IO for OHCA – Humeral Head or Tibia?

April 17, 2024

Written by Megan Hilbert

Spoon Feed
In subgroup analysis, there may be more successful ROSC in patients with upper extremity IO access compared to lower extremity access in OHCA, but these results should be adopted with caution.

IO(U) access – would you like it in the arm or the leg?
There are many factors that go into the success of obtaining ROSC in OHCA including, but not limited to: initial rhythm, bystander CPR, airway management strategies – the list is endless. This retrospective study tried to determine whether location of IO access (upper versus lower extremity) could increase rates of ROSC as well as survival to discharge. With subgroup analyses in a multivariable logistic regression model, there was greater odds of ROSC (aOR 1.11, 95%CI 1.08-1.15) and survival to discharge to home (aOR 1.23, 1.02-1.48) with upper extremity IO access.

So everyone should go for the humerus right? Not quite. Importantly, this study evaluated the anatomical site of first successful IO access attempt. Success rates for IO placement are higher in the tibia compared to the proximal humerus. Not only that, there is in an increase in dislodgement at the humeral site. These are considerable limitations to consider (and the authors mention that). I would rather have a more successful access location that is less likely to fail and may be less limited by patient body habitus. Having said that, this study does demonstrate some areas for potential improvement in the field of OHCA. Given that it may improve outcomes compared to tibial access, EMS agencies may want to consider providing additional training in humeral IO access.

How will this change my practice?
I do not regularly engage in pre-hospital care, so this will not significantly impact my practice, but it may be something to consider for providers who practice in that arena or are who are EMS medical directors.

Editor’s note: With propensity score matching, there was statistically significant improvement in ROSC but not survival to discharge or survival to discharge home with humeral IO vs tibial. However, this is worth further study. ~Clay Smith

Source
Retrospective Comparison of Upper and Lower Extremity Intraosseous Access During Out-of-Hospital Cardiac Arrest Resuscitation. Prehosp Emerg Care. 2024 Mar 26:1-8. doi: 10.1080/10903127.2024.2321285. Epub ahead of print. PMID: 38416867.