Burns Flashcards
What are the three types of burns, their mechanisms, and factors influencing severity?
Thermal Burns:
- Caused by direct or indirect contact with flame, hot liquids, or steam.
- Severity depends on contact time, temperature, and type of insult.
Chemical Burns:
- Result from acids, bases, or industrial chemicals.
- Alkaline burns are more severe than acidic burns.
- Severity depends on chemical concentration, contact time, and thoroughness of irrigation.
Electrical Burns:
- Caused by low- or high-voltage currents.
- Characterized by entrance and exit wounds, with deeper tissue damage due to varying tissue resistance.
- Severity depends on voltage, contact time, and whether the current is alternating (more damaging).
How do thermal, chemical, and electrical burns differ in presentation and long-term implications?
Thermal Burns:
- Present with localized tissue damage, varying in depth depending on contact time.
- Long-term complications include scarring and potential contractures.
Chemical Burns:
- Can worsen over time (24–72 hours) if not thoroughly irrigated.
- Long-term risks include full-thickness damage and systemic absorption of chemicals.
Electrical Burns:
- May have minimal visible skin damage despite severe internal injuries like muscle necrosis and cardiac arrhythmias.
- Long-term risks include nerve damage and organ failure.
Differentiate between superficial, partial-thickness, full-thickness, and subdermal burns.
Superficial Burns (1st degree):
- Affect the epidermis only.
- Skin is dry, red/pink, blanches under pressure, no blisters.
- Heals in 3–5 days without scarring (e.g., sunburn).
Partial-Thickness Burns (2nd degree):
- 1. Superficial:
- Involves the papillary dermis.
- Skin is moist, blistered, painful, and erythematous.
- Heals in 10–14 days with minimal scarring.
- 2. Deep:
- Extends to the reticular dermis.
- Skin is mottled red/white with eschar, slow capillary refill, and reduced sensation.
- Healing >3 weeks with risk of scarring and contractures.
Full-Thickness Burns (3rd degree):
- Destruction of epidermis and dermis to subcutaneous fat.
- Skin appears leathery, dry, insensate. Requires grafting.
Subdermal Burns (4th degree):
- Extends to muscle/bone.
- Charred appearance, insensate, often requires amputation.
What are common causes for each burn depth?
Superficial Burns:
- Sunburn, minor flash burns.
Partial-Thickness Burns:
- Superficial
- brief contact with hot objects or dilute chemicals;
- Deep
- prolonged contact with scalds or flames. Full-
Thickness Burns:
- Prolonged exposure to flame, immersion scalds.
Subdermal Burns:
- High-voltage electrical burns, strong chemical burns.
How do partial-thickness burns differ from full-thickness burns in healing and outcomes?
Partial-Thickness Burns:
- Heal through re-epithelialization.
- Superficial types heal within 10–14 days.
- Deep burns may take >3 weeks and carry risks of pigment changes and contractures.
Full-Thickness Burns:
- Require surgical intervention (debridement and grafting) as they lack viable epithelial structures for natural healing.
- Scarring and functional impairments are common without treatment.
What is the Rule of Nines, and how is it used in burn size estimation?
The Rule of Nines divides the body into regions representing 9% (or multiples) of the total body surface area (TBSA):
- Head (9%)
- Front and back of each arm (4.5%),
- Front of each leg (9%)
- Back of each leg (9%)
- Anterior trunk (18%)
- Posterior trunk (18%)
- Perineum (1%)
It provides a quick method for estimating burn size in adults but often overestimates injuries.
How does the Lund-Browder classification improve burn size estimation in children?
The Lund-Browder Classification adjusts for age-related differences in body proportions.
- For example, the head represents a larger percentage of TBSA in children.
- This method is more accurate for pediatric burn patients and is preferred in pediatric burn units.
What is the Palmar Method, and when is it used for burn size estimation?
- The Palmar Method uses the patient’s palm and fingers as a reference for estimating burn size, with the area representing approximately 1% of TBSA.
- It is particularly useful for assessing small, irregularly shaped burns when other methods are impractical.
How is burn severity classified, and what determines treatment location?
Burn severity depends on burn size, depth, and patient age:
- Minor Burns:
- Small partial-thickness burns (< 10% TBSA in adults, < 5% TBSA in children).
- Treated outpatient.
- Moderate Burns:
- Larger partial-thickness burns (10–20% TBSA in adults).
- Require inpatient care.
- Major Burns:
- > 20% TBSA in adults, full-thickness burns >10%, or burns involving critical areas (face, hands, feet, perineum).
- Treated in specialized burn centers.
What are the zones of burn injury, and how do they differ?
Burns involve three zones:
- Zone of Coagulation:
- Central area with irreparable damage and necrosis.
- Zone of Stasis:
- Surrounding area with impaired perfusion.
- Conversion can extend necrosis.
- Zone of Hyperemia:
- Peripheral area with minimal cellular damage, recoverable with proper treatment.
These zones guide therapeutic focus to prevent progression and promote healing.
What is burn shock, and why is fluid resuscitation critical in burn management?
- Burn shock is a condition of hypovolemia and edema caused by massive fluid shifts after burns >15% TBSA.
- It leads to reduced tissue perfusion, organ failure, and death if untreated.
- Fluid resuscitation using formulas like Parkland (e.g., 4 mL/kg/%TBSA) restores circulatory volume, prevents ischemia, and reduces complications.
- Blood pressure and heart rate (elevated to 100–120 bpm) must be monitored.
How do burns affect the pulmonary system, and what are key considerations for management?
- Burns may cause pulmonary damage, especially if inhalation injury is suspected (e.g., singed nasal hairs, carbonaceous sputum).
- Complications include airway obstruction, carbon monoxide poisoning, and ARDS.
- Management involves monitoring oxygen saturation, encouraging pulmonary hygiene (deep breathing, coughing), and possibly ventilatory support.
What metabolic changes occur after a major burn injury?
- Burns increase basal metabolic rate (BMR) up to 2–3 times normal levels, leading to hypercatabolism, muscle wasting, and stress hyperglycemia.
- Nutritional needs increase significantly, and core body temperature rises.
- These changes peak 7–17 days post-injury, requiring aggressive nutritional support to prevent loss of lean body mass and promote healing.
Why are burn patients at high risk for infection, and what are common signs?
- Burn patients are at high risk due to prolonged open wounds, decreased tissue perfusion, and ineffective neutrophils.
- Eschar and residual fluids provide an ideal environment for bacteria.
- Common signs of infection include increased erythema, pain, foul odor, purulence, necrosis, fever, and tachycardia.
What are the primary goals of debridement in burn wound management?
- Debridement removes necrotic tissue, exudate, and foreign debris to reduce infection risk, promote healing, and prepare for grafting.
- It may involve sharp, enzymatic, or mechanical techniques.
- Removal of blisters (open and closed) prevents bacterial colonization.
- Aggressive debridement is essential for large burns to ensure rapid coverage and minimize complications.