Burn & Burn Reconstruction Flashcards
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
The correct response is Option C.
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.
2018
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.
2018
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.
2018
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.
2018
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.
2018
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.
2018
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.
2017
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.
2017
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.
2017
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.
2017
A morbidly obese woman is brought to the emergency department after being found unconscious at home. Her family reports that both of the patient’s arms were pinned beneath her body when emergency medical service responders arrived. Physical examination shows tense swelling of the upper extremities. The now conscious patient reports severe pain to passive extension of the digits. In addition to appropriate urgent operative management, the surgeon should anticipate which of the following?
A) Decreased glomerular filtration rate
B) Hypercalcemia
C) Hyperglycemia
D) Hypokalemia
E) ST-segment elevation
The correct response is Option A.
This patient has bilateral upper extremity compartment syndrome. The emergency department examination of concern for a long-standing period of upper extremity ischemia. The surgeon should anticipate rhabdomyolysis and its consequent renal and metabolic disorders. Supportive treatment should be undertaken. Hyperkalemia is common in rhabdomyolysis manifesting as peaked T waves on ECG as serum potassium concentrations rise. Glucose D50W, 50 mL intravenously, plus regular insulin (5 to 10 units) move potassium from the extracellular fluid to the intracellular fluid. Intravenous mannitol increases renal blood flow (GFR), attracts fluid from the interstitium (thereby counterbalancing hypovolemia), increases urinary flow (prevents myoglobin cast obstruction), and functions as a free radical scavenger. Allopurinol may be helpful in reducing the production of uric acid. It also acts as a free radical scavenger.
Hypocalcemia is commonplace in the initial phase of rhabdomyolysis; however, it does not usually require correction because this would increase the risk of intramuscular calcium deposition. Indication for correcting hypocalcemia would be impending seizures.
2016
A 154-lb (70-kg) man is evaluated 1 hour after sustaining deep partial-thickness burns to 50% of his total body surface area when attempting to light a gas grill. Paramedics administered 2 L of intravenous fluid during ground transport. Using the Parkland formula, which of the following is the starting rate for fluid resuscitation in this patient?
A) 375 mL/hr
B) 437 mL/hr
C) 583 mL/hr
D) 714 mL/hr
E) 875 mL/hr
The correct response is Option D.
The Parkland formula estimates the amount of crystalloid fluid needed for resuscitation of the burn patient, over the first 24 hours after injury. Volume needed = 4 mL × mass (kg) × % TBSA × 100. This patient would require 4 × 70 × 50% × 100 = 14,000 mL over the first 24 hours. Half of this, or 7 L, is given in the first 8 hours after injury. Because the patient received 2 L prior to arrival, during the first hour he would still need 5 L over the next 7 hours, or 714 mL/hr. Eight hours after injury, he would receive the other half, over 16 hours, or 437 mL/hr. It should be stressed that the Parkland formula serves as an initial guide to fluid resuscitation, and that actual volumes are titrated up or down, depending on urine output.
2016
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.
2016
A 4-year-old boy is brought to a small community hospital by his grandmother, who reports that he fell into a bathtub filled with hot water while under the care of his stepfather. Physical examination shows deep partial-thickness burns on the lower extremities, including the feet, with a clear line of demarcation on the upper ankles; there are no splash marks. Multiple bruises scattered across the chest and periorbital ecchymoses are noted. Child abuse is suspected. Which of the following is the most appropriate next step?
A) Admit the patient to the community hospital for a full skeletal survey
B) Admit the patient to the community hospital for local wound care
C) Notify local police to apprehend the stepfather
D) Transfer the patient to a burn center by emergency medical services
E) Transfer the patient to a burn center by private vehicle
The correct response is Option D.
This child meets several criteria for transfer to a burn center: suspected child abuse, significant burns to the hands or feet, and a history that does not match the physical examination. While local police and the department of social services should be notified about this case, the role of the burn care provider is to make sure that the patient receives appropriate treatment and is transferred or discharged to a safe environment. The child will require assessment of the household by a social worker, as well as a pediatric consult to help look for other occult injuries, such as acute or healing long-bone fractures. Transfer to a burn center by private vehicle, despite the wishes of the family, would be placing the child at excessive risk for further injury. Transfer must be coordinated and performed by emergency medical services.
2016
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.
2016
A 154-lb (70-kg), 45-year-old man undergoes excision and skin grafting after sustaining total body surface area burns to over 40% of his body. Using the Curreri formula, which of the following is this patient’s total daily caloric need?
A) 2250 kCal/day
B) 3350 kCal/day
C) 4450 kCal/day
D) 5550 kCal/day
E) 6650 kCal/day
The correct response is Option B.
The Curreri formula is used to calculate caloric needs: 25 kCal/kg/day + 40 kCal * %TBSA/day. So 25 × 70 + 40 × 40 = 3350 kCal/day.
2016
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 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.
2022
