ZOLL AED Plus Post-Use Inspection and Testing Case Study

Following a clinical deployment, a clinic requested a post-use functional evaluation of their ZOLL AED Plus defibrillator. Because automated external defibrillators are critical emergency resuscitation devices, clinical readiness requires prompt post-event inspection and replenishment of disposable accessories. Upon arrival, the technician noted the unit lacked attached electrode pads following its recent use.

Technician investigation

The technician initiated the post-use inspection by assessing the external housing and checking for required accessories. It was verified that no pads were currently connected to the device. To prepare the AED for functional evaluation, replacement electrode pads were attached and their expiration date of March 9, 2029 was documented. The technician then prepared test equipment to measure output energy and evaluate internal diagnostics.

Root cause

A root cause was not applicable or documented because the service call was an scheduled post-use functional verification rather than an equipment breakdown.

• Internal circuit failure
• Discharge energy inaccuracy

Resolution

The technician installed replacement pads onto the ZOLL AED Plus and recorded the expiration date. A discharge simulation was performed, yielding a measured output of 123.5 joules. The unit internal self-test was initiated and completed with an OK status. All operational functions were confirmed to be in good working order.

Verification

• Discharge energy simulation
• Internal self-test execution
• Visual inspection of pad expiration date

Energy discharge simulation confirms that the defibrillator can deliver the appropriate therapeutic dose within specified limits during a cardiac event. Running the internal diagnostic self-test verifies processor integrity, audio-visual prompts, and capacitor circuitry prior to redeployment.

Technician insight

Post-use evaluations must always pair consumable replenishment with active output testing. Even if an AED self-reports normal readiness status, measuring actual delivered energy via simulation ensures high-voltage circuitry suffered no degradation during clinical discharge.

What can cause this issue?

• Depletion or removal of single-use electrode pads during patient resuscitation
• Expired shelf life on gel electrode assemblies
• Internal self-test failures due to low battery voltage
• Capacitor charge or discharge delivery circuit faults

This service call was a routine post-use evaluation where missing pads were replenished and the unit verified through simulation and diagnostic testing.

FAQ

What must be done to an AED immediately after it is used?

After deployment, an AED requires cleaning, replacement of single-use electrode pads, battery evaluation, inspection of physical components, and post-use functional testing to ensure it is fully ready for the next emergency.

What energy level does a ZOLL AED Plus deliver during testing?

The ZOLL AED Plus delivers a biphasic shock waveform. During this verified service visit, energy delivery was simulated and recorded at 123.5 joules, confirming normal discharge output.

How long do ZOLL AED Plus pads remain valid?

Pads typically have multi-year expiration dates. On this service call, the replacement pads installed had an expiration date recorded for March 2029.

Why is an energy simulation test necessary if the AED self-test passes?

An internal self-test checks circuit continuity and system readiness, but an external discharge simulation physically measures delivered joules into a calibrated test load to confirm shock accuracy.