T5: ECG Flashcards
What does an electrocardiograph do?
- Monitors heart rate, cardiac rhythym and axis deviation.
- Records electrical activity of the heart.
What does a normal heart contraction require?
Normal electrical conduction of activating electrical impulses through cardiac muscle tissue.
What are ECGs taken for?
- Diagnosing cardiac diseases and abnormal cardiac rhythym (arrythmia)
- Aids in detection of enlaged heart
- Aids in detection of electrolyte, systemic or metabolic disorders
- Anaesthetic monitoring
- Useful in cardiac arrest cases and CPR
- Useful in diagnosing ventricular fibrillation
Where in the heart does deoxygenated blood enter and where does it go?
Right side of heart.
Pumped to lungs.
Where in the heart does oxygenated blood enter and where does it go?
Comes from the lungs and enters left side of heart.
Pumped to the body.
What is a trace?
The recorded electroactivity on heat sensitive paper
What does an ECG represent?
Amplitude and duration of electical activity
What happens in each heart contraction?
Each contraction of the heartis preceded by an electrical wave font that stimulates the heart to contract and relax in preperation for next heart beat.
What is Depolarization?
Contraction of the myocardium
What is Repolarization?
Relaxation of cells after depolarization
What is systole?
Contraction of the ventricals
What is diastole?
The filling of ventricles (relax)
What are the parts to an ECG?
- P Wave
- QRS Interval
- ST/T wave
- PR interval
- QRS Duration
- QT Interval
- RR Interval
- PP interval
Attempt to draw a typical ECG printout.
What does each ECG lead have?
Each lead has a positive and negative pole which is attached to the skin of the animal and can be used to measure the spread of the eclectrical activity within the heart.
Different leads allow you to look at the heart from different angles. Each angle is called a lead.
Describe Alligator Clips
- Good for once off ECGs
- Clips should be placed on loose folds of skin at the elbows and knees.
- Requires a conducting medium (eg spirit) just sufficient enough to wet clip and hair through skin.