Wide-bore catheters are those with an internal diameter of 4 mm or greater.

The variety of devices available use either the needle-over-cannula technique, e.g. Rusch Quicktrach (Fig 1) or the Seldinger technique, e.g. Cook Melker (Fig 2).

The catheters may be either cuffed or uncuffed. It is likely that more effective ventilation can be achieved via cuffed catheters.

The larger internal diameter of these devices means there is less resistance to flow. They can therefore be used with conventional means of ventilation.

While there is a lower failure rate than seen with narrow-bore cannulae, wide-bore cricothyrotomy cannulae can still be incorrectly placed, become dislodged or the cannulae may kink.

The Difficult Airway Society do not recommend these devices for emergency FONA. Their use in the CICO situation should be limited to experienced clinicians who use them in routine clinical practice.