EKG Exam Notes PDF

Here is the information from the images converted into a markdown format: ### Conduction Pathway 1. Sinus Node 2. Interatrial Tracts 3. Atrium 4. Internodal Tracts 5. AV node 6. Bundle of His 7. Bundle Branches 8. Purkinje Fibers * SA = 60-100 * AV = 40-60 * Vent = 20-40...

Here is the information from the images converted into a markdown format: ### Conduction Pathway 1. Sinus Node 2. Interatrial Tracts 3. Atrium 4. Internodal Tracts 5. AV node 6. Bundle of His 7. Bundle Branches 8. Purkinje Fibers * SA = 60-100 * AV = 40-60 * Vent = 20-40 * **Internodal Tracts**: * Atrium * Ventricle * Depolarization (Contraction). * 0.1 second between Atria + Ventricles. * This delay allows for a coordinated movement of blood through the v * Atria beat together * Ventricle beat together. ### ECG Placement Leads * A lead is a (recording) view of the electrical activity of the heart from a specific angle. * Some of the electrodes communicate with each other which is why there are 12 leads. #### Limb Electrodes * Right Arm (white) * Left Arm (black) * Right Leg (green) * Left Leg (red) #### Precordial * V1 - 4th ICS R of sternum * V2 - 4th ICS L of sternum * V3 - Midway btwn V2 + V4 * V4 - 5th ICS mid clavicular line * V5 - 5th ICS anterior axillary line * V6 - 5th ICS mid axillary line #### MCL: Modified Chest Lead * For continuous monitoring 1. Placement * Abdomen * R shoulder * L shoulder * Aligns w/ heart's natural electrical axis. Clear visual of P wave. * **Lead I**: Measures electrical activity between R arm( - ) and L arm( + ) * **Lead II**: Measures R arm( - ) and L leg( + ) * **Lead III**: Measures L arm( - ) and L leg( + ) * Can dx diagnose heart conditions arrhythmias & ischemia ### Interpretation Guidelines (EKG) | | | | :---- | :---- | | | 0.20 | | | 0.5 mV | | | 0.04 | | | =0.1mV | * 5 blocks = 1 second ### Eight Steps 1. Measure HR. 2. Examine R-R int 3. Examine P wave 4. Measure PR int. 5. Determine if each P wave is followed by QRS. 6. Examine / measure QRS complex. 7. Examine and measure QT int 8. Diagnose Rhythm * **R-R int:** * If R-R are reg int (constant) Rhythm = regular * If not = irregular * **Examine P waves:** * Smooth / upward deflection * If altered / missing = SA is primary pacemaker * **Measure PR:** * PR - Measures am of time an impulse travels from atrium to ventricle. * Measure beginning o P wave to beginning of QRS. * Normal range: 0.12 - 0.20 or 3-5 little boxes. * Greater than 5 boxes suggests conduction delay (AV node). * **QRS** * Precede each QRS = stable 1:1 relationship btwn these two waves. ### Rhythms Originating in the Atria * **PAC - Premature Atrial Complexes** * premature beat that originates in the SA Node | Atrial rate @ reg rate than a premature beat btwn * Due to irritation of Atria & automaticity.(Lead II) * Narrow QRS complex * Upright P wave * Different morphology - P wave * Coin't on back of page * **Wandering Atrial Pacemaker / Multifocal Atrial Tachycardia - (WAP) (MAT)** * pacemaking impulses originate from at least 3 different foci in the atria. * Each focus produces own Pwave resulting in 3 different shape of Pwave. * WAP = slow atrial arrhythmia * MAT = Rapid * **Rate** * WAP < 100 (btwn 50-60 s) * MAT > 100 * Regularity * Phases: 3 diff shapes * Int: PR varies * QRS < 0.12 s * Adv effects MAT & CO if HR is too fast. * Tx WAP - none MAT - Beta blockers / ca chan blockers if signs of & CO ### Ectopic beats * Extra of premature beats * "Skipping / Fluttering! ### Examine / measure QRS complex * Normal range: 0.12 s (3 little boxes) * Typically: 0.6 - 0.10 s * Do they look identical? * Abnormally wide? * delayed conduction through bundle branches ### Measure QT int. * Less than ½ of R-R int.< 0.40 s * ↑ HR QT short * ↓ HR QT lengthens ### Atrial in origin? * Matching upright PS, atrial Rate >160 @ rest or * No P waves at all; wavy or sawtooth baseline btwn QRSs OR * Premature abnormal P wave w/or wlout QRS interrupting another Rhythm OR * HR ≥ 130, Rhythm regular, P waves discernibile (may be present but unsure)