common dysrhythmias Flashcards
what is any heart rhythm that originates from the SA node?
sinus rhythm
normal lub dub
PR interval: 0.12 - 0.20
QRS: less than or equal to 0.12 seconds
Rate: 60-100 bpm
palpable pulse and BP
normal sinus rhythm
Normal intervals but it irregularly marches out
irregular rhythm
sinus arrhythmia
Heart rate: usually between 60-100 bpm
Rhythm: irregular
P waves: identical, seen before each QRS
PR Interval: 0.12 - 0.20 seconds
QRS: less than 0.12 seconds
heart rate increases slightly with inspiration, decreases slightly with expiration
rhythm is irregular, varies with respiration patteren
Sinus Arrhythmia
variant of normal sinus rhythm
normal in:
- young children
- athletes
Rate: les than 6o
Rhythm: regular
P wave: identical, seen before every QRS
PR Interval: 0.12 - 0.20
QRS: less than or equal to 0.12
- (R-R, P-P) march equally
Sinus Bradycardia
can be normal for some people
A patient is experiencing bradycardia, could be on what class of medications?
beta blockers
calcium channel blockers
digoxin
sometimes in sinus bradycardia you will see a prolongation of the QT wave, what should the nurse do?
asses the patient then notify the HCP
The prolongation can interfer with the new heart beat/ next p wave and therefore cause different dysrhythmias
causes of sinus bradycardia
being an athlete;
sleep –> relaxation;
excessive vagal tone when acetylcholine* is released by PSNS and can slow down the SA Node from firing; medications such as beta blockers, calcium channel blockers, and digoxin are negative chronotropes for HF and can slow down HR from firing; low oxegenation (hypoxia) is a late sign, inferior wall MI as the lower part of the heart causes problems of the SA Node firing
*plays a vital role in the central and peripheral nervous system.
watch for digtoxicity
How will a nurse treat Sinus Bradycardia?
- if the patient is hemodynamically stable, nothing
- if the patient is hemdynamically UNstable, …
- asses the patient, BP, Cap Refill, Urinary Output
- ## treat an underlying cause, check medications
digon toxicity
may need anticholenergics (ATROPIN) if to much vagal tone
atropine has a short half life and the effectiveness wears off, if this is continous the patient may need a pacmaker to keep it beating
hypoxic, give medications
avoid straining when consitpated bc it can contribute to too much vagal stimulation
Rate: 101 - 160 (Adults)
Rhythm: regular
P wave: identical, seen before every QRS, may be buried in preceding T wave
PR interval: 0.12 - 0.20
QRS: less than or equal to 0.12
Sinus Tachycardia
Increased metabolic demands that can cause sinus tachycardia
-fever, pain, anxiety, exercise
this may be a normal compensatory rxn
What medications can cause Sinus Tachycardia
-catecholamines
- anticholinergics
- caffine
- nicotine
- albuterol
- thyroid hormone
sinus tachycardia treatment
fever –> acetaminophen;
pain –> pain medication;
axiety –> antiaxiety, teach breathing techniques;
simulents – remove them;
hypovolemia bc of fluid loss –> give fluids;
hypovolemia bc of blood loss –> give blood;
infection –> give antibiotics;
hypoglycemic –> food/sugar/carbs;
Increased HR –> BB and CCB to decrease HR
Ablation
can be a normal compensatory mechanism but need to treat underlying cause
hypovolemin, low BP with high HR
Ventricular and atrial rates are the same in sinus rhythm.
A. True
B. False
A. True
- impulse originates outside of sinus node (from atrial tissue or AV node)
- narrow complex QRS less than or equal to 0.12
P wave and T waves collide and the R’s still march out
Atrial Dysrhythmias
Atrial (narrow) dysrhythmias
aka* supraventricular tachycardia*
The P wave and the T wave become one because the heart is beating so fast
firing above in the SA Node
What can the nurse do to slow down an SVT?
- have the patient practice the valsalva manuver
- get the patient to cough, bear down
- give adenosine to reboot the heart, IVP FAST
- do a carotid sinus massage
- ## accessory pathway
adenosine will show asystoly and then hopefully they will get a normar rhythm after
premature “P” wave shaped differently than P wave coming from SA node
Premature Atrial Contractions (PAC)
- abnormal shaped P waves (shaped differently)
- Early timing (premature)
R’s march out but the P waves looks different
what are treatments for premature atrial contractions?
- non usually needed
- treat underlying causes: reduce stress, substances
- administer potassium and magnesium
what are some causes of premature atrial contractions?
Think nursing students showing premature atrial contractions
- stress, fatigue, anxiety, excitement
- stimulants: caffine, tobacco
- medications: sympathomimetic (catecholamines), amphetamines
- electrolyte imbalances: hypokalemia, hypomagnesemia
ADHD drugs
- rapid, recurring atrial focus
- reentrant circuit, right atrium
- sawtooth “picket fence” appearance of flutter waves
Atrial Flutter
problematic bc the atria does NOT contract to push the blood into the ventricles, blood pools and causes clots
When the nurse sees atrial flutter, what should she do?
- asses cardiac output bc they lost their atrial kick (15-20% decrease in cardiac output)
- rate less than 100 = controlled ventricular response = good
- ## rate greater than 100 = rapid uncontrolled ventricular response = concerned bc ventricles are firing quicker and will show clinical manefeststions such as: palpatations, weakness, fatigue, SOB, nervousness, anxiety, syncope, chest pain, heart failure, shock
goal: contril ventricular response and ensuring it is less than 100
concern: it can get rater and rapid (300)
looks like a lot of p waves
count the waves to r ratio
how will the nurse treat atrial flutter?
give digoxin, beta blockers, diltiazem, amiodarone
worry about clots
- Most common dysrhythmia
- No P waves, wavy baseline instead, irregularly irregular narrow rhythm
- Continuous, rapid, disorganized, chaotic discharges from multiple atrial foci
- Atria quiver, loss of atrial kick (decreases CO), mostly concerned about blood clots
- increased Risk of stroke, embolism
Atrial fibrillation
wavy p waves , think fine to fib, fine line
What are causes of atrial fib?
- age
- HTN
- CAD
- VAlvular DZ
- COPD
- Heart surgery
- congenital heart dz
- Hyperthyroidism
most blood clots form in the** left atrial appendage **and once it gets to the left ventricle and contracts it can lead to clots in the blood
