Placement Matters
Best Practice Intraosseous Infusion

Although intravenous (IV) fluids have been around since the 1800’s, obtaining IV access is not always possible. Attempts at IV access may be unsuccessful for a variety of reasons, including: decompensated shock, vascular collapse, and/or poor lighting in the field. It is in these circumstances that intraosseous (IO) access makes for a great solution. It is well documented that blood, plasma, saline, and medication can all be given IO; this is no longer a debate.  IO access is a safe, effective, alternative to IV access.  What now needs to be considered is the placement location of an IO.

Proximal humerus placement verses proximal tibia placement seems to be the question that arises most frequently.  Experts believe proximal humerus is the better option for several reasons. For example, patients report less pain on insertion in the humerus than in the tibia ("10 myths," 2014). Additionally, the humerus can accommodate an infusion rate of up to 5 liters per hour while the tibia will only handle a rate of around 1 liter per hour. For the patient needing rapid fluid or blood replacement, the advantages of a humerus site are clear.

Humeral access not only allows a higher volume of fluid to be infused, it also delivers medications and fluids into the central circulation more rapidly.  The time it takes for meds or fluids infused through a humeral IO to reach central circulation is functionally the same as with internal jugular or subclavian access. Compare the following 2 videos found on YouTube. The first video shows an injection via tibial IO access,and the second shows an injection via humeral IO access.As you can see, the humeral injection allowed the iodine to enter central circulation in about 3 seconds, demonstrating that the humeral IO placement is preferable to tibial placement.  It is clear that humeral access allows critical patients to receive the most rapid delivery of medications and fluids.

In closing, here are a few more tidbits about intraosseous access just in case you still aren’t sold on the whole idea. Many people think that placement of an IO hurts. However, in study pain levels on insertion have been reported as 2 to 3 on a 1-10 scale. In addition, because an IO can usually be successfully placed with only one attempt, the pain it actually might be less than that of multiple attempts at IV access. As for infections such as osteomyelitis, in 1985 the published rate was 0.6%. Vidacare reports less than 1 in 100,000 with the EZ-IO system.  There is also a misconception that placement of an IO is a difficult skill; however, paramedics in training have a 90% first attempt success rate (Wampler, Shumaker, Bolleter, Manifold, &; Manifold, 2012).  In conclusion, the humerus provides a safe and effective alternative when IVs are not available or practical and is the preferred site for IO placement.