Safe Use of Refurbished Defibrillators and AEDs

Defibrillators and Automated External Defibrillators (AEDs) are life-critical devices — the difference between a functioning and a failed unit is measured in survival rates during cardiac arrest. Because these devices sit unused for long stretches between emergencies, structured maintenance, battery/pad management, and periodic testing are essential, especially for refurbished units entering service in new facilities. This article summarizes practical safe-use, maintenance, and testing guidance drawn from FDA and industry sources.

Understanding the Device Categories

• Manual/advanced defibrillators — used by trained clinicians in hospitals; allow manual energy selection, synchronized cardioversion, and often external pacing and multi-parameter monitoring.
• AEDs (Automated External Defibrillators) — designed for use by minimally trained responders; automatically analyze rhythm and prompt the user through voice/visual instructions (FDA, Automated External Defibrillators (AEDs)).

Both categories are FDA-regulated devices, and the FDA maintains specific guidance on accessory compatibility: manufacturers of AED accessories such as batteries, pad electrodes, and adapters were required to obtain premarket approval (PMA) for continued marketing, and non-FDA-approved AEDs may lose access to compatible accessories over time (FDA AED page). Buyers of secondary-market defibrillators should confirm the unit's regulatory status and the ongoing availability of pads and batteries in the destination market before purchase.

Daily, Weekly, and Monthly Readiness Checks

Defibrillators — particularly AEDs kept on standby — require a tiered inspection schedule rather than a single annual check.

A written, facility-specific policy defining inspection frequency and rationale is recommended, and inspection/test results should be logged and retained for audit (FDA AED Inspection and Maintenance Discussion, Regulations.gov docket).

Battery Management

• AED and defibrillator batteries are typically lithium-based and degrade gradually even when not used; expiration dates reflect the point at which stored charge can no longer be guaranteed.
• Typical in-hospital defibrillator battery replacement cycles are around two years, though this varies by manufacturer and model — always follow the specific unit's service manual (Regulations.gov, FDA AED docket testimony).
• Verify that batteries are actively charging when the unit is on standby power, and confirm charge status as part of routine checks.
• Do not perform battery insertion/operational tests too frequently — this can shorten battery life. Reserve full battery-operation tests for when the unit is placed into service, when the battery is replaced, when pads are replaced, or after physical damage or actual clinical use (FDA AED Maintenance discussion).
• Replace batteries immediately after any actual emergency use, regardless of remaining indicated charge.
• Store spare batteries away from direct sunlight and temperature extremes to preserve shelf life.

Electrode Pad Management

• Electrode pad gel dries out over time, reducing adhesion and conductivity, which can compromise both rhythm analysis and shock delivery — this is why pads carry hard expiration dates.
• Typical pad shelf life ranges from 2 to 5 years depending on manufacturer and model — confirm the specific expiration on the packaging rather than assuming a generic interval.
• Inspect pad packaging for an intact seal; a broken seal means the gel may have dried out prematurely and the pads should be replaced even if not past the printed date.
• Always replace pads used in an actual resuscitation attempt with a fresh, sealed set immediately.
• Stock at least one spare set of pads with every unit, with expiration dates tracked on a visible log.

Functional and Energy Output Testing

Biomedical engineers should verify defibrillator performance using a dedicated defibrillator/AED analyzer capable of simulating patient impedance loads, consistent with recognized test practices referenced in AAMI DF80 and IEC 60601-2-4 style testing regimes:

These checks mirror recommendations published in biomedical engineering literature, including guidance on defibrillator testing for safety and effectiveness (AAMI, Testing Defibrillators for Safety and Effectiveness, Biomedical Instrumentation & Technology).

Pre-Use Acceptance Checklist for Refurbished Units