Evaluation of cleaning and sterilization of liposuction cannulas after intentional contamination with human fat, Mycobacterium abscessus subspecies bolletii and Geobacillus stearothermophilus.

BACKGROUND: The complex design of cannulas is a major challenge for reprocessing due to the retention and accumulation of fat residues.

AIM: To evaluate the cleaning of liposuction cannulas and the protective effects of the remaining fat residues on Mycobacterium abscessus subspecies bolletii (MASB) and Geobacillus stearothermophilus inactivation during steam sterilization.

METHODS: In Phase 1, six standard operating procedures (SOP) were evaluated for cleaning of liposuction cannulas. In Phase 2, the sectioned lumens of the liposuction cannulas were contaminated with the largest and smallest volume of human fat found in Phase 1, with the addition of MASB. In Phase 3, the same volumes of human fat from Phase 2 were used to contaminate paper strips containing G. stearothermophilus.

FINDINGS: In phase 1 the residual amount of fat ranged from 6 to 52mg. In phases 2 and 3, the minimum and maximum amounts of fat (6 to 50mg) protected microorganisms during steam sterilization at 134ºC for 1.5 and 3min.

CONCLUSION: Effective cleaning and sterilization of liposuction cannulas intentionally contaminated with human fat, MASB and G. stearothermophilus could not be performed.