Carbon Dioxide Laser Ablation With Immediate Autografting in a Full-Thickness Porcine Burn Model

Abstract

ObjectiveTo compare the long-term clinical and histologic outcome of immediate autografting of full-thickness burn wounds ablated with a high-power continuous-wave C02 laser to sharply d6-brided wounds in a porcine model. Summary Background DataContinuous-wave CO2 lasers have performed poorly as tools for burn excision because the large amount of thermal damage to viable subeschar tissues precluded successful autografting. However, a new technique, in which a high-power laser is rapidly scanned over the eschar, results in eschar vaporization without significant damage to underlying viable tissues, allowing successful immediate autografting. MethodsFull-thickness paravertebral burn wounds measuring 36 cm2 were created on 11 farm swine. Wounds were ablated to adipose tissue 48 hours later using either a surgical blade or a 1 50-Watt continuous-wave CO2 laser deflected by an x-y galvanometric scanner that translated the beam over the tissue surface, removing 200 ,um of tissue per scan. Both sites were immediately autografted and serially evaluated clinically and histologically for 180 days. ResultsThe laser-treated sftes were nearly bloodless. The mean residual thermal damage was 0.18 ± 0.05 mm. The mean graft take was 96 ± 1 1% in manual sftes and 93 ± 8% in laser sites. On postoperative day 7, the thickness of granulation tissue at the graftwound bed interface was greater in laser-d6brded sites. By postoperative day 180, the manual and laser sites were histologicalty identical. Vancouver scar assessment revealed no differences in scarning at postoperative day 180. ConclusionsLong-term scarring, based on Vancouver scar assessments and histologic evaluation, was equivalent at 6 months in laserablated and sharply excised sites. Should this technology become practical, the potential clinical implications include a reduction in surgical blood loss without sacrifice of immediate engraftment rates or long-term outcome.Although early excision and grafting of deep dermal and full-thickness burns has improved patient survival rates,'

Early versus Delayed Excision and Grafting of Full-Thickness Burns in a Porcine Model: A Randomized Study

“…Glatter et al created 6 × 6-cm full-thickness burns by exposing 11 Yorkshire pigs (25 kg) to a brass block heated to 100°C and held with mild pressure on the skin surface for 20 seconds. 19 Forty-eight hours after injury, some of the burns were excised surgically down to fat with a handheld dermatome or débrided with a carbon dioxide laser, also down to adipose tissue. The débrided wounds were then covered with a split-thickness (0.4 mm) autograft harvested with a gas-driven dermatome and expanded at a ratio of 1:1.5.…”

A haemostatic technique using silicone gel dressing for burn surgery

“…Even though multiple haemostatic techniques have been proposed to address this problem, there are as yet no definitive answers (7). The previously reported techniques include the application of topical epinephrine with or without thrombin to excised wounds and/or donor sites (9)(10)(11)(12); the subcutaneous infiltration of vasoconstrictors such as epinephrine (13)(14)(15)(16)(17)(18), phenylephrine (13) or vasopressin (2) at donor and/or excision sites; the administration of systemic vasopressin (19); excision with a laser (20)(21)(22) and the use of limb tourniquets (23,24). Under the blood conservation strategy using these techniques, the amount of blood loss was about 120 ml per percentage excised (3).…”

Improved staining method for determining the extent of thermal damage to cells

“…We and other authors [1][2][3][4][5][6][7][8] have used enzyme histochemistry to evaluate thermal damage immediately following irradiation. Thermal damage to cells results from the denaturation of biomolecules.…”

“…In order to limit the number of animals used in experiments and to increase the speed at which experiments can be completed, there is a need for methods that do not require the survival of the animals after the treatment. For laser-induced thermal damage, we and others [1][2][3][4][5][6][7][8] have used enzyme histochemical stains of tissue as an immediate method to assay for cell viability in tissue. This method shows decreased to absent staining when there has been thermal denaturation of many globular proteins.…”