Wet Chest, Old Patch, No Shock Advised
You are called to a community gym where a 62-year-old man collapsed during a basketball game. Bystanders have been doing chest compressions for about four minutes. On arrival the man is unresponsive, not breathing, and has no palpable pulse. A second responder brings the AED. The patient is on a wooden court, his shirt is soaked with sweat, and he has a nitroglycerin patch on his upper chest and a pacemaker scar below his left collarbone. The bystander compressions are shallow and fast, about 130 per minute. Adult AED pads are on hand. Your partner is still bringing the airway kit and suction from the truck.
1. The AED is in your hands and the chest is wet, patched, and has a pacemaker. What do you do before and while applying the pads, and why does each step matter?
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Order of operations - do not let prep become a delay:
- Keep compressions going while you prep. Nothing you do to the chest is worth a long pause.
- Wipe the chest dry with a towel or gauze. Sweat is conductive and can bridge the pads, causing arcing and a burn, and it weakens the pad-to-skin contact the AED needs to read the rhythm.
- Remove the nitroglycerin patch and wipe the residue away. The patch can block current and can also transfer drug onto rescuers' gloves - wear gloves and dispose of it.
- Place the pads at least 1 inch from the pacemaker generator (the scar below the left collarbone). Do not place a pad directly over the device - it can block the current from reaching the heart and can damage the device.
- Bare, dry chest, pads firmly pressed down, one to the upper right chest and one to the lower left side.
Then: clear everyone, let the AED analyze, and follow its prompts. The single most important rule is that prep time is compression time - keep hands on the chest until the moment of analysis.
2. The AED analyzes and states, no shock advised. What does that mean, and what do you do next?
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It means there is no rhythm this device is designed to shock - not that the resuscitation is over.
- The AED only shocks VF and fast VT. A no-shock message means the rhythm is most likely asystole or PEA (or a very fine VF the device cannot read).
- Neither asystole nor PEA responds to a shock. The treatment is high-quality CPR, ventilation, and finding a reversible cause.
Immediate actions:
- Resume chest compressions right away - the pause should be seconds, not a discussion.
- Leave the pads on. Do not peel them off; the device will reanalyze on its own schedule.
- Ventilate with the BVM and high-flow oxygen as soon as your partner arrives - 30 compressions to 2 breaths.
- Continue for about 2 minutes, then let the AED reanalyze. Repeat the cycle. A rhythm can change in either direction.
- Do not stop to reassess a pulse for a prolonged period; brief checks only when the device or protocol directs it.
Reassure bystanders and keep the compressor rotating - fatigue destroys compression depth within a couple of minutes.
3. Looking at the bystander CPR, what specifically do you correct, and how do you keep quality up over the next 10 minutes?
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What is wrong with what you see:
- Too fast at 130 per minute. Target is 100-120. Faster often means shallower.
- Shallow depth. Target is at least 2 inches in an adult; let the chest come all the way back up between compressions (full recoil) so the heart can refill.
How to fix and sustain it:
- Take over or coach on the spot - rate and depth are the two things a rescuer can actually control.
- Rotate compressors every 2 minutes, timed with AED reanalysis so you do not create an extra pause.
- Minimize interruptions. Pad placement, analysis, and ventilations all cost perfusion; keep each pause under about 10 seconds.
- Position your body - shoulders over hands, arms straight, hard flat surface. The wooden court works in your favor.
- Watch for the feedback loop getting worse - as rescuers tire, depth drops first, then rate climbs.
Quality CPR and early defibrillation are the two interventions that change survival in out-of-hospital cardiac arrest. Everything else is support.