External Defibrillators: MedSun Small Sample Survey Summary
MedSun: Newsletter #66, November 2011

Survey Topic: External Defibrillators - Summary of Responses
Year Conducted: 2010

External defibrillators are critical life-saving devices that are used successfully hundreds of times each year to treat patients experiencing sudden cardiac arrest. The FDA recognizes the important life-saving benefits of external defibrillators and that users trust they will operate properly. It is unlikely that an external defibrillator will malfunction however, the FDA is aware of infrequent problems associated with external defibrillators that impact patient safety.

This survey was an effort to learn about experiences with external defibrillators and to gain a better understanding of the clinical perspectives of these devices and suggestions for improvement. The survey was conducted by phone with nine individual healthcare professionals from nine MedSun facilities. Survey respondents included clinicians from areas such as the emergency room, intensive care unit, and clinicians who are also members of the code or rapid response team. Respondents also included some biomedical engineers and emergency medical technicians (EMTs). The EMT respondents work with an ambulance service affiliated with a MedSun facility. The purpose of interviewing EMTs was to discuss their experiences specifically with the use of automatic external defibrillators (AEDs). The information that follows is a summary of responses.

The Philips HeartStart XL and MRx, Medtronic Lifepak Models 12, 15, and 20, and the Zoll M Series were cited as the primary brands of external defibrillators used by respondents. All respondents believe that the defibrillators they use will perform as expected when needed. Most said they are happy with their current external defibrillator model, and once hospital staff is properly trained and familiar with the devices, they also believe the devices are easy to use.

One clinician said they prefer their particular model of defibrillator for transport because it weighs less, which is especially important for transport by helicopter, and because the data on the screen remains stable during transport. However, another respondent said they avoid using this lighter weight defibrillator because it only runs on battery and if there is no electricity available during transport, treatment cannot be delivered. Other respondents did not say there is a particular brand they avoid using.

The function mode used most often on these devices by respondents is the manual mode. A few use a combination of manual and monitoring modes. The pacer and AED modes are rarely used. Usually, the mode selected depends on the patient’s condition.

Nearly all respondents report there are defibrillator design features that affect functionality. A primary issue is the large size of most defibrillators. Respondents think these devices tend to be too cumbersome in size and weight and would like to see them lighter and more portable. This is especially problematic when defibrillators are needed for transporting patients within and also outside of the hospital setting.

Those who use external defibrillators think having different cables for pads and paddles is confusing and would like to see that changed. Some cables are more user friendly than others because they are easier to plug-in and remove. Another user said he would like to see regulation for universal pads and paddles that all connect the same way. Another criticism of defibrillator design is the large pouches on each side of some units that make it difficult for users to reach the cables and cords quickly. Respondents also said they would like to know how to sterilize external paddles because in trauma cases there may be contact with blood and body fluids. One manufacturer does not recommend sterilization of paddles because it causes the material to degrade but do not offer users any alternative sterilization solutions.

Another suggestion involving a design change is to make defibrillators more modular so hospital staff can easily remove parts or accessories that aren’t needed at the time. Also, a better way to secure the defibrillator in an emergency vehicle is needed. Currently, some EMTs can only use a passenger seatbelt or a strap to hold the defibrillator in place in a vehicle. They would also like device handles that are more rigid to withstand stress, pull, and torque. Another design feature that would be particularly helpful to have when transporting patients is pulse oximetry. However, it was noted that some of these suggested changes may affect having a model that is lightweight.

Defibrillator accessories may include external pads, paddles, electrodes and batteries. Most users report that these accessories work well. Other users had suggestions for improvement. One said it would be nice if electrodes were double packaged by all manufacturers to prevent the conductive gel from drying out too quickly. One user would like longer and more durable wires, as well as longer lasting batteries. Several respondents would like power cords that are more secure because they can easily come loose during transport. Some users said cord dislodgment is a design problem they would like to see improved and suggest a lock or snap feature for the cord to prevent dislodgement. When discussing batteries, respondents report failures occur most often because the defibrillator was not plugged-in by staff when not in use.

Most respondents said they have not seen problems or adverse events with the use of external defibrillators. Any problems they do see are usually the result of use error or physical damage to the device from being dropped or bumped by other devices. In case of defibrillator failure, all respondents said their facilities have backup devices. The number of backup devices available in hospitals varied from hospital to hospital and by type of patient unit. One respondent said that on their ambulances there are no backup devices and if the defibrillator failed they would have to continue CPR with continuous assessment of the patient.

All said that their hospital clinical engineering departments have preventative maintenance schedules for external defibrillators. Maintenance includes following manufacturer guidelines and having clinical engineering inspect the devices on a quarterly or semi-annual basis. Also, all respondents said that defibrillators are checked by nursing staff at least every 12 to 24 hours to make sure they are working. Several clinical engineering departments report they change defibrillator batteries routinely every two years. One user said they would like better education from the manufacturer on the automatic “midnight check” performed by some devices. This task caused confusion at one hospital because staff thought they did not need to perform additional safety tests because of the device’s automatic self-test.

Training on the use of external defibrillators is mandatory in all of the facilities involved in the survey. Many require staff certification in ACLS or BLS every two years. Additional device training occurs at several facilities and includes mock codes, hospital skill days for staff, and other hands on approaches. Written materials, online training, power point presentations, and other texts are also part of the training courses. It was noted that transport nurses tend to be savviest with external defibrillators because they use many different models or brands and can switch use among various devices without difficulty.

Reviews of external defibrillator user manuals are mixed. One user said they don’t need to reference the manual. Some thought their manuals are small and easy to use while others said their manuals are too large and cumbersome. Some manuals are kept on the crash cart with the defibrillator. Most respondents say they don’t refer to the user’s manual and some haven’t seen the manual at all. One user reports that manuals are often too difficult and too technical to understand by most staff. Some don’t use the manual because they’ve developed their own checklists and “cheat” cards for staff who are less familiar with the devices and who are infrequent users.

When respondents need information about external defibrillators they go to several sources. Most cited the American Heart Association (AHA) as a primary source for defibrillator information. EMT trade magazines, conventions, in-service training, and word of mouth are also utilized as sources for information. A few respondents also said they contact the manufacturer’s representative and website when necessary. Several also cited FDA as being a valuable source of information to determine which manufacturers are having device issues.

When external defibrillators are recalled by the manufacturer most respondents said that if they have the device in their facility they take the manufacturer’s recommended action. Usually, these recalls are initially handled by the clinical engineering department, materials management, or both. These departments filter information to clinical managers, clinical educators, and charge nurses. Respondents noted that some vendors will come on site to take care of problems with their defibrillators. Recall information is also shared within the hospital by phone or email. Several utilize web-based recall systems such as RASMUS and ECRI. Several respondents report that it’s a challenge to keep up with recalls when they occur outside of the schedule for their preventative maintenance. Most respondents did say, however, that the rate of servicing for defibrillators compared to other devices was relatively low.

Respondents had several opinions about what they would do to make external defibrillators better. In general, they would prefer if the devices were more standard across manufacturers. One respondent would like external defibrillators to be less complicated and have less functions. They think it is critical that the basic functions are very straightforward. Other comments on improvement centered on device design and accessories including lighter weight, better durability, retractable cables, cord locking features, universal pads and paddles, and increased duration of conductivity of the electrode gel. Despite comments on how to improve external defibrillators, one respondent believes most of their problems revolve around uncharged batteries and human factor issues.

Overall, survey respondents believe that the external defibrillators in their facilities perform as expected when needed but would like to see improvements in design and functionality that assist them in performing successful defibrillation and resuscitation of cardiac arrest victims.

Special Studies and Surveys are two of many tools the Agency is using to evaluate the public health impact of the potential problems associated with the use of medical devices. Additionally, FDA continues to receive adverse event reports from its Medical Device Reporting program. FDA will also continue to make use of the literature and other published information. FDA scientific, medical, nursing and engineering staff are made aware of the survey results as needed. If FDA believes there is a significant risk of adverse events as noted from the survey, it will combine those results with data gained from the other sources. FDA will work with the manufacturers and health care professional organizations to make important information known to the clinical community. Additionally, FDA continues to work with manufacturers to ensure the development, testing and promulgation of methods for reducing the risk associated with these devices and to minimize the complications from adverse events that may occur in the course of normal usage. If the results of any survey raise serious concerns about the safety of these devices, FDA may convene an Ad Hoc group of clinical and manufacturing representatives to discuss further actions..

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