During the course of a game or practice, whether in the stands, restroom, or parking area, someone on site may suddenly have one of the many possible serious injuries or health problems that warrant "immediate" emergency care attention, i.e., an "immediate" call for EMS help while first aid attentions are being applied. Readiness for these actions is enabled by advance planning and preparation by League and Ballpark owners for each of the various ball parks in the program, utilizing known persons (e.g., coaches, park staff, parents, and/or volunteers) who are trained as first responders for CPR and other first aid attentions. Actually all team and staff personnel should be trained and stay trained in minimal first aid including CPR and AED use "just in case."
AEDs become relevant when the emergency appears to be a sudden cardiac arrest (e.g., spectator, coach, umpire) or a batter's heart going into fibrillation from being hit in the chest by a pitch (1). "Immediate" is now considered to be six minutes or less (preferably 3 or less) from onset. Ideally, this means that either the EMS team can arrive with their equipment "immediately" from the time of onset (not after a telephone call which generally takes 2-4 minutes) or the ballpark has a maintained AED in one or more convenient/strategic locations that could be obtained "immediately," preferably by a pre-designated someone with experience in its use. Whichever, immediate CPR should be initiated by team or staff personnel and continued until an AED arrives and is applied.
It is also important to perform regular drills at various locations throughout the ballpark, in addition to undergoing regular required recertification.
That stated, the 2005 American Heart Association (AHA) guidelines for emergency cardiovascular care directed a change in AED shock technology, which required recall or related adjustments to AEDs (2). Make sure your AED is up-to-date. Look for a manufacturer's tag or sticker on the AED reading "GUIDELINES 2005" (or similar wording). If not present, contact the manufacturer for instruction on reprogramming or replacement. Also regularly check that the AED is in working order and that the chest pads are current and have not expired.
Leagues should in addition be conscious of what is stated or absent within the leases they are asked to sign for the use of their ballparks as to whose responsibility it is for first aid/medical attentions to persons attending or participating in the League's program. Decisions as to purchasing, locating, maintaining, and trained use of AEDs requires advance planning by someone, and preferably documented for easy reference. Check local and state laws for any requirements pertaining to the purchase, training and use of AEDs.
(1) "What is Commotio Cordis in Baseball?", USA Baseball Statement, August 2003.