ECG Flashcards
Automaticity
Is the ability to initiate an impulse spontaneously and continuously
Excitability
Is the ability to be electronically stimulated - electrically charging cells
Conductivity
Is the ability to transmit an impulse along a membrane in an orderly manner
Conduction system
Begins in the SA ( making the atria contract) , spreads to the atrium to the AV node ( AV contracts and blood is contracted out)
Goes to left and right bundle branch ( purkinje fibres)
Contractility is known as the
Switch in the house that mechanically turns things on
SA rate
60-100
AV rate
Fires at a rate of 40-60
purkinje fibres rate
20 - 40
SA , AV and purkinje fibers are know as the
Pace makers of the heart
What makes my AV node override SA fire
It can fire itself so if it fills full it will fire up which causes dysrhythmias
Stimulation of the vagus nerve causes
A decreased rate of firing of the SA node and slowed impulse conduction of the AV node ( parasympathetic nervous system)
Stimulation of the sympathetic nerves In the heart
Increases SA node firing , AV node impulse conduction and cardiac contractility
( sympathetic system)
What does the sympathetic system effect?
Pupils expand
Fast and shallow breaths
Heart pumps faster
Gut inactive
Parasympathetic system- how does this effect the body?
Pupils shrink
Slow deep breaths
Heart slows
Gut active
Central monitoring
Sent to a central place for them to look at and call back like telemetry
Bed side monitoring
Monitor at the bed side so we know as soon as possible when something happens
Telemetry monitoring
The observation of a patients HR and rhythm at a site distant from the patient
How many leads in electrocardiographic monitoring
5 leads
What should we avoid when putting on leads for electrocardiographic monitoring
Avoid bony prominences
P wave
SA sending out the impulse and causing the contraction of the atrium
QRS
Contraction( also known as DEPOLARIZATION) of the ventricles
T wave
Resting spot where the heart fills
U wave
Similar to the T wave but not seen often
When we are assessing the cardiac rhythm
Is the patient hemodynamically stable
What are we looking at when it comes to seeing if a patient is hemodynamically stable
BP, HR, SA, O2 monitor, cap refill,
Why should we not treat the monitor and not the patient
It may be normal for them
Best places to take pulse
Carotid & femoral ( only unconscious)
Normal sinus rhythm
60-100 bpm
Starts in the SA node
Causes of bradycardia
Medications , high activity level, hypothyroidism, , hypoglycemia, increased intracranial pressure, inferior myocardial infarction ( MI). Anaerobic athlete
1 med that causes bradycardia
Betablocker