Study: AED audiovisual feedback can improve outcomes, but has limitations
Using the audiovisual feedback mechanism within an automated external defibrillator (AED) can improve CPR-quality parameters including compression rates, correct hand position and leaning, according to a study published online April 1 in Resuscitation.

Henrik Fischer, MD, of the Medical University, Waehringer Gürtel in Vienna, Austria, and colleagues looked to better understand how use of audiovisual feedback technology within the AED can improve outcomes during basic life support performed by trained laypersons.

During the study, 68 teams with two flight attendants each performed 12 minutes of standard CPR with the AED’s audiovisual feedback mechanism enabled or disabled on manikins. Fischer et al reported CPR quality parameters during resuscitation in the prospective, randomized controlled trial.

Differences in compression rate and depth were measured as the study’s primary outcome. Additionally, the researchers looked at correct hand position and incomplete decompressions as the study’s secondary outcome.

The researchers reported that the group that utilized AEDs with the feedback mechanism delivered compression rates closest to the recommended guidelines compared with the control group, at 101 vs. 109 per minute. The feedback group also had more effective compressions and more compressions administered with correct hand position, 20 vs. 5 percent and 96 vs. 88 percent, respectively.

And while the feedback group also had less leaning, 21 vs. 77 percent, only the control group adhered to the recommended compression depths, 44 vs. 39 mm, what the researchers noted as a limitation.

“Use of an AED's audiovisual feedback system improved some CPR-quality parameters, thus confirming findings of earlier studies with the notable exception of decreased compression depth, which is a key parameter that might be linked to reduced cardiac output,” the authors concluded.