Possible hazards from irradiation with the carbon dioxide laser

Area of Science:

• Biomedical Engineering
• Laser Surgery
• Microbiology

Background:

• The carbon dioxide (CO2) laser is widely used in surgery.
• It is generally assumed to create a sterile surgical field by vaporizing tissue and microorganisms.
• Previous studies at high irradiance levels did not detect viable particles in the laser plume.

Purpose of the Study:

• To investigate the potential for viable particle dissemination during CO2 laser vaporization.
• To specifically examine lower irradiance levels currently used in clinical practice.
• To reassess the assumption of a sterile field during CO2 laser procedures.

Main Methods:

• Fresh post-mortem skin samples were inoculated with bacterial spores.
• Samples were vaporized using a CO2 laser at varying irradiance levels (below 500 W/cm2 and above 997 W/cm2).
• Laser plume and splatter were collected and cultured to detect viable spores.

Main Results:

• Viable bacterial spores were detected in the plume and splatter of 5 out of 13 specimens treated at low irradiance (< 500 W/cm2).
• No viable spores were found in 20 specimens treated at high irradiance (> 997 W/cm2).
• These findings indicate that low-irradiance CO2 laser vaporization may disseminate viable particles.

Conclusions:

• The assumption that CO2 laser vaporization always produces a sterile field may be incorrect.
• Low-irradiance CO2 laser use can potentially disseminate viable microorganisms.
• This has implications for treating potentially infectious lesions and highlights the need for appropriate safety precautions.