Laser debridement – a safer and less painful alternative to sharp debridement for treating chronic wounds
Ever since it was first conceptualised in the early 1960s, laser technology has occupied a vital niche in medical surgery. Lasers are used today by a large number of specialities such as dentistry, ophthalmology, vascular surgery, otolaryngology and dermatology. Lasers are useful in treating hypertrophic scars, removing skin lesions, laparoscopic surgery and vein ablation. Deeper integration of laser technology into podiatry may improve therapeutic outcomes of many conditions that are challenging to treat. Debridement is one of the cornerstones in wound management. Several studies suggest that a wound treated with serial debridement gets less infected and heals faster than a wound that has received minimal or no wound debridement. This can be attributed to wound debridement reducing bacterial burden, removing excess pressure, stimulating cytokine and facilitating drainage.
At present, sharp debridement is preferred by a vast majority of physicians because of its convenience and efficiency. However, it is hampered by the lack of a uniform technique along with it being quite painful for the patient. Laser debridement is a lesser known technique that has mostly been limited to burn treatment until now. Its key advantages over sharp debridement are precision and tissue ablation uniformity. This reduces wound trauma, improves patient comfort, and promotes quicker wound healing. Laser debridement relies on controlled vaporisation of superficial wound bed layers that contain necrotic particles and unwanted microbes. The tissue ablation depth depends on the laser type used along with the number of passes performed and it can range from 2 μm to 150 μm per pass. Unlike other methods that depend on manual controls, laser debridement is an electronic process, improving ablation precision and reducing incidental damage to healthy tissues substantially.
One major disadvantage of laser debridement is that it damages surrounding tissue by thermal diffusion. Heat transmitted beyond the targeted tissue can cause injury and is an unfortunate side-effect of thermal lasers. To reduce the thermal damage caused to healthy tissue, manufacturers have brought about several improvements to traditional lasers. One example is the pulsed beam system that produces laser energy in a rapid series of high-power pulses. Since thermal energy produced this way is greater than or equal to the energy produced by continuous beams, optimal vaporisation is achieved. It also minimises thermal injury, as the target tissue is exposed to higher temperatures for a shorter duration. Another innovation is the Erbium-doped yttrium-aluminium-garnet laser that reduces thermal damage to irradiated tissues. Er: YAG lasers have minimal tissue penetration as water absorbs energy 12 times more effectively than it absorbs CO2 lasers. In addition, charred debris gets from the wound surface without leaving behind a necrotic eschar like most other lasers as water expands very rapidly within the tissue. Residual necrotic tissue burden reduction and finer ablation properties are some of the key advantages of Er: YAG lasers, making them optimum for wound debridement.
While there is a fair amount of knowledge about the biological effects of laser debridement, current research focusses on molecular regenerative pathways within tissues furthest from the laser heat. Numerous cases have documented the advantages of laser wound debridement, but no thorough study comparing it to other types of wound bed preparation has been conducted till date. Laser debridement has been conducted on a few individuals suffering from diabetes mellitus, multiple bilateral chronic venous leg ulcers and peripheral neuropathy. In the case of diabetic patients, laser debridement was found to significantly reduce discomfort and allow a far more precise wound bed preparation that completely removed fibrotic tissue. Patients afflicted with multiple bilateral chronic venous leg ulcers have been found to be intensely uncomfortable during sharp debridement but are able to tolerate laser debridement for the entire duration of the treatment. Patients with neuropathy have also been treated quickly with fibrotic tissue removed and a healthy granulation tissue base exposed rapidly without damaging adjacent tissue.
Although these are preliminary results, they suggest that laser debridement allows a more successful wound bed preparation than sharp debridement and also substantially reduces the procedural pain experienced. More studies are needed to definitively prove the efficacy of this treatment, but if initial studies are anything to go by, laser debridement is well and truly the future of chronic wound management.