Part two of two. Part one, “First 5 Minutes,” covers why the first five minutes back in the room are the most dangerous, and why a thing that’s connected isn’t necessarily working. This is the walkthrough.

The reset, again, in order: Cannula, Power, Oxygen, Water, Sweep and settings, Alarms, Data. Here’s what each one actually catches.

C — Cannula

First, because it’s the only item that can kill in seconds.

Three checks: securement (sutures, clip, and dressing intact), external position (the depth marking at the skin matches your documented number — you should know that number cold), and the site itself (no kinks, no new bleeding).

The fear isn’t only frank decannulation, though that’s catastrophic. The subtler enemy is migration. A drainage or return cannula pulled back during a slide gives you suck-down, chatter, recirculation, or a number of other issues. The external mark can even look fine while the tip has moved. Don’t let a happy pump talk you out of looking. In peripheral VA, “C” is plural, don’t forget the distal perfusion cannula and the limb it’s keeping alive.

P — Power

Both ends. The AC cable into the wall and the cable seated in the machine. Then confirm the indicator that says it’s actually on mains and charging — not just that a plug is in a hole.

Two traps. First, the wrong outlet: use the emergency/backup-power outlets, not a regular one. Second, trusting the battery. The battery is your transport bridge, not your home base. If you don’t restore mains power, the machine runs the battery down silently. It will usually start alarming with plenty of reserve, but you will loose a vote of confidence from the relatives that are sitting in their loved ones room. “Plugged in” with no charging indicator is the false reassurance in its purest form.

O — Oxygen

Two reconnections, not one, and both have to happen. First, the blender on the ECMO cart gets plugged into the wall — wall oxygen and wall air. Then the oxygenator’s gas tubing comes off the transport tank and connects to the sweep flowmeter on the cart, which is fed by that blender, which is now fed by the wall. The whole supply path is wall → blender → flowmeter → oxygenator.

The trap is doing half of it. Plug the blender into the wall but leave the tubing on the tank, and the blender’s live while the patient’s gas is still coming from a cylinder you’ve been draining all trip. As long as the tubing’s on the tank, you’re living on what’s left — and it’s less than you think. A lot of tanks have an alarm that goes off at 500 psi, but you will loose another vote of confidence with the loved ones that are sitting in the patient’s room. Move the tubing onto the wall-fed flowmeter and you’re finally off the countdown.

W — Water (the heater-cooler)

The order matters here, and it’s the one people get backwards. Warm the heater first, then connect it. Power the unit and let it circulate in its own loop until it reaches target temperature, and only then connect the water lines to the oxygenator. Warm to warm.

You have to understand the starting state to see why. We generally don’t warm the patient during transport — they run passive by design, and the heater goes on once we’re back in the room, or in the OR for an extended case. So on arrival the unit has been off the whole time and it’s cold. That’s the expected state, not an exception. And the instinct, when you want warming started fast, is to plug it straight into the oxygenator. That instinct is the trap.

If you connect a cold heater to the oxygenator and then let it warm up, and you’ve plumbed a room-temperature exchanger into the circuit, actively pulling heat out of the patient for as long as the catch-up takes. They were holding steady on passive transport; now you’re cooling them.

This is where pediatrics is unforgiving. A small child has little thermal reserve and a circuit blood volume that’s large relative to their own, so a cold exchanger doesn’t nudge their temperature, it drags it down fast and deep. The consequences stack: coagulopathy in an already anticoagulated patient, arrhythmia, rising oxygen demand, and real distress for a child who can feel every bit of it. It can genuinely shock them. Adults have more buffer, but the principle holds. Get it to temperature, then bring it to the blood.

S — Sweep and Settings

This letter does double duty, and both halves are easy to skip in the rush.

Sweep first, because it’s the killer, and because the letter “O” only got the tubing onto the flowmeter. It did not confirm gas is moving. The flowmeter can sit at zero, or at the wrong number, with the tubing perfectly connected. So come back to it on its own and confirm the sweep is on and set to the right level. You probably eyeballed it during the tubing move; check it again anyway, separately, on purpose. Sweep-off is an emergency that doesn’t announce itself on the console.

Then the rest of the settings, because transport settings persist. You may have run a higher flow during the move or set FdO2 to 100% for the trip. Now the machine is quietly delivering the wrong therapy behind a normal-looking display. Walk the numbers against the order: pump RPM and target flow, sweep rate, blender FiO₂, and heater target.

Settings is the capstone of the “Connected Is Not the Same as Working” idea. It doesn’t ask if it’s plugged in. It asks if it is set to the right number.

A — Alarms

Restore the limits, high and low flow, circuit pressures, and delta-P if you trend it. Un-silence anything you muted for transport. Confirm the air/bubble detector and intervention is turned on.

Alarms come near the end on purpose: they’re the safety net for everything above. If the cannula migrates an hour from now, if the flow drops, pressures change, if power quietly drops to the battery, alarms are what tell you. A silenced or widened alarm means everything you just confirmed has no backstop. You set alarms after you’ve set the values it’s watching, which is why “A” follows “S.”

D — Data

Reconnect the data cable so the console transmits to the chart and to central monitoring.

It’s last for an honest reason: it’s the only item that won’t hurt the patient in the next five minutes. But it isn’t optional. Lose it, and you lose trending, the documentation trail, remote visibility, and alarm routing to the station. Last in priority. Not skippable.

The bottom line

C-POW-SAD is a connection-and-configuration check for the highest-risk five minutes in an ECMO patient’s day. Its job is to defeat the false reassurance of something that’s present but not working. Treat this as a non-negotiable task. Don’t trust the calm console: after a move, the machine looking normal is the beginning of the check, not the end of it.

Learn more

For more practical ECMO articles and study tools, look around on this website LifeSupport.Training and subscribe to this newsletter ECMO 143: AI-Assisted Journey.

I also built AI ECMO Educator, a free-to-use tool that provides evidence-based ECMO and ECPR guidance for ICU clinicians and trainees, covering physiology, cannulation, anticoagulation, circuit management, and troubleshooting. It draws from sources such as ELSO, PubMed, AmSECT, and leading centers.

Disclaimer

This content is for educational purposes only and does not replace clinical judgment, institutional protocols, or consultation with your ECMO team.

Part one of two. Part two walks through CPOW-SAD letter by letter.

Transport gets most of the attention: the packing, the battery math, the oxygen tank, the elevator, the door frames, the trip there and the trip back. And it should. Moving an ECMO patient is one of the riskiest things we do.

But I have learned to respect the moment right after transport just as much.

Back in the ICU room. Back from CT. Back from the OR. The patient is settled. The team is busy. Everyone exhales a little. That exhale is the problem. The first five minutes after a move may be the easiest time to miss a preventable error, because everything looks like it is back where it belongs.

So I run a reset every time. The mnemonic I use is CPOW-SAD:

• C - Cannula

• P - Power

• O - Oxygen

• W - Water

• S - Sweep and settings

• A - Alarms

• D - Data

That sequence is not random. Secure the patient. Restore the supplies the machine depends on. Confirm the machine is running at the right settings. Arm the safety net. Make sure the data is transmitting. Part two will walk through each letter in detail. This first part is about the idea underneath the mnemonic.

The main idea: connected is not the same as working

If you remember one thing, remember this: connected is not the same as working.

After a move, the danger is not always that something is missing. Often, the danger is that something is present but not doing its job. The power cable may be in the wall, but not seated in the machine. The gas tubing may be connected, but the flowmeter may still read zero. The heater-cooler lines may be hooked up, but the unit may still be cold. The cannula may still be sutured, but it may have shifted during the slide from bed to table, or table to bed.

Everything looks attached. The console looks calm. That is the trap.

CPOW-SAD is not a “did I plug it in?” list. It is an “is it actually functioning?” list. Every letter asks the harder question. Not just, “Is it there?” but “Is it secure? Is it powered? Is gas actually flowing? Is water warm and circulating? Are the settings back where they should be? Are the alarms armed? Is the data transmitting?”

Why this matters after transport

There is a reason this happens after transport. The team is task-saturated. Everyone is trying to get the patient settled. Sources are being switched from portable to wall. Cables are being moved. Tubing is being reorganized. The patient has just been moved from one surface to another, and anything taped, sutured, clipped, connected, or positioned can shift.

That combination matters: high workload, physical movement, source changes, a quiet console, and a team that thinks the hard part is over.

That is exactly when a reset helps. A pump can be spinning at full flow with the gas off. A cable can sit in the wall and charge nothing. A circuit can look perfect while two centimeters of cannula migration changes everything. So I do not trust the calm console. I walk it.

Do not leave the room SAD

There is a hook inside the hook. The front part is familiar: CPOW. Cannula. Power. Oxygen. Water. Those are the visible things. They are easier to remember because they feel physical.

But the back half matters just as much: SAD. Settings. Alarms. Data.

Those are the ones I see skipped most often, because they are less visible. Nothing falls on the floor when you forget them. The patient may simply drift in the wrong direction, unwatched or undocumented. That is why the tail does its own work: do not leave the room SAD.

Before I leave, I want settings correct, alarms armed, and data flowing.

A shorter version like POW is easier to remember, but look at what it drops: cannula and sweep. Those are high-stakes checks. Shorter is not always safer.

Saying it out loud

When a family member is at the bedside, I will sometimes run CPOW-SAD out loud. Not dramatically. Just calmly: “I’m checking the cannula. Now power. Now oxygen. Now water. Now sweep and settings. Now alarms. Now data.”

That does three things. First, it reassures them. They see deliberate care instead of silent activity around tubing and machines. Second, it steadies me, because explaining the steps gives my own focus somewhere to go. Third, it forces honesty. You cannot say “power is on AC and charging” out loud while staring at a battery icon and not catch the problem.

The person at the bedside becomes part of the check. That is not bedside manner added at the end. It is part of the method.

The point

For me, CPOW-SAD is less about memorizing letters and more about respecting the first few minutes after a move.

That is when small misses hide in plain sight.

A cable can be present but not charging. Tubing can be attached but not flowing. A cannula can look secure but still move. So I try not to rush that moment. Connected does not mean it is working until I confirm it.

Next: Part two, CPOW-SAD letter by letter. What each check actually catches at the bedside.

Learn more

For more practical ECMO articles and study tools, look around on this website LifeSupport.Training and subscribe to this newsletter ECMO 143: AI-Assisted Journey.

I also built AI ECMO Educator, a free-to-use tool that provides evidence-based ECMO and ECPR guidance for ICU clinicians and trainees, covering physiology, cannulation, anticoagulation, circuit management, and troubleshooting. It draws from sources such as ELSO, PubMed, AmSECT, and leading centers.

Disclaimer

This content is for educational purposes only and does not replace clinical judgment, institutional protocols, or consultation with your ECMO team.

To understand how blood moves through the heart, we can number the valves in the order in which the blood passes through them as it travels from the venous to the pulmonary and then to the arterial side.

The Sequential Order of Heart Valves

1. Tricuspid Valve: The first valve. It allows deoxygenated blood to flow from the Right Atrium into the Right Ventricle. Tri=3 leaflets for the valve

2. Pulmonary Valve: The second valve in the sequence. It opens to allow blood to be pumped from the Right Ventricle into the Pulmonary Artery on its way to the lungs. There are 3 leaflets for the pulmonary valve.

3. Mitral Valve (also called the Bicuspid Valve): After the blood is oxygenated in the lungs, it returns to the Left Atrium and passes through this third valve into the Left Ventricle. Bi (cuspid) = 2 leaflets for the valve.

4. Aortic Valve: The final valve. It opens to allow oxygen-rich blood to leave the Left Ventricle and enter the Aorta, which distributes it to the rest of the body. 3 leaflets for the aortic valve.

Two Quick Memory Tricks

Here are a few solid memory tricks to help you remember the right-to-left valve sequence

(Tricuspid → Pulmonary → Mitral → Aortic):

Bonus Valve Information

The Rule of Three

3 valves have 3 leaflets:

• Tricuspid

• Pulmonary

• Aortic

This design allows a wide opening for flow and tight closure under pressure.

The Mitral Exception

The Mitral valve has 2 leaflets.

It sits on the left side of the heart and handles the highest pressures (transvalvular).

It is supported by chordae tendineae and papillary muscles, which prevent it from prolapsing back into the left atrium.

Why This Matters at the Bedside

If you understand the sequence, you can troubleshoot faster.

Example:

• Pulmonary edema? Think Mitral or left side problem

• High CVP and congestion? Think Tricuspid or right side problem

• No pulse pressure on VA ECMO? Think Aortic valve not opening

Start with flow. Then find where it’s blocked or leaking.

Learn more

If you want more ECMO breakdowns like this, make sure you are subscribed to this newsletter, ECMO 143: AI-Assisted Journey. I’ll keep sharing what I’m learning along the way.

You can also use my free Custom GPT, AI ECMO Educator, an evidence-based ECMO and ECPR educator for ICU clinicians and trainees, covering physiology, cannulation, anticoagulation, circuit management, and troubleshooting. Sources include ELSO, PubMed, AmSECT, and leading centers. Version 5.2 (2/21/26) | Supports 50+ languages.

The Truck Analogy

When a patient isn’t improving, it’s easy to chase the PaO₂.

But oxygen delivery depends on three things.

Think of hemoglobin like a truck carrying oxygen to tissues.

The Three Levers

1. Load the trucks → increase saturation (SaO₂)

• FiO₂ / FdO₂

• Oxygenation

2. Add more trucks → increase hemoglobin (Hgb)

• Transfusion

• Oxygen-carrying capacity

3. Move them faster → increase flow (Q)

• ECMO flow (see note below)

• Cardiac output

Quick Bedside Check

If oxygen delivery is low, ask:

• Is saturation adequate?

• Is hemoglobin adequate?

• Is the flow adequate?

Look at the problem with an open mind and fix it.

Common Mistake

Low PaO₂ → increase FiO₂

Helps—but only to a point.

Beyond that:

• Minimal gain in delivery

• Rising PaO₂ may be harmful

Think: Hb + Flow + Saturation—not PaO₂ alone.

Important Note: VV vs VA ECMO Response

Takeaway

Saturation + Hemoglobin + Flow = Oxygen Delivery

Don’t chase PaO₂ in isolation.

Learn More

Subscribe to LifeSupport.Training to receive updates and read the ECMO 143: AI-Assisted Journey newsletter, along with the new ECMO Tools section.

You can also use AI ECMO Educator, a free Custom GPT designed to support ECMO and ECPR learning for ICU clinicians and trainees.

Educational content only. Follow your institutional protocols and clinical judgment.