weekly_question 15/9/2024

[Admin]

An 8-year-old has suffered a 30% TBSA burn. It is estimated that the burns are deep partial thickness or full thickness and burn wound debridement is planned. The surgeon discusses coverage options with the family, and in view of extreme parental and child anxiety, the option of donor skin harvest for immediate autologous coverage is excluded.

The best option for immediate coverage of the debrided, clean burn wound in this child is:

A human skin allograft

B silver sulfadiazine

C cryopreserved human amnion

D occlusive hydrogel dressing

[Admin]

Correct answer
A human skin allograft

Burn wounds in children account for about 25% of total burns presenting for emergency care and are a significant source of preventable morbidity and mortality. Referral criteria to pediatric burn centers include partial or full thickness burns >10% total body surface area (TBSA) as well as burns to face, hands, feet, and genitalia. Choice of treatment depends on the size, depth and location of the burn and availability of skin substitutes.

Autologous skin transplantation is still considered the gold standard for burn wound coverage either as a split-thickness (STSG) or full-thickness skin graft (FTSG). STSGs involve the transfer of epidermis and a partial thickness of underlying dermis from a donor site, often the lateral thigh, to a clean, well-vascularized wound bed for graft ingrowth and integration. Because donor sites retain underlying dermis, skin will regrow in 2-3 weeks and can be re-harvested for subsequent applications. The limitations to STSG coverage are skin fragility and an irregular texture, abnormal pigmentation, lack of hair, poor sensation and an increased risk of secondary contracture. While FTSGs essentially provide complete replacement, the donor site must be closed primarily, limiting graft size. Given their increased thickness, FTSGs require a robust wound bed for complete graft take and are more likely to undergo primary contracture.

Human cadaver skin (allograft) provides temporary wound coverage and encourages wound bed vascularization but will be rejected within a few weeks; therefore a long-term autologous coverage solution will be required. Human skin allografts are widely used for temporary burn wound coverage in preparation for either autologous STSG or a bioengineered autologous alternative derived from harvested skin. Use of porcine xenografts as temporary burn wound coverage previously offered a promising, cost-effective alternative to human skin, but is currently not available. These differ from acellular matrices. Current research is evaluating the effectiveness of genetic manipulation as a strategy to reduce donor xenograft immunogenicity.

Human amniotic membrane has also been shown to have potential as a biological dressing but is limited by its availability and requirement for fresh storage at -90C or lyophilization. Its use has primarily been reported for refractory chronic wounds (diabetic ulcers) as an alternative to standard wound care.

Despite their cost, commercially available acellular dermal matrices from a variety of species (e.g. human-Alloderm™, bovine-Integra™) are gaining in popularity as coverage options for burn wound and soft tissue defect reconstruction. They are decellularized to leave behind a scaffold for recipient cell infiltration, retain cytokines and growth factors to facilitate healing but are immunologically inert. They provide a barrier against infection, decrease fluid losses and create a favorable wound bed for future autologous grafting with a “thin” STSG, which is beneficial for donor sites, given the reduced requirement for dermal elements.

An occlusive dressing would offer little in the way of reduced fluid loss or infection prevention.

[Manal Dhaiban]

C

[Mohammad Alnajashi]

B

[Abd El wahed]

C

[AbdullahZahi95]

A

[Ayman]

B

[Khulood]

B

[Dr.Shumaila]

C

[Admin]

Correct answer
A human skin allograft

Burn wounds in children account for about 25% of total burns presenting for emergency care and are a significant source of preventable morbidity and mortality. Referral criteria to pediatric burn centers include partial or full thickness burns >10% total body surface area (TBSA) as well as burns to face, hands, feet, and genitalia. Choice of treatment depends on the size, depth and location of the burn and availability of skin substitutes.

Autologous skin transplantation is still considered the gold standard for burn wound coverage either as a split-thickness (STSG) or full-thickness skin graft (FTSG). STSGs involve the transfer of epidermis and a partial thickness of underlying dermis from a donor site, often the lateral thigh, to a clean, well-vascularized wound bed for graft ingrowth and integration. Because donor sites retain underlying dermis, skin will regrow in 2-3 weeks and can be re-harvested for subsequent applications. The limitations to STSG coverage are skin fragility and an irregular texture, abnormal pigmentation, lack of hair, poor sensation and an increased risk of secondary contracture. While FTSGs essentially provide complete replacement, the donor site must be closed primarily, limiting graft size. Given their increased thickness, FTSGs require a robust wound bed for complete graft take and are more likely to undergo primary contracture.

Human cadaver skin (allograft) provides temporary wound coverage and encourages wound bed vascularization but will be rejected within a few weeks; therefore a long-term autologous coverage solution will be required. Human skin allografts are widely used for temporary burn wound coverage in preparation for either autologous STSG or a bioengineered autologous alternative derived from harvested skin. Use of porcine xenografts as temporary burn wound coverage previously offered a promising, cost-effective alternative to human skin, but is currently not available. These differ from acellular matrices. Current research is evaluating the effectiveness of genetic manipulation as a strategy to reduce donor xenograft immunogenicity.

Human amniotic membrane has also been shown to have potential as a biological dressing but is limited by its availability and requirement for fresh storage at -90C or lyophilization. Its use has primarily been reported for refractory chronic wounds (diabetic ulcers) as an alternative to standard wound care.

Despite their cost, commercially available acellular dermal matrices from a variety of species (e.g. human-Alloderm™, bovine-Integra™) are gaining in popularity as coverage options for burn wound and soft tissue defect reconstruction. They are decellularized to leave behind a scaffold for recipient cell infiltration, retain cytokines and growth factors to facilitate healing but are immunologically inert. They provide a barrier against infection, decrease fluid losses and create a favorable wound bed for future autologous grafting with a “thin” STSG, which is beneficial for donor sites, given the reduced requirement for dermal elements.

An occlusive dressing would offer little in the way of reduced fluid loss or infection prevention.