Full-thickness burn
Depth of injury · All adnexa destroyed Insensate Graft essential
Destroys epidermis, the entire dermis and every adnexal structure, often reaching the hypodermis. With no surviving epithelial reservoir, the wound can only close by contraction and inward migration from its margin, so grafting is mandatory.
Traced from the start
Detail
- Depth destroyed
- Epidermis, full dermis and all hair follicles, sebaceous and sweat glands, extending into the subcutaneous fat
- Clinical signs
- Insensate to pinprick because the dermal nerve endings are destroyed, with no capillary refill and a leathery inelastic eschar
- Healing
- No re-epithelialisation is possible from within the wound; treatment is excision and split-thickness or full-thickness grafting
- Fourth degree
- Injury extending through the hypodermis into fascia, muscle or bone
- Physiological cost
- Loss of the barrier over a large area causes evaporative water loss, hypothermia, catabolism and a wide portal for Pseudomonas and Staphylococcus sepsis
When it goes wrong
Circumferential full-thickness burn of a limb or the chest
The inelastic eschar acts as a tourniquet: distal ischaemia with absent pulses on Doppler, or restricted chest expansion with rising airway pressures; the treatment is escharotomy
High-voltage electrical injury
Extensive deep muscle necrosis under deceptively small skin wounds, with rhabdomyolysis, myoglobinuric acute kidney injury and hyperkalaemia; give generous fluids targeting a higher urine output than the burn formula predicts
Chronic non-healing full-thickness burn scar or ulcer
Marjolin ulcer, an aggressive squamous cell carcinoma arising decades later in scar tissue
Practise this structure
16 questions in the bank tagged Skin.
A 45-year-old woman presents with a painful, swollen, red area on her right forearm that developed over the past two days. She reports a minor cut from gardenin…
Mechanisms of disease · common
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Mechanisms of disease · middle twist
A 65-year-old man presents with purple spots on his forearms and hands that appeared over the past few days. He denies pain, itching, or trauma. His medical his…
Mechanisms of disease · middle twist
A biopsy of the tracheal epithelium shows a single layer of cells with nuclei at different levels, cilia, and mucus-secreting goblet cells. Which of the followi…
Foundations · common
Which of the following is TRUE about stratified columnar epithelium?
Foundations · niche
Which function is performed by stratified cuboidal epithelium?
Foundations · common