Routine cleaning and autoclaving does not remove protein deposits from reusable laryngeal mask devices

Abstract

We tested the hypothesis that routine cleaning and autoclaving does not remove protein deposits from reusable laryngeal mask airways (LMAs). All previously used classic and flexible LMAs from a single hospital were tested. Each LMA was hand-washed in an enzymatic solution for 3 min, machine-washed with a disinfectant for 14 min at up to 85°C; dried for 30 min at 75°C, packaged in porous film, and autoclaved for 4 min at 134°C. Protein deposits were detected by immersion in a 1.2% erythrosin B solution, which stains for proteins present on surfaces. The outer surface, inner surface, and edges of the cuff, and the outer and inner surface of the airway tube were examined for the uptake of stain. The severity of staining was scored according to the percentage of surface area stained: nil, mild (>0%–20%), moderate (>20%–80%), and severe (>80%–100%). Fifty-nine LMAs were collected (16 classic and 43 flexible). Staining was detected on 15 (94%) classic LMAs and 39 (91%) flexible LMAs. All staining was graded as mild. Staining was less common on the inner surface than the outer surface or edges for both devices (all P < 0.004). Staining was less common with the airway tube than any location on the cuff (all P < 0.02). Two unused LMAs used as controls were without staining. We conclude that routine cleaning and autoclaving does not remove protein material from reusable LMAs.

IMPLICATIONS: Routine cleaning and autoclaving does not remove protein material from reusable laryngeal mask airway devices.