Test Review #5 Test CHF, Arrhythmias, PCA-Epidurals

A nurse is administering a beta blocker to a patient who has heart failure. Which statement may be part of the nurse's patient education

"This medication will improve your survival and symptoms of heart failure." Rationale:Beta blockers improve symptoms of heart failure and extend survival. Beta blockers lower heart rates and help do more than managing symptoms.

Sodium: foods/regulate/function

*Foods:* ham, bacon, processed cheese, table salt *Regulate:* KIDNEYS renal absorption or excretion aldosterone increase sodium reabsorption in nephrons *Function:* Regulate ECF volume Maintain blood volume Nerve impulses and muscle contractions

Amiodarone (Cordarone)

*class*: Antiarrhythmic class III, Potassium channel blocker *Indication*: ventricular arrhythmias, SVT, ACLS protocol for v-fib and vTACH *Action*: prolongs action potential, inhibits adrenergic stimulation, slows rate, decreases peripheral vascular resistance causing vasodilation *Nursing Considerations*: - may lead to ARDS, pulmonary toxicity, CHF, bradycardia, hypotension - increases risk for QT prolongation - increases digoxin levels - increases activity of warfarin - monitor EKG - assess for signs and symptoms of ARDS - monitor liver function test - check dosage with another RN - avoid drinking grapefruit juice. Antidysrhythmic agent. Prolongs repolarization, relaxes smooth muscles, decreases vascular resistance. For ventricular fibrillation and unstable ventricular tachycardia. Incompatible with heparin, may be given in PO maintenance dose, monitor for respiratory complications. tx Afib

Atenolol (Tenormin)

*class*: beta blocker, antianginal, antihypertensive *Indication*: hypertension, angina, prevention of MI *Action*: blocks the stimulation of beta1 receptors in the SNS with minimal effect on beta2 receptors *Nursing Considerations*: - Contraindicated in CHF, pulmonary edema, cardiogenic shock, bradycardia, heart block - monitor hemodynamic parameters (HR, BP) - May cause bradycardia, CHF, pulmonary edema - Masks symptoms associated with diabetes mellitus - advise to change positions slowly to prevent orthostatic hypotension - instruct patient on how to take blood pressure Decrease adverse effects of nervous system stimulation. Treat sinus Tachy.

dysrhythmia or arrhythmia

- a pulse with an irregular rhythm. It may consist of random, irregular beats (irregular, irregular) or may have a predictable pattern of irregular beats (irregular regular) - Dysrhythmias may threaten CO - An apical pulse should be assessed when a dysrhythmia is detected and reported to the provider if a new finding

Vfib interventions

-Assess your patient!** •Many things can mimic v-fib on a monitor strip such as electric razor or shivering •You must check your patient! •Treatment must be aggressive and immediate •Start CPR/ACLS •Call a Code Blue •Defibrillate ASAP •Start IV if not already established and hang NS •Notify MD Cardioversion vs Defibrillation differences - defib is used for vfib or pulseless VT, greater joules required for vfib, asynchronous setting cardioversion used to convert RHRs, Aflutter, SVT, lower joules required, synchronous setting Defib: uVoltage required for defibrillation is higher than that used for cardioversion uContinue CPR and medications after defibrillation if rhythm not restored uDefibrillation, CPR, medications continue until stable rhythm returns or determine patient cannot survive

Epidural advantages

1. Eliminates the need for multiple IM injections 2. Minimizes the adverse cerebral and systemic effects Eliminates the analgesic peaks and valleys that usually occur with intermittent IM injections

VTACH

3 or more PVCs in a row Stable w/pulse= amiodarone, unstable w/pulse= cardiovert, No pulse=CPR & defib. Wide QRS = BBB or V tach Pathology u3 or more consecutive ventricular beats uOccurring at rate over 100 bpm uCauses similar to cause of PVCs uUsually associated with Acute Coronary Syndrome uMay also occur MI, long QT syndrome, electrolyte imbalances, cardiomyopathies, structural heart disease, MVP, dig toxicity, CNS disorders. VT is defined as three or more PVCs in a row, occurring at a rate exceeding 100 bpm. The causes are similar to those of PVC. Patients with larger MIs and lower ejection fractions are at higher risk of lethal VT. VT is an emergency because the patient is nearly always unresponsive and pulseless. This dysrhythmia can be seen in patients who have no evidence of cardiac disease. Ventricular and atrial rate: Ventricular rate is 100 to 200/250 bpm; atrial rate depends on the underlying rhythm (e.g., sinus rhythm) Ventricular and atrial rhythm: Usually regular; atrial rhythm may also be regular QRS shape and duration: Duration is 0.12 seconds or more; bizarre, abnormal shape P wave: Very difficult to detect, so the atrial rate and rhythm may be indeterminable PR interval: Very irregular, if P waves are seen P:QRS ratio: Difficult to determine, but if P waves are apparent, there are usually more QRS complexes than P waves The patient's tolerance or lack of tolerance for this rapid rhythm depends on the ventricular rate and severity of ventricular dysfunction.

Potassium

3.5-5.0 mEq/L Give with loop diuretics ex. lasix

prior to administering digoxin

60 seconds, apically Rationale: The nurse must listen to the apical heart rate for 60 seconds. Digoxin should not be administered if the heart rate is less than 60 bpm. Monitor Potassium, calcium, and mag levels- if these are altered it could affect how Digoxin works. HOLD for MI and/or Heart blocks.

Map range (BP)

68-85 (<65=bad)

Tachy

>100 Causes: Fever, dehydration, stress, anxiety, infection, caffeine, pain. Goal is to tx the underlying cause. Treat the underlying cause. Rationale:The best way to treat sinus tachycardia is to treat the underlying cause. Beta blockers may be needed to do this and deep breathing could help, but addressing the underlying cause will solve the problem.

Set up of PCA

A physician order is needed for all of the following: 1. A loading dose (Given IV push at the start of the PCA Therapy) typically 25 mg Demerol or 2 mg of Morphine Sulfate. 2. The appropriate lock out interval 3. The maintenance dose (Also called the basal dose) 4. The amount the patient will receive when the activate the device 5. The maximum amount the patient can receive with a specified time (if an adjustable device is used)

Enalapril (Vasotec)

ACE inhibitor. Slows progression of HF. Antihypertensive. Blocking ACE prevents angiotensin II formation. Result is vasodilation. SE: dry cough (due to build up of bradykinins/vasoconstrinction in lungs), potentially hypersensitivity rxns and angioedema (swelling of lips/tongue/throat). ACE inhibitors - block conversion of angiotensin I to angiotensin II; cause vasodilation and decrease workload of heart; reduce both pre and afterload; captopril, enalapril; side effects - dry cough; ACE inhibitors prevent vasoconstriction and promote diuresis. K is not a worry with these meds. Your ACE inhibitors end in "pril". Make some notes of common ACE inhibitors in your notes. ACE inhibitors-common adverse reactions=dry cough and postural hypotension. Notify MD if these occur. Teach patient how to avoid postural hypotension, change positions slowly, etc.

Prepare for EP and ablation procedure

Advise pt to request pain or anxiety meds, pt under conscious sedation, NPO 8hours prior. NO antiarrhythmic meds for 24 hrs prior. takes 4+8hours. may feel racing HR or feel burning sensation. May continue to have heart palpitations off and on for a few weeks after ablation.

Heparin

Anticoagulant Protamine sulfate is antidote.

Epidural assess pt

Assess the patients respiratory status every 2 hours and record. Assess the patients level of pain using the 0-10 pain scale. Assess for adverse effects such as: Drowsiness, Nausea, Vomiting, Itching, or inability to void, if present, the physician should be notified. Lower extremity strength should be assessed every 2-4 hours. If patient develops a spinal headache after removal of the catheter, they may need to have a blood patch. (Remove 10 mls of venous blood and inject into the epidural space) Performed by physician.

myocardial infarction (MI) per PowerPoint

Atherosclerosis of the coronary arteries is a primary cause of HF, and CAD is found in the majority of patients with HF. Ischemia causes myocardial dysfunction because it deprives heart cells of oxygen and causes cellular damage. Myocardial infarction (MI) causes focal heart muscle necrosis, the death of myocardial cells, and a loss of contractility; the extent of the infarction correlates with the severity of HF. Revascularization of the coronary artery by a percutaneous coronary intervention (PCI) or by coronary artery bypass surgery (coronary artery bypass graft [CABG]) may improve myocardial oxygenation and ventricular function and prevent more extensive myocardial necrosis that can lead to HF

BNP (brain natriuretic peptide) per PP

BNP - BNP elevation significant in diagnosis of HF - BNP > 100ng/mL - abnormal ventricular function or symptomatic HF; greater BNP = more severe HF You should know the BNP levels. The higher the number-you should anticipate that your patient is going to have more symptoms-they are in active HF, they are also more unstable. It will be important to assess for SOB, pulmonary edema, etc. , 300-1000 ng=active HF; will indicate decompensation. <100= normal >100=CHF >300=active CHF

The process from sinus node electrical impulse generation through ventricular repolarization completes the electromechanical circuit, and the cycle begins again.

Cardiac cycle - electrical activity caused by automaticity & mechanical response (contraction) Depolarization active phase = systole Repolarization resting phase = diastole

Potassium foods

Citrus fruits, bananas, watermelon, potatoes, nuts, chocolate, salt substitutes, colas, milk, tomatoes and cooked greens

Procainaminde (Pronestryl)

Class IA Sodium Channel Blocker Treat arrhythmia Increase Duration QRS Increase Duration QT Increase Refractory Period (Decreases automaticity) Treat Atrial flutter Ventricular Tachycardia and fibrillation per PP: Type IA Antiarrhytmic. uPO, IV uAtrial and ventricle arrhythmias, drug induced lupus, PAC, PVC, VT, PAT, after cardioversion AF/A flutter Check pulse and BP after administration of Procanamide Side effects uAllergy, drowsiness, confusion, hypotension, bradycardia, arrhythmias, arrest, N/V Teach to take pulse - want a regular heart rhythm. Moderate depression of depolarization; prolongs repolarization. Treats and prevents atrial and ventricular arrhythmia. S/E: Decreased cardiac contractility, Prolonged QRS, QT.,Proarrhythmic Hypotension with IV administration, Diarrhea with quinidine, constipation with disopyramide, Cinchonism with quinidine, Lupuslike syndrome with procainamide, Anticholinergic effects: dry mouth, urinary hesitancy with disopyramide Nursing Interventions: Observe for HF. Monitor BP with IV administration. Monitor QRS duration for increase >50% from baseline. Monitor for prolonged QT. Monitor N-acetyl procainamide (NAPA) laboratory values during procainamide therapy. If given for atrial fibrillation, ensure that the patient has been pretreated with a medication to control AV conduction. tx of PVC or VT or Afib or PSVT: Before administration of cardiac drugs it is important to know the patient's current blood pressure and pulse. Procainamide is a anti-arrhythmic medication-it blocks electrical signals in the heart that are causing the irregular rhythm

A fib interventions

Client/Family support ECG IV Prepare for CPR Antiarrhythmic medications Vital Signs Treatment depends on cause and duration, patient's S/S, age and co-morbidities Medical conversion = preferred if a-fib is more recent, more effective Electrical conversion = with new Afib and hemodynamically unstable Catheter ablation = minimally invasive procedure, uses high frequency radio waves to destroy tissue at site of arrhythmia; performed in the EP lab; diagnostic cath done to determine location of abnormal tissue; radio waves ablate (destroy) tissue to facilitate normal conduction. uMedical management Cardioversion -Medication or electrical to convert to NSR -Electrical cardioversion :Synchronous :Sync with QRS complex; 150 - 200 joules Pharmacologic treatment -IV ibutilide, procainamide, amiodarone -Beta blockers, calcium channel blockers, digoxin -Antithrombotic therapy - warfarin, rivaroxaban, or apixaban Other Pacemaker or catheter ablation

Vtach clinical manifestations

Clinical manifestations uSymptoms related to decreased cardiac output - hypotension, syncope, pulselessness, unresponsiveness uEKG Rate 100 - 250 bpm Rhythm Regular P wave Usually not visible, if visible not associated with QRS PR interval Not measurable QRS duration > 0.12 sec

Cardioversion vs Defibrillation

Restoration of normal heart rhythm by electrical shock cardioversion - in sync defibrillation - no rhythm, shock whenever. Cardioversion = sync to R wave, drugs - adenosine Afib/flutter, SVT, VT with pulse Defibrillate = not sync VF, VT w/o pulse. Cardioversion: in sync with QRS, used in AFib, atrial flutter, VT w/ a pulse, SVT Defibrillation: not in sync with QRS, used in VFib and VT without a pulse

early CHF symptoms

Decreased exercise tolerance

Electrical activity divided into two phases

Depolarization active phase = systole Repolarization resting phase = diastole

antidote for digoxin

Digoxin immune fab Rationale:Digoxin immune fab is the antidote for digoxin. Vitamin K is the antidote for warfarin, protamine sulfate is the antidote for heparin, and calcium gluconate is the antidote for magnesium toxicity.

measuring a rhythm strip

ECG graph and commonly measured components. Each large box represents 0.20 seconds on the horizontal axis and 5 mm or 0.5 millivolt on the vertical axis. Little boxes are 0.04 seconds 5 lil' blocks equal 1 large block=0.2 seconds going up & down (vertical) the strip measures amplitude or voltage. horizontal line is time & rate going down the strip measures (-) deflection or waveform. Up the strip is (+) deflection or wave form.

Components of the Electrocardiogram

ECG graph and commonly measured components. Each large box represents 0.20 seconds on the horizontal axis and 5 mm or 0.5 millivolt on the vertical axis. Horizontal line is time. Vertical line is voltage. Big square is 5 lil' squares and equals 0.2 seconds. Lil square equals 0.04 seconds. Up is positive, down is negative deflection.

Basic Electrophysiology

ECG tracing indicates electrical activity; automaticity ECG is evidence of electrical activity only

AV block Decision Tree Is there a consistent PR interval YES Are there missing QRS complexes- NO

First degree

IV morphine

HF: IV morphine decreases oxygen demands and oxygen administration helps increase the percentage of inspired air. Morphine Sulfate - decreases violent respiratory stimulant -great respiratory effort contributes little to oxygenation - increased O2 used by respiratory muscles, decreases dyspnea; dilates veins in legs to decrease preload; also relieves anxiety; Morphine decreases preload therefore it also decreases the overall workload of the heart. It can be given to patients with heart failure also for the same reasons. With acute HF, decompensating! Narcan - antagonist;

Bradycardia

HR<60 Causes: sleep, vagal nerve stimuli, Spinal or Brain injury. RX- Beta Blockers ('lol) If asymptomatic: cont to monitor If symptomatic: dizzy, confused, CP RX to treat: IV atropine & transcutaneous pacer (<40bpm)

SVT

HR>150. originates above the (AV) ventricle and not started by the SA node. PP:uAny tachycardia that originates from site above ventricles (usually atria). Associated w/ CAD, HF, lung or thyroid disease. P wave is hidden. Causes: Stress, metabolic disorders, hypoxia, cardiac disease. Must assess if the pt is stable or not Cardioversion vs Defibrillation differences - defib is used for vfib or pulseless VT, greater joules required for vfib, asynchronous setting cardioversion used to convert RHRs, Aflutter, SVT, lower joules required, synchronous setting PSVT- amiodarone May use IV beta blockers, diltiazem or verapamil to help slow rate May consider catheter ablation for long term management. uMedical management uTreatment depends on the cause uVagal maneuvers uMedical management Stable- Shorth term, hemodynamically stable, regular SVT - adenosine Unstable or unable to control with medications- Synchronous cardioversion uOngoing management Oral beta blockers, diltiazem, verapamil

digoxin used to treat

Heart failure Rationale:Digoxin is used to treat heart failure and certain arrhythmias. It does not address hypertension or hypothyroidism, and it is contraindicated in heart block.

Loop Diuretics

I-D-E Furosemide, Bumetanide, Torsemide. Blood pressure and potassium level need to be assessed to determine if the patient is at risk for hypotension or hypokalemia. POTassium wasting- know pts level. If pot. low- can cause arrythmia. Hypotensive d/t fld loss (monitor BP). "at risk for hypotension related to volume loss. This could also cause the patient to become tachycardic." Ototoxicity can be an issue- so push SLOWLY (ya' hear me). Used for Htn, HF, Fld overload, Acute pulm. edema, liver or kidney disease. Works in the Loop of Henley (in kidneys) by blocking the chloride pump (where sodium is reabsorbed).

right sided heart failure

If the right side is affected, fluid will back up into the rest of the body leading to an enlarged liver and spleen, ascites, and dependent edema.

Sinoatrial node (SA node)

In the adult, the electrical impulse usually occurs at a rate of 60 to 100 times a minute. The electrical impulse quickly travels from the SA node through the atria to the atrioventricular (AV) node; this process is known as conduction. The electrical stimulation of the muscle cells of the atria causes them to contract. uPrimary pacemaker uLocated near right atrium near junction with SVC uElectrical impulses uRate of 60 - 100 BPM uImpulses travel from SA - AV node leading to atrial depolarization

Normal cardiac pathway

SA node (rt atrium)-(via Brachmann's bundle and internodal pathways to the) AV node (causes atrial to contract) allows time for atria to contract and fill the ventricles (atrial kick)- bundle of HIS- (right and left) bundle branches- Purkinje fibers (causes the ventricles to contract)

Digoxin

It improves cardiac contractility. Rationale:Digoxin increases cardiac contractility, making the heart pump more effectively. It does not open coronary arteries, work on the peripheral vascular system, or increase heart rate. Used for HF and/or cardiac arrythmias. Hold if HR <60. As this could indicate toxicity. Digoxin - increases ability of heart to contract and improves HF s/s and activity tolerance in patients with mild-moderate HF; Increase contraction force of myocardium - positive inotropic. Helpful with HF; Decreases heart rate -negative chronotropic - helpful with tachycardia, arrhythmias; Decreases conduction speed thru AV node - negative dromotropic - used with arrhythmias; Side effects - Heart - bradycardia, sudden spurts of tachycardia, change in heart rhythm (ventricular) GI tract - anorexia, N/V, abd pain, diarrhea, (anorexia and N/V can be early signs of dig toxicity) CNS - HA, confusion, drowsiness, restless Eyes - yellow or green halos around objects (esp. lights), "snowy" vision, decrease visual acuity Increase automaticity - PVCs (bigeminy, VT) Also can cause atrial tachycardia Normal dig level 0.5-2 (this is one of those lab levels you should know). Electrolyte abnormalities do impact dig levels. Hypokalemia can lead to dig toxicity Digitalization - rapid and slow; IV - 0.5 mg initially followed by 0.25mg BID x 1 day then 0.25 mg QD Maintenance doses - 0.125-0.25 mg/day Digoxin is primarily metabolized in liver with only sm amts excreted unchanged, while digoxin is primarily excreted unchanged with little metabolized in the liver; digoxin is eliminated within 2-6 days; Safe administration at home - teach to take pulse (notify MD if <60); s/s toxicity- hold if blurred vision; Discharge teaching should include having the patient take their own pulse for a full minu

IV lasix & HF

Iv lasix may be given. Need to monitor for dehydration and circulatory collapse so check BP and pulse.

Furosemide (Lasix)

Loop diuretic Block Na and Cl reabsorption in ascending loop Can be used w/ renal impairment Used for pulmonary edema, edema caused by liver/cardiac/kidney disease, htn Also used for hypercalcemia related to kidney stone formation Can cause dehydration, hyponatremia, hypochloremia, hypotension, ototoxicity, hypokalemia (and hyperglycemia, hyperuricemia, decreased Ca and Mg) Can cause dig toxicity due to hypokalemia, lithium toxicity due to hyponatremia Antihypertensives have additive effect NSAIDs reduce diuretic effect Daily weights and I/O Take early in the day

Afib medical management

Medical management Cardioversion Medication or electrical to convert to NSR Electrical cardioversion -Synchronous -Sync with QRS complex; 150 - 200 joules Pharmacologic treatment IV ibutilide, procainamide, amiodarone Beta blockers, calcium channel blockers, digoxin Antithrombotic therapy - warfarin, rivaroxaban, or apixaban Other Pacemaker or catheter ablation

Epidural Analgesia

Medication injected or infused directly into the epidural space, which lies just outside the subarachnoid space where the CSF flows. The drug diffuses slowly into the CSF, which carries it directly into the spinal area - bypassing the blood brain barrier.

VFIB

NO pulse. Start CPR and prepare to Defib, Vfib= Defib

meds for Epidural

Narcotics such as Morphine, Fentanyl or Hydromorphone are administered by either continuous or intermittent infusions alone or in combination with bupivacaine (Marcaine), which is a local anesthetic. This route is recommended because a small amount of medication can be given continuously.

Epidural accessing the catheter

ONLY betadine should be used, Alcohol is neuro toxic.

3rd degree AV block

P wave independent of QRS. Atrials and ventricles don't communicate Rate: regular atrial P wave: Present, upright No relationship between P waves and QRS PR Interval: VARIABLE QRS: variable P-P ad R-R consistent but NO correlation Husband and wife live separate lives and don't communicate atria and ventricles beat independently of each other (P waves have no relation to QRS waves). Dont use Calcium channel blockers.

how to spot SVT on strip

P waves were absent, ventricular rate 200, and the run began and ended abruptly. QRS complex is usually normal in configuration. Can lasts minutes to days, rhythm is usually regualr with an atrial rate of 150-250, and ventricular rate of 75-250.

Patient-controlled analgesia (PCA) & indication

Patient controls the IV delivery of an analgesic (Usually Morphine Sulfate or Demerol), by pushing a button on a delivery system. Indicated for patients who need parental analgesia, typically given to trauma patients post operatively and to terminal cancer patients and others with chronic disease.

Epidural Nursing Considerations:

Patient must sign a consent before undergoing insertion of an epidural catheter. When assisting the physician, patient needs held in knee chest position for insertion. All connections must be taped. Label the epidural catheter with a prominent label stating that the line is an epidural catheter. Cover insertion site with a transparent dressing. The dressing should be changed every 24 to 48 hours or based on hospital policy. Only preservative free narcotics such as Duramorph should be used. Emergency equipment should be available in case of respiratory arrest. Medications administered via epidural catheters diffuse slowly and may take up to 12 hours to wear off. All patients with an epidural catheter MUST have a peripheral IV or a Central Venous Catheter. No parenteral or oral narcotics for up to 12 hours after the Epidural catheter was discontinued.

Coumadin & HF

Patients are started on Coumadin to prevent atrial fibrillation from forming thrombus in the Atria. They will need close lab monitoring, INR should be two to three to be therapeutic.

epidural Contraindications

Patients who have local or systemic infections, neurologic disease, anticoagulant therapy, coagulopathy, spinal arthritis or deformity, hypotension, marked hypertension or allergy to the prescribed drug.

hyperkalemia and heart rhythm

Peaked T represents vulnerable period of repolarization inverted: unstable angina, non-Q MI; peaked, tall: hyperkalemia - see relative refractory period here - time when ventricle responds to another impulse of adequate strength Know foods high in K+ OJ, potatoes. can cause Vfib, PEA,

The electrical impulse that stimulates and paces the cardiac muscle normally originates in the

SA node, also called the sinus node, an area located near the superior vena cava in the right atrium.

HF clinical manifestation

SOB, Fatigue, increased Resp Rate, crackles in lungs, wt gain, swollen feet, hepatomegaly

Multifocal PVCs

SVT pattern of premature ventricular contractions originating from more than one ectopic location. runs of PVCs - danger of decreased cardiac output - risk of V-tach or V-fib. Arise from different foci and appear different in shape from each other. QRS shape and duration: Duration is 0.12 seconds or longer; shape is bizarre and abnormal. When these bizarrely shaped, widened QRS complexes resemble each other, they are called unifocal. When they have at least two different morphologic appearances, they are called multifocal

AV block Decision Tree Is there a consistent PR interval No Is the R-R interval regular? No

Second degree Type I Wenkebock

AV block Decision Tree Is there a consistent PR interval YES Are there missing QRS complexes- Yes

Second degree type II Mobitz II

Sinus Node Arrhythmias

Sinus Bradycardia Sinus Tachycardia Sinus arrhythmia/Sick sinus

Catopril (Capoten)

Slows progression of HF. ace inhib: use: antiHTN Contraind: hypersensitivity SE: Dry non productive cough, HA, Fatigue, Increased k+ Edu: 1h ac, rise slowly, photosensitivity, do not take k+ supps ACE inhibitor. Antihypertensive Lowers BP NOT for OB No NSAIDS Avoid salt substitutes and sodium

HF

Structural or functional cardiac disorders lead to the hearts inability to pump effectively enough to meet metabolic demands. Causes- CAD, MI, HTN, Cardiomyopathy, Valvular disorders, kidney dysfunction, DM, and valvular disorders, high cholesterol, obesity, and cigarette smoking. They body tries to compensate by increasing cardiac output. The heart gets tired, reshapes itself, and doesnt work properly. Diagnosis- echo (normal EF 55-65%), ECG, BNP (>100 suggests HF). Types: Systolic HF - HF w/reduced EF= decreased bld flow from Left ventricle=fld overload (EF<40%=decreased cardiac output and pump failure). Diastolic HF (preserved EF) = Stiff ventricles resist filling= heart works harder, (EF>50%-ventricles unable to relax). Dystolic failure is marked by pulmonary congestion which could show up as dyspnea, orthopnea, and edema, pulmonary hypertension, ventricular hypertrophy, and normal ejection fraction. S/S HF: Dyspnea, Fatigue, Retained fluid. Fatigue is an early manifestation caused by decreased Co and consequent impaired perfusion oxygenation of organs and tissues. Doe and orthopenia are d/t increased pulmonary pressure and fluid buildup. Left side of lung- lungs affected=crackles, diminished lung sounds. Right side affected (aka cor pulmonale)=rest of the body is affected- fld into body; causing blood flow back up in the right atrium this leads to peripheral edema, hepatomegaly, splenomegaly, vascular congestion in the GI tract, and jugular venous congestion. Stages are based on symptoms:Mild to end stage HF. HF pts may also have decreased renal perfusion and urinary output. When they lie down at night, interstitial fluid moved back into the circulation increasing renal perfusion and output.

HF treatment

TX: Arbs and Beta blockers, diuretics help w/symptoms, Digoxin. Treat: Low sodium diet, Promote activity tolerance, monitor fld status w/ daily wts & report wt gain- Pt report any new dependent edema or weight gain of 3 lbs in two days, Adherence to med regimen, management of anxiety and stress. Semi fowlers position, daily weight, administer morphine 2 milligrams IV push.

Interpreting the ECG

The ECG waveform reflects the function of the heart's conduction system in relation to the specific lead. The ECG offers important information about the electrical activity of the heart and is useful in diagnosing arrhythmias. ECG waveforms are printed on graph paper that is divided by vertical and horizontal lines at standard intervals. Time and rate are measured on the horizontal axis of the graph, and amplitude or voltage is measured on the vertical axis. When an ECG waveform moves toward the top of the paper, it is called a positive deflection. When it moves toward the bottom of the paper, it is called a negative deflection. When reviewing an ECG, each waveform should be examined and compared with the others. uECG recording uComposed of waveforms and segments or intervals uWave forms printed on graph paper uGraph paper divided by light and dark, vertical and horizontal lines uLines are placed at standard intervals uTime and rate measured on horizontal axis uAmplitude or voltage is measured in vertical lines uSmall block u0.04 sec uLarge block u5 small blocks u0.2 sec

QT Interval

The QT interval, which represents the total time for ventricular depolarization and repolarization, is measured from the beginning of the QRS complex to the end of the T wave. The QT interval varies with heart rate, gender, and age; therefore, the measured interval may be corrected (QTc) for these variables through specific calculations. The QTc may be automatically calculated by the ECG technology, or a nurse may manually calculate or use a resource that contains a chart of these calculations. The QT interval is usually 0.32 to 0.40 seconds in duration if the heart rate is 65 to 95 bpm. Many medications commonly given in the hospital can cause prolongation of the QT interval (QTc), placing the patient at risk for a lethal ventricular arrhythmia called torsades de pointes. uRepresents total time for ventricle depolarization and repolarization uMeasured from beginning of QRS to end of T wave uVaries with heart rate, gender and age uIf prolonged, can increase risk for torsade de pointes Lethal ventricular dysrhythmia uNormal duration 0.36 - 0.44 sec > 4.7 men; >4.8 women = increased risk for torsade de pointes > 5.0 dangerously prolonged

T Wave

The T wave represents ventricular repolarization (when the cells regain a negative charge; also called the resting state). It follows the QRS complex and is usually the same direction (deflection) as the QRS complex. Atrial repolarization also occurs but is not visible on the ECG because it occurs at the same time as ventricular depolarization (i.e., the QRS). Peaked T represents vulnerable period of repolarization inverted: unstable angina, non-Q MI; peaked, tall: hyperkalemia - see relative refractory period here - time when ventricle responds to another impulse of adequate strength Know foods high in K+ OJ, potatoes Duration not measures Usually same direction as QRS Follows QRS complex Represents ventricular repolarization or electrical recovery

PCA: Nursing Considerations:

The adverse effect of analgesia is respiratory depression, so it is necessary to monitor the respiratory status frequently (at least every 2 hours and record). You need to assess the level of pain using a 0-10 pain scale. With 0 being NO PAIN, and 10 being the WORST pain the patient can imagine. The IV must be checked for infiltration or catheter occlusion. If this is occurring, the patient is not receiving the pain medication. You must assess for Nausea. The narcotics being used have side effects of nausea, if this occurs you must administer anti-emetics along with the analgesic. The patient must know how to properly work the device. The ideal time to teach this is pre operatively, however with most patients there is not time to teach, so you may have to re-teach the material several times. The patient needs to understand that they need enough medication to relieve the pain, but not enough to induce drowsiness. If the patient is drowsy during the day, they are getting too much pain medication. During therapy, monitor and record the amount of analgesic infused, the patients respiratory rate and the patients assessment of the pain itself. If the patient reports insufficient pain relief, notify the doctor. Pain is what the PATIENT says it is. It is NOT for us to judge the amount of pain the patient is reporting.

Advantages of PCA pump

The device prevents accidental overdose by imposing a lock out time between doses (Usually 6-10 minutes). During which time the patient will not receive any analgesic no matter how many times they push the button. 1. No need for IM injections 2. Pain relief tailored to each patient's size and pain tolerance 3. A sense of control over the pain 4. The ability to sleep at night with minimal daytime drowsiness 5. Lower narcotic use compared with patients not using a PCA 6. Improved postoperative deep breathing, coughing and ambulation.

left sided heart failure

The most common form of heart failure: left sided heart failure. It causes backup of blood flow into the left atrium and lungs, leading to increased pulmonary pressure and pulmonary edema.

Who can get a PCA

To receive PCA therapy, the patient must be mentally alert, be able to understand and comply with the instructions and procedures, and have no history of allergy to the analgesic. Patients ineligible for therapy include those with limited respiratory function, a history of drug abuse or chronic sedative or tranquillizer use, or psychiatric disorders.

HF s/s assessment

The nurse should assess the patient's heart rate, evidence of edema, weight changes, skin color, temperature, behavioral changes, chest pain, lung sounds, and also question the patient about paradoxical nocturnal dyspnea which is also called PND. Tachycardia is a compensatory measure to increase cardiac output and heart failure. Edema may occur in dependent areas, liver, abdominal cavity or lungs. Check for degrees of pitting edema in extremities. Initially there may be weight gain from fluid retention, later the clot may be too ill to eat and may lose weight. Skin may be pale or cyanotic and cool. Decreased cerebral perfusion may lead to confusion, restlessness, or memory and concentration problems. Decreased coronary perfusion may lead to angina like pain. Lungs should be listened to for signs of pulmonary congestion, and the patient should be questioned about the presence of a cough and PND to assess for pulmonary involvement from possible left sided heart failure. Daily weights help monitor fluid gain or loss in the client experiencing or at risk for fluid volume overload. High fowler's position helps decrease venous return into increased thoracic capacity. Vital signs should be assessed every hour to every four hours.

ejection fraction (EF) of 35%. What does this indicate?

The patient is in systolic heart failure. Rationale:An EF less than 40% indicates decreased cardiac output and pump failure, which means they have systolic heart failure

Upon assessment, the nurse notes a patient has crackles and dyspnea. What does this indicate?

The patient's left side of the heart is affected. Rationale:Crackles and dyspnea result from a poorly functioning left side of the heart

Heart Electrical Conduction

The structure of the AV node slows the electrical impulse, giving the atria time to contract and fill the ventricles with blood. This part of atrial contraction is frequently referred to as the atrial kick and accounts for nearly one third of the volume ejected during ventricular contraction. uConsists of a transitional cell zone, AV node & His Bundle uAV node lies just beneath right atrial endocardium uTransitional cells delay/decrease impulse rate to ventricles u0.04 sec delay u"Atrial kick" uAlso controlled by sympathetic & parasympathetic systems u"back-up" generates impulses when SA node fails to fire u40-60 bpm

AV block Decision Tree Is there a consistent PR interval No Is the R-R interval regular? Yes

Third degree

Adenosine

Treat SVT- Adenosine Rationale: The goal for treating SVT is to break or slow down the heart rate; adenosine will accomplish this. onset of action is 10 mins, duration is 1-2 hours. IV push over 1-2 seconds. Adenosine slows conduction time and interrupts reentry through the AV node to restore sinus rhythm in SVT. May cause- SOB, dyspnea, Chest pressure, HA. Serious SE- heart block, Ventricular fib, and cardiac arrest. Contraindicated for use in patients w/ heart block, atrial flutter or fib., ventricular tachy, or hx of MI exacerbation of symptoms of asthma, COPD.

Vtach treatment

Treatment for VT must be rapid. May treat with epinephrine or amiodarone May recur if prophylactic treatment is not initiated Ventricular fibrillation may develop. Cardioversion is treatment of choice in unstable, symptomatic VT Any type of VT if patient is unconscious, without a pulse, begin CPR and defibrillate Epinephrine if defibrillation is unsuccessful uTreatment uIdentify and treat underlying cause uMonomorphic Hemodynamically stable (pulse and preserved LV function) -IV procainamide, sotalol, amiodarone, lidocaine Hemodynamically unstable or poor LV function -IV amiodarone or lidocaine, cardioversion uPolymorphic Normal baseline QT -Beta blockers, lidocaine, amiodarone, procainamide =Cardiovert if drug therapy is unsuccessful Prolonged baseline QT -IV magnesium, isoproterenol, phenytoin, lidocaine, pacing -Discontinue any medication that prolongs QT -If medical or pharmacologic treatment is unsuccessful cardiovert

Nesiritide (Natrecor)

Treatment of acutely decompensated HF in clients who have dyspnea at rest of with minimal activity; reduces PCWP and reduces dyspnea; adverse reactions: hypotension is primary side effects and can be dose limiting, arrhythmias, HA, dizziness, insomnia, tremors, paresthesias, abdominal pain, NV; monitor BP, monitor K+; watch for over-response to treatment. Per Power Point: Nesiritide (Natrecor)- vasodilates causing decreased preload and afterload and has a diuretic effect; Can be given by IV bolus of infusion; S/E -hypotension, H/A, nausea, Vtach; Not recommended if BP<90mmHg systolic; Not recommended to draw serum BNP levels til after 2 hrs after Natrecor discontinued; It is a vasodilator, nurse should monitor for hypotension when this med is administered.

After ablation

VS including apical pulse, monitor ECG, auscultate for pericardial friction rub and lung sounds, monitor Neuro, cath site for bleeding, CMS and pulses in the affected leg, MAINTAIN BR w/HOB elevated 30 degrees, maintain affected leg straight for at least 4 hours.

HF Risk factor

Ventricular hypertrophy, Myocardial ischemia, COPD, smoke, A-fib

digoxin toxicity

Visual halos and nausea Rationale: Visual disturbances such as YELLOW halos around objects and nausea are signs of digoxin toxicity. HR<60 could be a s/s.

myocardial infarction (MI)

heart attack; death of myocardial tissue (infarction) caused by ischemia (loss of blood flow) as a result of an occlusion (plugging) of a coronary artery; usually caused by atherosclerosis; symptoms include pain in the chest or upper body (shoulders, neck, and jaw), shortness of breath, diaphoresis, and nausea

Epidural helps

helps manage acute or chronic pain, including moderate to severe postoperative pain. It's especially useful in patients with cancer or degenerative joint disease. Works well because the opiate receptors are located along the entire spinal cord.

Hyperkalemia

high levels of potassium in the blood. usually treatment related, impaired renal function, hypoaldosteronism, tissue trauma, acidosis. M.A.C.H.I.N.E. M - Medications - ACE inhibitors, NSAIDS A - Acidosis - Metabolic and respiratory C - Cellular destruction - Burns, traumatic injury H - Hypoaldosteronism, hemolysis I - Intake - Excesssive N - Nephrons, renal failure E - Excretion - Impaired

Metoprolol

a beta-blocker which is used to slow down the heart. Decrease adverse effects of nervous system stimulation. Treat sinus Tachy. Can cause Sinus brady.

Types of PCA

a reusable battery operated system that the patient operates by pushing a button on the end of a cord. The second type is a disposable, mechanically operated one. It contains an infusor and a unit that is worn like a wrist watch.

transesophageal echocardiogram TEE

an ultrasound test that examines cardiac function and structure by using an ultrasound probe placed in the esophagus, which provides views of the heart structures. ultrasound test that examines cardiac function and structure by using an ultrasound probe placed in the esophagus, which provides views of the heart structures. record of the heart using sound waves performed by inserting the transducer into the esophagus

P wave

atrial depolarization (contraction)

Who inserts Epidural

catheters are inserted by an Anesthesiologist using aseptic technique. Once the catheter is in place the nurse is responsible for monitoring the infusion and assessing the patient.

Asystole

check pt, pulse, and lead placement FIRST line RX= Epi.

pulse pressure

in PP re: HF systolic pressure - diastolic pressure. the difference between systolic and diastolic blood pressure. difference between systolic and diastolic pressure What is pulse pressure? It is simply the systolic blood pressure minus the diastolic blood pressure. Normal pulse pressure 30-40 mm Hg. For example the blood pressure is 132/74-what is the pulse pressure? 58

The electrical stimulation is called

depolarization

mechanical relaxation is called

diastole

EF is preserved in

diastolic heart failure. The heart is not optimally functioning, and the patient has already developed heart failure.

estimate rate using 1 minute ECG strip

divide the total number of squares in the 1 minute strip by the number of similar squares between the R-R interval. Count the number of large squares, b/w one R-R interval and divide 300 by that number or count the number of small squares b/w the R-R interval and divide 1500 by that number. ECG are divided into large, dark lined grids or squares that contain 25 small, light-lines squares (five across and five down). A 1-minute strip contains 300 large squares and 1500 small squares. When rhythm is regular, ventricluar rate may be estimated by counting squares b/w the R-R interval. EX: 9 small squares b/w R-R interval, divide 1500 by 9 for HR of 167. To estimate atrial rate, count squares in the P-P interval

ST segment

early ventricular repolarization

SVT explained to the pt

extra pathways from the node in the atrium to the node in the ventricle, this causes the heart to beat much faster

left ventricular failure

failure of the left ventricle to pump an adequate amount of blood to meet the demands of the body, resulting in a "bottleneck" of congestion in the lungs that may extend to the veins, causing edema in lower portions of the body. pulmonary edema. blood backs up into the lungs causing pulmonary edema > shortness of breath or sense of suffocation

PVC (Premature Ventricular Contraction)

in many cases no P wave followed by a large QRS complex that is premature, followed by a compensatory pause. most common arrythmia

dopamine

inotropin. Tx of acute heart failure and pulmonary edema. Inotropin (Dopamine) - - positive inotropic (increases contractility) - increases renal blood flow (high doses causes vasoconstriction effects); increases BP, will increase HR, will increase renal perfusion. Dopamine is ordered in mcg/kg/min. If I asked you to administer 7 mcg/kg/min. The dopamine bag reads 1000 mg/250 mL. What is the infusion rate on the pump? The patient weighs 85 kg. Calculation: 7*85=595mcg/min*60 (60 minutes in 1 hour)= 35,700mcg/hr-convert to mg= 35.7 mg/hr Desired 35.7/Have 1000mg x 250 mL = 8.925= round to the nearest whole number = The infusion pump will be set at 9mL/hr

Captopril & HF

is an ACE inhibitor it helps prevent further left ventricular hypertrophy. It is considered a standard of care for chronic heart failure. It's been demonstrated to prevent further LVH (left ventricular hypertrophy).

Atrial FIB

looses atrial kick, blood pools in chambers, Causes: increased age, MI, HF, Smoking, cardiac surgery, DM. Physiologic stressors include: hypoxia, infection, hyperglycemia, caffeine, ETOH, smoking/nicotine. NO P wave and the rhythm is irregular, GIVE: Anticoags. May have to cardiovert if the pt is unstable & give RX to control HR. For recurrent or constant AFIB- may need pacemaker. tx: Anticoagulants Rationale: Anticoagulants are expected to be prescribed for a patient with atrial fibrillation to prevent blood pooling in the ventricles and causing clots, which can lead to pulmonary embolism or stroke. Ventricular and atrial rate: Atrial rate is 300 to 600 bpm; ventricular rate is usually 120 to 200 bpm in untreated atrial fibrillation Ventricular and atrial rhythm: Highly irregular QRS shape and duration: Usually normal, but may be abnormal P wave: No discernible P waves; irregular undulating waves that vary in amplitude and shape are seen and referred to as fibrillatory or f waves PR interval: Cannot be measured P:QRS ratio: Many:1 Decreased cardiac output due to loss of "atrial kick" and decreased ventricular filling When ventricular rates are 120-200, you should expect that your patient may experience some s/s such as hypotension and dizziness. Treatment depends on cause and duration, patient's S/S, age and co-morbidities Medical conversion = preferred if a-fib is more recent, more effective Electrical conversion = with new Afib and hemodynamically unstable Catheter ablation = minimally invasive procedure, uses high frequency radio waves to destroy tissue at site of arrhythmia; performed in the EP lab; diagnostic cath done to determine location of abnormal tissue; radio waves ablate (destroy) tissue to facilitate normal conduction.

ECG

no sleep the night before, meals allowed, no stimulants/tranquilizers for 24-48 hours before. may be asked to hyperventilate 3-4 min and watch a bright flashing light. watch for seizures after the procedure. uECG tracing indicates electrical activity; automaticity uCardiac cycle - electrical activity caused by automaticity & mechanical response (contraction) uElectrical activity divided into two phases uDepolarization active phase = systole uRepolarization resting phase = diastole uECG is evidence of electrical activity only uPEA (pulseless electrical activity) The electrical impulse that stimulates and paces the cardiac muscle normally originates in the SA node, also called the sinus node, an area located near the superior vena cava in the right atrium. The electrical stimulation is called depolarization, and the mechanical contraction is called systole. Electrical relaxation is called repolarization, and mechanical relaxation is called diastole. The process from sinus node electrical impulse generation through ventricular repolarization completes the electromechanical circuit, and the cycle begins again.

heart failure (HF)

occurs when the heart is unable to pump enough blood flow to meet the needs of the body and can cause a number of symptoms, such as shortness of breath, leg swelling, and exercise intolerance. condition in which there is an inability of the heart to pump enough blood through the body to supply the tissues and organs with nutrients and oxygen. disorder that occurs when the heart is unable to effectively pump the quantity of blood required by the body

atrial fibrillation

occurs when the normal rhythmic contractions of the atria are replaced by rapid irregular twitching of the muscular heart wall. rapid, random, ineffective contractions of the atrium

Stable SVT

prepare to cardiovert

HF Pathophysiological Factor

pulm. vascular congestions, inadequate perfusion of systemic circulation, right ventricular infarction, ineffective right ventricular contraction

Electrical relaxation is called

repolarization

U wave

repolarization of the purkinje fibers

Beta blockers HF

reverse LVH and are considered a standard of care for chronic heart failure.

Brain natriuretic peptide (BNP)

serum lab value can assist in diagnosing heart failure. A BNP level over 100 suggests heart failure

the mechanical contraction is called

systole

heart rhythm

the regularity or irregularity of the occurrence of heartbeats; the pattern of heartbeats

PR interval

time from SA node stimulation to ventricular contraction

QT interval

total time for ventricular depolarization and repolarization

Bundle Branch System

uHis bundle connects with distal portion of AV node & perforates septum uDivides into right & left bundles uPurkinje fibers located @ ends - penetrate myocardium uPurkinje cells responsible for rapid conduction of impulses through ventricles u15- 40 bpm The electrical impulse then travels very quickly through the bundle of His to the right and left bundle branches and the Purkinje fibers, located in the ventricular muscle.

PR Interval

uIsoelectric line from beginning of P wave to beginning of QRS complex uRepresents time required for SA node stimulation, atrial depolarization and conduction through the AV node before ventricular depolarization uNormal duration 0.12 - 0.20 sec in adults prolonged; heart block shortened; nodal Measure from onset of P to onset of QRS The PR interval is measured from the beginning of the P wave to the beginning of the QRS complex and represents the time needed for sinus node stimulation, atrial depolarization, and conduction through the AV node before ventricular depolarization. In adults, the PR interval normally ranges from 0.12 to 0.20 seconds in duration.

U Wave

uMay or may not be present If seen, follows T wave Smaller than P wave uRepresents Purkinje fiber repolarization uOften seen in hypokalemia, hypertension or heart disease The U wave is thought to represent repolarization of the Purkinje fibers; although this wave is rare, it sometimes appears in patients with hypokalemia (low potassium levels), hypertension, or heart disease. If present, the U wave follows the T wave and is usually smaller than the P wave. If larger in amplitude, it may be mistaken for an extra P wave. elevated:MI; depressed: ischemia/hypoxia - see absolute refractory period here - ventricle won't respond to another impulse regardless of strength

Per PP Determine Rhythm Regularity

uMeasure distance between 2 consecutive R waves and 2 consecutive P waves Determines ventricular and atrial regularity uCompare distance between R-R or P-P Consistent = regular Varies = rhythm irregular uNormal rhythm Regular The rhythm is often identified at the same time the rate is determined. The RR interval is used to determine ventricular rhythm and the PP interval to determine atrial rhythm. If the intervals are the same or if the difference between the intervals is less than 0.8 seconds throughout the strip, the rhythm is called regular. If the intervals are different, the rhythm is called irregular. Once the rhythm has been analyzed, the findings are compared with and matched to the ECG criteria for arrhythmias to determine a diagnosis. It is important for the nurse not only to identify the arrhythmia, but also to assess the patient to determine the physiologic effect of the arrhythmia and identify possible causes. Treatment of an arrhythmia is based on clinical evaluation of the patient with identification of the arrhythmia's etiology and physiologic effect, not on its presence on ECG alone.

P-P and R-R Intervals

uMeasure from beginning of 1 P or R wave to beginning of next P or R wave uP-P represents atrial rate and rhythm uR-R represents ventricular rate and rhythm. The PP interval is measured from the beginning of one P wave to the beginning of the next P wave. The PP interval is used to determine atrial rate and rhythm. The RR interval is measured from one QRS complex to the next QRS complex. The RR interval is used to determine ventricular rate and rhythm.

Vtach medical management

uMedical management uAssess patient's tolerance of rhythm uAssess LOC, BP and pulse uDetermine identifying features Monomorphic Polymorphic uStable or unstable Several factors determine the initial treatment, including the following: identifying the rhythm as monomorphic (having a consistent QRS shape and rate) or polymorphic (having varying QRS shapes and rhythms), determining the existence of a prolonged QT interval before the initiation of VT, any comorbidities, and ascertaining the patient's heart function (normal or decreased). If the patient is stable, continuing the assessment, especially obtaining a 12-lead ECG, may be the only action necessary. The patient may need antiarrhythmic medications, antitachycardia pacing, or direct cardioversion or defibrillation. Procainamide, amiodarone, sotalol, and lidocaine are all antiarrhythmic medications that may be considered based upon type of VT (e.g., monomorphic or polymorphic), clinical presentation, and patient comorbidities (e.g., impaired cardiac function, acute MI).

Quality CPR (cardiopulmonary resuscitation)

uPush at correct depth and maintain rate (push hard and fast) uDecrease interruptions-make sure you completing 2 breaths in less than 10 seconds and return to compressions uAvoid excessive ventilation There is research that supports completing chest compressions only and if respirations not delivered, patient outcomes are not impacted. This may be encouraged for the lay public that may fear acting and starting CPR because they do not want to do the mouth to mouth respirations.

ST Segment

uRepresents early ventricular repolarization uLasts from end of QRS to beginning of T wave uIsoelectric or flat Use PR segment as reference for baseline uIdentified as change in thickness or angle of the terminal position of QRS complex J point uCovers completion of ventricular depolarization to beginning of repolarization uAnalyzed to identify if above or below isoelectric line to evidence myocardial ischemia The ST segment, which represents early ventricular repolarization, lasts from the end of the QRS complex to the beginning of the T wave. The beginning of the ST segment is usually identified by a change in the thickness or angle of the terminal portion of the QRS complex. The end of the ST segment may be more difficult to identify because it merges into the T wave. The ST segment is normally isoelectric (see later discussion of TP interval). It is analyzed to identify whether it is above or below the isoelectric line, which may be, among other signs and symptoms, a sign of cardiac ischemia.

P Wave

uRepresents electrical activity starting in sinoatrial node (SA node) and spreading through atria (atrial depolarization) leading to atrial contraction Presence of P wave indicates impulse originates in the atria Shape uMay be positive, negative or biphasic, depending on the lead viewed uShape is consistent when impulse originates in SA node. The P wave represents the electrical impulse starting in the SA node and spreading through the atria. Therefore, the P wave represents atrial depolarization. It is normally 2.5 mm or less in height and 0.11 seconds or less in duration. P wave - absent impulse below atria - abnormal configuration, atrial irregularity - abnormal placement AV node, heart block, nodal pattern

QRS Complex

uRepresents ventricular depolarization uFollows PR interval uQ - first negative deflection after P wave uR - first positive deflection after P wave uS - first negative deflection after R wave uMeasured from beginning of QRS to end of QRS uNormal duration Less than 0.10 sec The QRS complex represents ventricular depolarization. Not all QRS complexes have all three waveforms. The Q wave is the first negative deflection after the P wave. The Q wave is normally less than 0.04 seconds in duration and less than 25% of the R-wave amplitude. The R wave is the first positive deflection after the P wave, and the S wave is the first negative deflection after the R wave. When a wave is less than 5 mm in height, small letters (q, r, s) are used; when a wave is taller than 5 mm, capital letters (Q, R, S) are used to label the waves. The QRS complex is normally less than 0.12 seconds in duration.

per PP Analyzing the Rhythm Strip

uSix second method Locate 3 second markers along top of ECG paper Count number of R waves (ventricular rate) or P waves (atrial rate) occurring between 2, 3 second markers (6 seconds) Multiply the number of waves by 10 for heart rate uLarge box method Count number of large boxes between 2 consecutive R waves or P waves and divide into 300 Example: 4 large boxes between 2 R waves; 300/4 = 75 bpm uSmall box method Count number of small boxes between 2 consecutive R waves or P waves and divide into 1500 Example: 10 small boxes between 2 R waves; 1500/10 = 150 bpm uNormal heart rate 60 -100 bpm Heart rate can be obtained from the ECG rhythm strip by several methods. A 1-minute rhythm strip contains 300 large boxes and 1500 small boxes. Therefore, an easy and accurate method of determining heart rate with a regular rhythm is to count the number of small boxes within an RR interval and divide 1500 by that number. If, for example, there are 10 small boxes between two R waves, the heart rate is 1500/10, or 150 bpm; if there are 25 small boxes, the heart rate is 1500/25, or 60 bpm. An alternative but less accurate method for estimating heart rate, which is usually used when the rhythm is irregular, is to count the number of RR intervals in 6 seconds and multiply that number by 10. The top of the ECG paper is usually marked at 3-second intervals, which is 15 large boxes horizontally. The RR intervals are counted, rather than QRS complexes, because a computed heart rate based on the latter might be inaccurately high. The same methods may be used for determining atrial rate, using the PP interval instead of the RR interval.

Normal QRS Deflections

uV1 - negative uV2 - negative uV3 - biphasic uV4 - biphasic uV5 - positive uV6 - positive uLead I - positive uLead II - positive uLead III - small, positive uaVR - negative uaVL - positive uaVF - positive

UNstable SVT

vagal maneuvers, Adenosine

QRS

ventricular depolarization

T wave

ventricular repolarization

PVC

wide QRS, comes from low in the ventricles, Causes: electrolyte imbalance, hypoxia, caffeine or ETOH. Pt may feel skip beat. TX: Goal to tx underlying cause, Several in a row or more than a few+ Investigate

Rhythm Strip Analysis Format

• Regularity (Rhythm) • Rate • P Waves • PR Intervals • QRS Complexes Ventricular and atrial rate: 60 to 100 bpm in the adult Ventricular and atrial rhythm: Regular QRS shape and duration: Usually normal, but may be regularly abnormal P wave: Normal and consistent shape; always in front of the QRS PR interval: Consistent interval between 0.12 and 0.20 seconds P:QRS ratio: 1:1 When measuring intervals or durations it is important to understand that the smallest block on your ECG strip is 0.04 seconds. So when you are measuring a PR interval, you look for the beginning of the "P" to the beginning of the "QRS". How many blocks does this cover? Each block is 0.04 seconds-a normal PR interval is 0.12-0.20.