TCRN TCRN Burn and Inhalation Injuries 4 — Questions and Answers
Question 1: A burn patient develops myoglobinuria after electrical injury. What is the minimum target urine output to prevent acute kidney injury?
- 0.5 mL/kg/hr
- 1–2 mL/kg/hr (Correct answer)
- 3–5 mL/kg/hr
- 0.25 mL/kg/hr
Correct answer: 1–2 mL/kg/hr
With myoglobinuria, urine output should be increased to 1–2 mL/kg/hr (with IV fluids and possible sodium bicarbonate to alkalinize urine) to flush myoglobin and prevent tubular obstruction.
Question 2: Which sign indicates that a burn patient's inhalation injury has progressed to involve the lower airway?
- Singed nasal hairs and facial burns
- Stridor and hoarseness on presentation
- Wheezing and bronchospasm on auscultation (Correct answer)
- Soot in the oropharynx
Correct answer: Wheezing and bronchospasm on auscultation
Wheezing and bronchospasm indicate lower airway involvement from inhaled toxins and heat, while stridor and hoarseness suggest upper airway injury.
Question 3: What is the rationale for NOT using iced water or ice packs for initial burn cooling?
- Ice causes further tissue damage by direct freezing and hypothermia (Correct answer)
- Cold temperatures accelerate bacterial colonization of the wound
- Ice delays neutrophil migration needed for early healing
- Cold application increases pain and patient distress
Correct answer: Ice causes further tissue damage by direct freezing and hypothermia
Ice and iced water can cause vasoconstriction and hypothermia, worsening tissue damage; cool (not cold) running water at 15–25°C for 20 minutes is recommended.
Question 4: A patient transferred from an outside hospital with 50% TBSA burns has received 3 liters of NS. On arrival, the patient is in burn shock. What is the most appropriate fluid adjustment?
- Continue normal saline at the same rate and reassess in 1 hour
- Recalculate Parkland formula from time of injury and adjust LR rate accordingly (Correct answer)
- Administer 2L boluses of LR until hemodynamic stability
- Switch to colloid (albumin) as first-line resuscitation fluid
Correct answer: Recalculate Parkland formula from time of injury and adjust LR rate accordingly
The Parkland formula should be recalculated from the time of injury, credit given for fluids already received, and the remaining volume adjusted using lactated Ringer's.
Question 5: Which laboratory finding is most consistent with cyanide toxicity in a burn victim from a closed-space fire?
- Elevated carboxyhemoglobin with normal lactate
- High anion gap metabolic acidosis with elevated serum lactate (Correct answer)
- Respiratory alkalosis with normal base excess
- Hypochloremic metabolic alkalosis
Correct answer: High anion gap metabolic acidosis with elevated serum lactate
Cyanide inhibits cytochrome oxidase, blocking cellular respiration and causing a high anion gap lactic acidosis with markedly elevated lactate levels.
Question 6: Which burn wound finding indicates the need for skin grafting rather than expectation of spontaneous healing?
- Superficial partial-thickness burn with intact blisters
- Deep partial-thickness burn not healed by 14–21 days (Correct answer)
- Burn wound with pain on exposure to air
- Burn wound with moist pink appearance and brisk capillary refill
Correct answer: Deep partial-thickness burn not healed by 14–21 days
Deep partial-thickness burns that have not healed within 14–21 days are unlikely to close without hypertrophic scarring and require surgical skin grafting.
Question 7: A patient with inhalation injury is intubated and mechanically ventilated. Which ventilator strategy is preferred to minimize ventilator-induced lung injury?
- High tidal volume (12–15 mL/kg IBW) with low PEEP
- Low tidal volume (6 mL/kg IBW) with permissive hypercapnia (Correct answer)
- Pressure-controlled ventilation targeting PaCO2 < 35 mmHg
- High-frequency oscillatory ventilation as first-line mode
Correct answer: Low tidal volume (6 mL/kg IBW) with permissive hypercapnia
Lung-protective ventilation using low tidal volumes (6 mL/kg IBW) with permissive hypercapnia minimizes barotrauma and volutrauma in inhalation injury patients.
TCRN TCRN Burn and Inhalation Injuries 4
A burn patient develops myoglobinuria after electrical injury.
What is the minimum target urine output to prevent acute kidney injury?