Electrocardiogram (ECG) Examination: Understanding the Heart's Electrical Activity

Introduction

An Electrocardiogram (ECG) is a diagnostic procedure used to assess the electrical activity of the heart.

What is an ECG?

An ECG, short for electrocardiogram, is a comprehensive examination that involves placing probes on a patient's body to monitor the electrical activity of the heart.

Reasons for Performing an ECG

An ECG is conducted when:

• There is suspicion of abnormal heart rhythms or arrhythmias
• A patient is critically ill, and the impact of their illness on the heart needs to be assessed
• The effect of medication on heart function needs to be evaluated

The Defibrillator and ECG

The defibrillator is the machine used to perform an ECG. It consists of various components, but our focus will be on the ECG part.

Three-Lead ECG

The three-lead ECG uses limb leads, which are placed on specific areas of the patient's body. The limb leads are labeled as follows: R (Right), L (Left), F (Foot), and N (Other Foot).

Preparing the ECG Machine

Before conducting the ECG, the machine needs to be prepared:

• Attach the appropriate electrodes to the machine
• Ensure the machine is calibrated by using dots and electrodes

Using Electrodes

Electrodes are available in different brands. Some are designed for sensitive skin, while others are standard. They come in packs and can be easily clicked into place on the patient's body.

The Importance of a 12-Lead ECG

A 12-lead ECG provides a more comprehensive assessment of the heart. Additional dots and leads are required to perform a 12-lead ECG, which offers 12 different views of the heart.

Placing Chest Leads

Chest leads, also known as precordial leads, are labelled C1, C2, C3, C4, C5, and C6. They are placed on the patient's chest to provide specific views of the heart.

Ensuring Proper Adhesion

It is crucial to ensure that the electrode pads stick properly to the patient's chest. Excessive hair or sweat can hinder the adhesion. The gel on the electrode pad facilitates electrical conduction for accurate ECG results.

Checking the Validity of Dots

Expired dots may have insufficient gel, resulting in poor trace quality. Always check the expiration date of the ECG dots to ensure optimal performance.

Connecting the Leads

Attach the dots to the patient in the desired order. Connect the 12-lead plug to the 3-lead box, enabling the display of a complete 12-lead ECG.

Interpreting the ECG Results

The defibrillator's display shows the 12-lead ECG traces, allowing for analysis and interpretation of the heart's electrical activity.

Printing the Results

When printed, the ECG report will display a full 12-lead ECG.