First, freeze the ice packs solid.  For children who are younger than 1 year or who don't like the cold, it can be eliminated.  Put the FROZEN ice pack under the elastic strap on Buzzy's back.

Blue Gel Wings insert exactly the same way.

Place Buzzy proximal to the site with a velcro strap or tourniquet.  Turn it on with ice pack in place, and leave it in place and vibrating during the IV.  The cold has NOT been found to vasoconstrict during our randomized controlled trials, but if a person is sensitive to cold they can hold the ice pack in their hand.  The gate control will be less effective, but the descending inhibitory control should work with the ice anywhere.