Tracheostomy tube type and inner cannula selection impact pressure and resistance to airflow.

Lee Pryor, Claire Baldwin, Elizabeth Ward, Petrea Cornwell, Stephanie O'Connor, Marianne Chapman, Andrew Bersten

    Research output: Contribution to journalArticlepeer-review

    8 Citations (Scopus)


    BACKGROUND: Advancements in tracheostomy tube design now provide clinicians with a range of options to facilitate communication for individuals receiving ventilator assistance through a cuffed tube. Little is known about the impact of these modern design features on resistance to air flow. METHODS: We undertook a bench model test to measure pressure-flow characteristics and resistance of a range of tubes of similar outer diameter, including those enabling subglottic suction and speech. A constant inspiratory ± expiratory air flow was generated at increasing flows up to 150 L/min through each tube (with or without optional, mandatory, or interchangeable inner cannula). Driving pressures were measured, and resistance was calculated (cm H2O/L/s). RESULTS: Pressures changed with increasing flow (P <.001) and tube type (P <.001), with differing patterns of pressure change according to the type of tube (P <.001) and direction of air flow. The singlelumen reference tube encountered the lowest inspiratory and expiratory pressures compared with all double-lumen tubes (P <.001); placement of an optional inner cannula increased bidirectional tube resistance by a factor of 3. For a tube with interchangeable inner cannulas, the type of cannula altered pressure and resistance differently (P <.001); the speech cannula in particular amplified pressure-flow changes and increased tube resistance by more than a factor of 4. CONCLUSIONS: Tracheostomy tube type and inner cannula selection imposed differing pressures and resistance to air flow during inspiration and expiration. These differences may be important when selecting airway equipment or when setting parameters for monitoring, particularly for patients receiving supported ventilation or during the weaning process.

    Original languageEnglish
    Pages (from-to)607-614
    Number of pages8
    JournalRespiratory Care
    Issue number5
    Publication statusPublished - 1 May 2016


    • Airway resistance
    • Phonation
    • Speech
    • Tracheostomy
    • Ventilator weaning
    • Work of breathing


    Dive into the research topics of 'Tracheostomy tube type and inner cannula selection impact pressure and resistance to airflow.'. Together they form a unique fingerprint.

    Cite this