Effects of AED device features on performance by untrained laypersons.

• Abstract: OBJECTIVE: Our study evaluates the impact of features of automated external defibrillators (AEDs) on the performance and speed of untrained laypersons to deliver a shock and initiate CPR after a shock. METHODS: This was a randomized trial of volunteer laypersons without AED or advanced medical training. Subjects were assigned to use one of six different models of AEDs on a manikin in simulated cardiac arrest. No instructions on AED operation were provided. Primary endpoints were shock delivery and elapsed time from start to shock. Secondary endpoints included time to power-on, initiation of CPR, adequacy of pad placement and subjects' ratings of ease of use (1=very easy, 5=very difficult). RESULTS: Most subjects (109/120; 91%) were able to deliver a shock. Median time from start of scenario to shock delivery was 79 s (IQR: 67-99). Of the 11 participants who did not deliver shock, eight never powered on the device. Time to power-on was shorter in devices with open lid (median 12s, IQR 8-27 s) and pull handle (17s, IQR 9-20s) mechanisms than with a push button (37s, IQR 18-69 s; p=0.000). Pad position on the manikin was judged adequate for 86 (77%) of the 111 subjects who placed pads. Devices which gave more detailed voice instruction for pad placement had higher rates of adequate pad position [38/39 (97%) versus 50/73 (68%), p=0.001]. With AEDs that provided step-by-step CPR instruction, 49/58 (84%) subjects began CPR compared to 26/51 (51%) with AEDs that only prompted to start CPR (p=0.01). Participants rated all the models easy to use (overall mean 1.48; individual device means 1.28-1.71). CONCLUSIONS: Most untrained laypersons were successful in delivering a shock. Device features had the most impact on these functions: ability and time to power-on device, adequacy of pad position and initiation of CPR.
• Authors: Vincent N Mosesso Jr, Alan H Shapiro, Karen Stein, Kelly Burkett, Henry Wang (Affiliation: Department of Emergency Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA. mosessovn at upmc.edu)
• Journal: Resuscitation (Resuscitation) Vol. 80 Issue 11 Pg. 1285-9 (Nov 2009) ISSN: 1873-1570 [Electronic] Ireland
• PMID: 19720444 (Publication Type: Comparative Study, Journal Article, Randomized Controlled Trial)

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Cardiopulmonary Resuscitation (education, instrumentation)
• Clinical Competence
• Defibrillators (standards)
• Educational Measurement (statistics & numerical data)
• Electric Countershock (instrumentation)
• Female
• Follow-Up Studies
• Heart Arrest (therapy)
• Humans
• Male
• Manikins
• Middle Aged
• Posture
• Prospective Studies
• Time Factors
• Young Adult