Dysrhythmias Flashcards
Length of time for PR interval
0.12-0.2s
Length of time for QRS
<0.12
What two conditions is sinus bradycardia normal?
Athletes
During sleep
Causes of Sinus Brady
Meds: Beta blocker, digoxin Valsava Maneuver Carotid massage Hypothyroid Hypothermia
Symptomatic Sinus Brady
Hypotension Diaphoresis Chest pain SOB Change in mental status, fatigue Decrease C.O. Decrease O2 Cool skin
Treatment for Sinus Brady
Do not treat if normal for pt
- Treat underlying cause
- Give O2
- Pacer
- Epinephrine or dopamine gtt
- Atropine helps increase HR (inhibits vagus nerve)
Sinus Tachycardia
100-149bpm
Causes of Sinus Tachy
Running or exercise Hypovolemia (dehydration) Pain, Anxiety Fever, Infection CHF (heart thinks its not getting enough O2 out) Hyperthyroid
Symptoms of Sinus Tachy
Depends on the patients tolerance to the increased HR
May experience dizziness, hypotension, or increase need for CO2
Treatment for Sinus Tachy
If normal, no treatment
- Treat underlying cause (hydrate pt, treat fever)
- Limit stimulants:
- Give O2
- Give lasix if HF
- Carotid massage (physician only)
- Valsalva maneuvers (bear down) - Meds: CCB, Beta blocker
Premature Atrial Contraction (PAC)
Contraction originating from ectopic focus in atrium on location other than the sinus node
Travels across atria by abnormal pathway, creating distorted P wave
Is stopped, delayed, or conducted normally at the AV node
PAC causes
Emotional stress Caffeine, tobacco, or alcohol Infection, inflammation COPD Valvular disease
PAC treatment
- Depends on symptoms
- Adrenergic blockers may be used to decrease PACs (caution in COPD & asthma pt’s)
- Usually Mg replacement ordered
Atrial flutter
- Recurring, regular, sawtooth-shaped flutter waves
- Associated with slower ventricular response
Atrial flutter causes
CAD, MI, HTN Valve problems Rheumatic heart disease HF Hyperthyroid Possible post-CABG Lone Afib Holiday heart Hyperthyroid Mitral valve disease Heart diseases
Atrial flutter Symptoms
Decreased C.O. Palpitations SOB, chest pain Fatigue, syncope HF Change in mental status
Atrial flutter treatment
- Heparin drip: to prevent clots
- Meds: digoxin, CCB, Amiodarone (last line)
- Cardioversion
- Coumadin: long term, monitor PT/INR
- Ablation
- Pacemaker
Paroxysmal Supraventricular Tachycardia (PSVT)
HR greater than 150 bpm
Usually, no P wave identifiable
Causes of PSVT
Overexertion Emotional stress Stimulants Digitalis toxicity CAD