One of the of the important considerations when starting an IV is the needle size. IV needles are sized by gauges, and the smaller the gauge number, the bigger the needle.
“The goal when selecting the proper gauge of an peripheral IV catheter is to ensure that the best device meets the patient’s needs. This means taking into consideration many factors including prescribed therapy/type of solution, duration of treatment, peripheral vein availability, vein integrity, diagnosis, age, and known complications of the device.”
The Infusion Nurses Society standards of practice states “the smallest gauge and length with the fewest number of lumens and shall be the least invasive device needed to accommodate and manage the prescribed therapy.”
Source: Infusion Nurse Blog