An Automated External Defibrillator (AED) is a life-saving device that uses electrode pads to deliver an electrical shock to a person experiencing sudden cardiac arrest. These pads are the direct interface between the AED and the patient, transmitting the electrical current and allowing the device to analyze the heart’s rhythm. A functional AED relies on having current, non-expired pads that can properly conduct the necessary energy. Maintaining the readiness of the AED, particularly the pads, is a necessary component of emergency preparedness and ensures the device will work as intended when seconds matter.
Why and When Replacement is Necessary
Replacement of AED pads is required for two reasons: following any instance of use and upon reaching their expiration date. Pads are strictly single-use items and must be replaced immediately after deployment, even if no electrical shock was administered. The adhesive and conductive elements are compromised once the protective seal is broken and they are applied to a patient.
The primary trigger for replacement is the expiration date printed on the pad packaging, which typically falls within an 18 to 30-month window. Pads contain a conductive adhesive gel that ensures firm skin contact and allows the electrical current to pass effectively. Over time, this water-based gel degrades, dries out, and loses conductivity and adhesion, making the pads unreliable. Using pads past this date risks an ineffective shock, which significantly reduces the patient’s chance of survival.
Preparing for Pad Replacement
Before beginning replacement, users must confirm they have the correct new pads, as there are important distinctions between pad types. Adult pads are intended for individuals eight years or older or those weighing more than 55 pounds. These pads deliver a higher energy electrical dose suitable for a larger body mass.
Pediatric pads, often referred to as attenuated pads, are designed for children under the age of eight or weighing less than 55 pounds. These specialized pads incorporate a mechanism, often a current-limiting resistor, to reduce the energy output to a lower, safer dosage appropriate for a child’s heart.
Using the wrong pad type can be dangerous. Adult pads may deliver too powerful a shock to a child, while pediatric pads may be ineffective on an adult. Always ensure the unit is powered off or disconnected from the power source according to the manufacturer’s instructions before opening the AED compartment.
Step-by-Step Procedure for Pad Installation
The first action in the physical replacement process is to locate and detach the connector for the old pads from the AED unit. This connector is usually a plug-in cable or a cartridge that fits into a designated port on the device. Once the old connector is removed, the used or expired pad package can be safely discarded, often treated as electronic waste due to the presence of electrodes.
Next, unpack the new replacement pads and identify the connector end. Insert this new connector into the designated port on the AED unit, pushing it firmly until a secure connection is confirmed, sometimes indicated by an audible click. The cable should be neatly routed and the sealed pad packaging secured inside the AED case or compartment, making sure the cable is not pinched by the closing lid. The pads must remain sealed in their protective foil packaging until they are needed for an actual rescue.
Post-Replacement Readiness Check
The pad replacement process is not complete until the AED confirms its rescue-ready status. After installing the new supplies, the user should power the AED back on, if necessary, and allow the device to run its internal self-test. Most modern AEDs perform this self-diagnostic check automatically to verify the new pads and other components are functioning correctly.
The visual status indicator, typically a light or screen icon on the device’s exterior, is the final confirmation of readiness. A green light or an “OK” symbol indicates that the AED is fully operational and prepared for use. If the indicator shows a red light or a warning symbol, the user must consult the device’s manual to troubleshoot the issue immediately. Expired or used pads should be disposed of promptly, often through an electronics recycling program, or as biohazard waste if contaminated with blood.