What is the indicator of a good response to treatment in a patient with a 40% deep flame burn, after resuscitation and 100% oxygen therapy, in the Intensive Care Unit (ICU)?

Indicator of Good Response to Resuscitation in Severe Burn Patients

Urine output is the key indicator of adequate resuscitation response in this patient with 40% deep flame burns, with a target of 0.5-1 mL/kg/hour. 1, 2, 3

Primary Monitoring Parameter

Urine output remains the simplest, fastest, and most reliable parameter to guide fluid resuscitation in severe burn patients. 1, 3, 4 The target range of 0.5-1 mL/kg/hour serves as the cornerstone for adjusting fluid administration rates during the acute resuscitation phase. 2, 4

• This parameter directly reflects end-organ perfusion and intravascular volume status without requiring invasive monitoring 3
• Hourly urine production allows for rapid, real-time adjustments to fluid therapy 3, 4
• Both under-resuscitation and over-resuscitation ("fluid creep") increase morbidity, making urine output monitoring critical for avoiding both extremes 1, 3

Role of Advanced Hemodynamic Monitoring

While urine output is primary, advanced hemodynamic monitoring should be considered when standard parameters fail to guide resuscitation adequately or when hemodynamic instability persists despite appropriate fluid administration. 1, 2

When to Add Advanced Monitoring:

• Persistent hypotension despite adequate fluid resuscitation requires evaluation of cardiac function and intravascular volume status using echocardiography or alternative hemodynamic monitoring 1, 2
• Burns >30% TBSA may benefit from extended hemodynamic monitoring 5
• Pre-existing cardiopulmonary disease or inhalation injury definitively requires advanced monitoring 5

Specific Advanced Parameters:

• Central venous pressure (CVP) can guide fluid resuscitation in patients with hemodynamic instability and/or oliguria 2
• Cardiac output monitoring helps optimize resuscitation when standard parameters are inadequate 2, 6
• Transpulmonary thermodilution can detect initial hypovolemia that may not be reflected by blood pressure and urine output alone 6
• Lactate levels provide additional information about tissue perfusion and should normalize within 24-32 hours 6

Critical Pitfalls to Avoid

Over-resuscitation is as dangerous as under-resuscitation. 1, 3, 4 A retrospective study showed that under-responders (requiring excessive fluid for inadequate urine output) had 44% mortality compared to 11% in patients with expected response. 7

• Excessive fluid administration increases length of mechanical ventilation, hospital stay, and risk of abdominal compartment syndrome 1, 4
• Urine output exceeding 1 mL/kg/hour indicates over-resuscitation and fluid rates should be reduced 4
• The Parkland formula (2-4 mL/kg/%TBSA) is only an initial estimate and must be adjusted based on clinical response 2, 3

Answer to the Question

The correct answer is C: Urine output. This is the primary indicator recommended by current guidelines for monitoring good response to resuscitation in severe burn patients. 1, 2, 3, 4

• Pulse pressure (Option A) is not specifically validated as a primary resuscitation endpoint in burn patients
• Mixed venous oxygen saturation (Option B) requires invasive monitoring and is not a first-line parameter
• CVP (Option D) has a role in advanced monitoring but is secondary to urine output and requires invasive access 2