Office gym: agonal gasps, a pacemaker and a single set of pads
At 09:15 in a small office gym, a 54-year-old manager collapses mid-stride on a treadmill and does not get up. You are one of two trained first aiders on site; eight other staff are in the room. She is unresponsive to shouting and to a shoulder squeeze. You see occasional slow, noisy gasps at roughly six a minute. There is no trauma and no blood. You notice a hard bump under the skin just below her left collarbone, consistent with an implanted pacemaker, and a nicotine patch on her upper arm. Her chest and sports top are soaked with sweat. A colleague brings the site AED: one set of adult pads, a razor, and a towel. The site's emergency action plan requires 999 to be called first. Someone has already dialled and is on the line. The ambulance ETA is nine minutes.
1. Is this a cardiac arrest? Justify your answer and state exactly what you and your colleague do in the first 60 seconds.
Read the worked answer
Yes. The two criteria are unresponsiveness plus absent or abnormal breathing, and both are met. The slow, noisy gasps at six a minute are agonal breathing - a brainstem reflex, not respiration. It is the most common reason bystanders delay CPR: the casualty appears to be "breathing a bit". She is not.
First 60 seconds:
- Confirm unresponsiveness with a shout and a shoulder squeeze, nothing more elaborate.
- No pulse check. Lay rescuers should not spend time feeling for a carotid pulse; it is unreliable and wastes the first minutes.
- Open the airway, look in the mouth, remove nothing unless it is visible and loose.
- Start chest compressions immediately: centre of the chest, heel of hand, 5–6 cm deep, 100–120 per minute, full recoil, 30 compressions to 2 ventilations. Switch compressor every two minutes.
- Send the colleague with the AED to the other side of the chest, and put the phone on speaker so the call-taker can coach and time the response.
- Delegate: one person to the gym door to meet the crew, one to clear the equipment.
Starting compressions before the AED arrives is the single most time-critical action.
2. Describe how you prepare the chest and place the pads, taking account of the pacemaker, the patch, the sweat and the single set of pads.
Read the worked answer
Prepare the chest first, because each of these will cause a poor electrical contact and a false "check pads" prompt:
- Dry the chest firmly with the towel or her top. Wet skin causes the current to arc across the surface rather than through the heart, and the pads will not stick.
- Remove the nicotine patch and wipe the tacky residue off the skin. Transdermal patches can interfere with pad adhesion and have been linked to arcing and small skin burns during defibrillation.
- Keep at least 8 cm clear of the pacemaker generator, which sits under her left clavicle. Place the right pad below the right clavicle and the left pad in the mid-axillary line at nipple level, clear of the device. If the device encroaches on that position, use an anterior–posterior placement. Never place a pad directly over the generator.
- Do not spend time shaving with a single set of pads. Press the pads down firmly and evenly by hand. Shave only if the AED prompts "check electrodes" - and even then, use the razor quickly and press the pads back down.
Then: shout "stand clear", make sure no one is touching her, let the AED analyse, and follow its voice prompts. Do not interrupt compressions for more than about ten seconds at any point.
3. The AED advises one shock, delivers it, then announces "no shock advised". She gasps and her arm jerks. What now?
Read the worked answer
Resume chest compressions immediately - do not wait, do not re-check a pulse, and do not pause to interpret the gasps. A gasp or a jerk in the seconds after a shock is a common muscular or reflex response and is not evidence of a return of circulation. The rhythm is not shockable at this moment, but that does not mean the heart is pumping.
Continue 30:2 for two minutes (the AED will prompt you), then let it re-analyse. Minimise every interruption. Leave the pads attached and the AED on for the whole resuscitation - the rhythm can change back at any time, and the machine needs to be there for the next analysis.
The moment to stop compressions is when she shows normal breathing, not agonal gasping: regular quiet breaths, a improving colour, and movement that is purposeful. If that happens, place her in the recovery position on her side, keep the pads on and the AED connected, keep monitoring her breathing continuously, and hand over the timings to the paramedics.
Tell your colleague the reasoning explicitly - "gasping is not breathing, we keep going" - so that nobody stops CPR on the strength of a reflex.