Burns principles and treatment Flashcards
A 2-year-old child has the findings shown in the photograph above six days after sustaining a full-thickness burn injury to the left hand when the hand was immersed in boiling water. Silver sulfadiazine dressings have been applied since the time of injury. Which of the following is the most appropriate next step in management?
(A) Continued use of silver sulfadiazine dressings for three weeks
(B) Tangential excision and coverage with split-thickness skin grafts
(C) Tangential excision and coverage with full-thickness skin grafts
(D) Fascial excision and coverage with full-thickness skin grafts
(E) Coverage with cryopreserved acellular dermal homograft and epidermal grafts
The correct response is Option B.
In this 2-year-old child who has a full-thickness burn, the most appropriate management is tangential excision to a level at which punctate bleeding occurs, followed by split-thickness skin grafting. The depth of the burn can be determined by serial examination; in this case, after six days, the wound is not vascularized and has not become epithelized. Because burns that have not healed 21 days after initial injury are associated with a significant risk for hypertrophic scarring and contracture, this child’s burn should be excised tangentially to the level of punctate bleeding. In addition, early skin grafting decreases the risk for scarring and permanent stiffness in patients with burns of the hand and increases the rehabilitation potential.
As implied above, continued application of silver sulfadiazine dressings is not appropriate in this patient. Any available full-thickness skin for grafting would most likely not be sufficient for coverage of this full-thickness burn involving most of the hand and forearm; a full-thickness graft is recommended instead for smaller areas that will contract only minimally. Although acellular dermal homograft has been shown to be beneficial in larger burns, its effects are limited in patients with burns limited to the hand who have other donor sites available.
A 57-year-old man develops exposure keratitis, corneal ulceration, and bilateral upper and lower eyelid ectropions 2 months after sustaining burns to the head and neck during a gas grill explosion. A photograph is shown. A tracheostomy was performed at the time of the accident for inhalation injury. Which of the following is the most definitive treatment modality for this patient’s condition?
A ) Adhesion tarsorrhaphy
B ) Bilateral tarsoconjunctival flaps
C ) Frost sutures
D ) Lateral tarsal strip canthoplasty
E ) Staged upper and lower ectropion releases with skin grafts
The correct response is Option E.
The patient described requires definitive treatment of the burn ectropions, which involves release of the ectropion and resurfacing of the orbicularis muscle with high-quality skin that will resist contraction. Although full-thickness skin grafts will have less of a tendency to contract than
split-thickness skin grafts, the shoulder and supraclavicular fossa are superior to the groin as donor sites in terms of texture and color match. Photographs are shown.
Tarsorrhaphy alone will provide temporary coverage of the cornea but neither addresses the underlying pathophysiology nor provides definitive correction of the ectropion. Simultaneous correction of all four eyelids does not permit adequate release of the ectropions, which must be overcorrected before grafting.
Although Frost sutures, tarsoconjunctival flaps, and lateral tarsal strip canthoplasties will provide temporary corneal protection, these procedures do not address the underlying problem, which is contracture of eyelid, forehead, and cheek skin, secondary to burn injury.
A 10-year-old girl who sustained an electrical burn to the right upper extremity 10 days ago has undergone multiple debridements of the distal volar forearm since that time. The residual volar forearm wound is clean and measures 4 _ 8 cm. Full-thickness skin loss is noted, as well as segmental loss of the flexor carpi ulnaris tendon. The ulnar nerve is exposed but appears in continuity. The patient has sensory loss in the ulnar nerve distribution and no ulnar intrinsic hand function. Which of the following is the most appropriate management?
(A) Daily whirlpool therapy and dressing changes
(B) Full-thickness skin grafting
(C) Resection of the exposed ulnar nerve and sural nerve grafting
(D) Flap coverage
(E) Tendon transfers and flap coverage of the wound
The correct response is Option D.
This child’s wound requires flap coverage. Vascularized tissue in the form of local or distant flaps is recommended for coverage of exposed vital structures such as nerves, blood vessels, tendons, and bone. Therefore, wound care regimens alone and skin grafting are inadequate treatment options.
Early repair or grafting of the ulnar nerve is not indicated due to the inability to predict the amount of recovery at this early stage. Children also heal significantly better than adults, particularly in cases of nerve injury. For the same reason, tendon transfer is not indicated at this early juncture. However, appropriate splinting and therapy should be used while awaiting recovery of the nerve to prevent the claw deformity associated with low ulnar nerve palsy.
True electrical burns are completely different from thermal burns. Entrance and exit wounds can usually be identified and can be widely separated. The damage to underlying structures such as musculature and neurovascular structures typically far exceeds the visible cutaneous injury. Most patients will require decompression with fasciotomies and multiple debridements.
A 45-year-old man is brought to the burn unit after sustaining injuries during a house fire. Heart rate is 112 bpm, respiratory rate is 10/min, blood pressure is 113/63 mmHg, and oxygen saturation on room air is 98%. Physical examination shows charring of the face, singed eyebrows, and coarse breath sounds on inspiration. Which of the following is the most appropriate first step in management?
A) Application of a face mask at 40% oxygen
B) Bilevel positive airway pressure
C) Hyperbaric oxygen therapy
D) Intubation with 100% oxygen delivery
E) Oxygenation with 6 L nasal cannula
The correct response is Option D.
The patient is at risk for carbon monoxide (CO) toxicity and impending airway collapse. This patient was involved in a house fire and he has signs of lung injury. He should be intubated for airway protection because of his high potential for respiratory collapse. The patient’s normal-appearing oxygen saturation is a result of CO poisoning leading to carboxyhemoglobin being mistaken for oxyhemoglobin. Getting a carboxyhemoglobin level will assist in the diagnosis. The treatment for CO toxicity is 100% inhaled oxygen, which will lead to dissociation of the CO molecule from hemoglobin.
Hyperbaric oxygen treatment has been proposed as a potential treatment for CO toxicity, but the data are controversial, and treatment may be inappropriate in a burn patient undergoing resuscitation.
Even though the patient has an oxygen saturation of 98%, it is falsely elevated in CO poisoning.
This patient has stridor and is at risk for airway edema and should be immediately intubated.
Bilevel positive airway pressure does not protect the airway.
A 19-year-old man is undergoing open reduction and internal fixation of multiple facial fractures when the nasal endotracheal tube is accidentally disconnected from the breathing circuit. The surgeon, who is performing electrocauterization, witnesses an unexpected flash in the operative field. The surgeon immediately stops the procedure and alerts the anesthesiologist. Smoke and a burning odor coming out of the patient’s airway are noted. Which of the following is the most appropriate next step in management?
A) Decrease the flow of airway gases by half
B) Immediately remove the endotracheal tube
C) Pack the oral and nasal cavities with sponges
D) Perform emergency bronchoscopy
E) Reconnect the endotracheal tube
The correct response is Option B.
This surgical team is confronted with a fire in the operating room, involving the airway. The most appropriate next step is immediate removal of the endotracheal tube, without waiting.
The incidence of operating room fires in the United States is estimated to be around 600 cases per year. Fire requires the presence of three components: fuel, an oxidizer, and an ignition source. Common fuels in the operating room include alcohol-containing prepping agents, drapes and bandages, gowns and other personal protection equipment, petroleum jelly, etc. Ignition sources include the electrocauterization lasers, fiberoptic light sources, and defibrillators. The two most common oxidizing agents in the operating room are oxygen and nitrous oxide.
Early warning signs of fire include unexpected flash, flame, smoke or heat, unusual sounds (e.g., a “pop,” “snap,” or “foomp”) or odors, unexpected movement of drapes, discoloration of drapes or breathing circuit, and unexpected patient movement or complaint. The surgical procedure should be immediately halted so the team can evaluate whether fire is indeed present.
In cases of airway fire, the ASA practice advisory recommends immediate (without waiting) removal of the tracheal tube, interruption of flow of all airway gases, removal of all sponges or any other flammable materials from airway, and pouring of saline into the airway. Once the fire is extinguished, subsequent steps consist of re-establishing ventilation, avoiding oxidizer-enriched atmosphere if clinically appropriate, examining of the endotracheal tube for possible fragments left behind in the patient’s airway, and considering bronchoscopy.
A 22-lb (10-kg), 18-month-old male infant is brought to the emergency department because of second- and third-degree thermal burns on the torso and lower extremities. Examination shows burns on 30% of the total body surface area. Administration of which of the following solutions is most appropriate for initial resuscitation of this patient?
A) Hypertonic saline
B) Normal saline
C) Normal saline with 5% dextrose
D) Ringer’s lactate
E) Ringer’s lactate with 5% dextrose
The correct response is Option E.
Fluid resuscitation is critical to combat the inflammatory response that occurs after a large burn and prevent the patient from going into shock. Burn injury leads to a combination of hypovolemic and distributive shock resulting from generalized microvascular injury and interstitial third spacing. The goal of fluid resuscitation is to ensure end-organ perfusion while avoiding intracompartmental edema. Ringer’s lactate solution is a relatively isotonic solution that has been advocated as the key component for almost all resuscitation strategies during the first 24 to 48 hours. It is preferable to isotonic normal saline in large-volume resuscitation because its lower sodium concentration (130 mEq/L vs 154 mEq/L) and higher pH concentration (6.5 vs 5.0) are closer to physiologic levels. Ringer’s lactate also has the potential added benefit of the buffering effect of metabolized lactate on the associated metabolic acidosis.
Toddlers in particular are susceptible to inadequate fluid resuscitation and should be monitored closely to ensure adequate urine output of at least 1 mg/kg/hr. In children with burns greater than 15% total body surface area, weighing less than 20 kg and younger than 2 years of age, 5% dextrose should be added to the resuscitation fluid to prevent life-threatening hypoglycemia. These younger patients have lower hepatic glycogen reserves that can be quickly depleted after such significant injuries.
Hypertonic saline and colloid solutions have been advocated and successfully used by some in large-volume resuscitation, but their use still remains controversial and not universally accepted in initial resuscitation.
A 19-year-old man reports severe, worsening arm pain and finger swelling accompanied by distal numbness. He sustained a circumferential burn to the arm 12 hours ago. The area of burned skin itself is noted to be leathery and insensate. Examination demonstrates loss of distal pulses. Which of the following is the most appropriate next step?
A) Angiography
B) CT scanning
C) Duplex ultrasonography
D) Escharotomy
E) Fasciotomy
The correct response is Option D.
The most appropriate next step is escharotomy. The patient exhibits signs of vascular compromise due to tight restrictive burn eschar arising from a circumferential full-thickness burn. Edema following a burn due to inflammation and fluid resuscitation can cause increased swelling of the tissues, and the presence of tight circumferential eschar can give rise to vascular compromise. Release of the burn eschar (escharotomy) is indicated to relieve pressure on the tissues and allow for restoration of blood flow.
Burns are classified into partial thickness and full thickness, and into different degrees based on the depth of injury. In the case of full-thickness (third-degree or fourth-degree) burns, the area of burned skin is insensate and may appear charred or leathery. Eschar formation in circumferential burns can lead to a tourniquet effect, with impaired circulation. In some cases, circumferential burns of the torso may even give rise to respiratory compromise or abdominal compartment syndrome.
Escharotomy differs from fasciotomy in that the incision is made more superficially, to open the thick burn eschar, and does not need to extend deep to the fascia.
Angiography would be useful in evaluating vasculature and blood flow, but would not be needed in this situation and would delay treatment.
CT scanning can provide detailed imaging, but it would not be indicated in this situation and would delay treatment.
Duplex ultrasonography can evaluate the presence of deep vein thrombosis, which could cause pain and swelling. However, in this case, the clinical scenario suggests that circulatory restriction is due to the circumferential burn scar.
Fasciotomy is recommended in the case of increased compartment pressures, which may also present with pain, paresthesia, and loss of pulses, although in this instance the presence of a circumferential burn would indicate escharotomy as the treatment.
Fasciotomy is advised if compartment pressure exceeds 30 mmHg, or if the difference between intracompartmental pressure and diastolic blood pressure is less than 30 mmHg.
In a patient with burns covering more than 30% of the total body surface area, which of the following parameters is most likely to increase in the first few hours of the pre-resuscitation phase?
A) Cardiac output
B) Peripheral blood flow
C) Plasma volume
D) Systemic vascular resistance
E) Urine output
The correct response is Option D.
Extensive burn injuries are characterized by the hemodynamic changes seen in hypovolemia, including decreased cardiac output, decreased peripheral blood flow, and decreased urine output. Decreased plasma volume is seen secondary to extravasation of plasma into the burn wound and surrounding tissues. Increased systemic vascular resistance is found in hypovolemia.
In a patient who sustained third-degree burns one hour ago, which of the following mechanisms associated with the initial inflammatory response is most likely to result in progressive tissue destruction?
(A) Downregulation of integrins
(B) Increased chemotaxis
(C) Inhibition of neutrophil degranulation
(D) Inhibition of tumor necrosis factor-alpha and interleukins 1 and 8
(E) Replacement of neutrophils with macrophages
The correct response is Option B.
During the first few hours after burn injury, multiple cytokines act to mediate a massive inflammatory response. Tumor necrosis factor-alpha (TNF-_) and interleukins 1 and 8 are released, resulting in increased chemotaxis of neutrophils into the wound. Upregulation of integrins also occurs following the release of TNF-_ and interleukins, and cell surface adherence receptors appear on neutrophils and endothelial cells. During this phase, neutrophils migrating into the wound adhere to the capillary endothelium and degranulate, resulting in the release of proteases and toxic oxygen-free radicals, leading to further tissue destruction. Macrophages gradually replace neutrophils over the first few days following injury and produce cytokines, which are critical for wound healing.
An 8-year-old girl presents with burns on 60% of the total body surface area. Physical examination shows second- and third-degree burns involving her face, neck, and torso. After initial resuscitation, wound care, burn debridement, and skin grafting are performed, rehabilitation protocol is initiated. Administration of which of the following agents is most appropriate for improving bone mineral content (BMC) in this patient?
A) Ascorbic acid
B) Glutamine
C) Insulin
D) Oxandrolone
E) Testosterone
The correct response is Option D.
A randomized clinical trial of safety and efficacy of 1-year oxandrolone administration to severely burned children (over 30% total body surface area burns) demonstrated significant benefits of this medication. Improvements were noted in height, bone mineral content (BMC), cardiac work, and muscle strength, and were statistically higher compared to the control group. Mechanism of action is not totally clear but increase in insulin-like growth factor-1 secretion during the first year after burn injury, and, in combination with exercise, considerable increase in lean body mass and muscle strength has been demonstrated. The maximal effect of oxandrolone was found in children aged 7 to 18 years. No deleterious side effects were attributed to long-term administration.
Oxandrolone, a synthetic oral nonaromatizable testosterone derivative, has only 5% of the virilizing activity and low hepatotoxicity when compared with testosterone administration. Oxandrolone reaches peak serum concentrations within 1 hour and is excreted through the urine. Oxandrolone binds to androgen receptors in the skeletal muscle to initiate protein synthesis and anabolism. Because oxandrolone cannot be aromatized to estrogen, the likelihood of estrogen-dependent bone-age advancement is reduced, making oxandrolone a safe therapeutic approach for growing children.
Testosterone is not currently approved for treatment of burned children due to increased risks of virilization in female patients and aromatization effects among other health risks.
Glutamine and ascorbic acid supplementation can aid in burn recovery; however, it has not shown to have similar effects on bone density as oxandrolone. Several studies support the use of enteral glutamine supplements in the adult burn population. Research has also shown that glutamine supplementation is favorable as it has the potential to decrease length of stay and associated costs through improving wound healing and decreasing rates of infection and mortality.
Antioxidant therapies including: ascorbic acid; glutathione; N-acetyl-L-cysteine; vitamins A, C, and E; alone or in combination have been previously shown to protect microvascular circulation, mitigate changes in cellular energetics, decrease tissue lipid peroxidation, and decrease the volume of fluid required for resuscitation.
Insulin is used to treat hyperglycemia and primarily used in diabetic patients. It may have limited use in burn care patients but has not shown to increase bone mineral density.
A 19-year-old woman presents with a 2 × 3-cm burn to the left dorsal thumb sustained from brief exposure to hot bacon grease. During the next 24 hours, the burned area becomes erythematous and several blisters containing clear fluid have formed and then ruptured. Examination shows no erythema extending proximally. A photograph is shown. Which of the following is the most appropriate next step in management?
A) Dry dressing
B) Hydrogen peroxide soaks
C) Leave open to air
D) Topical antibiotic ointment
The correct response is Option D.
Based on the information provided, this is likely a superficial partial-thickness burn. It is not deep enough or large enough to warrant transfer to a burn center. Local wound care should lead to full resolution, with appropriate follow-up to detect delays in healing. Partial-thickness wounds like this will heal fastest when a moist environment is maintained. Antibiotic ointment or other neutral moisturizing agents (e.g., petrolatum ointment) are appropriate for local wound care. Leaving the wound open to air or covering with a dry dressing will delay healing. Hydrogen peroxide is appropriate for cleansing dirty or infected wounds, but it is not necessary in the scenario presented. Furthermore, sustained use of hydrogen peroxide may delay healing in clean wounds.
A 30-year-old man sustains burns over 42% of the total body surface area and is resuscitated using the Parkland (Baxter) burn formula. Five percent albumin is added to the resuscitation fluid 24 hours after the injury to achieve which of the following?
(A) Maintenance of intravascular volume
(B) Normalization of intravascular pH
(C) Nutritional support
(D) Provision of coagulation cofactors
The correct response is Option A.
Acute burn resuscitation using the Parkland (Baxter) formula is based on the patient’s physiologic response to injury. Burns cause a leak in the capillary endothelium, which results in excessive protein loss. By 24 hours after the burn injury, the capillary leak is largely resolved. At that time, 5% albumin is added to the resuscitation fluid to help maintain intravascular volume.
A 30-year-old woman who is morbidly obese is admitted to the burn unit with partial-thickness burns on 40% of the total body surface area involving the trunk and lower extremity. Maintenance of which of the following is the most appropriate measure to guide proper fluid management of the patient?
A ) Arterial systolic pressure greater than 90 mmHg
B ) Cardiac output greater than 5 L/min
C ) Mean arterial pressure greater than 55 mmHg
D ) Pulse rate less than 120 bpm
E ) Urinary output of 0.5 mL/kg/h
The correct response is Option E.
Routine vital signs, such as blood pressure and heart rate, can be very difficult to interpret in patients with large burns. Catecholamine release during the hours after the burn can support cardiac output despite the extensive intravascular depletion that exists. The formation of edema in the extremities can limit the usefulness of noninvasive blood pressure measurements. Evaluation of arterial line pressures is subject to error from peripheral vasospasm from the high-catecholamine state. Tachycardia, normally a clue to hypovolemia, can be secondary to pain and is also almost universally present from the adrenergic state. Moreover, placement of a central line to measure the cardiac output in a morbidly obese patient may pose risks and should be avoided unless the burns involve the upper part of the body, which will lead to edema in the later stages of resuscitation. Blood pressure is not an accurate measure of tissue perfusion.
Hourly urine output is a well-established parameter for guiding fluid management. The rate of fluid administration should be titrated to a urine output of 0.5 mL/kg/h or approximately 30 to 50 mL/h in most adults and older children (> 50 kg [110 lb]). The urge to maintain urine output at rates greater than 30 to 50 mL/h should be avoided. Fluid overload in the critical hours of early burn management leads to unnecessary edema and pulmonary dysfunction. It can necessitate morbid escharotomies and extend the time required for ventilator support. Several complicating factors exist with monitoring urine output as a guide for volume status and end-organ perfusion. The presence of glycosuria can result in an osmotic diuresis and lead to artificially elevated urine output values. Performing a urinalysis at some point during the first 8 hours is prudent, especially for patients with larger burns, to screen for this potentially serious overestimation of the intravascular volume.
A 32-year-old man is brought to the emergency department with a full-thickness thermal burn injury to the left ear. Which of the following therapeutic agents allows for the most effective preservation of involved cartilage?
A) Acetic acid
B) Honey
C) Mafenide acetate
D) Nanocrystalline silver dressings
E) Silver sulfadiazine
Mafenide acetate effectively penetrates burn eschar as well as cartilage and decreases the risk of suppurative chondritis in the setting of burns of the auricle. Twice-daily application is recommended. Care must be taken to monitor for metabolic acidosis, as mafenide acetate is metabolized to sulfamoylbenzoic acid, a carbonic anhydrase inhibitor. Silver sulfadiazine, nanocrystalline silver dressings, honey, and acetic acid have not demonstrated similar efficacy in preventing burn-associated chondritis.
A 24-year-old man has a mentosternal contracture (shown above) one year after sustaining burns over 90% of the total body surface area. Which of the following reconstructive interventions is the most appropriate management of the contracture?
(A) Scar release and coverage with a dorsal scapular island flap
(B) Scar release and coverage with a free scapular flap
(C) Scar release and skin graft coverage with a thin split-thickness skin graft harvested from the scalp
(D) Scar release and use of the dermal regeneration template (Integra)
The correct response is Option D.
A mentosternal contracture usually requires a wide scar release and extensive tissue coverage. However, this patient who has burns over nearly the total body surface area has limited donor sites. Therefore, the dermal regeneration template should be used with thin split-thickness grafting. This reconstructive intervention provides an acceptably low rate of long-term recurrence of contracture and it uses available donor sites.
Scar release and coverage with a thin split-thickness skin graft have an unacceptable rate of recurrence of contracture. Scar release and coverage with a free scapular flap or dorsal scapular island flap are ideal options for reconstruction. However, unburned scapular skin is not likely to be available in a patient with burns over 90% of the total body surface area.
Which of the following is a physiologic manifestation of shock following acute burn injury?
(A) Decreased cardiac output
(B) Decreased systemic vascular resistance
(C) Increased peripheral blood flow
(D) Increased plasma volume
(E) Increased urine output
The correct response is Option A.
Patients with acute burn shock exhibit hemodynamic changes similar to those seen with hypovolemic shock. Management should focus on volume resuscitation and maintenance of tissue perfusion.
Following burn injury, cardiac output is decreased to 40% to 60% of normal as a result of decreased plasma volume and increased systemic vascular resistance. The release of myocardial depressants further diminishes cardiac output. In addition, angiotensin II, catecholamines, neuropeptide Y, and vasopressin all act on arterial smooth muscle to cause vasoconstriction.
Decreased plasma volume and capillary pressure occur as a result of factors released from both injured and uninjured tissue and excessive fluid shifting that occurs within the first hour after injury. Although the total body water level remains constant, there is an increase in cell water content of 70% to 80%. Volume resuscitation is required to maintain tissue perfusion; unfortunately, this will also exacerbate burn wound edema.
Decreased urine output is caused by inadequate fluid resuscitation and occurs as a response to decreased tissue perfusion and increased systemic vascular resistance. Aggressive volume replacement is required during the first 24 to 48 hours after injury to restore intravascular fluid.
An otherwise healthy, 32-year-old woman with a history of burns on 20% of the total body surface area of the left upper extremity and chest, returns 1 year after her injury for evaluation of a nonhealing wound over the dorsal elbow and limited range of motion at the joint. X-ray studies show soft-tissue lamellar calcification. Which of the following is the most likely diagnosis?
A) Chronic osteomyelitis
B) Heterotopic ossification
C) Hypertrophic scar
D) Marjolin ulcer
E) Retained foreign body
The correct response is Option B.
The most likely diagnosis is heterotopic ossification (HO). An important complication of massive burn injury (greater than 20 % BSA) is heterotopic ossification, with the elbow region being the most common site of occurrence. This may result in wound issues, stiffness, and nerve injury. HO can occur in 0.2 to 4 % of cases. Prevention of this condition includes radiation therapy and nonsteroidal anti-inflammatory drugs. Surgical excision is the procedure of choice for restoration of range of motion.
Hypertrophic scars present as raised thickened scars following burn injury but do not show ossification within the scar. The most common scenario for development of a Marjolin’s ulcer is malignant degeneration of a previous scar, usually squamous cell carcinoma. The latency period for development of this type of malignancy is usually 10 years after the original injury at the earliest. Chronic osteomyelitis would show radiolucency and changes within the bone not the soft tissue. The x-ray finding is not consistent with a retained foreign body.
An unconscious 25-year-old man is brought to the emergency department after being electrocuted while working near high-voltage power lines. The patient is resuscitated. Examination shows a 4 × 3-cm burn on the skin over the left antecubital fossa and significant swelling of the forearm. Which of the following is the most appropriate next step in management?
A ) Dressing of the affected area and observation in the burn unit
B ) Excision and coverage with a local flap
C ) Excision and coverage with a split-thickness skin graft
D ) Fasciotomy of the forearm
E ) Splinting of the hand in the intrinsic plus position
The correct response is Option D.
In high-voltage injuries, the electrical current often travels deep into the skin, causing internal damage that may not be readily visible. The current causes tissue damage at the entry point in the skin and along its path through the muscle, nerves, and bone. As electrical current is conducted through the body, heat is generated in direct proportion to the tissue resistance. Because bone has a high resistance, heat is generated rapidly in this area, resulting in deep tissue injury. Compartment syndrome can develop in a patient with an electrical injury because of the deep tissue injury and subsequent subfascial edema. Immediate treatment is aimed at resuscitation of the patient, followed by salvage of the affected limb. The key to the acute management of electrical injuries to the upper extremity is to have a high index of suspicion for potential damage to deeper tissues, even at a distance from the point of contact. The optimal management of electrical injuries to the upper extremity includes initial exploration, decompression (fasciotomy), and aggressive repeated debridement, followed by reconstruction. Fasciotomy serves a dual role as both a therapeutic and diagnostic tool in the treatment of electrical injuries.
A 42-year-old lineman is evaluated after sustaining a high-voltage electrical injury while working on a transformer. Physical examination shows entrance wounds on the volar aspect of the right distal forearm. He reports numbness and tingling of the little finger and weakness of the grip of the right hand. Which of the following is the most appropriate next step in management?
A) Elevation of the forearm and observation
B) Escharotomy and carpal tunnel release
C) Escharotomy and excision of the burned tissue
D) Fasciotomy of the forearm
E) Fasciotomy and release of Guyon canal
The correct response is Option E.
This lineman has developed compartment syndrome involving at least the ulnar nerve and has signs of motor and sensory impairment. Escharotomy is not an adequate release in electrical injuries, which often involve deeper structures, such as the pronator quadratus. Therefore, fasciotomy is required. While a carpal tunnel release should be performed in this case, release of Guyon’s canal and decompression of the ulnar nerve in the forearm, wrist, and hand must be performed.
A 33-year-old man who weighs 80 kg is brought to the emergency department eight hours after sustaining deep partial-thickness burns involving 25% total body surface area (TBSA) and full-thickness burns involving 15% TBSA. According to the Parkland formula, how many milliliters (mL) of crystalloid should be administered for initial fluid resuscitation over the next eight hours?
(A) 3200
(B) 6400
(C) 9600
(D) 12,800
(E) 16,000
The correct response is Option C.
In a patient who has a burn injury that covers more than 20% of the total body surface area (TBSA), acute fluid resuscitation should be performed with administration of crystalloid during the initial 24 hours after injury. The Parkland formula is used to estimate the amount of fluid required. According to this formula, lactated Ringer’s solution 4 mL/kg/% TBSA burned should be administered during the first 24 hours. A total of 50% of the solution should be administered during the first eight-hour period and the remaining 50% over the next 16 hours.
An 80-kg patient who has burns involving 40% TBSA will require 12,800 mL of fluid during the first 24 hours: 6400 mL during the first eight hours and the remaining 3200 mL in both the second and third eight-hour periods. Because he received no fluid during the first eight hours immediately following injury, 9600 mL of crystalloid should be administered over the next eight hours in order to adequately resuscitate the patient.
A 62-year-old woman comes to the office for consultation regarding problems with her left eye (shown) 6 months after sustaining a 25% total body surface area (TBSA) burn that involved the face and neck. She reports that the upper eyelid turns outward, that she cannot close the eye completely, and that the eye tears excessively. These symptoms have persisted despite skin grafting several months ago by another surgeon. Physical examination confirms ectropion of the upper eyelid, lagophthalmos, and epiphora of the left eye. Which of the following is the most appropriate next step in management?
A ) Insertion of a gold weight
B ) Paramedian forehead flap
C ) Permanent lateral tarsorrhaphy
D ) Reverse tarsoconjunctival flap
E ) Skin grafting
The correct response is Option E.
Patients with significant burns to the periocular area commonly have ectropion with corneal exposure, even after primary attempts at skin grafting. It is clear that damaged contracted skin has left this patient’s skin short, thereby preventing complete closure of the eyelid. The optimal method of eyelid reconstruction in this patient is a release of the burn scar contracture with placement of nonburned, thin, pliable skin to the area in order to bring tissue to the area, thereby correcting the underlying problem. Although multiple options for reconstruction exist, the most reasonable would involve regrafting the upper eyelid. While the literature’s dogma has been to graft the upper eyelid with split grafts and the lower eyelid with full-thickness grafts, this has not been definitely proven one way or the other by the available data. However, repeat grafting (either with thin or full-thickness grafts) to correct this problem has been used successfully to achieve good outcomes.
A gold weight is used for the paralytic eyelid after facial nerve injury.
A permanent lateral tarsorrhaphy can be performed but will narrow the ocular aperture and can be irritating to the patient.
Forehead flaps have been described to reconstruct eyelids, especially large full-thickness defects. Their biggest downside, however, is the thickness of the tissue transferred, which certainly does not reapproximate the thickness of the native upper eyelid. It also involves a two-stage procedure. The patient described has suffered burns to her face and neck, including the forehead, which renders this method of reconstruction suboptimal.
A reverse tarsoconjunctival flap can be used to reconstruct upper eyelids; however, it is generally used when the lower eyelid is not involved in the injury. It also has the disadvantages of requiring two operations, occluding the visual axis, and can only be performed with a minimum of lower eyelid tarsus, as only 2 to 3 mm is available for transfer. This patient’s upper eyelid requires more tissue than what this technique can deliver.
A 27-year-old man is evaluated in the intensive care unit for polytrauma 12 hours after sustaining burns on 10% of the total body surface area over the bilateral lower extremities during an industrial accident. The patient is sedated, intubated, and is being resuscitated appropriately. Examination shows the wounds are waxy and thick, but not circumferential. He has a nondisplaced fracture of the left tibia; physical examination of the left lower extremity shows that the toes are cool and cyanotic, which is markedly different from the right foot. Left lower extremity pulses are intact, but the left calf is much larger and firmer. Which of the following is the most appropriate next step in management of the left lower extremity?
A) Ankle brachial index
B) CT angiography
C) Elevation
D) Escharatomy
E) Fasciotomy
The correct response is Option E.
Compartment syndrome consists of increased pressure within enclosed compartments, resulting in decreased blood flow. For extremities, the concern is for muscle ischemia, as decreased perfusion is unable to supply the metabolic demand. The five P’s of compartment syndrome (pain, pallor, paresthesia, pulselessness, and paralysis) are a good guideline, but are not entirely helpful in this case. As the patient is intubated, pain, paresthesia, and paralysis are unable to be assessed. Skin pallor is confused by the burn eschar, and pulselessness is an extremely late finding. Compartment syndrome needs to be diagnosed early for intervention to be effective. High clinical suspicion is mandatory for this patient because of his clinical condition and trauma. Although measurement of intracompartmental pressures can be done, his ongoing fluid resuscitation and current clinical examination would prompt an emergent surgical intervention.
Elevation is not adequate treatment for compartment syndrome.
Escharotomy would be inadequate as all four fascial compartments will need to be released. Although a circumferential eschar can cause compartment syndrome, this patient does not have circumferential eschar and has a tibial fracture, which points to requiring fascial release.
CT angiography and ankle brachial index are good evaluations of flow and perfusion; however, they are not appropriate in the time sequence of this patient.
A 30-year-old man is brought to the emergency department after sustaining second-degree burns of the trunk involving 10% total body surface area (TBSA). The burns are cleansed, and several blisters are debrided. In order to provide antimicrobial activity, which of the following dressings should be applied to the wounds?
(A) Fibronectin-coated skin substitute (Transcyte)
(B) Porous collagen-glycosaminoglycan membrane (Integra)
(C) Silicone membrane-nylon fabric composite (Biobrane)
(D) Silver-coated wound dressing (Acticoat)
The correct response is Option D.
Treatment of partial-thickness burns can be accomplished through cleansing of the burn and application of either an antimicrobial or occlusive dressing. Most patients are treated with silver sulfadiazine (Silvadene); however, if a sulfa allergy is present, bacitracin, polymyxin/bacitracin (Polysporin), or mupirocin (Bactroban) can be used. Acticoat is a dressing material coated with a thin soluble layer of silver ion; it reportedly provides antimicrobial activity for as long as five days. The greatest advantage is a decrease in the number of dressing changes, with a subsequent decrease in pain, as well as decreased cost.
Biobrane and Transcyte are occlusive dressings that can be used for management of clean second-degree burns as long as they are applied within the first 24 hours. These dressings do not provide antimicrobial activity. Biobrane consists of a nylon fabric containing chemically bound collagen that is partially imbedded in a silicone film. As blood and serum clot within the nylon fabric, it adheres to the wound until epithelialization occurs, and then it sloughs. Transcyte consists of cultured human dermal fibroblasts on a semipermeable membrane bonded to nylon mesh. The mesh allows for growth of the dermal tissue, and the membrane forms a synthetic epidermis.
Integra is a bioengineered dermal substitute consisting of a bilayered membrane system. It is used for skin replacement after debridement of deep partial-thickness or full-thickness burns. The dermal replacement layer comes from bovine tendon cartilage, and the epidermal replacement is a synthetic silicone polymer that is removed following degradation of the dermal layer. A thin skin graft is then placed on the “neodermis.”
Topical silver sulfadiazine may produce which of the following sequelae?
(A) Carbonic anhydrase inhibition
(B) Granulocyte reduction
(C) Methemoglobinemia
(D) Staining of the skin on contact
The correct response is Option B.
Silver sulfadiazine (Silvadene) is a commonly used topical burn agent. It may result in granulocyte reduction (neutropenia and thrombocytopenia). Carbonic anhydrase inhibition may occur with mafenide acetate (Sulfamylon), resulting in metabolic acidosis. Silver nitrate is an excellent topical agent and has no gram-negative resistance; however, brown staining of skin and equipment is common and methemoglobinemia may rarely occur.
A 26-year-old lineman is brought to emergency department after accidentally grabbing a high-voltage power line. The most severe injury is seen at which of the following anatomical locations?
A) Chest wall
B) Neck
C) Shoulder
D) Upper arm
E) Wrist
The correct response is Option E.
Severity of injury is proportional to the cross-sectional area of tissue able to carry current. Thus, the most severe injuries are seen at the wrists and ankles, with decreasing severity proximally. The extremities are the most frequently injured body parts, with the upper extremity predominating.
Most high-voltage injuries occur in workers on the job, so the voltage is known. Temperature increase parallels changes in amperage with tissue temperature being a critical factor in the magnitude of tissue damage. Tissue resistance from lowest to highest is nerve, blood vessels, muscle, skin, tendon, fat, and bone. Deep tissue seems to retain heat so that periosseous tissues, especially between two bones, often sustain a more severe injury than more superficial tissue. The associated macro- and microscopic vascular injury seems to occur nearly immediately and is not reversible. Alternating current (AC) causes tetanic muscle contraction, which may either throw victims away from contact or draw them into continued contact with the electrical source, the latter being more common, given our propensity to grasp at objects and the greater strength in our forearm flexors relative to extensors. This effect is often described as the “no-let-go” phenomenon. Altered levels of consciousness are reported in about half of high-voltage injuries. The tissue injury in electrical burns seems to be a combination of thermal and nonthermal mechanisms. If enough heat is generated, the tissue heats to supraphysiologic temperatures causing denaturation of macromolecules, which is usually irreversible. Electroporation refers to the formation of aqueous pores in lipid bilayers exposed to a supraphysiologic electric field. The applied electric field alters the transmembrane potential, with muscle fibers and nerves being the most susceptible. Subsequent pore formation likely allows calcium influx into the cytoplasm, thereby triggering apoptosis and cell death. Electroporation can therefore induce cell necrosis in the absence of heating.
Transmembrane protein molecules contain polar amino acid residues that can change orientation in an electric field. This effect, known as electroconformational protein degradation, may be irreversible and form yet another mechanism of nonthermal injury.
A 54-year-old man is brought to the emergency department (ED) 3 hours after
sustaining superficial burns to the entire left upper extremity and deep partial-
thickness burns to the entire right upper extremity and half of the right lower
extremity during a house fire. He did not receive any resuscitation before arriving
at the ED. He appears otherwise healthy, and he weighs 176 lbs (80 kg).
According to the Parkland formula, which of the following is the starting rate of
fluid resuscitation in this patient?
A) 360 mL/hr
B) 540 mL/hr
C) 576 mL/hr
D) 624 mL/hr
E) 864 mL/hr
The correct response is Option C.
The Parkland formula is used to calculate the initial resuscitation rate in burn patients. The
formula is as follows: total fluid needed in 24 hours = (total body surface area) × (4 mL/kg) ×
(body weight in kg).
Only second- and third-degree (superficial partial, deep partial, and full-thickness) burns are
used to calculate total body surface area in this equation. The “rule of nines” is used to
calculate this with each total upper extremity accounting for 9%, each entire lower extremity
accounting for 18%, and each side of the torso (anterior and posterior) accounting for 18%.
This equation gives the total fluid requirements for the first 24 hours following the burn, and
half of this fluid should be given in the first 8 hours after the burn while the remaining is
given in the next 16 hours.
For this scenario, the patient will need 5760 mL in 24 hours ([9% for right upper + 9% for
right lower] × 4 mL/kg × 80 kg). Half of this fluid (2880 mL) should be given in the first 8
hours, and since the patient arrived 3 hours after the accident, the 2880 mL should be given
over the next 5 hours (2880 mL/5 hr = 576 mL/hr).
REFERENCES:
1. Kahn S, Schoemann, Lentz C. Burn resuscitation index: a simple method for calculating
fluid resuscitation in the burn patient. J Burn Care Res. 2010;31(4):616-623. doi:
10.1097/BCR.0b013e3181e4d6ee
2. Schaefer TJ, Nunez Lopez O. Burn resuscitation and management. In: StatPearls
[Internet]. StatPearls Publishing; 2022. Updated January 31, 2022. Available at:
https://www.ncbi.nlm.nih.gov/books/NBK430795/
A 25-year-old woman is brought to the emergency department after sustaining deep partial-thickness and full-thickness burns to the face, neck, chest, back, and bilateral upper extremities in a grease fire. The patient is intubated and resuscitated, and the wounds are managed surgically. Which of the following is the most appropriate position to splint the burned areas?
A) Elbow extended at 180 degrees
B) Hands in intrinsic minus position
C) Neck flexed at 45 degrees
D) Shoulder abducted at 60 degrees
E) Wrist flexed at 10 degrees
The correct response is Option A.
The most appropriate position to splint the different burned areas is neck in slight extension, shoulder fully abducted to about 90 degrees, elbow fully extended at 180 degrees, wrist in neutral or slightly extended, and hands in intrinsic plus position or position of function. This is done to prevent contractures that would pull these joints into positions that would lead to functional deficits.
A 26-year-old lineman is brought to emergency department after accidentally grabbing a high-voltage power line. The most severe injury is seen at which of the following anatomical locations?
A) Chest wall
B) Neck
C) Shoulder
D) Upper Arm
E) Wrist
Correct answer is option E.
Severity of injury is proportional to the cross-sectional area of tissue able to carry current. Thus, the most severe injuries are seen at the wrists and ankles, with decreasing severity proximally. The extremities are the most frequently injured body parts, with the upper extremity predominating. Most high-voltage injuries occur in workers on the job, so the voltage is known. Temperature increase parallels changes in amperage with tissue temperature being a critical factor in the magnitude of tissue damage. Tissue resistance from lowest to highest is nerve, blood vessels, muscle, skin, tendon, fat, and bone. Deep tissue seems to retain heat so that periosseous tissues, especially between two bones, often sustain a more severe injury than more superficial tissue. The associated macro- and microscopic vascular injury seems to occur nearly immediately and is not reversible. Alternating current (AC) causes tetanic muscle contraction, which may either throw victims away from contact or draw them into continued contact with the electrical source, the latter being more common, given our propensity to grasp at objects and the greater strength in our forearm flexors relative to extensors. This effect is often described as the “no-let-go” phenomenon. Altered levels of consciousness are reported in about half of high-voltage injuries. The tissue injury in electrical burns seems to be a combination of thermal and nonthermal mechanisms. If enough heat is generated, the tissue heats to supraphysiologic temperatures causing denaturation of macromolecules, which is usually irreversible. Electroporation refers to the formation of aqueous pores in lipid bilayers exposed to a supraphysiologic electric field. The applied electric field alters the transmembrane potential, with muscle fibers and nerves being the most susceptible. Subsequent pore formation likely allows calcium influx into the cytoplasm, thereby triggering apoptosis and cell death. Electroporation can therefore induce cell necrosis in the absence of heating. Transmembrane protein molecules contain polar amino acid residues that can change orientation in an electric field. This effect, known as electroconformational protein degradation, may be irreversible and form yet another mechanism of nonthermal injury.
A 38-year-old man sustained frostbite of the right hand four days ago. Examination shows necrosis distal to the metacarpophalangeal (MP) joints. Three-phase bone scanning shows viability of the proximal phalanx of each finger. Which of the following is the most appropriate management?
(A) Amputation at the level of the distal interphalangeal joints and primary closure
(B) Amputation at the level of the MP joints and primary closure
(C) Amputation at the level of the MP joints and radial forearm flap reconstruction
(D) Amputation at the level of the proximal interphalangeal (PIP) joints and groin flap reconstruction
(E) Amputation at the level of the PIP joints and second metacarpal artery flap reconstruction
The correct response is Option D.
Because frostbite injuries can cause devastating loss of tissue, aggressive management is often needed to salvage and provide vascularized coverage over viable bone. The level of skin loss does not always correlate with the level of bone viability. A three-phase bone scan can be used to determine at which level the bone is viable. Amputation of nonviable bone is performed along with amputation of the nonviable soft tissue. To salvage the bone, well-vascularized coverage is required, with either a pedicle flap or a free flap.
Amputation at the level of the distal interphalangeal joints and primary closure would leave the middle phalanx nonvascularized. Amputating at the MP joint would sacrifice viable bone. Amputation at the level of the MP joints and radial forearm flap reconstruction would sacrifice viable bone, and the radial forearm flap would not be needed for coverage. Amputation at the level of the PIP joints and second metacarpal artery flap reconstruction is inappropriate because a second metacarpal artery flap would be of insufficient length to cover the open area.
Which of the following is associated with the use of pressure garments in the management of burn scars?
A) Decreased scar strength
B) Increased synthesis of tissue proteinases
C) Larger and less densely packed collagen fibers
D) Reduced differentiation of fibroblasts to myofibroblasts
The correct response is Option D.
Significant differences in scar contraction were observed between scars receiving pressure garment therapy and control burns that received no pressure. Pressure garments exert compressive forces perpendicular and parallel to the surface of the scar. These forces oppose the direction of contracture. One hypothesis is that wound tension acts upon integrins by stretching them, which leads to phosphorylation of focal adhesion kinase and upregulation of smooth muscle actin and collagen production. When compression is applied to incisional wounds perpendicular to the wound tension, scarring is minimized. This suggests that the mechanical forces applied to the scar can assist in reducing differentiation of fibroblasts to myofibroblasts, decreasing scar contraction and collagen deposition.
Scar strength was improved with pressure garment therapy compared with controls, with a 34% increase in ultimate tensile strength. Pressure garment therapy scars were also found to be composed of smaller, more densely packed collagen fibers.
Increased synthesis of tissue proteinases is a mechanism of corticosteroids.
A 24-year-old man presents to the emergency department after sustaining burns from a workplace fire in a kitchen. He has a suspected inhalation injury. Physical examination shows partial-thickness burns on the forearms and thighs, as well as on one ear. The plan is to use mafenide acetate as a topical antimicrobial dressing. Because of the suspected lung injury, mafenide should be used with caution because it places him at increased risk for which of the following?
A) Gray discoloration of skin
B) Hyperosmolality
C) Metabolic acidosis
D) Methemoglobinemia
E) Pruritis
The correct response is Option C.
The topical use of mafenide acetate, a carbonic anhydrase inhibitor, can prevent the conversion of hydrogen ions in the body to carbonic acid, leading to metabolic acidosis. In patients with an inhalation injury and respiratory acidosis, the use of mafenide acetate over large surface areas can be fatal. The use of mafenide is common in areas with cartilage, such as the ear. It is also useful for eschar penetration. Common adverse effects include pain with application.
Silver sulfadiazine is associated with leukopenia and hyperosmolality.
Silver nitrate can also be used, but it causes gray-to-black staining of the wound and can also be associated with electrolyte imbalances. Methemoglobinemia has also been reported with silver nitrate use.
A 51-year-old farmer is brought to the emergency department after sustaining extensive burns in a fertilizer explosion. Examination shows white phosphorus embedded in his burn wounds. In addition to burn resuscitation and examination of the wounds under ultraviolet light, application of which of the following is the most appropriate next step in management?
A) Calcium gluconate
B) Mafenide (Sulfamylon)
C) Mineral oil
D) Polyethylene glycol
E) Saline irrigation
The correct response is Option E.
White phosphorus is sustained in both military and civilian circumstances. It is commonly found in fireworks, fertilizers, and pesticide. It is extremely volatile and can ignite spontaneously upon exposure to air. Additionally, phosphoric acids form during combustion and further injure tissues.
Treatment mainstays include:
Immediate debridement of visible debris
Copious irrigation
Keep the area wet and covered with saline-soaked gauze
Cardiac monitoring and electrolyte evaluation.
Profound hypocalcemia, hyperphosphatemia, and sudden death have been associated with this injury.
Calcium gluconate gel is used in the management of hydrofluoric acid burns. Polyethylene glycol is used in the management of phenol and cresol burns. Mineral oil is used to isolate potassium, sodium, and magnesium from water, with which they react explosively. Mafenide (Sulfamylon) has no role in the immediate management of white phosphorus burns.
A 47-year-old man sustains a high-voltage electrical burn injury to the left upper extremity; a photograph is shown above. Physical examination shows swelling and tenseness of the forearm; there is no circumferential eschar. An exit wound is noted on the left foot. Adequate fluid resuscitation has been performed, and the patient is stable.
Which of the following is the most appropriate immediate management of the right forearm and hand?
(A) Observation
(B) Splinting
(C) Escharotomy
(D) Fasciotomy
(E) Amputation
The correct response is Option D.
Electrical injuries involving a charge of greater than 1000 volts are often misleading because the mildness of the superficial wounds frequently masks the serious underlying problems. Bone and muscle have greater resistance and thus generate significant heat, and the necrotic processes of these tissues are often hidden under viable skin. Serial excision of tissue is required to address this complication. Affected patients also have marked edema and rapidly increasing compartment pressures, which inhibit vascular inflow and can further worsen tissue necrosis. Muscle necrosis may lead to myoglobinuria, which if left untreated can result in myoglobin-induced renal failure. To prevent this life-threatening complication, the urine must be alkalized with administration of sodium bicarbonate, and urinary output must remain at a constantly high rate. Fasciotomies of the hand and forearm should be performed immediately for tissue salvage; the surgeon should continue to assess the viability of the tissue in the hand and forearm following fasciotomy.
Observation is obviously inadequate and even dangerous in a burn patient with compartment syndrome. Similarly, splinting alone will not prevent further injury to the extremity. Although escharotomy does not relieve compartment syndrome, it is a recommended first step in patients who have burn injuries with constricting eschar. Amputation prior to complete demarcation may be required in patients with infected or completely necrotic tissue.
A 19-year-old man who sustained burns to 40% of the total body surface area at 4 years of age comes to the burn clinic for consultation regarding correction of the scalp defect shown. Physical examination shows patchy alopecia of the temporal scalp and hypertrophic scarring. Which of the following is the most appropriate surgical procedure for reconstruction of this patient=s scalp?
(A) Hair transplantation with micrografts and minigrafts
(B) Orticochea flap
(C) Serial excision and closure
(D) Temporoparietooccipital (Juri) flap
(E) Tissue expansion
The correct response is Option E.
The patient shown has a large (>25 cm2) parietal scalp defect that resulted from a flame burn. It is clear that hair transplantation has already been attempted with minimal take and coverage. Hair transplantation with micrografts and minigrafts is a technique that has been described to treat large areas of burn alopecia. However, it is usually reserved for smaller areas, or as a revisional procedure to camouflage incisions that result from rotational flaps.
Tissue expansion is the preferred method for secondary reconstruction of a large parietal scalp defect. Approximately 50% of scalp can be reconstructed with expanded scalp tissue, although this may require multiple stages. Expander complication rates may be as high as 25% and may include infection, exposure, extrusion, and device failure. Scalp expansion in children is difficult. There is a higher incidence of infection and decreased tolerance of pain. Moreover, there is a risk of skull deformation after a prolonged period of expansion. Therefore, deferral until the patient reaches young adulthood is reasonable.
Direct closure in a staged manner with serial excision or as a single €‘stage procedure with rotation advancement flaps is appropriate for small to medium-sized defects of the anterior and parietal scalp. The size of this defect would preclude this therapy in this case.
Temporoparietooccipital flaps as described by Juri are optimally suited for reconstruction of large defects of the anterior scalp. Orticochea flaps are classically described for reconstruction of large defects of the occipital scalp. They are not useful for parietal defects because tissue advancement from the contralateral parietal scalp up over the vertex is often inadequate for defect closure.
A 19-year-old woman comes to the office for a follow-up examination 18 months after skin grafting for burns over 25% of her total body surface area that includes the face, neck, chest, and shoulders. Physical examination shows persistent restriction of neck excursion and lateral range of motion. A photograph is shown. Which of the following is the most appropriate management?
A) Compression therapy
B) Corticosteroid injection
C) Silicone sheeting
D) Skin grafting
E) Z-plasty tissue rearrangement
The correct response is Option E.
The patient described has a condition that is common among burn patients with significant burns to the neck area; that is, contracture band formation, even after primary attempts at skin grafting. Contractures are produced not only by absolute skin loss and/or skin contraction along a straight line scar, but also by the differential growth rate between the burn scar and the rest of the adjacent normal skin and tissues, especially in younger patients.
There are various techniques used to release contractures. Management depends on both the location of the contracture as well as the availability of unaffected adjacent skin. Methods of release include tissue expansion, local and distant flaps, ?alphabet plasties? (Z, W, V-Y, etc.), and skin grafting. The most appropriate option for the patient described is a Z-plasty, especially as she has failed a prior attempt at skin grafting. Through soft-tissue rotation, Z-plasty accomplishes three things: (1) lengthens a contracted scar, (2) breaks up a straight line, and (3) shifts soft-tissue contour.
Compression therapy/splinting is useful as an adjunct therapy but not as a primary treatment of this deformity. The patient described does not have a hypertrophic or keloid scar – it is a contracture band. Therefore, the injection of corticosteroids and silicone sheeting are not indicated in the treatment of this deformity.
The advantage of skin grafts, in general, is the transfer of new skin from a previously uninjured area of the body to the area in need with low donor site morbidity, though full-thickness grafts generally have larger donor site morbidity than split grafts. The disadvantage of skin grafts is that they tend to recontracture, necessitating further release through reoperation, as in the scenario described. Prolonged periods of postoperative physiotherapy and splinting are required to maximize aesthetic and functional results.
A 20-year-old college student is being evaluated because of painful blistering of his toes the morning after he walked two miles in snowy weather, wearing sandals and no socks. Which of the following best describes the primary beneficial effect of ibuprofen for this patient?
A ) Control of edema
B ) Control of pain
C ) Decreased secondary tissue damage
D ) Prevention of antiplatelet aggregation
E ) Speeding of demarcation
The correct response is Option C.
Thromboxane A2 is a powerful mediator of the inflammatory process responsible for secondary tissue damage in frostbite injuries. Ibuprofen blocks the cyclooxygenase cascade that results in the production of thromboxane A2. The negative effect of blockade of the cyclooxygenase is decreased production of prostaglandin I2 and E2, which are responsible for vasodilatation and antiplatelet aggregation. Although pain control is a beneficial result of the use of ibuprofen, many patients suffering from frostbite injuries require narcotic pain medications. Demarcation cannot be speeded by the use of ibuprofen and may require up to six months before amputation should be undertaken.
A 30-year-old man sustained a third-degree burn to his right arm from a flame while cooking over a grill. The burn is 5% total body surface area (TBSA). Two days after the injury, he undergoes debridement of the dorsal wrist and forearm. The paratenon is not present after the debridement. A bilaminate neodermis (Integra) graft is selected and placed on the wound. Use of this graft is associated with which of the following?
A) Decreased cost to the hospital
B) Decreased number of hospital stays
C) Decreased number of surgeries
D) Decreased risk for hypertophic scar
E) Increased skin sensation after reconstruction
The correct response is Option D.
The literature states that there is a decrease in hypertrophic scarring associated with the use of bilaminate neodermis (Integra) with burn reconstruction. The cost of the product is high. Use of the product requires a second surgery for the skin graft. There has not been any literature supporting improved sensation following use of the graft. The downside to the graft is that it can result in longer hospital stays for the patient in order to get the second surgery completed.
Which of the following skin substitutes contains foreskin-derived neonatal human fibroblasts and keratinocytes?
A ) AlloDerm
B ) Apligraf
C ) Biobrane
D ) Integra
E ) Surgisis
The correct response is Option B.
Apligraf is a permanent, biosynthetic, bilayered living construct of cultured foreskin-derived neonatal human keratinocytes and fibroblasts. They are cultured on a matrix consisting of bovine-type collagen.
AlloDerm is a human cryopreserved, acellular, cadaveric, de-epidermalized dermis. The complex is immunologically inert and becomes repopulated with host fibroblasts and endothelial cells.
Biobrane contains Type I porcine collagen peptides in a bilaminate of silicone film and nylon fabric.
Integra is a temporary bilaminate composed of silicone and a matrix of cross-linked bovine tendon collagen and shark-derived glycosaminoglycans.
Surgisis is derived from porcine small intestine and is processed into a biocompatible three-dimensional, extracellular matrix composed of collagen, noncollagenous proteins, and other biomolecules.
An otherwise healthy, 76-year-old woman sustains a deep partial-thickness facial burn following scald injury. No acute intervention is performed and the patient follows up in the clinic 6 weeks after the incident. She complains of pain in the right eye as well as frequent tearing. Physical examination of the eye shows 4 mm of lagophthalmos, conjunctival injection, and hypertrophic scarring on the upper lid with restrained motion. The surrounding skin on the cheek and forehead appears erythematous and indurated. Which of the following is the most appropriate treatment for this patient?
A) Contracture release and forehead flap
B) Contracture release and full-thickness skin grafting
C) Contracture release and placement of allograft
D) Contracture release and split-thickness skin grafting
E) Scar massage and eyelid taping
The correct response is Option B.
Facial burn injuries in the periorbital area must be quickly treated to support patient comfort and protect vision. Continued lagophthalmos and patient complaints warrant intervention, particularly with the degree of symptoms that the patient is expressing. The need for earlier intervention is specifically discussed in Klifto, et al. There is no indication for allograft placement following contracture release in this case, as a surface to graft upon should be present following contracture release in the eyelid. Of note, the contracture release usually occurs superficial to the orbicularis oculi and superior to the tarsal plate. Following contracture release, full-thickness skin grafts, but not split-thickness skin grafts, will minimize contracture after placement. Forehead flap reconstruction of the upper eyelid is a reasonable intervention and may be the most successful in preventing contracture recurrence, but it is not a treatment choice if the donor skin may be involved with the burn injury, as in the case of this patient.
A 43-year-old woman comes to the emergency department 2 hours after sustaining deep second-degree burns to the right elbow from a campfire. The wound measures 8 x 20 cm. After surgical excision, placement of autografts, and coverage with petrolatum gauze, which of the following dressings is most likely to promote graft survival?
A) Cotton balls and tie-over bolster dressing
B) Dry gauze and compressive wrap
C) Negative pressure wound therapy
D) Occlusive dressing
E) No additional dressing
The correct response is Option C.
In the patient described, the most effective way to fixate autografts is negative pressure wound therapy (NPWT). Several studies in burn patients have demonstrated the superiority of NPWT over the other conventional dressings listed. Whether staples or sutures are used has little effect on graft survival, although sutures may offer more precise graft placement. Most dressings for graft fixation use petrolatum gauze of some form, followed by some type of dressing that offers compression to fixate grafts. Dry gauze and a compressive wrap is the simplest option. Cotton balls with a tie-over bolster dressing are also effective, especially for small grafts. Larger surface areas are more difficult to secure with this method. A simple occlusive dressing, while acceptable for a donor site, will not effectively fixate autografts. NPWT offers good graft fixation, exudate removal, and promotion of local perfusion, which may explain the improved graft survival observed.
A 14 €‘year €‘old boy is brought to the office because he is unable to extend the proximal interphalangeal (PIP) joint of the long finger of the dominant right hand beyond 60 degrees of flexion. Six months ago, he sustained partial-thickness burns to the palmar surface of the long finger. The remaining fingers were spared. He has been performing active and passive range of motion exercises under the guidance of a therapist. Examination shows a thick scar extending the full width of the palmar skin and from the mid proximal phalanx to the distal interphalangeal flexion crease. With full passive flexion of the metacarpophalangeal (MCP) joint, the PIP joint can be extended nearly completely. Which of the following is the most appropriate management?
(A) Continued hand therapy and observation
(B) Daytime dynamic extension splinting and nighttime static extension splinting
(C) Injection of a corticosteroid into the scar and continued hand therapy
(D) Release of the contracture and full €‘thickness skin grafting
(E) Z €‘plasty lengthening of the scar and continuous static extension splinting
The correct response is Option D.
Despite optimal management of hand burns with splinting and occupational therapy, scar contractures may still occur. As in other contractures of the fingers, management depends on the elements responsible for the loss of motion. In the patient described, the severe PIP joint contracture shows adequate correction with MCP joint flexion, implying a primary derangement of the skin. Involvement of deeper structures (volar plate, collateral ligaments) would not correct with altered position of the MCP joint.
As a primary intervention, the optimal treatment of the patient described is division of the contracted cord and interpositional, full €‘thickness skin grafting.
For initial treatment and early, immature contracture management, therapy and dynamic splinting are critical interventions. In an established, mature burn scar, attempts at stretching the scar (continued hand therapy or dynamic extension splinting) will be unlikely to correct the defect.
Injection of a corticosteroid may be beneficial for keloids or hypertrophic scars; however, it would not correct the burn scar contracture in the patient described.
Correction of PIP joint contractures with more extensive dissection (joint release) requirements may devitalize tissues essential for skin graft take. In the scenario described and in the setting of secondary corrective surgery, local flaps such as the cross €‘finger flap may prove more useful.
Local tissue rearrangement (Z €‘plasty) is effective in narrow scars but will be difficult and likely ineffective in broad scars.
A 32-year-old man has severe pain and swelling of both hands after being exposed to hydrofluoric acid while working with a rust remover. On examination, there is significant edema, mottling, and exquisite tenderness of the index, long, and ring fingers of both hands. Digital pulses are present on Doppler ultrasonography.
Following copious irrigation of the hands with water, which of the following is the most appropriate next step in management?
(A) Irrigation with 1% copper sulfate
(B) Topical application of phenol
(C) Application of a calcium sulfate splint
(D) Local injection of 10% calcium gluconate
(E) Debridement of the wounds and coverage with split-thickness skin grafts
The correct response is Option D.
This patient has sustained chemical burns to both hands after coming in contact with hydrofluoric acid, a corrosive material derived from elemental fluoride and used in rust removal and plastic and pottery manufacturing. Hydrofluoric acid burns can result in necrosis of soft tissues and decalcification of bone; affected patients can have pain that persists for days. The mechanism of action of this type of burn is due to the high concentration of hydrogen ions within the tissues, as well as liquefaction necrosis caused by the soluble free fluoride ion. Following copious irrigation of the burn site with water to remove as much of the hydrogen ion as possible, 10% calcium gluconate should be injected locally in multiple small doses to prevent vascular compromise. The calcium will bind to the fluoride ion, resulting in immediate relief of pain. A topical calcium gluconate paste can be applied in patients who have less severe burns, and intra-arterial injection is advocated for patients with more severe burns.
Copper sulfate is used for irrigation in patients with phosphorus burns to identify buried particles of phosphorus. Phenol should not be applied because it can be absorbed through intact skin and further worsen injury. In patients who have sustained phenol burn injuries, topical application of polyethylene glycol or vegetable oil is recommended. Similarly, calcium sulfate (eg, plaster of Paris) can result in exothermic burns when used in a splint or cast. Debridement with split-thickness skin grafting should be considered only after the extent of demarcation of the injury is fully known; it may be necessary in patients who have persistent liquefaction necrosis, which manifests as unrelenting pain, even after treatment with calcium gluconate.
A 25-year-old man sustains a high-voltage electrical injury of the right upper extremity with an entrance wound over the volar aspect of the wrist. If increased compartment pressures are not adequately relieved in time, which of the following muscles is most likely to develop an ischemic contracture?
A) Brachioradialis
B) Extensor carpi radialis brevis
C) Flexor carpi radialis
D) Flexor digitorum profundus
E) Palmaris longus
The correct response is Option D.
The above patient did not undergo forearm compartment release and has flexion contractures of the interphalangeal joints of the fingers and thumb due to ischemic necrosis of the flexor digitorum profundus (FDP) and flexor pollicis longus (FPL).
Volkmann ischemic contracture is the end result of untreated compartment syndrome. The deeper muscles in the forearm sustain higher pressure sooner and for longer, causing them to be the most affected by compartment syndrome. The FDP to the middle and ring fingers lies against the ulnar and interosseous membrane in the deep compartment of the forearm. These two muscle segments, in addition to the remaining segments of the FDP to the index and small fingers and the FPL, are the most likely to develop contracture. All other muscles listed are more superficial. While brachioradialis, palmaris longus, extensor carpi radialis brevis, and flexor carpi radialis can all become necrotic in untreated compartment syndrome, FDP and FPL are the most likely to do so due to their depth in the forearm.
A 30-year-old man who sustained burns on 35% of the total body surface area 24 hours ago is being treated in the burn unit. The patient was resuscitated according to the Parkland formula and is maintaining adequate urine output. Gastric feeding access was established on initial presentation, and the patient is being fed according to his initial body weight. Which of the following clinical indices is most suggestive of the need to decrease his feeding to trophic feeds?
A) Early operative excision with planned start time in 8 hours
B) Hypotension requiring vasopressin support
C) Mild abdominal distension that is soft to palpation
D) Nasogastric output of 100 mL for the past 24 hours
E) Need for escharotomy
The correct response is Option B.
There is no doubt that nutritional support for burn patients is integral. A multidisciplinary approach to nutritional assessment and support is ideal, and general knowledge of the indications of when to delay or decrease enteral feeding is essential.
Since the patient has gastric and not post pyloric feeding access, nil per os (NPO) for eight hours allowing adequate gastric emptying to decrease risk of aspiration is necessary.
Gut mucosal integrity is important during the stress of large trauma including burn, and enteral feeding is the preferred modality of access. However, during times of extreme stress, decreased splanchnic flow can cause poor intestinal perfusion, and there is the possibility of gut ischemia due to increased metabolic demand of the gut. Decreasing the gastric feeds to trophic feeds is recommended to decrease the risk of inducing gut ischemia. Clinical indications for threatened intestinal perfusion include firm, obvious abdominal distension and gastric output greater than 200 mL per day; the patient doesn’t exhibit any of these clinical signs.
Hypotension requiring vasopressor support indicated decreased perfusion, which can lead to possible mismatch of gut perfusion with required metabolic demand. Trophic feeds are recommended for patients who exhibit signs of significant decreased perfusion requiring vasopressor support.
Escharotomy will increase fluid losses, but will not change caloric needs.
A 25-year-old man presents with partial-thickness burns involving 15% of the total body surface area that he sustained during a house fire. The patient is stabilized and resuscitated. Topical 1% silver sulfadiazine cream is applied to the burns. Which of the following properties is most characteristic of this antimicrobial agent?
A) Greatly enhanced efficacy when compounded with thiol chelators
B) Metabolic acidosis
C) Poor capacity for wound bed penetration
D) Poor efficacy against Candida albicans
E) Potential for transient leukocytosis
The correct response is Option C.
In the United States, silver is the most commonly used topical antimicrobial. It is available as a liquid solution of AgNO3 or ointments such as silver sulfadiazine (Silvadene). Despite its many advantages, its capacity to penetrate into the wound bed is limited to the surface epithelium, particularly in the presence of eschar because of the binding of silver ions to surface proteins. In this setting, different modalities should be used for optimal effects. Silver sulfadiazine is not only effective against Pseudomonas species and enteric bacteria, but it also provides coverage against fungi, including Candida albicans, with antimicrobial effects lasting up to 24 hours.
Regarding the potential for transient leukocytosis, silver sulfadiazine has been shown to cause reversible neutropenia, which usually improves within a few days after discontinuation of the agent.
Enhanced efficacy when compounded with thiol chelators is consistent with bismuth compounds, not silver. Bismuth is another heavy metal with antimicrobial properties. The most commonly used formulation of bismuth for wound care is bismuth subgalactate, found in xeroform (Covidien) gauze. This heavy metal disrupts biofilm formation by inhibiting polysaccharide capsule production in bacteria. Bismuth’s antibacterial activity is enhanced when compounded with thiol chelators.
Metabolic acidosis is associated with mafenide acetate use.
A 35-year-old man is admitted to the burn unit after sustaining superficial partial-thickness burns involving 25% of the total body surface area. Medical history includes an allergy to sulfonamide. The burns are cleaned, and silver nitrate–soaked dressings are applied. Which of the following is most likely in this patient?
A) Hyponatremia
B) Metabolic acidosis
C) Neutropenia
D) Painful application
E) Thrombocytopenia
The correct response is Option A.
Because of the skin’s important function as a microbial barrier, prevention of infection after burn injury is still one of the most difficult challenges in caring for burn patients. The development of effective topical antimicrobial agents has markedly reduced the incidence of invasive burn wound infection and sepsis. Topical therapy should be started after the initial wound debridement. The three most common topical antimicrobial agents are silver sulfadiazine (Silvadene), silver nitrate, and mafenide acetate (Sulfamylon).
Silver nitrate is typically delivered as a 0.5% solution as a wet dressing. Silver nitrate has excellent antibacterial properties and is effective for most Staphylococcus species and most gram-negative aerobes, including Pseudomonas. This agent is typically used when there is a history of sulfonamide allergy or when sensitivity to the other agents has developed. A common use of silver nitrate is in the setting of toxic epidermal necrolysis. Application is painless, but tissue penetration is poor. Concentrations above 5% are cytotoxic to healthy tissues. Because leaching of sodium, potassium, and calcium is common, this effect should be anticipated and replaced appropriately.
Painful application is associated with mafenide acetate (Sulfamylon). Mafenide acetate is delivered as suspension in a water-soluble base. As a result of its solubility, it has excellent tissue penetration and is often used in heavily contaminated wounds with thick eschar. Because of excellent cartilage penetration, it is also the agent of choice with ear burns. Mafenide acetate is highly effective against gram-negative organisms. Adverse effects include hypersensitivity reactions (7% of patients) and inhibition of carbonic anhydrase with a resultant hyperchloremic metabolic acidosis.
Silver sulfadiazine is the most common topical antimicrobial agent used. It has intermediate tissue penetration secondary to its limited water solubility. This agent has a good antibacterial spectrum, a low incidence of development of resistant organisms, and is applied painlessly. Transient leukopenia is a common adverse effect of silver sulfadiazine. This condition is self-limited and does not appear to increase mortality in burn patients. Switching to a different topical agent for a few days will allow the white blood cell count to return to normal.
Thrombocytopenia is not associated with silver nitrate.
A 2-year-old boy is brought to the emergency department because of a scald burn
sustained after he pulled a pot of boiling water off the counter. Examination
demonstrates deep partial thickness burns over the anterior and posterior trunk,
equaling 22% total body surface area. Oxandrolone is administered on admission
and continued in the weeks following resuscitation and reconstruction.
Administration of this drug is most likely to result in which of the following?
A) Decreased bone mineral content
B) Decreased mortality
C) Increased cardiac output
D) Increased serum concentrations of alanine aminotransferase (ALT) and aspartate
aminotransferase (AST)
E) Loss of lean body mass
The correct response is Option D.
Severe burns can lead to a physiologic hypermetabolic response, causing increased energy
expenditure and protein consumption. Long-term effects include muscle mass wasting and
delayed wound healing. To address these effects in patients with severe burns (including the
greater than 20% total body surface area burn in this patient), oxandrolone has been used to
combat the hypermetabolic response.
Oxandrolone is a synthetic testosterone derivative that is administered orally. During the
catabolic phase, it counteracts the hypermetabolic response, leading to improved clinical
outcomes including an increase in lean body mass and bone mineral content, as well as
decreased length of stay in the inpatient setting. It does not have an impact on mortality. In
the short-term, oxandrolone has been known to cause an increase in the liver enzymes alanine
aminotransferase and aspartate aminotransferase, but it is not associated with long-term
hepatotoxicity. The favorable effects of increased muscle mass extend to the myocardium,
and patients treated may display decreased cardiac output and resting heart rate.
REFERENCES:
1. Porro LJ, Herndon DN, Rodriguez NA, et al. Five-year outcomes after oxandrolone
administration in severely burned children: a randomized clinical trial of safety and
efficacy. J Am Coll Surg. 2012;214(4):489-502. doi: 10.1016/j.jamcollsurg.2011.12.038
A 59-year-old postal worker comes to the emergency department because of numbness and discoloration of the right thumb. He says he was outdoors for 8 hours in a temperature of -15°F (-26°C) and had taken ibuprofen before arrival. Physical examination shows distal bluish skin without capillary refill. A photograph of the thumb is shown. Which of the following is the most appropriate initial management?
A) Debridement or amputation of dead tissue, if necessary, to avoid infection
B) Debridement of any hemorrhagic blisters
C) Discontinue antiprostaglandins
D) Observe and allow the tissue to fully demarcate
E) Rapid rewarming with radiant heat
The correct response is Option D.
The decision to allow tissue to fully demarcate is essential in the scenario described because it is difficult to determine which tissue may survive in the immediate postinjury period. This period may be 6 months.
Clear blisters are debrided because they contain high concentrations of inflammatory mediators. Inflammatory mediators lead to greater tissue injury. Hemorrhagic blisters are not debrided because this may cause exposure of deep structures and increase the risk of desiccation and subsequent necrosis.
Early debridement and amputation are necessary if soft-tissue infection develops during the waiting period; otherwise, they are not indicated. Premature amputation risks sacrifice of potentially salvageable tissue.
Antiprostaglandins, either topical (such as 70% aloe cream) or oral (ibuprofen 12 mg/kg), are beneficial to block the cascade of arachidonic acid by cyclooxygenase and the inflammatory process. Beneficial effects of antiprostaglandins include vasodilatation and antiplatelet aggregation.
Rapid rewarming decreases further tissue damage as it halts both direct injury and continued release of secondary mediators. Submersion of the injured part in 104°F (40°C) water for 15 to 30 minutes is ideal. This maneuver stops ice crystal formation and reverses the deleterious effects of vasoconstriction. Use of radiant heat sources in frostbite can lead to iatrogenic injury due to uneven thawing and, in unusual cases, secondary thermal burn to insensate tissue. Before and after photographs are shown.
To minimize the risk for hypertrophic scar formation and subsequent skin contractures in a patient who has sustained partial-thickness burns of the neck, attempts at healing by second intention should be limited to a maximum of how many weeks?
(A) 1
(B) 2
(C) 3
(D) 4
(E) 6
The correct response is Option C.
To minimize the risk for development of hypertrophic scars and subsequent skin contractures in a patient who has sustained partial-thickness burns of the neck, the wound should not remain open for more than three weeks. According to the results of one study, hypertrophic scars formed in 33% of patients whose wounds healed within three weeks, compared with 78% of patients whose wounds were left open for more than 21 days.
Burn scar contractures of the neck can be released using Z-plasty, local flaps, or thick split-thickness or full-thickness grafts. The surgeon may need to release the platysma with the scar in order to restore full extension. Long-term postoperative splinting and compression are essential for graft take. Tissue expansion of unburned adjacent skin is another alternative for resurfacing the burned area.
A 25-year-old man who works as an electrician is brought to the emergency department by ambulance one hour after he fell from a ladder and grabbed a high-tension power line carrying approximately 50 kV with his right hand. Pulse rate is 120/min and blood pressure is 120/70 mmHg. Physical examination shows a burn mark over the right palm and a burn wound over the right scapula. No distal pulses are palpable. Which of the following is the most appropriate initial management of the wound to the upper extremity?
(A) Splinting of the hand and wrist in a position of function and elevation
(B) Topical application of mafenide and an occlusive dressing
(C) Escharotomy
(D) Fasciotomy
(E) Arterial grafting to the radial artery segment
The correct response is Option D.
Clinically, electrical injuries are divided into high- and low-tension injuries based on voltage. High-voltage injuries, as in this scenario, occur with contact of an electrical source greater than 1000 V. Electrical injuries of this magnitude usually result in significant myonecrosis as well as neural injury.
In the presence of such a significant injury, fasciotomy should be performed because continued muscle necrosis and swelling will certainly result in compartment syndrome. Decompression of the median nerve at the wrist should be ensured at the time of forearm fasciotomy. Other mainstays of treatment of electrical injuries to the upper extremity are repeated debridements of necrotic muscle and early flap coverage to decrease the incidence of amputation, infection, and renal failure. Escharotomy is the treatment for full-thickness thermal burns to the hand and arm. Mafenide acetate solution (Sulfamylon) would have efficacy for thermal burns in which penetration of cartilage is required. Arterial grafting may be required if there is evidence of a thrombosed radial artery, but this is not the most appropriate initial treatment. Splinting in a position of function is important but is not the most appropriate initial treatment.
A 4-year-old boy has wound cellulitis, pneumonia, and bacteremia one week after sustaining burns on 38% of the total body surface area in a house fire. He undergoes debridement of the wounds. Grafting is performed to reconstruct the resulting defects. Debrided tissue is sent for culture. While awaiting the results of culture, which of the following is the appropriate empiric antibiotic therapy?
A ) Ampicillin-sulbactam, ciprofloxacin, and tobramycin
B ) Penicillin G, clindamycin, and gentamicin
C ) Vancomycin and piperacillin-tazobactam
D ) Vancomycin, piperacillin-tazobactam, and amphotericin
E ) Vancomycin, piperacillin-tazobactam, and fluconazole
The correct response is Option C.
The most common bacteria causing burn wound infections include methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas, and Klebsiella. Empiric antibiotic therapy for the patient described would need to cover these gram-positive cocci and gram-negative rods.
Of the antibiotics listed, only vancomycin covers MRSA. Piperacillin-tazobactam is the most appropriate choice for pseudomonal coverage. Antifungal coverage with fluconazole or amphotericin is not necessary and is not supported by the literature. Antifungal prophylaxis remains controversial.
A 35-year-old man is admitted to the burn unit after sustaining superficial partial-thickness burns involving 25% of the total body surface area. Medical history includes an allergy to sulfonamide. The burns are cleaned, and silver nitrate–soaked dressings are applied. Which of the following is most likely in this patient?
A) Hyponatremia
B) Metabolic acidosis
C) Neutropenia
D) Painful application
E) Thrombocytopenia
Correct answer is option A.
Because of the skin’s important function as a microbial barrier, prevention of infection after burn injury is still one of the most difficult challenges in caring for burn patients. The development of effective topical antimicrobial agents has markedly reduced the incidence of invasive burn wound infection and sepsis. Topical therapy should be started after the initial wound debridement. The three most common topical antimicrobial agents are silver sulfadiazine (Silvadene), silver nitrate, and mafenide acetate (Sulfamylon). Silver nitrate is typically delivered as a 0.5% solution as a wet dressing. Silver nitrate has excellent antibacterial properties and is effective for most Staphylococcus species and most gram-negative aerobes, including Pseudomonas. This agent is typically used when there is a history of sulfonamide allergy or when sensitivity to the other agents has developed. A common use of silver nitrate is in the setting of toxic epidermal necrolysis. Application is painless, but tissue penetration is poor. Concentrations above 5% are cytotoxic to healthy tissues. Because leaching of sodium, potassium, and calcium is common, this effect should be anticipated and replaced appropriately. Painful application is associated with mafenide acetate (Sulfamylon). Mafenide acetate is delivered as suspension in a water-soluble base. As a result of its solubility, it has excellent tissue penetration and is often used in heavily contaminated wounds with thick eschar. Because of excellent cartilage penetration, it is also the agent of choice with ear burns. Mafenide acetate is highly effective against gram-negative organisms. Adverse effects include hypersensitivity reactions (7% of patients) and inhibition of carbonic anhydrase with a resultant hyperchloremic metabolic acidosis. Silver sulfadiazine is the most common topical antimicrobial agent used. It has intermediate tissue penetration secondary to its limited water solubility. This agent has a good antibacterial spectrum, a low incidence of development of resistant organisms, and is applied painlessly. Transient leukopenia is a common adverse effect of silver sulfadiazine. This condition is self-limited and does not appear to increase mortality in burn patients. Switching to a different topical agent for a few days will allow the white blood cell count to return to normal. Thrombocytopenia is not associated with silver nitrate.
An otherwise healthy 20-year-old man is brought to the emergency department after sustaining burns to the right forearm and upper arm while trying to light an outdoor grill. Examination of the burned extremity shows red, blistered, painful areas, as well as areas that are white in color and not tender to palpation. The burns are noncircumferential. The patient is breathing comfortably, and pulse oximetry is 99% on room air. This patient should be transferred to a burn center on the basis of which of the following criteria?
A) Age of the patient
B) Burn depth
C) Burn location
D) Burn mechanism
E) Total body surface area of the burn
The correct response is Option B.
The depth of this patient’s burns, being third-degree (white, not tender to palpation), would qualify him for transfer to a burn center for treatment. In this patient, the arm represents a total body surface area of 9% of the patient. He is young and otherwise healthy; thus, he does not warrant transfer based on age. The burn does not involve sensitive areas such as the face, hands, feet, or genitalia/perineum. Also, since this is not an electrical or chemical burn, and it occurred in an outdoor area, inhalation injury is unlikely.
A 58-year-old man is brought to the emergency department for frostbite injury of the right thumb. A photograph is shown. Which of the following is the inciting mechanism of the injury?
A) Failure of DNA repair mechanisms
B) Formation of extracellular ice crystals
C) Osteonecrosis secondary to vasoconstriction
D) Polymerization of intracellular amino acids
E) Vascular endothelial damage
The correct response is Option B.
Frostbite occurs by the formation of ice crystals in the intracellular and extracellular spaces. During the cooling process, the extracellular ice crystals form, and osmotic pressure increases, dragging water out of the cells. This leads to intracellular dehydration and an increase in intracellular electrolytes, proteins, and enzymes that lead to cell death. Additionally, there is vascular endothelial damage leading to intravascular thrombosis and decreased blood flow. Arteriovenous shunting occurs at the capillary level, and end-organ tissue damage is compounded.
During the warming process, there is an influx of fluid back into the cells, causing intracellular swelling. The warming process also allows reflow, vasodilation, and reactive hyperemia to occur, leading to increased inflammatory mediators causing further cell death.
Frostbitten extremities should be rapidly rewarmed in water at a temperature of 104.0°F (40.0°C). Typically, rewarming can be completed in 20 to 30 minutes. Adjunctive use of anti-inflammatory medications and anticoagulants also has been described. Patience is required in determining which areas need debridement.
An otherwise healthy 22-year-old man is brought to the emergency department after sustaining full-thickness skin loss to the hands. Two-stage reconstruction is planned using a bilaminate neodermis (Integra), followed by skin grafting and simple gauze dressings. Which of the following is the average time for maturation (time from application to removal of silicone layer) of Integra with simple gauze dressings only?
A) 1 week
B) 3 weeks
C) 6 weeks
D) 9 weeks
E) 12 weeks
The correct response is Option B.
Integra is a bilaminar skin substitute, composed of a silicone outer layer (mimicking the epidermis) and a biologic scaffold for the inner, dermal layer. Typical maturation (time from application to removal of silicone layer) is 21 days. This process can be accelerated with the use of negative-pressure dressings, but that is not described in this scenario.
A 5-year-old boy is brought to the emergency department after he sustained burns in a gasoline fire. Physical examination shows burns to 70% of the total body surface area, including the right ear (shown). Which of the following is the most appropriate initial management of the burns to this patient €™s ear?
(A) Application of mafenide acetate (Sulfamylon) cream and auto-amputation
(B) Costochondral reconstruction with a temporoparietal flap
(C) Debridement and coverage with a retroauricular pocket flap
(D) Excision and full-thickness skin grafting
(E) Excision and unmeshed split-thickness skin grafting
The correct response is Option A.
Ear burns are usually aggressively managed with mafenide acetate (Sulfamylon) cream, monitoring for chondritis, and allowing the severely burned region to auto-amputate. This is especially true for large total body surface area (TBSA) burns such as the one sustained by the patient described, where large areas of excision and grafting must be done to save the patient €™s life. This is largely a problem of ear deformity, not function, and therefore has a lower priority.
Mafenide acetate (Sulfamylon) cream is the best topical antibiotic agent suitable for the ear because it penetrates the eschar and cartilage. It is applied twice daily. Trauma to the ear by dressings, endotracheal tapes, or pillows should be avoided. The eschar should not be completely debrided, as it acts as a biological dressing that prevents desiccation.
The more aggressive managements of costochondral reconstruction or retroauricular flap reconstruction are not warranted in the acute phase and can limit future reconstructive options.
Excision and full-thickness skin grafting can be considered in the intermediate management but are generally contraindicated in such a large burn after the wounds become heavily colonized. Excision and split-thickness skin grafting can be considered as well.
A 50-year-old woman with a history of hypertension is brought to the hospital 1.5 hours after sustaining burn injuries in a house fire. Initial examination shows deep, second-degree burns (partial-thickness) to 35% of the trunk, non-circumferential third-degree burns (full-thickness) to 5% of the left forearm, and first-degree burns to 2% of the head. In addition to time from injury, which of the following common aspects of the burn evaluation should be used in both the Parkland formula and Brooke formula for determining fluid resuscitation in this patient?
A) Total body surface area (TBSA) (determined by first-, second-, and third-degree burns), gender, weight
B) TBSA (determined by first-, second-, and third-degree burns), weight
C) TBSA (determined by second- and third-degree burns), age, weight
D) TBSA (determined by second- and third-degree burns), gender, weight
E) TBSA (determined by second- and third-degree burns), weight
The correct response is Option E.
While there are different resuscitation formulas for initial burn resuscitation, such as the Brooke formula or the Parkland formula, they rely on giving a certain amount of fluid multiplied by total body surface area (as determined by partial- and full-thickness burns) and weight in kilograms of the patient. The fluid is then given initially as determined from time of injury, and divided into half given in the first 8 hours of injury and then half in the next 16 hours. This is a guideline only and resuscitation can be altered based on physiologic response, such as urine output. Gender and age are not a consideration and first-degree burns are not used in the calculation of total body surface area.
A 63-year-old man who was in a house fire has burns on 55% of his body including the upper limbs, chest, abdomen, and left leg. He underwent escharotomies and has been resuscitated, but he requires mechanical ventilation because of an inhalation injury. He has an evolving acute kidney injury. A photograph is shown. Immediate excision is planned for management of a suspected fungal infection of the burn wounds. Which of the following is the most appropriate method for initial excision in this patient?
A) Excision down to fascia without a tourniquet
B) Excision down to viable tissue using tumescence
C) Excision down to viable tissue with a tourniquet
D) Excision down to viable tissue without a tourniquet
E) Hydrosurgical debridement without a tourniquet
The correct response is Option A.
The best method for initial excision in this critically ill patient is excision down to fascia (fascial excision). Excision down to viable tissue (tangential excision) with or without a tourniquet would result in a large amount of blood loss, which would be a significant physiologic insult for this patient; additionally, it may not eradicate the suspected fungal infection. Tangential excision using tumescence may not result in significant blood loss, but the ability to judge viable from nonviable tissue is compromised, and this approach would have a high likelihood of requiring further debridement to achieve a healthy tissue bed unless performed by extremely experienced burn surgeons. Fascial excision is also much faster than tangential excision, which is an important consideration in this critically ill patient. Hydrosurgical debridement is adequate for superficial burns but has no role in a large flame burn and would result in excessive blood loss and operative time.
A 35-year-old man is brought to the emergency department because of deep burn injury to the dorsum of the index, middle, and ring fingers of the dominant left hand (shown) resulting from direct contact with a hot motorcycle engine during a motor vehicle collision. On tangential excision, tendons are exposed in each finger and loss of the paratenon is noted. Which of the following is the most appropriate surgical management?
(A) Split-thickness skin grafting
(B) Dorsal metacarpal artery flaps
(C) Cross-finger flaps
(D) Reverse radial forearm flap
(E) Groin flap
The correct response is Option D.
Because the paratenon has been removed, immediate split-thickness skin grafting will result in areas of graft loss. Dressing changes could be performed followed by grafting on a granulated bed. This method of treatment risks tendon desiccation while awaiting granulation tissue.
Dorsal metacarpal artery flaps can be useful in reconstructing dorsal hand and proximal finger defects. To repair a dorsal finger defect more distally, a reverse dorsal metacarpal artery flap could be used.
Cross-finger flaps use dorsal skin of adjacent fingers to resurface palmar defects. A variation of the cross-finger flap can be used to resurface a dorsal defect. This requires de-epithelialization of the flap and then skin grafting of the deeper surface of the flap.
The groin flap is a pedicled flap based on either the superficial circumflex iliac artery or the superficial inferior epigastric artery that can resurface wounds of the upper extremity. It has the disadvantages of requiring two surgical stages and the hand remaining dependent during the initial period of flap attachment, which can encourage edema and stiffness. In addition, groin flaps are bulky and require revisional surgery on the dorsal hand.
A reverse radial forearm flap would be the best choice for resurfacing the dorsal hand and fingers because it is soft, thin, and compliant. This may be most safely accomplished in stages with syndactylization performed at a second stage. This flap, however, has been longitudinally split to simultaneously resurface two areas of the hand. The two main disadvantages of this flap include the sacrifice of a major artery and an unaesthetic and potentially unstable grafted donor site.
