Chapter 2: Artifacts Flashcards
A normal ECG consists of components which indicate?
Electrical events during one heartbeat.
The waveform are labeled as?
P, Q, R, S, T and U.
What does the P wave, QRS complex and T waves recorded during the ECG represent?
Depolarization (contraction) and redepolarization (recovery) of the myocardial cells.
The unusual and unwanted activity in the recording is caused by electrical activity of the heart?
No.
The interferences in the ECG tracing are known as?
Artifacts.
It’s common for ECG to have some form of artifact, but it’s important to?
Reduce any interference as much as possible to ensure an accurate ECG.
Does newer ECG machines can automatically filter out artifacts?
Yes.
What are three common artifacts?
Muscle tremor, electrical interference and movement of the electrodes.
Muscle Tremor is a result in?
Voluntary or involuntary muscle movement.
When does voluntary movement can occur?
When the patient moves or talks.
When does involuntary movement can occur?
In certain diseases (Parkinson’s) or when the patient shivers or sneezes.
What is another disturbance emanating directly from the surrounding environment?
Electrical Interference.
The ECG machine is designed to pick up?
Electrical activity within the heart and electrical activity from nearby equipment or wires.
When does movement of the electrodes can occur?
When the weight of the lead wires pulls the electrodes away from the skin and contact is lost.
Does the electrodes can move or come loose if the person leans, rolls over, or otherwise fiddles with the electrodes?
Yes.
