How are burns classified by depth, what are the characteristic clinical features of first‑, second‑ (superficial and deep partial‑thickness), third‑, and fourth‑degree burns, and what is the optimal management for each category?

Burn Classification and Management

Burn Classification by Depth

Burns are classified into four main categories based on depth of tissue injury: first-degree (superficial), second-degree (partial-thickness, subdivided into superficial and deep), third-degree (full-thickness), and fourth-degree (extending to deep structures), with each requiring progressively more aggressive management. 1, 2

First-Degree Burns (Superficial/Epidermal)

• Involve only the epidermis without destruction of skin appendages 1, 3
• Clinical features: Erythema, pain, intact skin without blistering 1
• Healing: Follow normal wound healing progression (inflammation, proliferation, remodeling) without scarring 1

Second-Degree Burns (Partial-Thickness)

Superficial Partial-Thickness (Superficial Dermal)

• Involve epidermis and superficial dermis with preserved skin appendages 1, 3
• Clinical features: Blistering, moist appearance, intense pain, blanching with pressure 1
• Healing: Progress through normal wound healing phases without requiring surgical intervention 1

Deep Partial-Thickness (Deep Dermal)

• Involve epidermis and deep dermis with destruction of most skin appendages 1, 3
• Clinical features: White or mottled appearance, decreased sensation, may not blanch 1
• Healing: Cannot heal optimally without intervention; severe scarring occurs if not excised and grafted 1, 2

Third-Degree Burns (Full-Thickness)

• Complete destruction of epidermis and dermis including all skin appendages 1, 2
• Clinical features: Leathery, white, brown, or charred appearance; painless due to nerve destruction; non-blanching 1, 2
• Healing: Require surgical excision and grafting for optimal coverage, function, and cosmesis 1, 2

Fourth-Degree Burns

• Extend beyond skin into deeply located soft tissues, potentially involving muscle, bone, and joints 3
• Clinical features: Charred appearance with visible deep structures 3
• Healing: Require extensive surgical debridement, possible amputation, and complex reconstruction 3

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Optimal Management by Burn Category

First-Degree and Superficial Partial-Thickness Burns

Immediate Cooling

• Cool immediately with clean running water (15-25°C) for 5-20 minutes as soon as possible after injury 4, 5
• Cooling is effective up to 3 hours post-injury and significantly reduces need for skin grafting when performed for 20-40 minutes 5
• Monitor preadolescent children for hypothermia during active cooling 4
• Do not cool if TBSA >20% in adults or >10% in children due to hypothermia risk 5, 6

Pain Management

• Administer over-the-counter analgesics (acetaminophen or NSAIDs) for pain control 4
• For more severe pain, use titrated intravenous opioids and ketamine guided by validated pain assessment scales 5, 7

Wound Care

• Clean with tap water, isotonic saline, or antiseptic solution in a clean environment 5, 6
• After cooling, apply petrolatum, petrolatum-based antibiotic ointment, medical-grade honey, or aloe vera with a clean nonadherent dressing 4, 5
• Moist dressings significantly reduce hypertrophic scarring compared to dry dressings 5, 6
• Avoid prolonged silver sulfadiazine use on superficial burns as it delays healing 5, 7

Infection Prevention

• Do not use topical antibiotics prophylactically; reserve for confirmed infections only 5, 6
• Monitor for infection signs: increasing pain, redness, swelling, purulent discharge 5, 6

Home Management Criteria

• Small partial-thickness burns without involvement of face, hands, feet, or genitals can be managed at home 4

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Deep Partial-Thickness Burns

Initial Assessment and Cooling

• Cool with clean running water (15-25°C) for up to 40 minutes if TBSA <20% in adults or <10% in children 5, 6
• Remove all contaminated clothing immediately to prevent continued injury 6

Pain Management

• Provide deep analgesia or general anesthesia for wound care procedures 5, 6
• Use titrated intravenous ketamine combined with opioids for severe pain 5, 7
• Short-acting opioids are most effective for dressing changes 7

Wound Care

• Clean thoroughly with tap water, isotonic saline, or antiseptic solution after adequate pain control 5, 6
• Apply moist dressings (petrolatum-based ointment, medical-grade honey, or aloe vera) with nonadherent secondary dressing 5, 6
• Re-evaluate dressings daily to detect early complications 5
• Prevent tourniquet effect when dressing limbs and monitor distal perfusion continuously 5

Surgical Intervention

• Deep partial-thickness burns require necrectomy and skin grafting to prevent severe scarring 1, 2
• Ideally consult a burn specialist before applying dressings to determine optimal approach 7

Burn Center Referral

• Refer all deep partial-thickness burns involving face, hands, feet, genitalia, or perineum regardless of size 4, 5, 6
• Refer if TBSA >10% in adults or >5% in children 4, 5, 6

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Third-Degree (Full-Thickness) Burns

Immediate Management

• Do not cool extensively if patient shows signs of shock or if burn is large 5, 6
• Remove jewelry immediately before swelling occurs to prevent vascular compromise 4

Pain Management

• Administer titrated intravenous ketamine combined with opioids using validated pain scales 5, 7
• Inhaled nitrous oxide can be used when IV access unavailable 5, 6

Fluid Resuscitation

• Initiate balanced crystalloid (Ringer's Lactate) at 20 mL/kg within first hour for burns >15% TBSA in adults or >10% in children 5
• Target urine output of 0.5-1 mL/kg/h as primary resuscitation endpoint 5

Wound Care

• Wound care is not a priority until after adequate resuscitation 7
• Clean with tap water, isotonic saline, or antiseptic solution after resuscitation 5, 6
• Apply moist dressings to protect from contamination and limit heat loss 5, 6

Surgical Management

• All full-thickness burns require early necrectomy and split-thickness skin grafting for optimal outcomes 1, 2, 8
• Early excision and grafting greatly improved survival rates and reduced sepsis-related mortality 8

Mandatory Burn Center Referral

• All full-thickness burns require burn center treatment regardless of size 4, 5, 6
• Contact burn specialist immediately to guide fluid resuscitation and determine transfer 5, 6
• Direct burn center admission (versus secondary transfer) is associated with improved survival, fewer complications, shorter hospital stays, and lower costs 5, 6

Escharotomy Considerations

• Perform escharotomy if deep circumferential burns cause compartment syndrome threatening limb perfusion or respiratory compromise 5, 7
• Assess for compartment syndrome: tightness, swelling, burning pain, distal neurovascular compromise 7
• Blue, purple, or pale extremities indicate poor perfusion requiring emergency escharotomy 7
• Escharotomies should ideally be performed at burn center; obtain specialist advice before proceeding if transfer not feasible 5

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Fourth-Degree Burns

Immediate Management

• Activate EMS immediately for all fourth-degree burns 4
• Do not attempt cooling due to extensive tissue damage and shock risk 5, 6

Pain Management

• Provide titrated intravenous ketamine and opioids or general anesthesia 5, 6, 7

Surgical Management

• Require extensive surgical debridement of all necrotic tissue including muscle and bone 3
• May require amputation if limb viability cannot be preserved 3
• Complex reconstruction with flaps or other advanced techniques needed 3

Mandatory Burn Center Referral

• All fourth-degree burns require immediate burn center transfer 5, 6
• Contact burn specialist immediately for guidance 5, 6

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Special Burn Types Requiring Immediate Recognition

Inhalation Injury

• Signs: Facial burns, difficulty breathing, singed nasal hairs, soot around nose/mouth, carbonaceous sputum 4, 9
• Activate EMS immediately as inhalation injury can rapidly cause airway loss and indicates possible carbon monoxide poisoning 4
• Requires burn center referral regardless of TBSA 5, 6

Electrical Burns

• Any electrical burn in children is automatically classified as severe 7
• High-voltage electrical burns in adults require burn center referral 7

Chemical Burns

• Require burn center referral regardless of size 7
• Thorough irrigation essential to remove all chemical agents 5

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Additional Supportive Care for Major Burns

Nutritional Support

• Initiate within 12 hours of injury, preferably via oral or enteral routes 5, 6
• Supplement with trace elements (copper, zinc, selenium) and vitamins (B-complex, C, D, E) 5, 6

Thromboprophylaxis

• Routinely prescribe for severe burn patients in initial phase 5, 6

Infection Prevention

• No systemic antibiotic prophylaxis routinely 5, 6
• Topical antibiotics reserved for confirmed infections only 5, 6
• Burn wounds are sterile immediately post-injury but rapidly colonized by Gram-positive bacteria, followed by Gram-negative within one week 6

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Critical Pitfalls to Avoid

• Never apply ice directly to burns – causes tissue ischemia and additional damage 5, 6
• Never use external cooling devices for prolonged periods – increases hypothermia risk in extensive burns 5, 6
• Never break blisters – increases infection risk 6
• Never apply butter, oil, or home remedies – increases infection risk and delays healing 6
• Never delay burn center transfer – direct admission yields better outcomes 5, 6
• Never over-resuscitate – monitor closely for fluid overload 5
• Never wait for pulse loss in suspected compartment syndrome – irreversible damage occurs within 6-8 hours 7
• Never use topical antibiotics prophylactically – promotes antimicrobial resistance 5, 6