Inclusion Criteria:  18 years or older and able to give consent  Exclusion Criteria:  Unable to give consent Infection coloring or bruises at the puncture site (use of corticosteroid etc). No vein signs visible after application of vein stasis. Allergy to coolant spray. Contraindication for vein stasis or vein cannulation (ex Raynauds disease etc). Has participated earlier in the trial.