Test Two: Cardiac Dysrhythmias Flashcards
What is a dysrhythmia?
Abnormal cardiac rhythm
- Disorder of the formation or conduction of the electrical impulses in the heart
What are the three disturbances of dysrhythmias?
- rate
- rhythm
- both
What is used to diagnoses dysthymia’s?
ECG
What is the P wave in the conduction system of the heart?
depolarization of the atria
What is the Q, R, S wave in the conduction system of the heart?
depolarization of the ventricles
What is the T wave in the conduction system of the heart?
repolarization of the ventricles
What is the U wave in the conduction system of the heart?
may represent repolarization of the Purkinje fibres
What are five ways to evaluate dysrhythmias?
- Holter monitoring
- Event recorder monitoring
- Exercise treadmill testing
- Signal-averaged ECG
- Electrophysiological study (invasive)
What is ECG monitoring?
Graphic tracing of electrical impulses produced by the heart
What are some pt preparation that needs to be done before ECGs?
- clip excessive hair on chest wall
- rub skin with dry gauze
- may need to use alcohol for oily skin
- apply electrical conductor gel
What is telemetry monitoring?
a non-invasive, portable way to observe the HR and rhythm at a distant site
type types:
–> centralized monitoring system
–> sophisticated alarm system alerts when it detects dysrhythmias, schema, or infarction
What is a normal sinus rhythm?
- sinus node fires 60-100bpm
- follows normal conduction pattern
- Rhythm= regular and R-R constant
What is sinus bradycardia?
- sinus nodes fires <60bpm
- rhythm= regular and R-R constant
this is considered normal in aerobically trained athletes and during sleep
What are symptoms of sinus bradycardia?
-hypotension, pale, cool skin, weakness, angina, dizziness, confusion, SOB
What is the treatment of sinus bradycardia?
- atropine
- pacemaker if needed
What are causes of sinus bradycardia?
- beta-blockers
- CCB
- athletes
- hypothermia
- hypothyroidism
- vagal stimulation
What is sinus tachycardia?
- rate = >100bpm
- rhythm = regular and R-R constant
What are symptoms of sinus tachycardia?
dizziness and hypotension (due to decreased co), angina, palpations, alterations in bp, dizziness, SOB, diaphoresis
What are causes of sinus tachycardia?
exercise, pain, hypovolemia, anemia, myocardial ischemia, heart failure, fever, shock, hypoxia, stress, medications, caffeine
What is the treatment for sinus tachycardia?
- determine underlying cause and correct it!!
- oxygen, fluids
- medications
–> analgesics, antipyretics, B-adrenergic blockers
What is premature atrial contraction?
- extra heartbeats that begin in one of your heart’s two upper chambers (atria)
- may be stopped, delayed, conducted normally at the AV node
** may be an ideation of a more serious dysrhythmia in heart disease**
What is the causes of premature atrial contraction?
low potassium
- emotional stress, caffeine, tobacco, alcohol, hypoxia, COPD, valvular disease
What is the treatment of premature atrial contraction?
- individualized, depends on cause
- B-adrenergic blockers
What is a atrial flutter?
-known as ‘saw tooth’ or ‘picket fence’ shaped flutter waves
- rhythm = regular/irregular
- upper chambers (atria) to pump very rapidly
-arrhythmias
What is the causes of atrial flutter?
CAD, HTN, mitral valve disorders, pulmonary embolus, chronic lung disease, cardiomyopathy, hyperthyroidism
drugs
- dioxin, quinidine, epinephrine
What is the symptoms of an atrial flutter?
decreased BP and syncope
What is the treatment of an atrial flutter?
- radiofrequency catheter ablation
- vagal stimulation
- medications: warfarin, antidysrhythmia drugs
What is an atrial fibrillation?
linked to brain tumours
- total disorganization of atrial electrical activity due to multiple ectopic foci, resulting in loss of effective atrial conduction
- irregular and often very rapid heart rhythm (arrhythmia)
- rate = atrial > 400-600
- rhythm = irregularly irregular. wiggly
MOST COMMON
What is the causes of atrial fibrillation?
CAD, HF, MI, HTN,
rheumatic heart disease
What is the S&S of atrial fibrillation?
- Pulse deficit with rates > 90
- ↓BP
- Syncope
What is the treatment of atrial fibrillation?
- Decrease ventricular rate
- Prevent embolic stroke
- Drugs for rate control: digoxin, β-adrenergic blockers, calcium channel blockers
- Long-term anticoagulation: Coumadin
What is premature ventricular contractions?
Premature occurrence of a wide and distorted QRS complex. rate depends upon underlying rhythm.
- extra heartbeats that begin in one of the heart’s two lower pumping chambers (ventricles)
What is the cause of premature ventricular contractions?
- Stimulants: caffeine, alcohol, nicotine, aminophylline, epinephrine, isoproterenol
- Digoxin
- Electrolyte imbalances
- Hypoxia
- Fever
- Disease states: MI, mitral va
what is the S&S of premature ventricular contractions?
Palpitations
What is the treatment of premature ventricular contractions?
- Medication
- Treatment of underlying cause
- Oxygen therapy for hypoxia
- Electrolyte replacement
What is ventricular tachycardia?
- Run of three or more PVCs
- Rate = atrial rate not determined
- Rhythm = Regular but can be slightly irregular
- Considered life-threatening because of decreased CO and the possibility of deterioration to ventricular fibrillation
- lower chamber of the heart beats too fast to pump well and the body doesn’t receive enough oxygenated blood.
What is the cause of ventricular tachycardia?
MI, CAD, Electrolyte imbalances, Cardiomyopathy, Heart Failure
What is the symptoms of ventricular tachycardia?
↓BP, Absent Pulse, Confusion, Syncope
What is the treatment of ventricular tachycardia?
Assess the patient, Medication
Code Blue!!!! 5555
What is ventricular fibrillation?
- Severe derangement of the heart rhythm characterized on ECG by irregular undulations of varying contour and amplitude
- No effective contraction or CO occurs
- Unresponsive, pulseless, and apneic state
- If not treated rapidly, death will result
What is the treatment of ventricular fibrillation?
Immediate initiation of CPR and advanced cardiac life support (ACLS) measures with the use of defibrillation and definitive drug therapy
What is the cause of ventricular fibrillation?
- Accidental electric shock
- Hyperkalemia
- Hypoxia
- Acidosis
- Drug toxicity
What is asystole?
- Represents total absence of ventricular electrical activity
- No ventricular contraction (CO) occurs because depolarization does not occur
- Almost flatlining
What is the five H’s and T’s of systole
- Hypoxia, Hypothermia, Hypokalemia, Hypovolemia, Hydrogen ion (acidosis)
- toxins (drug overdoses), Tamponade (cardiac), Tension pneumothorax, Thrombosis –heart (AMI), Thrombosis- lungs (pulmonary embolus)
What is the symptom of asystole?
Loss LOC, Pulselessness, Respiratory arrest, PATIENT IS DEAD!
What is the treatment of asystole?
- Assess the patient, Confirm the absence of pulse
DNR Order??, Perform immediate CPR!, Code Blue 5555 (CKHA), Confirm the rhythm in TWO leads. - Explore possible cause and treat it = ASAP
What is defibrillation?
Most effective method of terminating VF and pulseless VT
- unsynchronized
What is synchronized cardio version?
Choice of therapy for hemodynamically unstable ventricular or supraventricular tachydysrhythmias
What is implantable cardioverter-defibrillator(ICD)?
A device that detects and terminates life-threatening episodes of tachycardia or fibrillation
What is a pacemaker?
- An electronic device that provides electrical stimuli to the heart muscle
- Used for slower-than-normal impulse formation, to control some tachycardias, or for advanced heart failure
- May be permanent or temporary
What is the complications of pacemakers?
- Infection
- Bleeding or hematoma formation
- Dislocation of the lead
- Skeletal muscle or phrenic nerve stimulation
- Cardiac tamponade
- Pacemaker malfunction