Does Defibrillator Pad Placement Matter for OHCA?

October 14, 2024

Written by Millie Cossé

Spoon Feed
Anterior-posterior (AP) – compared to standard anterolateral (AL) defibrillator pad placement – was associated with higher rates of ROSC among patients with out-of-hospital-cardiac-arrest (OHCA), but no difference in survival to discharge or functional survival at discharge was observed.

Straight to the heart
This prospective observational study assessed associated with initial pad placement AP or anterior-lateral (AL)) with outcomes among patients with out-of-hospital cardiac arrest.

The primary outcome was ROSC at any time, and secondary outcomes included pulses at ED arrival, survival to admission, survival to discharge, and functional survival at hospital discharge. AP placement had a higher adjusted odds ratio of ROSC at any time (2.64; 95%CI 0.78-2.30), but there was no statistically significant difference noted among the secondary outcomes.

This study had some real limitations. Only one EMS system was included, and paramedics were able to choose how the pads were placed (of note, obese patients were more likely to have AL placement).

How will this change my practice?
I tend to start with AP pad placement whenever possible. Given the current body of evidence, I read this paper as a weak signal that AP placement may be superior. AL placement is easier while compressions are going, so it is important to pre-brief your team and have someone on either side of the patient to quickly lift them up and expose their back for pad placement in the early phase of the resuscitation. Everyone is trying to limit interruptions to compressions, and doing this well takes some practice and coordination.

Editor’s note: Given that DOSE VF found AP pad placement – called “vector change” in that study – had a NNT 12 for survival to hospital discharge (21.7% AP placement vs. 13.3% standard AL placement), this study provides lower quality evidence that confirms the same. ~Clay Smith

Source
Initial Defibrillator Pad Position and Outcomes for Shockable Out-of-Hospital Cardiac Arrest. JAMA Netw Open. 2024 Sep 3;7(9):e2431673. doi: 10.1001/jamanetworkopen.2024.31673. PMID: 39250154; PMCID: PMC11385052.