The 3 lead ECG

cardiac arrest ecg education emergency management heart rate Oct 23, 2023

Did you know that cardiac arrhythmias occur in more than 80% of patients under anaesthesia? 🫣

The standard method of monitoring 🫀rhythm during anaesthesia is using a 3-lead ECG. This method is easy to apply but provides less information than a 5-lead or 12-lead ECG.

The 3-lead ECG allows you to display lead I, II or III on the monitor. Lead II is the default on most anaesthetic machines. It is the best (of the 3) at detecting arrhythmias because it displays the most obvious P wave (due the direction of the lead placement).

Even though the 3-lead ECG isn’t perfect, it does allow you to work through these 6 questions that will help keep your patient safe:

1️⃣ What is the heart rate?
2️⃣ Is the rhythm regular or irregular?
3️⃣ Is one P wave present for each QRS?
4️⃣ Is the QRS normal?
5️⃣ Is the rhythm associated with a change in blood pressure?
6️⃣ Does the rhythm require treatment?

If you can learn how to scan the monitor, answer these 6 questions, and communicate with your anaesthetist… your patient has just become safer! 👏👏

Remember, ECG only shows you the electrical activity of the heart. ⚡️

It does not indicate a normal blood pressure or cardiac output! There are multiple sources of error, and it’s important that you know how to tell the difference between arrhythmia and artifact. ☝🏻

Check out Lesson 3 of the Starter Course to learn more. You can also check out the educational section of our bio for more information. 🤓

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Improve safety ✅


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