A typical set comprises:
A one- or two-part 22G needle for the initial puncture
A short 0.018-inch guidewire with flexible tip and supportive shaft
An interlocked dilator system. This varies from kit to kit. Those for hepatic and renal work often come with a metal stiffening cannula in addition to a coaxial inner dilator with a tapering tip inserted through a larger outer dilator, which will accept a 0.035/0.038-inch guidewire.
Remember to remove the inner dilator to allow insertion of the 0.035-inch wire.
Know what to ask for
Vascular access sets
This set is usually used for vascular access and has an inner 3F dilator and an outer 4F dilator. This permits introduction of the 0.035-inch wire.
Pedal access kit
This is very similar but has been specifically designed to help access the smallest of vessels. The needle is only 4 cm long and this makes back bleeding more obvious when the lumen has been accessed. The pedal access kit comes with a 0.021-inch wire, the coaxial dilator has an outer diameter of 4F and also a removable haemostatic valve, which allows this to be converted to a 2.9–3F ‘mini-sheath’.
Non-vascular access sets
Coaxial access set (neff/accustick)
This is the one to ask for if you are performing non-vascular intervention. Not only do you get a longer puncture needle but the sheath system has an inner metal stiffener to help prevent kinking of the guidewire and support the catheters as they pass through tissues/organs into deeper structures. In most of the kits, the final sheathed dilator will be at least 6F and often have a radio-opaque end-marker.