Care of pats with dysrhythmias Flashcards
atrial depolarization; contraction atria; first wave
P
total time for atrial to depolarize and time takes for impulse to travel from SA node through Purkinje fibers
PR interval -
big one; ventricular depolarization/contraction
QRS complex -
early ventricular repolarization
ST segment -
ventricular repolarization - back to resting state
T wave -
total time for depolarization and repolarization
QT -
Determine heart rate - in a 6 sec strip count number QRS complexes and x10
Determine heart rhythm – can be regular or irregular; same difference between R’s; use calibers and see if difference between Rs sim
Analyze P waves
Small square = .04; large .2
Measure PR interval (normal .12-.20)
Measure QRS duration (normal .06-.12)
Examine the ST segment
Interpret rhythm and differentiate normal and abnormal cardiac rhythms
ECG rhythm analysis
Are P waves present?
Are the P waves occurring regularly?
Is there one P wave for each QRS complex? Regularly - space in between each
Are the P waves smooth, rounded, and upright in appearance, or are they inverted?
Do all the P waves look similar?
Analyze P waves
Are PR intervals greater than 0.20 second?
Are PR intervals less than 0.12 second?
Are PR intervals constant across the strip?
Measure from the beginning of the P wave to the beginning of the QRS
Measure PR interval (normal .12-.20)
Are QRS intervals less than or greater than 0.12 second?
Are the QRS complexes similar in appearance across the ECG paper?
Measure from the beginning of the QRS to end of S wave
Measure QRS duration (normal .06-.12)
Elevation may indicate myocardial infarction, pericarditis, hyperkalemia
Depression is associated with hypokalemia, myocardial infarction, ventricular hypertrophy
Examine the ST segment
Normal strip
Rate: 60-100 beats/minute
Rhythm: atrial and ventricular rhythms are regular - measure from each P and R wave are equal and consistent
P waves: Present, consistent configuration, one P wave before each QRS complex
PR interval : 0.12-0.20 second and constant; within norm range
QRS duration: 0.06-0.12 second and constant; within norm range
R to R constant; P to P constant
No interventions required
Normal sinus rhythm (NSR)
Variant of NSR
Type sinus rhythm; some irregularity
Results from changes in intrathoracic pressure during breathing
Has all the characteristics of NSR except for its irregularity
The PP and RR intervals vary, with the difference between the shortest and the longest intervals being greater than 0.12 second (three small blocks)
Rate: Atrial and ventricular rates between 60 and 100 beats/minute; norm rate
Rhythm: Atrial and ventricular rhythms irregular, with the shortest PP or RR interval varying at least 0.12 second from the longest PP or RR interval
P waves: One P wave before each QRS complex; consistent configuration
PR interval: Normal, constant
QRS duration: Normal, constant
No interventions required.
Sinus arrhythmia (SA)
Any disorder of the heartbeat/electrical activity
Tachydysrhythmias – heart rates greater than 100 beats per minute; fast
Bradydysrhythmias – heart rates less than 60 beats per minute; slow
Premature complexes – early rhythm complexes; if they become more frequent, especially those that are ventricular, the patient may experience symptoms of decreased cardiac output; ectopy: early complex; early ventricular/atrial contraction - ventricular more serious and more frequent more serious
Repetitive rhythm complexes
Etiology – may occur for many reasons; MI, electrolyte imbalance - K/Mg; hypoxic, low blood volume, hypovolemia, caffeine, nicotine, stress
Can be classified by their site of origin in the heart (sinus, atrial, ventricular)
Managed with antidysrhythmic drug therapy depending on dysrhythmia
Dysrhythmias
Bigeminy
Trigeminy
Quadrigeminy
Repetitive rhythm complexes