21.2 Burn Assessment, Inhalation Injury & Resuscitation

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20 Chapter 20: Acute Pulmonary & Airway Emergencies

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21 Chapter 21: Acute Traumatic Injuries & Wound Care

21.1 Major Trauma Resuscitation & Initial Assessment 21.2 Burn Assessment, Inhalation Injury & Resuscitation 21.3 Laceration Management, Complex Wounds & Animal Bites

22 Chapter 22: Acute Orthopedic & Musculoskeletal Emergencies

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23 Chapter 23: Severe Infections, Sepsis & Systemic Emergencies

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24 Chapter 24: Metabolic, Endocrine & Electrolyte Emergencies

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37 Chapter 37: Acute Abdominal Wall, Hernias & Dental Conditions

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38 Chapter 38: Acute Infectious Dermatoses

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40 Chapter 40: Acute Shoulder, Elbow & Upper Extremity Injuries

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41 Chapter 41: Acute Knee, Ankle & Lower Extremity Injuries

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42 Chapter 42: Acute Ambulatory Fractures & Dislocations

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43 Chapter 43: Acute Axial Musculoskeletal Pain & Falls

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44 Chapter 44: Acute Inflammatory Arthropathies & Generalized Pain

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46 Chapter 46: Acute Male Genitourinary & Prostatic Conditions

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48 Chapter 48: Breast Disorders, STIs & Pediatric Elimination

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49 Chapter 49: Systemic Signs, Metabolic Dysregulation & Miscellaneous Infections

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50 Chapter 50: Chronic Cardiovascular Diseases: Hypertension & Ischemia

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53 Chapter 53: Chronic Metabolic Diseases: Diabetes Mellitus

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57 Chapter 57: Chronic Gastrointestinal & Hepatic Diseases

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58 Chapter 58: Colorectal Surveillance & Chronic Pancreaticobiliary Care

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59 Chapter 59: Chronic Musculoskeletal & Rheumatologic Disorders

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60 Chapter 60: Chronic Neurologic & Neurodegenerative Disorders

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61 Chapter 61: Chronic Peripheral Nerves, Pain & Sensory Disorders

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62 Chapter 62: Chronic Psychiatric Disorders

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64 Chapter 64: Chronic Substance Use Disorders & Tobacco Cessation

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67 Chapter 67: Continuity Care: Sleep, Fatigue, Cancer, Pregnancy & the Adult Preventive Visit

67.1 Chronic Insomnia & Obstructive Sleep Apnea 67.2 Chronic Malaise, Fatigue & ME/CFS 67.3 Primary Care During Cancer Treatment & Survivorship 67.4 Routine Prenatal Care & Longitudinal Pregnancy Management 67.5 The Periodic Adult Health Examination & Medicare Annual Wellness Visit

21.2 Burn Assessment, Inhalation Injury & Resuscitation

Key Takeaways Explain This Topic AI

Burn depth is classified into first-degree (superficial: epidermis only, painful erythema without blisters, strictly excluded from TBSA calculations), second-degree superficial partial-thickness (blisters, weeping, exquisite pain, rapid blanching), second-degree deep partial-thickness (mottled white/pink, diminished sensation, slow blanching, high scarring risk), and third-degree full-thickness (leathery, charred or waxy white eschar, insensate to pinprick, non-blanching, requires excision and grafting).

The Parkland (Baxter) formula calculates 24-hour fluid resuscitation as 4 mL × body weight (kg) × %TBSA of partial- and full-thickness burns, administered as Lactated Ringer's; 50% must be infused within the first 8 hours from the moment of burn injury (not hospital arrival), and 50% over the subsequent 16 hours, dynamically titrated to target an adult urine output of 0.5–1.0 mL/kg/hour.

Inhalation injury presents with facial burns, singed nasal vibrissae, carbonaceous sputum, and inspiratory stridor, mandating proactive, early endotracheal intubation before progressive glottic and laryngeal edema completely obstructs the airway over 12 to 24 hours.

Carbon monoxide (CO) poisoning produces falsely normal pulse oximetry readings and requires arterial/venous co-oximetry and immediate 100% normobaric oxygen (hyperbaric oxygen indicated for COHb >25%, pregnancy >15%, loss of consciousness, or ischemic signs); severe metabolic lactic acidosis (>8–10 mmol/L) in closed-space fire victims indicates hydrogen cyanide toxicity requiring intravenous hydroxocobalamin.

Circumferential full-thickness burns of the chest compromise ventilatory compliance, while circumferential extremity burns threaten limb viability via compartment syndrome, requiring emergency longitudinal surgical escharotomy through the full thickness of the eschar into subcutaneous tissue.

Last updated: September 2026

Pathophysiology of Thermal Injury & Burn Depth Classification

Severe thermal burns induce both localized tissue coagulation and a massive systemic inflammatory response. In burns exceeding 20 % 20\% 20% Total Body Surface Area (TBSA), widespread release of vasoactive mediators (histamine, bradykinin, prostaglandins, thromboxane A 2 A_2 A 2 ​ , tumor necrosis factor-alpha) triggers extensive capillary endothelial hyperpermeability, profound plasma extravasation into the interstitial third-space, and systemic hypovolemic/distributive burn shock .

Jackson's Burn Wound Model

Locally, thermal injury organizes into three distinct concentric histological zones:

Zone of Coagulation : The central area of maximal thermal contact. Complete cellular necrosis and microvascular thrombosis occur instantaneously. This tissue is nonviable and forms the avascular eschar requiring surgical debridement.

Zone of Stasis : The intermediate zone surrounding the central coagulation zone. Characterized by compromised microvascular perfusion, cellular ischemia, and endothelial swelling. This zone is potentially salvageable with aggressive, timely fluid resuscitation and avoidance of hypothermia. Inadequate resuscitation converts the zone of stasis into nonviable coagulation necrosis ("burn wound conversion").

Zone of Hyperemia : The outermost peripheral zone. Exhibits prominent vasodilation and increased blood flow secondary to local inflammatory mediator release. This tissue uniformly recovers viability within 7 to 10 days unless complicated by invasive secondary infection. JACKSON'S CONCENTRIC ZONES OF BURN INJURY

• ┌────────────────────────────────────────────────────────┐
• │ ZONE OF HYPEREMIA (Outermost) │
• │ • Marked vasodilation & inflammatory hyperemia │
• │ • Fully viable tissue; heals spontaneously │
• │ ┌────────────────────────────────────────────────┐ │
• │ │ ZONE OF STASIS (Intermediate) │ │
• │ │ • Ischemia, sluggish microvascular perfusion │ │
• │ │ • SALVAGEABLE with timely fluid resuscitation │ │
• │ │ • Converts to necrosis if hypoperfusion occurs │ │
• │ │ ┌────────────────────────────────────────┐ │ │
• │ │ │ ZONE OF COAGULATION (Central) │ │ │
• │ │ │ • Irreversible tissue necrosis │ │ │
• │ │ │ • Thrombosed microvessels; eschar │ │ │
• │ │ │ • Requires excision and skin grafting │ │ │
• │ │ └────────────────────────────────────────┘ │ │
• │ └────────────────────────────────────────────────┘ │
• └────────────────────────────────────────────────────────┘
• Clinical Classification of Burn Depth

Burn Degree & Depth Anatomical Layer Involved Clinical Appearance & Texture Sensation & Capillary Blanching Healing Time & Prognosis

First-Degree (Superficial) Epidermis only (basal layer intact) Bright erythematous, dry, NO blisters or bullae ; smooth Exquisitely painful, hyperesthetic; blanches briskly with light pressure Heals in 3 to 6 days by desquamation; no scarring ; (e.g., standard sunburn). EXCLUDED from %TBSA calculations.

Second-Degree (Superficial Partial-Thickness) Epidermis and upper papillary dermis Erythematous or pink, moist, weeping, thin-walled blisters ; serous exudate Intensely painful; exquisitely tender to touch and air currents; rapid capillary blanching Heals in 7 to 21 days via re-epithelialization from hair follicles; minimal hypertrophic scar risk; pigment changes possible.

Second-Degree (Deep Partial-Thickness) Extends into the deep reticular dermis Mottled white to patchy pink, dry or waxy, ruptured thick-walled blisters Diminished light touch sensation; dull aching pressure intact; sluggish or absent blanching Takes >3 to 4 weeks ; high risk of contractures and hypertrophic scarring; frequently warrants surgical excision and grafting.

Third-Degree (Full-Thickness) Entire epidermis and entire dermis destroyed into subcutaneous fat Hard, leathery, rigid, dry eschar ; translucent waxy white, mahogany brown, or charred black; thrombosed visible veins Anesthetic and insensate to light touch and pinprick (nerve endings destroyed); non-blanching Does NOT heal spontaneously (except small defects < 2 cm <2\text{ cm} < 2 cm by severe contracture); requires surgical debridement and split-thickness skin grafting .

Fourth-Degree Destroys all skin, subcutaneous tissue, down into fascia, muscle, tendon, and bone Black, charred, skeletonized, dry, cracked tissue Complete anesthesia Devastating injury; requires extensive radical surgical debridement, tissue flaps, or amputation ; high mortality.

Total Body Surface Area (%TBSA) Calculation

Accurate calculation of the burned Total Body Surface Area (%TBSA) is essential to determine fluid resuscitation volumes and assess burn center transfer criteria. Overestimating %TBSA leads to fluid overload, while underestimating causes acute tubular necrosis and burn shock.

The Adult Rule of Nines

The adult body is divided into anatomical regions representing multiples of 9 % 9\% 9% :

Head and Neck : 9 % 9\% 9% (entire anterior face/neck 4.5 % 4.5\% 4.5% , entire posterior head/neck 4.5 % 4.5\% 4.5% )

• Anterior Torso (Chest and Abdomen) : 18 % 18\% 18%
• Posterior Torso (Upper and Lower Back) : 18 % 18\% 18%

Each Upper Extremity : 9 % 9\% 9% (entire right arm 9 % 9\% 9% , entire left arm 9 % 9\% 9% ; anterior 4.5 % 4.5\% 4.5% , posterior 4.5 % 4.5\% 4.5% each)

Each Lower Extremity : 18 % 18\% 18% (entire right leg 18 % 18\% 18% , entire left leg 18 % 18\% 18% ; anterior 9 % 9\% 9% , posterior 9 % 9\% 9% each)

• Perineum and External Genitalia : 1 % 1\% 1%
• The Palmar Method

For scattered, patchy, or irregular burns, the patient's palmar surface (including the palm and all five extended fingers) equals approximately 1 % 1\% 1% of their Total Body Surface Area . Clinicians assess how many "patient palms" are required to cover the burned patches.

Important

THE GOLDEN RULE OF TBSA CALCULATION: First-degree burns (superficial erythema without blisters, such as sunburn) are STRICTLY EXCLUDED from %TBSA calculations. Only partial-thickness (second-degree) and full-thickness (third-degree) burns are included in fluid calculations. Counting superficial erythema results in severe fluid over-resuscitation ("fluid creep"), causing abdominal compartment syndrome and acute pulmonary edema.

Pediatric Differences: The Lund-Browder Chart

Children have a dramatically larger head-to-body surface area ratio and smaller lower extremities than adults. Using the adult Rule of Nines in infants causes gross estimation errors. Under the Lund-Browder Chart :

In an infant, the head accounts for 18 % 18\% 18% of TBSA, while each leg accounts for only 14 % 14\% 14% .

For every year of age past 1 year, the head decreases by 1 % 1\% 1% while each lower extremity increases by 0.5 % 0.5\% 0.5% , until adult proportions are attained at approximately 10 years of age.

Fluid Resuscitation: The Parkland (Baxter) Formula

Formal intravenous fluid resuscitation is indicated for all adult patients with partial- and full-thickness burns involving ≥ 20 % \ge 20\% ≥ 20% TBSA (or ≥ 10 % \ge 10\% ≥ 10% TBSA in pediatric patients ).

The 24-Hour Formula Total 24-Hour Crystalloid Volume = 4 mL × Body Weight (kg) × % TBSA (2nd and 3rd degree burns only) \text{Total 24-Hour Crystalloid Volume} = 4\text{ mL} \times \text{Body Weight (kg)} \times \%\text{TBSA (2nd and 3rd degree burns only)} Total 24-Hour Crystalloid Volume = 4 mL × Body Weight (kg) × % TBSA (2nd and 3rd degree burns only)

Fluid of Choice : Lactated Ringer's (LR) solution. Balanced crystalloid solutions match physiological electrolyte osmolarity and provide sodium lactate buffers. Normal saline ( 0.9 % NaCl 0.9\%\text{ NaCl} 0.9% NaCl ) is avoided in massive resuscitation because its high chloride concentration ( 154 mEq/L 154\text{ mEq/L} 154 mEq/L ) induces severe hyperchloremic non-anion gap metabolic acidosis and impairs renal perfusion.

The Two-Interval Administration Schedule :

First 8 Hours : Administer 50 % 50\% 50% of the total calculated volume within the first 8 hours FROM THE EXACT TIME OF THE BURN INJURY (NOT from the time of hospital arrival!). Any intravenous fluid already administered by EMS or referring clinics is subtracted from this 8-hour total.

Next 16 Hours : Administer the remaining 50 % 50\% 50% of the calculated volume evenly over the subsequent 16 hours.

Clinical Example of Resuscitation Timing

Scenario : A 75-kg male sustains 30 % 30\% 30% TBSA partial- and full-thickness burns at 12:00 PM. He arrives in the emergency department at 2:00 PM (2 hours post-injury) having received 500 mL 500\text{ mL} 500 mL LR en route.

Calculation :

Total 24-hour volume = 4 mL × 75 kg × 30 = 9 , 000 mL = 4\text{ mL} \times 75\text{ kg} \times 30 = 9,000\text{ mL} = 4 mL × 75 kg × 30 = 9 , 000 mL LR.

First 8-hour requirement = 50 % of 9 , 000 mL = 4 , 500 mL = 50\% \text{ of } 9,000\text{ mL} = 4,500\text{ mL} = 50% of 9 , 000 mL = 4 , 500 mL .

This 4 , 500 mL 4,500\text{ mL} 4 , 500 mL must be completed by 8:00 PM (8 hours post-injury).

Since 2 hours have already elapsed and 500 mL 500\text{ mL} 500 mL was infused, the patient requires 4 , 500 − 500 = 4 , 000 mL 4,500 - 500 = 4,000\text{ mL} 4 , 500 − 500 = 4 , 000 mL over the remaining 6 hours.

Initial infusion rate = 4 , 000 mL / 6 hours = 667 mL/hour = 4,000\text{ mL} / 6\text{ hours} = 667\text{ mL/hour} = 4 , 000 mL /6 hours = 667 mL/hour .

The remaining 4 , 500 mL 4,500\text{ mL} 4 , 500 mL is infused over the subsequent 16 hours ( 281 mL/hour 281\text{ mL/hour} 281 mL/hour ).

Clinical Monitoring & Dynamic Titration

The Parkland formula is merely a starting guide. Fluid infusion rates must be titrated up or down hourly by 10 % to 20 % 10\%\text{ to }20\% 10% to 20% based on objective physiological endpoints:

Adult Target Urine Output : 0.5 to 1.0 mL/kg/hour 0.5\text{ to }1.0\text{ mL/kg/hour} 0.5 to 1.0 mL/kg/hour (approximately 30 to 50 mL/hour 30\text{ to }50\text{ mL/hour} 30 to 50 mL/hour in an average adult).

Pediatric Target Urine Output : 1.0 to 2.0 mL/kg/hour 1.0\text{ to }2.0\text{ mL/kg/hour} 1.0 to 2.0 mL/kg/hour (in children weighing < 30 kg <30\text{ kg} < 30 kg ).

High-Voltage Electrical Burns & Crush Injuries : Extensive deep muscle necrosis releases massive amounts of myoglobin and potassium into the circulation. To prevent myoglobin cast precipitation and acute tubular necrosis, target an adult urine output of 1.5 to 2.0 mL/kg/hour 1.5\text{ to }2.0\text{ mL/kg/hour} 1.5 to 2.0 mL/kg/hour ( 75 to 100 mL/hour 75\text{ to }100\text{ mL/hour} 75 to 100 mL/hour ) until urine is visibly clear of pigment, and administer IV sodium bicarbonate to alkalinize the urine (target urine p H > 6.5 pH > 6.5 p H > 6.5 ).

Danger of "Fluid Creep" : Excessive over-resuscitation beyond target urine outputs drives fluid into non-burned tissues, precipitating life-threatening abdominal compartment syndrome (intra-abdominal pressure > 20 mmHg >20\text{ mmHg} > 20 mmHg ) , severe extremity compartment syndrome, ocular compartment syndrome, and acute respiratory failure.

Upper Airway Inhalation Injury & Airway Protection

Inhalation injury is the single most important predictor of burn mortality, increasing the expected mortality of any given burn by > 20 % >20\% > 20% . Injury occurs along two distinct anatomical segments:

Supraglottic Upper Airway Thermal Injury : Direct heat transfer to the nasopharynx, epiglottis, and vocal cords. True thermal burns rarely penetrate below the vocal cords because the upper airway acts as an efficient heat exchanger, rapidly cooling superheated air.

Subglottic Lower Airway Chemical Tracheobronchitis : Inhalation of toxic smoke particulates, aldehydes, sulfur dioxide, and acid fumes causes chemical injury to bronchiolar epithelium, ciliary paralysis, mucosal sloughing, airway casting, and severe bronchospasm.

Clinical Signs Demanding Immediate Proactive Intubation

Progressive glottic, pharyngeal, and aryepiglottic edema develops rapidly over the first 12 to 24 hours post-injury as fluid resuscitation expands third-spaced interstitial tissues. Clinicians must maintain a low threshold for early preemptive endotracheal intubation when signs of upper airway burn are present:

• History of fire trapped within a closed, enclosed space;
• Deep facial, perioral, or neck burns;
• Singed nasal vibrissae (hairs) and singed eyebrows;
• Soot deposits in the oral cavity, palate, posterior pharynx, or tongue ;
• Carbonaceous (soot-laden) sputum ;
• Development of hoarseness, brassy cough, or deep phonation changes ;

Inspiratory stridor, tachypnea, or intercostal retractions (indicates > 85 % >85\% > 85% airway lumen occlusion).

Warning

THE INHALATION AIRWAY TRAP: In an acute burn patient with perioral soot and mild hoarseness, oxygen saturation may remain completely normal ( 98 % to 100 % 98\%\text{ to }100\% 98% to 100% ) during the first few hours. Do not be falsely reassured by a normal pulse oximetry reading or clear lung auscultation. Attempting endotracheal intubation 8 to 12 hours later, when massive supraglottic edema has converted the vocal cords into an unrecognizable mass of swollen gelatinous tissue, frequently results in a catastrophic "cannot intubate, cannot ventilate" scenario requiring emergency surgical cricothyroidotomy.

Toxic Inhalation Syndromes: Carbon Monoxide & Cyanide

Patients rescued from enclosed structural fires frequently suffer from toxic asphyxiant inhalations that prevent cellular ATP generation: TOXIC INHALATION RESUSCITATION PATHWAY

• Victim Rescued from Enclosed Space Fire
• │
• 100% Normobaric Oxygen via NRB
• │
• ┌───────────────────────┴───────────────────────┐
• ▼ ▼
• CARBON MONOXIDE (CO) HYDROGEN CYANIDE (HCN)
• Affinity 200x > Oxygen • Inhibits Cytochrome c Oxidase
• SpO2 falsely reads 100% • Profound Cellular Dysoxia
• Send Blood Co-Oximetry (COHb) • Severe Lactic Acidosis (>8-10 mmol/L)
• │ │
• ┌───────┴───────┐ ▼
• ▼ ▼ INTRAVENOUS HYDROXOCOBALAMIN
• COHb <25% COHb >25% (5g IV Cyanokit over 15 min)
• (No signs) (or >15% Pregnant, • Binds CN -> Cyanocobalamin
• │ Coma, Ischemia) • Excreted harmlessly in urine
• ▼ │
• Continue ▼
• 100% O2 HYPERBARIC OXYGEN
• (until THERAPY (HBO)
• COHb <5%) (Reduces half-life
• to ~20-30 min)
• 1. Carbon Monoxide (CO) Poisoning

Mechanism : Carbon monoxide binds hemoglobin with an affinity 200 to 250 times greater than oxygen , forming carboxyhemoglobin (COHb). This directly displaces oxygen from binding sites and shifts the oxyhemoglobin dissociation curve sharply to the left (Haldane effect), preventing oxygen release to peripheral tissues. CO also binds intracellular myoglobin and mitochondrial cytochrome oxidase, halting ATP production.

The Pulse Oximetry Fallacy : Standard two-wavelength pulse oximeters measure light absorbance at 660 nm and 940 nm, cannot distinguish carboxyhemoglobin from oxyhemoglobin, and falsely report normal or near-normal values ( 99 % to 100 % 99\%\text{ to }100\% 99% to 100% ) . Clinicians must obtain an arterial or venous blood gas with co-oximetry to measure the carboxyhemoglobin level.

Treatment Protocol :

Administer 100 % 100\% 100% high-flow normobaric oxygen via a tight-fitting non-rebreather mask (or endotracheal tube). This accelerates CO dissociation from hemoglobin, reducing the half-life of COHb from 300 minutes on room air down to 60 to 90 minutes on 100 % O 2 100\%\text{ }O_2 100% O 2 ​ .

Indications for Hyperbaric Oxygen (HBO) Therapy :

Carboxyhemoglobin level > 25 % > 25\% > 25% in non-pregnant patients;

Carboxyhemoglobin level > 15 % > 15\% > 15% in pregnant women (fetal hemoglobin binds CO with higher affinity, and fetal tissue is uniquely vulnerable to hypoxic death);

• Any documented history of loss of consciousness, syncope, or seizure ;
• Unresolved neurological deficits, confusion, or severe delirium ;
• Evidence of acute myocardial ischemia (angina, ischemic ECG changes, or elevated troponin) ;

Severe refractory metabolic acidosis ( p H < 7.25 pH < 7.25 p H < 7.25 ).

HBO delivers 100 % O 2 100\%\text{ }O_2 100% O 2 ​ at 2.5 to 3 atmospheres absolute, reducing COHb half-life to 20 to 30 minutes and preventing delayed neuropsychiatric sequelae.

2. Hydrogen Cyanide (HCN) Poisoning

Mechanism : Generated during the incomplete combustion of nitrogen-containing synthetic materials, polyurethane foam, plastics, insulation, and synthetic carpets. Inhaled cyanide binds with high affinity to ferric iron ( F e 3 + Fe^{3+} F e 3 + ) within mitochondrial cytochrome c oxidase (Complex IV) of the electron transport chain. This completely halts oxidative phosphorylation, uncouples cellular respiration, and prevents cells from utilizing oxygen (histotoxic hypoxia), forcing anaerobic glycolysis.

Diagnostic Hallmarks :

The combination of soot in the pharynx and severe, refractory metabolic lactic acidosis (serum lactate > 8 to 10 mmol/L > 8\text{ to }10\text{ mmol/L} > 8 to 10 mmol/L ) in an enclosed-space fire victim is virtually diagnostic of cyanide poisoning.

Central venous oxygen saturation ( S c v O 2 ScvO_2 S c v O 2 ​ ) or mixed venous oxygen saturation is paradoxically elevated ( > 80 % to 85 % >80\%\text{ to }85\% > 80% to 85% ), reflecting inability of peripheral tissues to extract circulating oxygen.

Definitive Antidote: Hydroxocobalamin (Cyanokit) :

Administer 5 g 5\text{ g} 5 g IV infused over 15 minutes (pediatric dose 70 mg/kg 70\text{ mg/kg} 70 mg/kg ). A second 5 g 5\text{ g} 5 g dose can be repeated if hemodynamic instability or lactic acidosis persists.

Mechanism : Hydroxocobalamin contains cobalt that binds cyanide with higher affinity than cytochrome oxidase, forming non-toxic cyanocobalamin (vitamin B 12 B_{12} B 12 ​ ) , which is excreted safely in the urine.

Clinical Note : Causes transient reddish discoloration of the skin and dark red "burgundy" urine, and temporarily interferes with colorimetric laboratory assays (bilirubin, creatinine, co-oximetry).

Historical Warning : The traditional cyanide antidote kit containing sodium nitrite is avoided in burn patients because nitrites induce methemoglobinemia, which severely worsens oxygen-carrying capacity in patients with concurrent carbon monoxide poisoning.

Circumferential Burns & Emergency Escharotomy

Full-thickness third-degree burns produce rigid, inelastic, leathery eschar. During vigorous fluid resuscitation, progressive interstitial edema expands beneath the unyielding eschar, creating dangerous tourniquet and compartment syndromes :

Indications for Surgical Escharotomy

Circumferential Torso / Chest Burns :

Edema expanding against the rigid chest eschar severely restricts diaphragmatic descent and chest wall compliance.

Produces progressive hypoventilation, rapidly escalating peak airway pressures ( > 40 cm H 2 O >40\text{ cm }H_2O > 40 cm H 2 ​ O ) on the mechanical ventilator, refractory hypercapnia, and hypoxemia.

Circumferential Extremity Burns :

Intracompartmental tissue pressure escalates, exceeding capillary perfusion pressure ( > 30 mmHg >30\text{ mmHg} > 30 mmHg ). This compresses venous return, followed by arterial inflow, producing limb-threatening ischemic compartment syndrome.

Signs : Severe pain out of proportion (in partial-thickness borders), deep distal paresthesias, tense woody firmness, progressive pallor, delayed capillary refill ( > 3 seconds >3\text{ seconds} > 3 seconds ), and loss of distal arterial Doppler flow signals .

Procedural Technique of Bedside Escharotomy

Escharotomy is performed at the bedside under sterile conditions using an electrocautery unit or scalpel. Local anesthesia is generally unnecessary through third-degree full-thickness eschar (which is anesthetic).

Chest Incisions : Longitudinal bilateral incisions along the anterior axillary lines , joined across the lower rib margin by a transverse subcostal incision, creating a "U-shaped" release that frees the anterior thoracic plate.

Extremity Incisions : Longitudinal mid-lateral or mid-medial incisions along the anatomical neutral axes of the limb, extending across burned joints from non-burned tissue to non-burned tissue.

Depth of Incision : Incise only through the full thickness of the leathery eschar and superficial dermis until the subcutaneous fat pops open and herniates slightly outward. Do NOT incise the deep investing muscle fascia (fasciotomy is reserved for underlying high-voltage electrical injury or refractory compartment syndrome). Avoid major superficial nerves (ulnar nerve at the medial epicondyle; common peroneal nerve at the fibular head).

American Burn Association (ABA) Burn Center Transfer Criteria

Patients meeting any of the following criteria should be transferred to an accredited American Burn Association burn center following initial stabilization:

Partial-thickness (second-degree) burns involving > 10 % >10\% > 10% TBSA ;

Burns involving sensitive cosmetic or functional anatomical zones : the face, hands, feet, genitalia, perineum, or overlying major synovial joints;

• Third-degree (full-thickness) burns of any size in any age group ;
• Electrical burns , including high-voltage, low-voltage, and lightning strike injuries;
• Chemical burns from industrial acids, alkalis, or corrosive organics;
• Inhalation injury of any severity;

Burn injury in patients with preexisting medical disorders that could complicate management, prolong recovery, or affect mortality (e.g., severe heart failure, renal failure, cirrhosis);

Burn injury accompanied by concomitant traumatic mechanical injury (e.g., fractures) where the burn injury poses the greatest immediate risk of morbidity or mortality;

Burned children in hospitals without specialized pediatric personnel or equipment;

Burn injury requiring specialized social, emotional, or long-term rehabilitative intervention .

Loading diagram... Burn Resuscitation, Inhalation Assessment & Escharotomy Decision Flowchart