Dysrhythmia questions and answers 2023 updated

Dysrhythmia questions and answers 2023 updatedmechanical and electrical activity correlation between the electrical and mechanical functions of the heart electrical activity stimulates the heart to contract ECG shows both functions electrical pulse = action potential videos what's the difference between telemetry and ECG? ECG is diagnostic while telemetry monitors rhythm changes Cardiac monitoring is used to diagnose dysrhythmias, chamber enlargement, Mycoardial ischemia or infarction, monitor effects of electrolye imbalances of medication administration. Cardiac electrical activity can be monitored by an ECG. 12 - lead, ambulatory (Holter monitoring), or telemetry. For continuous monitoring or telemetry most monitors use 2-4 electrodes. These electrodes create an imaginary line, called a lead, that serves a reference point from which the electrical activity is viewed. A lead is like an eye of a camera - it has a narrow peripheral view, looking only at the electrical activity directly in front of it. The electrical impulse that travels through the heart can be viewed by means of electrocardiography, the end product of which is an electrocardiogram. Each phase of the cardiac cycle is reflected by specific waveforms on the screen of a cardiac monitor or on a strip of ECG graph paper. In other words, it represents the function of the heart's conduction system. ECG can show ischemia, infarction, enlarged cardiac chambers, electrolyte imbalances, drug toxicity. placing telemetry leads white goes on right black opposite white "grass under snow" (green) "fire under smoke" (red) brown in the middle changes leads for shower (remove old, shower, add new) placing EKG electrodes 12-lead EKG, we only put on 10 leads 4 limb 2 saddle the sternum 4 on the left side of the chest client needs to remain still and breathe normally properties of cardiac cells conductivity contractility automaticity excitability refractoriness Conductivity: transmit electrical impulses across cell membranes and from cell to cell. Contractility: A/V muscle cells shorten fiber lengths to propel blood forward during contraction. Automaticity: Ability of cardiac cells to initiate an impulse (primary pacemaker cells). Excitability: Ability to respond to stimulus and then depolarize. Refractoriness: Cells unable to respond to stimulus until recovered from previous stimulus (repolarization). Although the SA node and AV node ordinarily initiate the pacing of the heart, all of the cells have the capability of doing so. Depolarization: normally negatively charge cells developing a positive charge. Depolarization produces mechanical contractions. arrhythmia no rhythm dysrhythmia abnormal rhythm classified by the site of origin: -SA node -Atrial -AV node -ventricular PQRST complex one heart beat P wave SA node fires at the beginning the wave itself shows the atria contracting P wave: atrial depolarization (contraction); PR interval conduction from SA to AV normal is 0.12-0.20 sec (3-5 dots) PR interval: beginning of P wave to end of PR interval: atrial depolarization, AV delay and travel time to purkinje fibers. 0.12 - 0.20. QRS complex conduction from AV node to Purkinje fibers ventricular contraction normal is < 0.10 sec (2.5 dots) QRS complex: ventricular depolarization (contraction). Time required for depolarization of both ventricles: 0.04-0.10. QT interval QT interval: ventricular depolarization + repolarization. QT may be prolonged with some medications; can be a dangerous sign. ST segment ST segment: early ventricular repolarization. Should not be elevated more than 1 mm or 1 line above or depressed more than 0.5 mm (1/2 line below). Elevated ST segment indicates an MI: STEMI or NSTEMI. Depressed means ischemia. T wave ventricles are relaxed and filling during this time, they won't respond to stimulation we want a wide T wave, but not one that's too tall T wave: ventricular repolarization: resting and cannot respond to a stimulus. Rhythm Strip Analysis 1. Determine Regularity (of R waves): -determine underlying rhythm (regular or irregular) -"March it across" (calipers) and make sure the spacing between each QRS peak is equal 2. Calculate the (ventricular) rate: -dots = 0.04 sec -boxes = 0.2 sec -hashtags = 3 sec -if patient has a regular rhythm, count the peaks between 3 hashmarks (6 seconds) and multiply by 10 to get a rough estimate of the heart rate OR -count # of small squares between 2 consecutive R ways and divide this number into 1500 (1500/23 boxes = 65 bpm) 3. Assess the P waves: -present? -P for every QRS (1:1)? -are they all the same? 4. Measure the PR interval: -normal (0.12-0.20)? -consistent? -pattern? 5. Measure the QRS complex: -normal (<0.10)? -are they all the same? normal sinus rhythm HR 60-100bpm regular rhythm P waves are identical and present before each QRS PR interval 0.12-0.20 QRS <0.12 when rhythms are NOT normal Cardiac dysthrmias are heartbeat disturbances (beat formation, beat conduction). The terms dysrhythmias and arrhythmias are used interchangeably. In reality, dysrhythmia means abnormal rhythm and arrhythmia means absent rhythm. Dysrhythmias are classified by the site of origin: SA node, Atrial, AV node, ventricular. ectopy FLB (funny little beats) causes of dysrhythmia cardiac: -valve issues -cardiomyopathy -heart failure -MI -conduction defects pulmonary: -hypoxia -acidosis other: -electrolyte imbalance (K+) -blunt trauma -drugs -caffeine -electrical shock -hypoglycemia -hypothermia -clots