EKG interpretation/dysrrhythmias

5 step EKG interpretation

1) Rate- normal sinus rate (60-100)

-for regular rhythm: divide # of small boxes between R waves by 1500-= heart rate

-for irregular rhythm= multiply # of R waves by 10

2) Rhythm- regular or irregular (count small boxes from one R wave to the next, for a 6 second strip; if same number of boxes between R waves, then the rhythm is regular)

3) P wave- are all P waves in a 6 second strip the same in size/shape; is the P wave inverted? (if all the same, then normal)

4) PR interval- (normal= 0.12-0.20 seconds) from P wave to start of QRS complex, count the small boxes between and multiply by 0.04

-if the number you get is between 0.12-0.20, then normal

-if greater than 0.20, AV block

-if lower than 0.12, junctional block

5) QRS complex- count boxes from Q wave to S wave, then multiply by 0.04

-normal= 0.06-0.12

interventions for sinus bradycardia and sinus tachycardia:

sinus bradycardia= treat only if symptomatic; if symptomatic, treat with atropine

sinus tachycardia= only treat if symptomatic; vagal maneuver (carotid massage, baring down, beta blockers, or calcium channel blockers

symptoms of sinus bradycardia and tachycardia:

sinus bradycardia- pale skin, cyanosis, signs of low oxygen

sinus tachycardia- palpitations, chest pain, SOB, dizziness, sweating/fainting etc.

ATRIAL FIBRILLATION

WHAT- rapid, disorganized twitching of the atrial mm; SA node has lost control

(causes pooling of blood or "swooshing" that can lead to blood clots)

huge risk for blood clots

S/S = signs of low oxygen

INTERVENTIONS- slow HR and restore electrical conduction, organize pumping in atrium, and prevention of clots

(anticoagulants, BB's, cardiac ablation, digoxin, electro cardioversion

ATRIAL FLUTTER

WHAT- similar to A fibrillation, but instead of the rhythm being irregular, A flutter has a regular rhythm but still a fast rate

*SA node has lost control as primary pacemaker

CAUSES- lung problems such as COPD, pulmonary HTN, valvular disease, open heart surgery, or hyperthyroidism

S/S = low oxygen symptoms

INTERVENTIONS- anticoagulants to prevent clots, BB's to slow HR, cardiac ablation, digoxin to increase contractility slow HR, and electro cardioversion if all else fails

PREMATURE ATRIAL CONTRACTION (PAC)

WHAT- an atrial contraction that occurs early and before the next normal impulse

S/S = none in mild cases; more severe cases show low BP and a pulse deficit

INTERVENTIONS- treat underlying cause (stress, sepsis, or stimulants), discontinue/decrease digoxin if that's what is causing, correct electrolyte imbalance (hypokalemia), and/or give amiodarone, lidocaine or procainamide

VENTRICULAR TACHYCARDIA

WHAT- very fast rhythm that begins in ventricles

* SA and AV node both fail to generate an impulse

*ventricles are not pumping effectively

S/S = very low to no oxygen being pumped to body (signs of low oxygen)

CAUSES- stimulants, médication toxicity, and electrolyte imbalances (low magnesium or potassium), or cardiac injury such as an MI

INTEVRENTIONS- if patient has pulse, give amiodarone and do cardioversion

-if no pulse, immediate defibrillation, lidocaine/amiodarone given, and normal cardiac arrest procedure performed (CPR)

VENTRICULAR FIBRILLATION

WHAT - primary deadly rhythm; chaotic pattern of electrical activity in ventricles

*little to no cardiac output or oxygen out to body

*SA and AV node both fail to generate impulse

CAUSES- cardiac injury, med toxicity (digoxin), electrical imbalances (untreated V. tach), and/or electrolyte imbalances (low magnesium)

S/S = low oxygen (usually unconscious patient)

INTERVENTIONS- immediate defibrillation, start CPR, give epinephrine, lidocaine, and amiodarone (if shock doesn't work)

SUPRAVENTRICULAR TACHYCARDIA (SVT)

WHAT- episodes of rapid HR that starts above ventricles

*SA node fires normally, but the impulse somehow backs up into atrium instead of going into ventricles, leading to double the beats per minute

CAUSES- stress, sepsis, stimulants, CAD, myocarditis, rheumatic fever, or CHF

S/S = low oxygen symptoms

INTEVRENTIONS- vagal maneuver (baring down/carotid massage), adenosine (patient must consent and doctor must be present), cardiac ablation, and/or electrocardioversion

PREMATURE VENTRICULAR CONTRACTION (PVC)

WHAT- contractions in the ventricles that occur before next normal impulse

CAUSES- stimulants, stress, sepsis, CAD, CHF, myocarditis, COPD, and/or rheumatic fever

S/S = pulse deficit, low BP, and patient stating "my heart skipped a beat"

INTEVRENTIONS- treat underlying cause, decrease/discontinue digoxin, correct electrolyte imbalances, give procainamide, lidocaine or amiodarone

SECOND DEGREE AV BLCOK (TYPE 1) (aka wenckebach)

WHAT- when 1 or more (but not all) atrial impulses fail to conduct into ventricles

*biggest indicator is a prolonged P wave

S/S = low oxygen symptoms

INTEVRENTIONS- stop/decrease drugs that lower HR, stimulate AV node with dopamine, atropine, and epinephrine, or pacemaker placement

SECOND DEGREE AV BLOCK (TYPE 2) (aka mobitz II)

WHAT- (worse than type 1), electrical signals from atria to ventricles are delayed/blocked

*almost always a disease of the distal conduction system (bundle of his and purkinje fibers)

S/S = low oxygen symptoms (chest pain, SOB, etc.)

INTEVRENTIONS- stop/decrease drugs that lower HR, give atropine/dopamine/epinephrine, or pacemaker placement

THIRD DEGREE AV BLOCK (aka complete heart block)

WHAT- impulses from the atrium are completely blocked at AV node and cannot get through to ventricles

*little to no oxygen being pumped to body

*worst AV block

S/S = low oxygen symptoms (dizziness, SOB, chest pain etc.)

INTERVENTIONS- stop/decrease drugs that lower HR, give atropine/dopamine/epinephrine, and/or pacemaker placement

BUNDLE BRANCH BLOCK (BBB)

WHAT- delay/block in the bundle branches on the pathway that sends electrical impulses to left and right sides of ventricles

S/S= usually asymptomatic; if symptoms, would show signs of low oxygen

CAUSES OF R. SIDED BBB- CAD, MI, open heart surgery, drug toxicity, PE, or HTN

CAUSES OF L. SIDED BBB- HTN, tachycardia, aortic stenosis, cardiomyopathy

INTERVENTIONS- treat underlying cause, pacemaker placement, or cardiac resynchronization

signs of Atrial Fibrillation on EKG:

1) rate= over 100 bpm

2) rhythm= irregular

3) P wave= absent (atria are not contracting)

4) PR interval= absent

5) QRS= normal

signs of Atrial Flutter on EKG:

1) rate= 75-150 bpm

2) rhythm= regular

3) P wave= absent (atria are not contracting)

4) PR interval = absent

5) QRS= normal

signs of PAC on EKG:

1) rate= can be any rate

2) rhythm= regular BUT interrupted due to early P wave

3) P wave = early/different (may even be hidden)

4) PR interval= shortened (but still between 0.12-0.20 seconds)

5) QRS= normal

signs of Ventricular Tachycardia on EKG:

1) rate= 100-250 bpm

2) rhythm= regularly spaced/even (looks like tombstones)

3) P wave= absent

4) PR interval= absent

5) QRS= wide and even

signs of Ventricular Fibrillation on EKG:

1) rate= unknown/indistinguishable

2) rhythm= chaotic waveform (looks like squiggly lines)

3) P wave= absent

4) PR interval= absent

5) QRS= absent

signs of SVT on EKG:

1) rate= 150-250 bpm

2) rhythm= regular

3) P wave= buried in T wave

4) PR interval= not measurable

5) QRS= normal

signs of PVC on EKG:

1) rate= depends

2) rhythm= irregular

3) P wave= absent

4) PR interval = absent

5) QRS= wide and bizarre

signs of Type 1 Second degree AV block on EKG:

1) rate= variable

2) rhythm= irregular

3) P wave= present but late

4) PR interval= cycles; PR gradually gets longer until P wave is blocked

5) QRS= normal

signs of Type 2 Second degree AV block on EKG:

1) rate= atrial rate faster than ventricular rate (more P waves than QRS's)

2) rhythm= irregular

3) P wave= many (more than QRS complexes)

4) PR interval= normal OR prolonged

5) QRS= wide

signs of Third degree AV block on EKG:

1) rate= 40-60 bpm

2) rhythm= regular but P waves and QRS contract independently

3) P wave= normal

4) PR interval= varies

5) QRS= normal OR wide

signs of a Bundle Branch Block on EKG:

1) rate= depends

2) rhythm= regular

3) P wave= normal

4) PR interval= normal

5) QRS= wide/longer