What IV needle size should I use?

A: 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 such as:

  • Prescribed therapy/type of solution
  • Duration of treatment
  • Peripheral vein availability/vein integrity
  • Diagnosis /Age
  • 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.”  A small gauge catheter results in less trauma to the vein, promotes proper hemodilution of the solution, and allows adequate blood flow around the catheter wall. All these factors promote increased catheter dwell time and improve patient outcomes.

The recommendation for catheter selection from the textbook “Infusion Nursing: An Evidence based Approach” include the following:

Catheter Size (Gauge) /Clinical Applications

24g – Fragile veins; for intermittent and continuous infusions

22g – Children/Older adults; intermittent general infusions

20g – Adults/continuous infusions

14g, 16g, 18g –  Trauma and surgery

It is important to note that for transfusions of blood or blood products, 14-24g can be used for adults and 22g-24g for pediatrics and neonates.

In an emergency situation where rapid infusion of large amounts of fluids are necessary, a larger gauge catheter may be used. Catheters inserted in emergency situations should be removed and replaced as soon as the patient is stabilized, but within 24 hours of the emergency as one cannot ensure that the site was adequately prepped or that aseptic technique was maintained.

So now you know….thanks for the question.