Seldinger techniques are an extension of the needle cricothyroidotomy procedure:

1. The needle enters the trachea through the cricothyroid membrane (Fig 1)
2. A wire is passed through the needle (Fig 2)
3. The needle is then removed and a wider-bore cannula mounted onto a dilator is then inserted over the wire (Fig 3)
4. Finally the wire is removed

The Cook Melker cricothyroidotomy kit (Fig 4) is an example of a combined surgical/percutaneous kit containing a wide-bore cannula with an internal diameter range of 4-6 mm. It can be inserted using either a standard Seldinger or surgical technique. The technique of insertion is familiar to anaesthetists, but may take longer to insert than the alternative devices. Both cuffed and uncuffed versions are available and the cannula is pre-loaded over a dilator prior to insertion.