The first ten days after sternotomy run on their own protocol. The arrest is witnessed, monitored, and usually caused by something a hand or a wire can fix, so the first minute goes to the rhythm rather than to compressions and epinephrine.
Read the rhythm before anyone touches the chest.
Three sequential shocks, delivered inside one minute, before external compressions.
Epicardial wires connected: DDD at 80–100/min, maximum atrial and ventricular output.
Capture means an arterial waveform. Spikes on the monitor prove nothing.
If the patient is paced, switch the pacer off first. Spikes can hide fine VF.
True PEA: exclude airway and tension pneumothorax fast, then prompt resternotomy.
Falling pressure with rising filling pressures is an obstruction until proven otherwise.
The pre-arrest picture in early tamponade is low MAP, rising CVP, narrowing pulse pressure, and falling cardiac output. Chest tube output that drops at the same time is not reassurance. It often means the tubes have clotted and the blood is collecting around the heart.
Postoperative tamponade is often regional. In a series of 510 cardiac surgery patients, 9 of the 10 tamponades had atypical findings: selective compression of one or two chambers by loculated clot, and in 6 cases no anterior fluid at all.
Echo is weakest when you need it most. In the first 24 hours after surgery, echocardiography had a positive predictive value of 58% for tamponade confirmed at re-exploration (AUC 0.64). A reassuring early echo does not end the question.
Escalating vasopressors in this state treats the number while the cause compresses the heart. The response is the surgeon and the operating room, before the arrest makes the decision.
A paced patient with organized complexes and no pulse may be in fine VF underneath the pacing artifact. The STS protocol has the pacer switched off at the start of a PEA arrest so the native rhythm can be seen. If it is VF, it goes down the shock pathway.
Once VF is excluded, true PEA after cardiac surgery is a mechanical problem until shown otherwise.
| Cause | What resolves it |
|---|---|
| Tamponade | Resternotomy and evacuation |
| Hemorrhage / hypovolemia | Volume, then surgical control |
| Tension pneumothorax | Decompression; check both pleural spaces |
| Airway catastrophe | ETT position and patency, ventilator check, FiO₂ 1.0 |
| Graft, valve, or other surgical failure | Resternotomy |
Running the full Hs and Ts list has a cost here. Five mechanical causes, checked in seconds, cover most of what kills these patients.
The protocol does not forbid compressions on a fresh sternotomy. It defers them for up to one minute while the faster definitive therapies are tried, then starts them. External compressions can crack a fresh repair or tear a graft, which is why the minute matters, but cerebral perfusion matters more once that minute has passed.
The STS consensus starts from the position that external massage is ineffective in tamponade and hypovolemia. That is the reason for the five-minute resternotomy target, and for preferring internal massage once the chest is open.
The reasoning is mechanical. If the arrest is from tamponade and the chest is opened two minutes after a 1 mg bolus, the drug is still in the circulation when the heart starts filling again. The result is extreme hypertension across fresh anastomoses and suture lines.
This is a restriction, not a ban. Smaller titrated doses remain available on a senior decision. Amiodarone 300 mg follows the third failed shock in VF.
Assigned before the arrest, rehearsed as a team.
Compressions once the first minute has passed.
Tube position, ventilator, both chest drains, pneumothorax.
Shocks, wires, pacing box at maximum output.
Runs the algorithm and calls resternotomy.
Manages infusions, gives amiodarone, holds routine epinephrine.
Equipment, extra staff, keeps the room clear.
Two or three trained people who gown, glove, and open the set at once. In practice they may be the clinicians already in the room, with the surgeon still on the way. Assign it on every shift.
Emergency resternotomy remains part of the arrest protocol through the tenth postoperative day. After that, adhesions make reopening slower and more dangerous, and the balance shifts back toward standard ALS. Patients who had cardiac surgery without a sternotomy are covered by a separate STS pathway.
The equipment lives in the ICU. Five minutes is not enough time to fetch a sternotomy set from the operating suite. The set, the wire cutters, and internal paddles belong at the bedside unit.
The 2025 AHA guidelines include arrest after cardiac surgery as a special circumstance in Part 10. The STS document remains the most detailed protocol. Training is available as CSU-ALS (csu-als.org).