Electrocardiograms (ECGs) and cardiac monitors

Equipment
Method
Pitfalls

• ECG machine
• Adhesive electrodes
• Razor

[back to top]

• Explain to the patient what you are about to do.
• Attach the electrodes to the skin in the positions shown (Fig. 8). You will need to shave hairy areas to get a good contact. Note that accurate placement is important; having the chest leads in the wrong place can lead to an anterior myocardial infarction (MI) being diagnosed as an inferior MI!
• Turn on the ECG machine. Make sure that the power lead does not cross the electrode leads.
• Enter the patient details if required.
• Make sure that the FILTER button is on.
• Take the ECG (usually by pressing a button marked 12 or auto).

Fig. 8 Placement of ECG chest leads.

[back to top]

Missing tracings: check all the lead attachments and replace any electrodes that are not adhering well. Twist the leads within the attaching clips to ensure that the leads are not pulling the adhesive pads off the patient

Wandering baseline/irregular baseline: repeat the tracing, asking the patient to relax and stay still. If this fails, attach the limb leads to the shoulders and hips; this cuts down on interference from limb muscle electrical signals

Interference on baseline: ensure no mains cables are crossing the ECG wires. If you still have a problem, try and run the ECG machine on its battery rather than on the mains. Still got a problem? Move the ECG machine to the other side of the bed and unplug any non-essential electrical equipment around the bed

Odd axis on ECG: make sure that you have the leads attached to the correct electrodes, especially the limb leads

If all else fails, get another machine.

[back to top]