Table 3

A list of documented methods used to disinfect nebulisers

MethodEvidence
Chemical methods
 Acetic acid/vinegar
  • Ineffective against CF pathogens such as B. cenocepacia, S. aureus and MRSA [52]

 Benzyl ammonium chloride (Control III; Maril Inc., Tustin, CA, USA)
  • Not recommended due to narrow spectrum of activity and slow action [26]

 Ethyl alcohol/ethanol (70%)
  • Has been reported to reduce fungal and bacterial contamination of nebulisers but not completely [53]

 Isopropyl alcohol/propanol (70%)
  • Will lose activity over time; therefore, needs to be regularly replaced

    Saliva and sputa may protect microorganisms from the action of alcohol; therefore, prior washing of devices is required

    May be ineffective against mycobacteria [54]

    It has been reported that isopropyl alcohol disinfection does not affect nebuliser output[55]

 Hydrogen peroxide (3%)
  • Although listed in the CFF-IP&C guidelines (3% hydrogen peroxide for 30 min), there is limited evidence supporting disinfection of nebulisers with hydrogen peroxide [26]

 Sodium hypochlorite
  • Although hypochlorite disinfection has been shown to decrease the contamination of nebulisers due to commensal and environmental organisms, a similar reduction has not been observed in the case of CF pathogens [10, 56]

    Corrosive chemicals such as hypochlorite are prohibited for disinfecting the mesh membrane of the e-Flow rapid nebuliser [5]

 Ozone
  • Commercially available SoClean (Peterborough, NH, USA) ozone machine has been examined with type strains of B. cepacia, P. aeruginosa, S. aureus and S. maltophilia

    Preliminary findings have shown a 5-min infusion followed by a 120-min dwell time to be effective against these organisms when spiked onto a Pari LCPlus nebuliser, without affecting nebuliser output

    Further investigation is required in relation to nontuberculous mycobacteria and clinical strains of CF pathogens [57]

 Squalamine
  • Squalamine (a steroid–polyamine conjugate compound with broad spectrum antimicrobial activity) targets membrane integrity, and has potential to reduce levels of S. aureus, P. aeruginosa, Candida albicans and Aspergillus niger on contaminated nebulisers [58]

    Further work needs to be completed prior to advocating the employment of this molecule

Heat methods
 Boiling (continuous boil in water for 5 mins)
  • The CFF-IP&C guidelines and manufacturers’ guidelines recommend that nebulisers should be disinfected by placing them in boiling water for 5 mins [26]

    Decrease in nebuliser output with Pari LC Plus® device following repeated disinfection by boiling [55]; however, experimental limitations must be considered [59]

 Steam (electric baby bottle steam disinfectors)
  • See table 4

 Steam (microwave) (place in microwave-safe receptacle submerged in water and microwave for 5 mins, 2.45 GHz)
  • Evidence in CFF-IP&C guideline taken from [65–67]; none of these studies employed nebulisers

    This method cannot be used with nebulisers that contain metal components (e.g. mesh in the eFlow rapid)

    Dutch study demonstrated that nebulisers contaminated with Enterococcus faecalis, S. aureus and P. aeruginosa were free of microorganisms after microwave treatment (650 W, 9 min) [68]

 Dishwasher disinfection (≥70°C/158°F for 30 min)
  • Although listed in the CFF-IP&C guidelines [26], there is limited evidence supporting disinfection of nebulisers using high-temperature dishwashers

 Autoclave (a maximum of 277°F or 136°C)
  • Certain nebuliser parts may be sterilised using autoclave methods (e.g. Pari Reusable Nebuliser parts, except mask and tubing) [69]

MRSA: methicillin-resistant S. aureus.