What is the indicator of a good response to resuscitation in a burn patient with 40% total body surface area (TBSA) burns?

Urine Output is the Primary Indicator of Good Response to Resuscitation in Burn Patients

Urine output is the key parameter to guide fluid resuscitation in burn patients and serves as the primary indicator of adequate response to resuscitation, with a target of 0.5-1 mL/kg/hour in adults with thermal burns. 1

Why Urine Output is the Gold Standard

• Urine output is considered the easiest and fastest way to adjust fluid resuscitation rates and is universally recommended as the cornerstone monitoring parameter in burn resuscitation protocols 1, 2

• For a 40% TBSA burn patient, maintaining urine output of 0.5-1 mL/kg/hour indicates adequate tissue perfusion and appropriate fluid resuscitation 1, 2

• This parameter has been validated across multiple international burn guidelines and is specifically emphasized in both adult and pediatric burn management protocols 1

Why Other Parameters Are Secondary

Pulse pressure (Option A): While hemodynamic parameters can be useful, they are considered adjunctive rather than primary indicators 1

Mixed venous pressure (Option B): Advanced hemodynamic monitoring is reserved for patients with hemodynamic instability and/or persistent oliguria despite resuscitation, not as a first-line indicator 1, 3

CVP (Option D): Central venous pressure monitoring is part of advanced hemodynamic assessment but should be used in combination with urine output, particularly valuable in patients with hemodynamic instability 1, 3

Clinical Algorithm for Monitoring Response

1. Primary monitoring: Hourly urine output targeting 0.5-1 mL/kg/hour 1, 2

2. Adjust fluid rates based on urine output to avoid both under-resuscitation (which leads to burn shock) and over-resuscitation ("fluid creep") 1

3. Add advanced monitoring (echocardiography, cardiac output monitoring, CVP) only if hypotension persists despite appropriate fluid resuscitation or if oliguria continues 1, 3

4. Monitor arterial lactate as an additional parameter in combination with urine output 1

Critical Pitfalls to Avoid

• Over-resuscitation ("fluid creep") is associated with increased morbidity, longer hospital stays, increased mechanical ventilation time, and abdominal compartment syndrome 1, 2

• Under-resuscitation leads to inadequate tissue perfusion and burn shock 1

• Resuscitation formulae (Parkland, Brooke) provide only initial estimates and must be adjusted based on clinical response, primarily urine output 1, 4

• A systematic review found that while hemodynamic monitoring showed some survival benefit in observational studies, randomized controlled trials found no survival advantage over urine output monitoring alone 5

The answer is C: Urine output is the most reliable and practical indicator of good response to resuscitation in this burn patient.