4. A Color Analogue pain score (CAS) (see outcome measures section for CAS background and description, and fig 2) will be obtained from the patient at the baseline, prior to the start of the procedure. The Jet application will occur at the insertion site, prior to the needle being inserted into the skin. A CAS pain score will be obtained from the patient subsequent to administration of the device. The provider will wait thirty seconds prior to insertion of the needle into the skin. A CAS pain score for needle insertion will be collected after completion of the procedure. After one minute a post procedure CAS score will be collected. The parent and/or support staff will be with the child throughout the entire procedure.