Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.

Remove ads
Don't know
remaining cards
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards

Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Block 4 - EKG

EKG information and interpretation

Automaticity The cell's ability to spontaneously initiate an impulse
Excitability indicates how well a cell responds to an electrical stimulus
Conductivity how well the cell contracts after receiving a stimulus
Electrical activity precedes mechanical activity
Mechanical activity cannot occur without electrical activity
Electrical activity can occur without being followed by mechanical activity
EKG a graphic recording of the electrical activity generated by the functioning heart.
EKGs help to identify Primary conduction abnormalities, dysrhythmias, cardiac hypertrophy, pericarditis, electrolyte imbalances, MI - site & extent
SA Node The hearts main pacemaker 60-100 BPM
SA Node location right atrium near the superior vena cava
AV Node location lower part of right atria near the tricuspid valve
AV Node delays cardiac impulses for protection of ventricles against excessively high atrial rates; allows atria to contract and empty blood into ventricle at end of diastole (atrial kick)
Tissue surrounding AV Node contains pacemaker cells that fire at 40-60 BPM
Bundle of HIS located in septum between the 2 ventricles
Purkinje Fibers Terminal portion of the conduction system, third pacemaker 20-40 BPM
Atria Low pressure chambers, reservoirs for respective ventricles
Right ventricle low pressure chamber, sends deoxygenated blood to lungs
Left ventricle high pressure chamber, send oxygenated blood to body
Tricuspid valve AV valve between right atrium & right ventricle
Mitral valve AV Valve between left atrium & left ventricle
Atrioventricular (AV) Valves Tricuspid & Mitral, unidirectional, closure produces S1 (Lub) sound
Semilunar Valves Pulmonic & Aortic, unidirectional, closure produces S2 (dub) sound
Pulmonic valve Between right ventricle and pulmonary artery
Aortic valve Between left ventricle and aorta
Depolarization discharge of energy that accompanies the transfer of electricle charges across the cell membrane
Repolarization return of electrical charges to their original state of readiness
Baseline a starting or resting line of the EKG
Wave a deflection from the baseline
Biphasic a deflection wtih both positive and negative components
P Wave first deflection; represents atrial depolarization
PR interval from the beginning of the P wave to the onset of the Q wave; represents conduction of the impulse through the atria to the AV node (0.12 - 0.2 seconds)
QRS Complex represents ventriclular depolarization; 0.06 - 0.12 seconds
ST Segment End of S wave to beginning of the T wave
PR interval too long > 0.2 seconds; indicates AV block
PR interval too short <0.12 seconds; junctional rhythm
T wave Repolarization of the ventricles
QRS Complex too long >0.12 seconds; something slowing conduction; could be caused by bundle branch block, hypertrophied ventricle
ST Segment depression (below baseline) hypoxia, ischemia, electrolyte issues, healing MI
ST segment elevation (above baseline) Infarction (MI)
QT Interval beginning of Q wave to end of T wave; 0.36 - 0.44 seconds
T wave tall & tented Hyperkalemia
T wave shape should be upright and slightly rounded
QT Interval >0.44 seconds BAD; puts pt at risk of developing V-tach or toursades
Normal heart rate 60-100 BPM
Tachycardia >100 BPM
Bradycardia <60 BPM
Cardiac Output Stroke volume X Heart Rate
Sinus Tachycardia Interventions Treat the cause; rest, oxygen, analgesics, fluids, diuretics, beta-blockers, digoxin
Causes of Sinus Tachycardia CHF, hypovolemia, hypotension, anemia, exercise, fever, hypoxia, pain, anxiety, hyperthyroidism, pulmonary embolism, AWMI, response to drugs that stimulate heart, alcohol, caffeine, nicotine
Causes of Sinus Bradycardia Athletes with well conditioned hearts, digitalis, beta blockers, calcium channel blockers, sleep, elevated ICP, inferior wall MI, vagal stimulation caused by vomitting or severe pain, hypothyroidism, hypothermia
Sinus Bradycardia Interventions Identify underlying cause; If symptomatic - Atropine, pacemaker, dopamine
Causes of PACs Coronary and valvular heart disease, dig toxicity, hyperthyroidism, elevated catecholamine levels, acute respiratory failure, COPD, fatigue, anxiety, electrolyte imbalances, ischemia, MI, early CHF, alcohol, nicotine, caffeine
PAC interventions If symptomatic, focus on eliminating the cause or may treat with antiarrhythmics
Causes of Atrial Fibrillation Valvular disorders, hypertension, CAD, MI, cardiomyopathy, COPD, CHF, rheumatic heart disease, hyperthyroid, dig intoxication
Interventions for Atrial Fibrillation Control (slow) rate and improve cardiac output. If symptomatic - syncronized cardioversion. Diltiazem, Verampamil, Digoxin, beta blockers to slow conduction through AV node. Other anti-arrhythmic drugs once ventricular response controlled.
Danger of Atrial Fibrillation Stroke - clot forms and breaks loose, anticoagulant therapy unless contraindicated (heparin/coumadin)
Interventions for Ventricular Tachycardia in consious stable patient order 12 lead EKG to determine type of tachycardia
Interventions for Ventricular Tachycardia in unstable patient Call for help, Start CRP, Immediate synchronized cardioversion followed by drug therapy
Interventions for Ventricular Tachycardia in pulseless patient ACLS - shock, CPR for 2 minutes, shock & vasopressors, shock and antiarrhythmic (amiodarone, lidocane, magnesium)
Ventricular Tachycardia Lethal dysrhythmia - Assess pt, call for help, start CPR
Ventricular Fibrillation (V Fib) Interventions Assess Pt, call for help, start CPR, Code Cart/ACLS
Causes of V Fib MI, Myocardial ischemia, hypokalemia, hyperkalemia, hypercalcemia, cocain toxicity, hypoxia, hypothermia, acid-base imbalance, electric shock
Asystole Interventions Assess, call code, CPR, intubate, O2, Vasopressin, epinephrine, atropine, pacemaker (confirm in more than 1 lead)
Causes of asystole Severe metabolic deficit, acute respiratory failure, MI, severe electrolyte disturbances, massive pulmonary embolism, electric shock, cocaine OD
Asystole Flatline - ventricular standstill - no electrical activity, no contraction, no cardiac output
Ventricular Fibrillation Lethal Rhythm - rapid disorganized depolarizations of the ventricles characterized by a lack of organized electrical impulse, conduction and ventricular contraction.
Created by: bonjoy