Track-Etched Membranes for Flap-Sparing Skin Grafting

BACKGROUND: Skin burns are among the most prevalent types of household and combat injuries. Burns are the sixth most prevalent type of injury in Russia, accounting for 2% of the total injury rate, which is more than 300,000 cases annually.

Superficial burns are the most common type of burn injury and generally resolve without the need for significant medical intervention. However, deep injuries require urgent skin repair. The scarcity of donor tissues is a challenge of treating extensive burns. In such cases, flap-sparing and extra-flap-sparing surgical techniques are recommended.

AIM: This work aimed to assess the efficacy of track-etched membranes in a wide range of pore sizes for wound coating in the surgical management of deep skin burns in an animal model.

METHODS: The study was conducted on 37 outbred rats. Two contact IIIB burn wounds were generated in the dorsal region of each animal. Eschars were then surgically excised down to the fascia. Skin autografts were transplanted at 24 hours after the burn injury. The postoperative wounds were then covered with a gauze cloth impregnated with Levomekol ointment or a track-etched membrane wound dressing with pore sizes ranging from 0.6 to 4 µm. The dressing was first changed on postoperative day 3 and then after 2 or 3 days. The observation period was 28 days. The transplanted graft survival, mean wound-healing rate, and time to complete wound healing were assessed. Changes in wound moisture levels and moisture loss through the wound dressing were measured.

RESULTS: For the treatment of deep burns, both versions of track-etched membranes were shown to be superior to conventional gauze bandage with water-soluble ointment with regard to the following criteria: transplanted graft survival (28% and 34% higher), mean wound-healing rate (0.49%/day and 0.94%/day more), and time to complete healing (2.3 and 3.9 days less). Furthermore, track-etched membranes reduced the moisture loss of the wound (29% and 24% less vs a gauze bandage), promoted the moisture retention of the wound (94% and 62% higher vs a gauze bandage), prevented wound drying, and created a favorable environment for wound healing. Track-etched membranes with large pores (4 µm) offered 9% higher moisture permeability than those with 0.6-µm pores did. Track-etched membranes with 4-µm pores used for burn wound closure after surgical debridement were demonstrated to facilitate wound drainage and reduce healing time compared with those with 0.6-µm pores (with healing times 1.7 days shorter and a mean healing rate of 0.44%/day higher).

CONCLUSION: Track-etched membranes with large pores (4 µm) provide the highest rate of graft survival after the surgical excision of the eschar and create a favorable environment for wound edge reepithelization. Track-etched membranes offer a reliable solution for wound protection against infection and for maintaining proper water balance.