Delayed Burn Resuscitation with Inhalation Injury and Limited Allograft
A 28-year-old woman, 62 kg, is rescued from a house fire and arrives 8 hours after injury. She has flame burns over 42% TBSA, 25% full thickness, with circumferential burns of the chest and both upper arms, singed nasal hair, carbonaceous sputum, hoarseness, and a carboxyhemoglobin of 18%. She is intubated. Heart rate is 132/min, BP 86/52 mmHg, urine output 12 mL/h for the last 3 hours, core temperature 35.1 °C, lactate 4.6 mmol/L, and haematocrit 52%. She received only 1,200 mL of Ringer's lactate at a peripheral hospital. The burn unit has one operating theatre available and limited allograft. She is 6 weeks postpartum and breastfeeding. The referring team asks whether to give colloid and how much fluid to run.
1. Calculate her fluid requirement and outline your resuscitation plan, including endpoints and the role of colloid.
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Calculation. Parkland formula: 4 × 62 × 42 = 10,416 mL in 24 hours, with half (5,208 mL) due in the first 8 hours from injury. She is already 8 hours out and has received only 1,200 mL, so she is profoundly under-resuscitated. Do not give the entire calculated deficit as one rapid bolus: delayed burn shock with inhalation injury is highly prone to fluid creep. Give 500–1,000 mL aliquots of Ringer's lactate over 30–60 minutes and reassess after each aliquot.
Endpoints. Target urine output 0.5–1.0 mL/kg/h (31–62 mL/h), MAP above 65 mmHg, improving lactate and base deficit, warm extremities, and acceptable peak airway pressures. Inhalation injury increases fluid needs but is not a reason to double the formula.
Colloid. Reserve 5% albumin for after the first 12–24 hours, or for patients who remain hypotensive despite adequate crystalloid. Early colloid has not been shown to improve survival. For the carboxyhemoglobin of 18%, continue 100% oxygen; consider hydroxocobalamin if cyanide exposure is suspected because of persistent lactic acidosis after adequate resuscitation. Recheck electrolytes, ionized calcium, and hemoglobin frequently. Avoid over-resuscitation, which causes abdominal compartment syndrome and pulmonary edema.
2. When would you excise and graft, and how would you prioritize coverage with limited allograft?
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Once resuscitation is underway and the patient is stable, I would perform early excision within 48–72 hours, starting with the circumferential chest and arm burns and the full-thickness areas. Early excision reduces wound sepsis and catabolism, but it should not be done during active shock. Stage the surgery: excise no more than about 20% TBSA at one operation in a patient with inhalation injury and limited resources, and reassess coagulation, temperature, and acid–base status between stages.
Coverage priority. Cover functional and exposed areas first: hands, joints, and the chest wall. Use meshed split-thickness autograft (1:1.5) for definitive coverage where possible. With limited allograft, use it as temporary cover over excised full-thickness wounds, then replace it with autograft as donor sites heal. Xenograft, amnion, or synthetic temporary dressings can bridge if allograft is unavailable, but they do not provide permanent cover. Reharvest scalp donor sites early because they heal fastest. Avoid leaving large excised areas open; if autograft is exhausted, use allograft plus planned re-grafting. The chest escharotomy should be released urgently if ventilation is compromised, even before formal excision.
3. On day 2, peak airway pressures rise to 42 cmH2O, urine output falls to 10 mL/h, and bladder pressure is 28 mmHg. How do you manage this?
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This suggests abdominal compartment syndrome (ACS) with organ dysfunction: bladder pressure above 20 mmHg plus oliguria and rising airway pressures. First, reduce ongoing fluid creep: slow crystalloid, reassess whether the patient is over-resuscitated, and use colloid or diuretics only after intravascular volume is adequate. Decompress the gut with a nasogastric tube and rectal tube, ensure adequate sedation and neuromuscular blockade, and position the patient to reduce abdominal wall tension. Check for and release any constricting abdominal or chest escharotomy wounds.
Measure bladder pressure every 4 hours. If ACS persists with oliguria, rising airway pressures, or acidosis, perform decompressive laparotomy and leave the abdomen open with a temporary closure. This is a damage-control manoeuvre, not a failure of burn care. Continue monitoring for sepsis, acute kidney injury, and rhabdomyolysis. Avoid nephrotoxic drugs and adjust antibiotic doses. Document the fluid balance and aim for the lowest crystalloid volume that maintains urine output and perfusion, because over-resuscitation is the commonest driver of ACS in burns.