Wk 2 Dysrhythmias Flashcards
How long should the PR interval be?
0.12-0.20 seconds
How long should the QT interval be?
Under 0.38 seconds
How long should the QRS interval be?
0.10 seconds or less
If there is a delay between the atria and the ventricles, what will happen on the EKG/tele strip?
the PR interval will be longer
What is a potential cause of a peaked T wave?
Potassium imbalances
How many seconds does 1 small box on an EKG represent?
0.04 seconds
How many seconds does 1 big box on an EKG represent?
0.20 seconds
How many small boxes make up one big box on an EKG?
5
How many seconds does 1 EKG represent?
6
What do the bars on the top of the graph mean on an EKG?
In between each bar is 3 seconds
An ST elevation needs to be in __ continuous leads to diagnose a STEMI
2
What is an artifact?
Irregularity that is not due to the electrical conduction of the patient’s heart, such as disconnection, patient is receiving PT, etc.
What are 3 classifications of dysrhythmias?
Premature, Brady, tachy
What is a bradydysrhythmia?
HR less than 60
When are coronary arteries perfused?
During diastole
What is a common reason beta blockers are given?
To slow the heart rate so myocardial oxygen demand is reduced
What are two benefits of bradycardia?
decreased myocardial oxygen demand
Increased coronary artery perfusion time
What is a consequence of bradycardia and the coronary arteries?
If the heart rate is too slow the coronary arteries won’t perfuse and angina will occur
If a patient is bradycardic and also has inadequate blood pressure, this may cause what 4 complications?
Myocardial ischemia/infarct
Dysrhythmias
Hypotension
Heart failure
What is considered tachycardia?
HR above 100
What happens to the coronary arteries during tachycardia?
Shortens diastolic time which shortens coronary perfusion time
What is an initial benefit of tachycardia?
Increased cardiac output and BP
What happens if tachycardia is sustained?
Decreased ventricular filling and decreased CO &BP
BP is an indirect measure of __ __
cardiac output
How does tachycardia increase the workload on the heart?
Increases myocardial oxygen demand
What causes angina?
Lack of/decreased coronary perfusion
What neurologic symptoms might someone have with tachycardia or Brady cardia?
Restlessness Anxiety Confusion Dizziness Syncope
What is pulse deficit?
When 2 nurses take apical and radial pulses and there is a deficit (should get the same number)
Pulse deficit is an indication of poor __ __
peripheral perfusion
Pulmonary crackles are an indication of __-sided heart failure
left
What is orthopnea?
SOA when lying down
JVD is an indication of __-sided heart failure
right
Why does Brady/tachycardia lead to decreased urine output?
Perfusion to kidneys suffers and they stop making urine
