Abnormal Rhythms: Review
1.
Sinus Bradycardia:
Less than 60 beats per minute
P waves are present (coming from the SA node)
P-R ratio is 1:1
PR interval is normal within (0.12-0.20)
QRS complex is normal within (0.40-0.10)
The patient with Sinus Bradycardia might feel…….
SOB
Confusion because the brain is not getting enough O2
Causes of Sinus Bradycardia:
Hypothermia
Increased vagal tone (someone who is baring down)
Hypothyroidism
IICP – whenever someone has IICP it causes the BP to decrease and the HR to decrease
SOME PATIENTS MIGHT NOT BE SYMPTOMATIC
TREATMENTS for sinus Bradycardia
:
If there are Asymptomatic and hemodynamically stable
there is NO TREATMENT
Symptomatic Bradycardia…….
Atropine
Temporary pacing
Dopamine/ norepinephrine infusion
Atropine will not work on someone with a heart transplant
2.
Sinus Tachycardia
Greater than 100 beats per minute
P waves are present, it is still coming from the SA node
P-R interval is still 1:1
PR interval is normal (0.12-0.20)
QRS complex is normal (0.4-0.10)
Causes of Sinus Tachycardia:
Exertion
Anxiety
Fever
Anemia
Hyperthyroidism
Pain
Drugs
Treatment for Sinus Tachycardia:
We need to determine the underlying causes first ex. If the patient has anemia
Beta-adrengeric blockers to reduce heart rate and O2 use
3.
Supraventricular Tachycardia/ Narrow complex tachycardia
Arrhythmia that is occurring in the atria
Rhythm is still regular
Ventricular response is greater than 150/min
There are NO P WAVES meaning that this impulse is NOT coming from the SA node
Since there are no P waves there is NO PR interval
QRS complex is still normal (0.40-0.10)
The QRS complex becomes noticeably narrower
Causes of Supraventricular tachycardia/ narrow complex tachycardia:
Unknown etiology
Emotional stress
Excessive alcohol, caffeine, or tobacco
Valvular disease
CAD
Digitalis toxicity
Treatment:
If the person is hemodynamically stable …..
We attempt the Vagal maneuveur
Adenosine
If after 3 doses of adenosine, the rhythm continues and the patient is stable, the MD might
order a calcium channel blocker or a beta-blocker
Adenosine is going to temporarily stop their heart rate for about 6 seconds, we do this to
attempt to have the SA node kick in
If the person is hemodynamically unstable……
We do synchronized cardioversion
If the patient is diaphoretic and their resp rate is very high it means that we need to reassess
our patients vitals because they might be no longer stable
Synchronized cardioversion, we put the pads on the patient and we try to get the impulse on
the R waves NOT the T waves.
