T2 Cardiac Dysrhythmias Flashcards
The ability of the body to deliver nutrients and oxygen via the blood through arteries and capillaries, organs
and in turn picking up cellular waste and carbon dioxide from the cells via the veins
Cardiac dysrhythmias decrease perfusion and can lead to organ failure
Perfusion
Gas exchange vs perfusion?
Cardiac arrythmias can decrease?
Perfusion- how the blood gets there or is able to carry to end point
Has exchange- exchanging of oxygen and carbon dioxide across capillary and aveolli
Perfusion
Perfusion assessment
Recognize indicators of adequate and inadequate perfusion*
Central perfusion: assess HR and BP
Cerebral tissue: patients mental status
Peripheral tissue: extremity temp, color, pulse, cap refill
Low bp and confusion, fever, bounding, threads pulse capillary refill more than 3seconds= perfusion issue
Central= organs , heart
How does heart rhythm affect perfusion ?
Body receives more blood oxygen demand with a faster/more beats
Pacemaker of heart
SA node (top left)
Cardiac conduction system
SA node (right atrium) travels to AV node in middle - travels down bundle of His, bundle branch , fibers which causes ventricular contraction This shows QRS complex
SA node stimulates P wave -> QRS -> T wave
AV node stimulates PR segment
The length of time it takes for electricity to come back to normal, repoloarize and be able to receive electrical stimulation again.
Electrical impulses 60 to 100 beats/min
P wave on ECG
Alterations in HR occur here first*
If something wrong see what?
How it connects to EKG waveforms?
Sinoatrial node *
Elevated or decreased heart rate or dysrhythmias
Affected by sympathetic and parasympathetic nerves that increase or decrease the heart rate
Atrial depolarization(contraction) and P wave on ECG
beats 40-60 beats/min
Contraction known as “atrial kick”
If SA node stopped working - AV works as back up but only 40-60 bpm so may need assistance (pacemaker) or may have decreased perfusion
How it connects to EKG waveforms?
Atrioventricular Node -AV node
Below right atrium
PR segment and contraction through AV node and bundle of His which allows atrium to contract and ventricles to fill before ventricular contraction
Atrial kick contributes to additional blood volume for greater cardiac output
Right bundle branch system
Left bundle branch system
(beats 20-40 beats/min)
Causes ventricles to contract
Not enough on its own to give proper perfusion
How it connects to EKG waveforms?
Bundle of His
Stimulates ventricles
Ventricular depolarization = QRS on ECG
Conduction begins in SA node, located in right atrium
SA node is pacemaker of the heart, effected by sympathetic and parasympathetic nerves which increase or decrease heart rate
Impulses travel through SA node resulting in atrial depolarization (contraction) and p wave on ECG
AV node beneath right atrium, impulse slows through AV node before proceeding to ventricles
AV junction is PR segment and includes conduction through AV node and Bundle of His, allows atrium to contract and ventricles to fill before ventricular contraction
Atrial kick contributes additional blood volume for greater cardiac output
Bundle of His= right and left bundle to stimulate ventricles
End of bundle branches are purkinje fibers.
Ventricular depolarization = QRS on ECG
Yes
Within the cardiac condition system there are Specialized myocardial cells
Characteristics of the cells include:
Automaticity: able to spontaneously generate an electrical impulse
Excitability: capable of being activated and reacting to electrical stimuli
Conductivity: able to conduct electricity
Contractility: form a contraction and strength of the hearts contraction during systole
ECG waveforms are measured in what??
Isoelectric, positive deflection and negative deflection
One small block =_____? seconds.
Five small blocks equal one large block=____seconds
Five large blocks =1 second and 30 large blocks =6 seconds
Left to right- measure time
Top to bottom- measures voltage and amplitude (how much voltage is conducted)
Measure how long each waveform should be
amplitude (voltage) and duration (time).
One small block = 0.04 seconds.
Big-0.2 seconds
Each segment between the dark lines (above the monitor strip) represents 3 seconds (15 large boxes). To estimate the ventricular rate, count the QRS complexes in a 6-second strip and then multiply that number by 10 to estimate the rate for 1 minute. In this example, there are 9 QRS complexes in 6 seconds. Therefore the heart rate can be estimated to be 90 beats/min.
Look at rate - count qrs x by 10 (6 seconds is 15 boxes)
There are 9 QRS x 10= 90 bpm
_____wave is usually positive deflection that represents atrial depolarization. Every beat has a this wave hopefully. First thing will see.
P wave
____segment/interval is isoelectric line from end of P wave to QRS represents time traveled between SA and AV node .12-.20 or 3-5 little squares.
PR segment
____complex represents ventricular depolarization .04-.12 seconds
QRS complex
______ is first negative deflection after p wave and isn’t always present (can mean myocardial necrosis)
Q wave
______duration is time it takes impulse to travel through Bundles and cause contraction
QRS
_____ represents early ventricular repolarization (becoming ready to be stimulated again) isoelectric line
ST segment
______follows ST segment and represents full ventricular repolarization, usually positive and rounded but can be tall, peaked, inverted, or flat
T wave
_____ is not normally seen and may represent electrolyte abnormality (hypokalemia)
U wave
____interval varies with age, gender, and heart rate.
QT
How to analyze an ECG?
Should be what?
Determine heart rate Determine heart rhythm Analyze P waves Measure PR interval Measure QRS duration Examine ST segment Assess T wave and QT interval Interpret rhythm
**Should be systematic and consistent
Rate=speed
Rhythm=consistency
P wave= are p waves present, are p waves consistent (PR interval)
Simplified rhythm analysis ?
4 steps
Determine heart rate-bmp
Determine heart rhythm- is the hr even and rhythmic/regular
Assess P wave
Present and consistent- one for each QRS and they look the same
Interpret rhythm- use above info to interpret this