From the Guidelines
For a standard-sized male, a tracheostomy tube size of 8.0-9.0 mm internal diameter (ID) is recommended. This size range is based on the most recent and highest quality study available, which suggests that a tracheal tube size of 8.0-9.0 mm ID is suitable for men, in line with local practice 1. When selecting a tracheostomy tube, it is essential to consider both the inner diameter, which affects airflow resistance, and the outer diameter, which impacts the fit within the trachea.
Some key considerations when choosing a tracheostomy tube include:
- Inner diameter: affects airflow resistance
- Outer diameter: impacts fit within the trachea
- Length: standard adult tubes typically measure 70-80 mm in length, but a longer tube may be necessary for patients with a thick neck or obesity
- Cuff pressure: should be maintained between 20-25 cmH2O to prevent tracheal injury while ensuring an adequate seal
It is crucial to have a smaller size (7.0 mm) available during initial placement in case the recommended size does not fit properly. After placement, it is essential to confirm proper positioning with a chest X-ray and assess for adequate ventilation. Individual patient anatomy varies, so clinical assessment remains vital when selecting the appropriate tracheostomy tube size 1.
From the Research
Tracheostomy Tube Size for Standard-Sized Male
- The size of the tracheal tube is often generically selected according to sex, with 7-7.5 mm and 8-8.5 mm tubes recommended in women and men, respectively 2.
- For a standard-sized male, an 8-8.5 mm tracheostomy tube is typically recommended 2.
- However, tracheal diameter in adults is highly variable and can be affected by height and sex, suggesting that a more individualized approach to selecting tracheostomy tube size may be necessary 2.
- Imaging of the airway preoperatively, such as CT scans and chest radiographs, can aid in determining the most appropriate size tube for a patient 3.
- Measurements of the airway, such as tracheal diameter at the endotracheal tube tip, carina, and midpoint of larynx to carina, can be used to predict the appropriate tracheostomy tube size 3.
Factors to Consider When Selecting Tracheostomy Tube Size
- The length of the tube may also be an important factor in selecting the appropriate tracheostomy tube size 4.
- A high riding cuff can be a common cause of malpositioning, resulting in an audible leak and a need to change the tracheostomy tube subsequently 4.
- The use of smaller tracheostomy tubes (e.g. ≤8.0 mm internal diameter) may increase the risk of malpositioning, particularly in patients with a greater skin to trachea depth 4.
- The internal diameter of the tube corresponds to its clinical utility, and tracheal tubes as small as 6.0 mm can accommodate routinely used intubation aids, suction devices, and slim-line fibreoptic bronchoscopes 2.
Additional Considerations
- Positive pressure ventilation can be performed without increasing the risk of ventilator-induced lung injury or air trapping, even when high minute volumes are required, using smaller tracheostomy tubes 2.
- There is no demonstrable increased risk of aspiration or cuff pressure damage when using smaller tracheostomy tubes 2.
- The adequate cuff volume for tracheostomy tubes can vary depending on the type of tube and internal diameter, and should be determined on an individual basis 5.