfascial space. Inadvertent injection into the muscle compartment may result in compartment syndrome.
KEY REFERENCES 1. Baxter CR. Fluid volume and electrolyte changes of the early postburn period. Clin Plast Surg. 1974;1(4):693–703. 2. Gray DT, Pine RW, Harnar TJ, et al. Early surgical excision versus conventional therapy in patients with 20 to 40 percent burns. A comparative study. Am J Surg. 1982;144(1):76–80. 3. Janzekovic Z. A new concept in the early excision and immediate grafting of burns. J Trauma. 1970;10(12):1103–1108. 4. Mosier MJ, Gibran NS. Surgical excision of the burn wound. Clin Plast Surg. 2009;36(4):617–625.