2.2 Cardiovascular, Cardiac Monitoring Flashcards
Identify and explain the significance of the P wave
Usually upright and uniform
Followed by a QRS complex
Represents atrial depolarization
Identify, measure and explain the significance of the QRS complex
Measured from the start of the Q to the end of S wave
Represents time from Bundle of His impulse through the ventricles
Varies in shape
Not all patients have a Q or S
Normal: <0.12 seconds
Identify and explain the significance of the T wave
Normally upright and uniform
Rounded and smooth
Inverted T waves may indicate myocardial ischemia
Peaked T waves may indicate hyperkalemia or myocardial injury
Represents ventricular repolarization
No associated muscle activity
How do you measure PR interval? Represents? What is the ranges?
PR Interval
Measure from beginning of P wave to beginning of QRS complex
Represents time from SA Node impulse through the AV Node and Bundle of His
Normal: 0.12-0.20 seconds
Describe parameters and identify regular sinus rhythm
R-R intervals are constant
P-P intervals are constant
Rate is 60-100 (counting the R wave in a 6 sec strip)
P waves are uniform with 1 P wave to 1 QRS complex
PR interval is between 0.12-0.20 seconds
QRS complex is <0.12 seconds
Describe nursing care for patient on telemetry
Verify order
Explain procedure and why monitoring is needed
Explain patient responsibilities
Prepare skin: alcohol wipe, shave skin if necessary
Correct lead placement
Connect to monitor
Set alarms specific to the patient
What teaching should the RN to patient and family on telemetry?
Keep leads on at all times No showering Do not adjust monitoring system Call if lead falls off Call if chest pain or change in heart rhythm
Identify and explain significance of Ventricular tachycardia dysrhythmias?
Ventricular tachycardia LIFE THREATENING! Regularity: usually regular (saw tooth) Rate: ventricular rate 150-250 beats P waves: none PR interval: none QRS complex: wide, >0.12 seconds but uniform
Most often caused by coronary artery disease, MI, cardiomyopathy, valve disease, cardiac surgery
May be pulseless or may be perfusing and even stable
Assess patient
Treat with antiarrhythmic meds if stable
Cardioversion if unstable
Identify and explain significance of Ventricular fibrillation dysrhythmias?
Ventricular fibrillation LIFE THREATENING! Regularity: chaotic baseline Rate: no identifiable waves to measure P waves: non identifiable PR interval: none QRS complex: none CODE BLUE, can not produce a pulse GOAL IS DEFIBRILLATION
identify and explain significance of Ventricular standstill (asystole) dysrhythmias?
No electrical activity Complete arrest No P, PR interval, QRS CODE BLUE IMMEDIATE CPR
Explain the formation, significance and treatment of sinus tachycardia dysrhythmias?
Regular and constant R-R Rate >120 P waves uniform and 1 P to 1 QRS complex PR interval 0.12-0.20 seconds and constant QRS is <0.12
Normal sympathetic response to exercise or stress
NOT normal to persist at rest
May be caused by shock, bleeding, fever, pain, anemia, HF, hypoxia, hyperthyroidism, PE
May be caused by: caffeine, atropine, epinephrine, dopamine
Assess pt and treat underlying cause
**tachycardia at rest is an ominous sign
Explain the formation, significance and treatment of sinus bradycardia dysrhythmias?
Regular and constant R-R waves
Rate is <60
P waves are uniform, 1 P wave to 1 QRS complex
PR interval is 0.12-0.20 seconds and constant
QRS complex is <0.12 seconds
May be normal for young pts and athletes May be caused by: Vagal stimulation (parasympathetic) Myocardial Ischemia Elevated intracranial pressure Hypothyroid (myxedema) Medications that may cause this: digitalis, beta blockers, calcium channel blockers etc
Assess pt and treat only if symptomatic: syncope, lowered BP, chest pain, light headedness
Treatment: atropine, pacemaker
Explain the formation, significance and treatment of premature atrial contractions (PAC’s) dysrhythmias?
Regular except premature atrial contractions (PAC’s)
Rate 60-100
P wave is premature, abnormal shape at PAC only
PR interval of ectopic will measure differently than the rest of the beats
QRS is <0.12 seconds
Irritable area in the atria fires before the SA node
Common, typically asymptomatic and benign
May be caused by caffeine, nicotine, HF, pulmonary disease, myocardial ischemia
Frequent PAC’s can lead to atrial tachycardias
Explain the formation, significance and treatment of atrial fibrilation?
Regularity: grossly irregular
Rate: controlled ventricular rate if <100. Rapid ventricular response if >100
P wave: No P waves, only fibrillatory waves
PR interval: unable to measure
QRS complex <0.12 seconds
Chaotic firing of impulses from multiple points in the atria
No atrial contraction, only fibrillation
May be chronic and paroxysmal (come and go)
Risk for thrombus, requires anticoagulation
Multiple causes: cardiac surgery, almost any cardiac disease, pulmonary disease, hypoxia, hyperthyroid
Assess pt. Treatment is aimed at rate control
Meds: amiodarone, calcium channel blockers, beta blockers, digitalis
*consider cardioversion, after anticoagulation
Explain the formation, significance and treatment of bundle branch blocks?
Regularity: regular Rate: 60-100 P waves: normal, uniform, 1 P followed by 1 QRS complex PR interval: <0.20 second and constant QRS complex >0.12 seconds
Delay in conduction through left or right bundle branches
Bundle of His and bundle branches are special fibers that carry impulses quickly
Assess patient, rarely needs treatment
Becomes a significant problem with both left and right bundles are involved.
Describe treatment and rationale for cardioversions?
Cardioversion: Elective or emergent With pulse (Afib, Aflutter, SVT, VT) Cardiac output Conscious patient Synchronized Sedation if possible Energy level lower
Describe treatment and rationale for defibrillation?
Defibrillation Emergent Pulseless (Vtach or Vfib) No cardiac output Unconscious patient Not synchronized No sedation Energy level high
Describe treatment and rationale for implantable cardioverter-defibrillators?
Implanted cardioverter/defibrillator (ICD)
Delivers a chock for VF/VT: synchronized or not as indicated
Procedure and postop care same as pacemaker
Not all ICDs are also pacemakers
Painful when they fire
Patient is admitted for treatment when ICD firing for medication adjustments. Transplant candidate?
Describe treatment and rationale for pacemakers?
Pacemaker Indications:
Bradycardia
Sick Sinus Syndrome (tachy-brady)
Severe heart failure (increase cardiac output)
Many types:
Atrial
Ventricular (generates inverted, wide QRS, skips the bundle branches)
Atrioventricular Sequential (dual chamber)
Operate “on demand”: when heart rate falls below the set rate of pacemaker
Identify EKG changes that accompany hypokalemia?
Conduction depends on sodium-potassium ion pump
Hypokalemia:
Frequent PACs and PVCs
Increased PR intervals and U wave
Risk for afib/flutter or SVT
Risk for prolonged QT or Torsades de Pointes
Identify EKG changes that accompany hyperkalemia?
Conduction depends on sodium-potassium ion pump
Hyperkalemia:
Peaked T waves and increased PR interval =
Widening QRS and ventricular arrythmias = arrest
Identify EKG changes that occur with digitalis (digoxin) therapy?
Digitalis (digoxin) effect appears as a down sloping ST segment depression
Explain the cardiac cycle?
Sinoatrial (SA) node Atrioventricular (AV) junction -AV node -Bundle of His Left bundle branches (2 divisions): left posterior and anterior fascicle Right bundle branch Purkinje fibers
Outline BLS procedures?
Secure the scene
Initial assessment:
Conscious? Breathing? Color?
Not responsive? Yell for help or dial 911
What is the 5 step approach to interpretation of 6 second strip?
Regularity Rate P waves PR Intervals QRS complex
Describe treatment and rationale for various dysrhythmias
BRADYCARDIA
Only treated if symptomatic
-signs of hypoperfusion and low cardiac output
Atropine: 1st line, Inhibits acetylcholine
Dopamine or epinephrine drip: 2nd line
Describe treatment and rationale for various dysrhythmias
SVT
Attempt vagal maneuver first
- increase parasympathetic stimulation
- cough, hold breath, bear down
- carotid massage by provider ONLY
Adenosine
- goal to pause conduction, chemical cardioversion
- short half life, rapid IV push with rapid 20ml flush
Beat blockers
Calcium channel blockers
Amiodarone
-slow rate
Cardioversion if unstable
What are the anti-arrhythmic medications?
Anti-arrhythmic medications
Sodium channel blockers
Beta blockers
Potassium channel blockers
Calcium channel blockers
-diltiazem and verapamil only affect heart rate
Describe treatment and rationale for various dysrhythmias
ATRIAL FIB/FLUTTER
Amiodaron Metoprolol: beta blocker Diltiazem: calcium channel blocker Verapamil: calcium channel blocker Digoxin Sotalol: potassium channel blocker Dofetilide: potassium channel blocker Apixaban: anticoagulant Warfarin: anticoagulant Heparin/Enoxaparin: anticoagulant
Describe treatment and rationale for various dysrhythmias
VENTRICULAR DYSRHYTHMIAS
Lidocaine Beta blockers Amiodarone Magnesium sulfate: for Torsades de Pointes Epinephrine/Adrenaline
Conduction components
Sinoatrial (SA) Node: 60-100 beats/min
Primary pacemaker
Fastest intrinsic rate
Atrioventricular junction (AV): 40-60 beats/min
AV Node and Bundle of His (Bundle of His leads to left and right bundle branches)
Delay the SA impulse for filling: secondary pacemaker (gate keeper)
Ventricle: 20-40 beats/min
Purkinje fibers initiated conduction in the ventricles
Tertiary pacemaker (backup to the backup)
