# Initial Assessment and Resuscitation of the Burn Patient

## Introduction
Burns are a leading cause of morbidity and mortality worldwide. Approximately 450,000 burn injuries require medical treatment annually in the United States. Management requires a systematic approach following ATLS principles with burn-specific modifications. Early, aggressive resuscitation is critical for survival in major burns. Multidisciplinary burn team management improves outcomes.

## Initial Assessment

### Primary Survey (ABCDE)

#### Airway
Highest priority: airway compromise is the leading cause of early death in burn patients. Indicators of inhalation injury: Facial burns, singed nasal hair, singed eyebrows. Carbonaceous sputum, soot in oropharynx.

Hoarseness, stridor, wheezing. History of enclosed-space fire. Altered mental status. **Early intubation** is critical: airway edema progresses rapidly during resuscitation (peak at 12-24 hours).

If in doubt, intubate early — waiting until edema develops makes intubation extremely difficult or impossible. Use an uncut endotracheal tube (facial swelling may dislodge a cut tube). Consider awake fiberoptic intubation if airway is edematous but patent.

#### Breathing
100% oxygen via non-rebreather (treats carbon monoxide and cyanide). Assess for circumferential chest burns restricting ventilation. Chest escharotomy if thoracic compliance compromised. Carbon monoxide poisoning: carboxyhemoglobin (COHb) level.

Pulse oximetry is unreliable (reads falsely normal). COHb >10% significant; >25% severe; >60% often fatal. Treatment: 100% FiO2 (half-life of COHb reduced from 4 hours to 45 minutes). Hyperbaric oxygen: controversial; consider for COHb >25%, neurological symptoms, pregnancy.

Cyanide poisoning: from combustion of synthetic materials (polyurethane, nylon). Lactic acidosis with normal PaO2. Treatment: hydroxocobalamin (Cyanokit) preferred; sodium thiosulfate.

#### Circulation
Two large-bore peripheral IVs (may be placed through burned skin if necessary). Lactated Ringer's solution initiated immediately. Central venous access if peripheral access inadequate. Blood pressure may be unreliable in circumferential extremity burns.

#### Disability
Glasgow Coma Scale. Consider carbon monoxide or cyanide poisoning if altered mental status. Associated traumatic brain injury (explosion, falls).

#### Exposure
Remove all clothing, jewelry, and constricting items. Prevent hypothermia: warm environment, warm IV fluids, warming blankets. Burns impair thermoregulation — hypothermia worsens outcomes.

### Secondary Survey
Complete head-to-toe examination. Estimate burn size and depth. Identify associated injuries (blast, fall, MVA). Obtain history: mechanism, enclosed space, time of injury, tetanus status, medications, allergies, medical history.

## TBSA Estimation

### Rule of Nines (Adults)
Head and neck: 9%. Each upper extremity: 9%. Anterior trunk: 18%. Posterior trunk: 18%. Each lower extremity: 18%. Perineum: 1%.

### Lund-Browder Chart
Age-adjusted TBSA calculation (more accurate, especially in children). Head proportionally larger in children (18% at birth, decreasing with age). Lower extremities proportionally smaller in children. Gold standard for accurate TBSA estimation.

### Palm Method
Patient's palmar surface (hand including fingers) ≈ 1% TBSA. Useful for scattered or small burns. Also useful for estimating unburned areas in large burns (subtract from 100%).

### Key Points
Only include partial-thickness (second-degree) and full-thickness (third-degree) burns in TBSA calculation. Do NOT include superficial (first-degree) burns in TBSA. Overestimation of TBSA is common and leads to over-resuscitation (fluid creep).

<image>Illustration comparing the Rule of Nines for burn TBSA estimation in adults versus the Lund-Browder chart for children. The left panel shows an anterior and posterior view of an adult body with each body region labeled with its percentage: head 9%, each arm 9%, anterior trunk 18%, posterior trunk 18%, each leg 18%, perineum 1%. The right panel shows an anterior and posterior view of a pediatric body (age 1 year) with age-adjusted percentages using the Lund-Browder chart, showing the head at 18% and each leg at 14%, with a reference table showing how head and leg percentages change with age from birth to adult. Both panels use color-coded regions for clarity.</image>

## Burn Depth Classification

| Depth | Layers Involved | Appearance | Sensation | Healing | Treatment |
|-------|----------------|------------|-----------|---------|-----------|
| Superficial (1st degree) | Epidermis only | Erythema, no blisters | Painful | 3-5 days, no scarring | Supportive (NOT included in TBSA) |
| Superficial partial (2nd — superficial) | Epidermis + papillary dermis | Moist, pink, blisters | Painful, blanches | 7-14 days, minimal scarring | Wound care, rarely grafting |
| Deep partial (2nd — deep) | Epidermis + reticular dermis | Mottled pink/white | Decreased | 3-6 weeks, significant scarring | Often excision and grafting |
| Full thickness (3rd degree) | Entire dermis into subQ fat | Leathery, waxy white/brown/black | Painless | Cannot re-epithelialize | Excision and grafting required |
| Fourth degree | Muscle, tendon, bone | Charred, exposed deep structures | Absent | N/A | Flap, amputation, complex reconstruction |

### Superficial (First Degree)
Epidermis only. Erythema, pain, no blisters. Example: sunburn. Heals in 3-5 days without scarring. NOT included in TBSA calculation.

### Superficial Partial Thickness (Second Degree — Superficial)
Epidermis and superficial dermis (papillary dermis). Moist, pink, painful, blisters. Blanches with pressure; intact sensation. Heals in 7-14 days with minimal scarring. Rarely requires grafting.

### Deep Partial Thickness (Second Degree — Deep)
Epidermis and deep dermis (reticular dermis). Mottled pink/white, decreased sensation, less painful than superficial partial. Sluggish capillary refill. Heals in 3-6 weeks with significant scarring and contracture risk. Often requires excision and grafting for optimal outcomes.

### Full Thickness (Third Degree)
Through entire dermis into subcutaneous fat. Leathery, waxy white/brown/black, painless (nerve destruction), no blanching. Cannot heal by re-epithelialization (no dermal appendages remain). Requires excision and grafting.

### Fourth Degree
Extension into deep structures: muscle, tendon, bone. Often associated with electrical burns, prolonged contact burns. May require amputation or complex reconstruction.

## Fluid Resuscitation

### Parkland Formula (Modified Brooke)
**4 mL x body weight (kg) x %TBSA** burned = total crystalloid volume for first 24 hours. Use Lactated Ringer's solution. First half given in the first 8 hours from time of injury (not from time of presentation). Second half given over the next 16 hours.

Adjusted to maintain urine output: Adults: 0.5-1.0 mL/kg/hr. Children: 1.0-1.5 mL/kg/hr. Electrical burns: 1.0-1.5 mL/kg/hr (higher output to prevent myoglobin renal injury).

### Modified Brooke Formula
2 mL x kg x %TBSA for first 24 hours. Lower initial volume; titrated upward to urine output. Some centers prefer this to reduce fluid creep.

### Fluid Creep
Excessive fluid administration beyond calculated requirements. Causes: liberal urine output targets, failure to titrate, overestimation of TBSA. Consequences: compartment syndrome (abdominal, extremity, orbital), pulmonary edema, cerebral edema. Prevention: strict urine output titration; colloid (albumin 5%) added at 12-24 hours may reduce total crystalloid requirement. **Abdominal compartment syndrome**: bladder pressures >25 mmHg; may require decompressive laparotomy.

### Colloids
Albumin 5%: commonly added after 12-24 hours to reduce crystalloid requirements. Fresh frozen plasma: some centers use in severe burns. Role of colloids in the first 24 hours: controversial; most guidelines recommend crystalloid-only initially.

### Children
Children <20 kg require maintenance fluids with dextrose IN ADDITION to resuscitation fluids (limited glycogen stores → hypoglycemia risk). Maintenance: D5 0.45% NS at standard pediatric rates + Parkland formula with LR.

## Escharotomy

### Indications
Circumferential full-thickness burns of the extremities, chest, or abdomen causing: Vascular compromise (absent/diminished distal pulses, decreased capillary refill, cyanosis). Respiratory compromise (decreased chest wall compliance, elevated peak airway pressures). Compartment syndrome.

### Technique
Performed at bedside, no anesthesia needed for full-thickness burns (insensate tissue). Incision through the eschar into the subcutaneous fat (not into muscle fascia — that is fasciotomy). **Upper extremity**: medial and lateral incisions along the mid-axial line; extend across joints. **Lower extremity**: medial and lateral incisions; medial incision avoids the saphenous vein.

**Chest**: bilateral anterior axillary line incisions connected by a transverse subcostal incision (creates a "box" pattern). **Hand**: dorsal incisions in the intermetacarpal spaces; may include digital incisions if digits involved. Monitor for restoration of perfusion after release.

### Fasciotomy
If escharotomy is insufficient (persistent compartment syndrome). Full fasciotomy through the investing fascia releasing all compartments. May be needed in electrical burns (deep muscle injury).

<image>Anatomical illustration showing escharotomy incision sites on a full-body diagram of a burn patient with circumferential burns. The anterior view shows bilateral anterior axillary line chest escharotomies connected by a transverse subcostal incision. On the upper extremities, medial and lateral mid-axial line incisions extend from the arm through the elbow to the forearm, with the hand showing dorsal intermetacarpal incisions. On the lower extremities, medial and lateral mid-axial line incisions are shown from the thigh through the knee to the leg. Inset panels show the cross-sectional depth of the escharotomy incision — through the eschar into subcutaneous fat but NOT into the muscle fascia, with the fascia layer clearly labeled as the boundary. Color-coded labels identify each incision and its anatomical landmarks.</image>

## Transfer Criteria to Burn Center (ABA Guidelines)
Partial-thickness burns >10% TBSA. Burns involving face, hands, feet, genitalia, perineum, major joints. Full-thickness (third-degree) burns of any size. Electrical burns (including lightning).

Chemical burns. Inhalation injury. Burns in patients with significant comorbidities. Burns with associated trauma (if burn is the greater risk).

Burns in children (hospitals without pediatric burn expertise). Burns requiring special social, emotional, or rehabilitative intervention.

## Adjunctive Measures
Tetanus prophylaxis: update if not current. Nasogastric tube: for burns >20% TBSA (ileus prevention, gastric decompression). Foley catheter: mandatory for monitoring urine output in major burns. Pain management: IV opioids titrated; avoid IM (unpredictable absorption with edema).

Temperature management: maintain warm environment (thermoregulatory dysfunction). Early enteral nutrition: begin within 6-12 hours if possible (reduces hypermetabolic response, maintains gut mucosal integrity). DVT prophylaxis. Stress ulcer prophylaxis (Curling's ulcer prevention).

## Clinical Pearls
When in doubt about the airway, intubate early — waiting for overt stridor in a burn patient is waiting too long; airway edema peaks at 12-24 hours during fluid resuscitation and can render intubation impossible. Pulse oximetry is unreliable in CO poisoning (reads COHb as oxyhemoglobin); always obtain a co-oximetry panel and treat with 100% FiO2. TBSA estimation accuracy directly impacts resuscitation quality; use the Lund-Browder chart rather than the Rule of Nines, and remember that only partial- and full-thickness burns count toward TBSA.

Fluid creep is a real and dangerous phenomenon; strict urine output titration (not exceeding 1 mL/kg/hr) is the best safeguard — more fluid is not always better. Escharotomy is a bedside procedure that can be limb- and life-saving; do not wait for vascular surgery consultation — plastic surgery and burn surgery trainees must be proficient in this skill. Early enteral feeding within the first 6-12 hours significantly reduces the hypermetabolic response and improves outcomes in major burns.

## References
- American Burn Association. Advanced Burn Life Support Course Provider Manual. 2018.
- Pham TN, Cancio LC, Gibran NS. American Burn Association practice guidelines burn shock resuscitation. J Burn Care Res. 2008;29(1):257-266.
- Saffle JR. The phenomenon of "fluid creep" in acute burn resuscitation. J Burn Care Res. 2007;28(3):382-395.
- Herndon DN. Total Burn Care. 5th ed. Elsevier; 2018.
- Jeschke MG, van Baar ME, Choudhry MA, et al. Burn injury. Nat Rev Dis Primers. 2020;6(1):11.
- Baxter CR, Shires T. Physiological response to crystalloid resuscitation of severe burns. Ann N Y Acad Sci. 1968;150(3):874-894.