HAN 417 - Final

When should Epinephrine be given?

-cardiac arrest

-heart failure

-shock

When should Amiodarone be given?

-vfib

-vtach

When should Atropine be given?

-symptomatic bradycardia

When should Adenosine be given?

supraventricular tachycardia (SVT)

When should Dilitiazem be given?

rapid afib or rapid aflutter

When should Metoprolol be given?

rapids afib or rapid aflutter

What does the PR interval represent?

the time from the onset of atrial depolarization to ventricular depolarization

What does the PR segment represent?

the normal delay in the AV node

What does the QT interval represent?

the total time for the ventricles to depolarize and repolarize

What does the ST segment represent?

ventricular repolarization

What does the P-wave represent?

atrial depolarization

-initiates atrial contraction

What do normal P-waves tell us?

that the SA node is functioning properly

What does the QRS complex represent?

ventricular depolarization

What does a normal QRS complex tell us?

normal ventricular conduction

Why is the QRS complex the most prominent wave on an EKG tracing?

because of the large muscle mass of the ventricles

What does the T-wave represent?

ventricular repolarization

-recovery phase

What is a positive deflection?

any waveform ABOVE the isoelectric line

What is a negative deflection?

any waveform BELOW the isoelectric line

What is a biphasic deflection?

a waveform that has both positive and negative deflections

What is the path of electrical conductions in the heart?

1. SA node

2. Internodal atrial conduction tract and Bachmann's Bundle

3. AV node

4. Bundle of his

5. left and right bundle branches

6. Purkinje fibers

Which leads are considered bipolar leads?

I, II, III

Which leads are considered augmented leads?

aVR, aVL, aVF

Which leads are considered precordial?

V1-V6

-ride your green bike on pavement

How do you measure the timing of the PR interval and the QRS complexes using the small boxes?

-each small box is 0.04 seconds

-each big box is 0.20 seconds

How do you calculate HR on an EKG strip?

Count the number of QRS complexes

-if its a 6 second EKG strip (multiple by 10)

Characteristics of normal sinus rhythm:

-rate: 60-100 bpm

-rhythm: regular

-P-waves: normal, upright, before every QRS complex

-PR interval: 0.12-0.20 seconds

-QRS complex: normal, duration of less than 0.10 seconds

Characteristics of sinus bradycardia:

-rate:

-rhythm:

-P-waves:

-PR interval:

-QRS complex:

Characteristics of sinus tachycardia:

Characteristics of sinus arrhythmia:

Characteristics of normal sinus rhythm with sinus arrest:

What is synchronized cardio-version?

delivery of a timed electrical shock to reset an abnormal rhythm

What wave are synchronized cardio-version shocks synchronized with?

R-wave

True or false: Once a shock is delivered, you must press "sync" before delivering another shock.

true

When do we use synchronized cardio-version?

-unstable SVT

-rapid afib/aflutter

-vtach WITH a pulse

What kind of shocks are given when delivering defibrillation?

random shocks that do NOT line up with any specific wave

What should be done IMMEDIATELY after a patient goes into vfib or vtach cardiac arrest after interventions such as pacing or cardioversion?

defibrillation

What is transcutaneous pacing?

external cardiac pacing

What does transcutaneous pacing consist of?

2 electrode pads placed AP on the patient's chest to conduct electrical impulses through the skin to the heart

When is transcutaneous pacing used?

-symptomatic bradycardia

-unstable heart blocks

What is the distinguishing feature of wandering atrial pacemaker rhythm?

the changing P wave morphologies across the rhythm strip

-3 or more different P-wave morphologies

In what ways do the P-waves vary in a wandering atrial pacemaker rhythm?

shape, size, or direction as the pacemaker "wanders" between multiple sites

What is multifocal atrial tachycardia?

the same characteristics as WAP, (3 or more different P-waves morphologies) except at a rate greater than 100 bpm

What is premature atrial conduction?

-the premature beat occurs IN ADDITION to the regular beat (you must include both when diagnosing the rhythm)

-normal sinus rhythm with PAC(s)

What is atrial flutter?

-V shaped waveform with a "SAWTOOTH" pattern

What is atrial fibrillation?

-irregularly irregular

-quivering atria which produces wave deflections (fibrillatory waves)

What is a distinguishing feature for atrial fibrillation?

a wavy baseline between irregular QRS complexes and non-discernable P waves

Where do junctional rhythms originate?

in the AV node

What happens when the AV junction is functioning as the primary pacemaker?

the impulses travel backwards to depolarize the atria

-inverted P waves on lead II

AV junction pacemaker cell characteristics:

-firing rate: 40-60 bpm

-automaticity

-inverted P waves

General characteristics of a junctional rhythm:

-1 of 3 patterns for P waves (immediately before QRS, immediately after QRS, hidden within QRS)

-short PR interval

-normal QRS complex

-inverted P waves

What is a premature junctional contraction?

an early beat that originates in an ectopic pacemaker site in the AV junction

-underlying rhythm AND the PJC should be in the diagnosis

What is an accelerate junctional rhythm?

-a rhythm that originates in an ectopic site in the AV junction discharging impulses at 60-100 bpm

IS "accelerated" fast enough to be considered tachycardia?

No

Characteristics of ventricular arrhythmias:

-no p waves

-impulses do NOT enter the normal conduction pathway

-slower conduction of impulses (travel from muscle fiber to muscle fiber)

-wide QRS ( > 0.12 seconds or 3 small boxes)

Where do ventricular arrhythmias originate from?

BELOW the bundle of his

Characteristics of PVCs:

-premature

-p waves are NOT associated with PVC

-WIDE QRS

-ST segment and T wave are usually in opposite directions

-compensatory pause followed the PVC

What is an idioventricular rhythm?

a very slow rhythm originating in the ventricles at a rate of 30-40 bpm

Characteristics of an idioventricular rhythm:

-no P waves

-non measurable pR interval

-wide QRS

-ST segment and T wave are in opposite direction of QRS complex

-usually a continuous terminal rhythm but may occur intermittently

What does an idioventricular rhythm usually progress to?

asystole

-very difficult to resuscitate

What is an agonal rhythm?

when the rhythm becomes irregular, slower, and QRS' begin to widen and deteriorate into indistinguishable waveforms

What is the discharging impulse for an accelerated idioventricular rhythm?

50-120 bpm

What differentiates AIVR from IVR and VTach?

heart rate

What is ventricular tachycardia?

-originates from an ectopic site in the ventricles discharging impulses at a rate of 140-250 bpm

What are the two types of vtach?

-monoprhic

-polymorphic

What is monomorphic vtach?

-QRS complexes have the same morphology

-occurs as a continuous rhythm or intermittent runs of 3 or more consecutive ventricular beats

What is the most common form of vtach?

monomorphic

What is polymorphic vtach?

-QRS complexes have different morphologies in the same lead

What is torsades de pointes?

-a type of POLYMORPHIC vtach

-"twist" around the isoelectric line

What is ventricular fibrillation?

rhythm originating in multiple sites in the ventricles characterized by erratic electrical activity which takes over control of the heart

-quivers instead of contracting (wavy irregular deflections with no discernable waves or complexes)

True or false: Vfib is always considered symptomatic.

true

What is coarse vfib?

vfib with LARGE deflections

What is fine Vfib?

vfib with SMALL deflections

What is asystole?

-no ventricular activity which means no QRS complexes

-straight line/ "flatline"

What is pulseless electrical activity (PEA)?

-clinical situation where there is no organized electrical activity seen on the monitor but there is NO PALPABLE PULSE

What are AV blocks?

a group of rhythms that originate in the sinus node and will have NORMAL p-waves

What kinds of rhythms are described as AV block?

rhythms in which there is a delay or block in the conduction of impulses from the atria to the ventricles

What are the classifications of AV blocks?

-1st degree

-2nd degree/Mobitz type I

-2nd degree/Mobitz type II

-3rd degree

How do you measure AV blocks?

1st degree AV block

regular rhythm conducting to ventricles but takes a while

-PR interval greater than .20 seconds

2nd degree/Mobitz I AV block

P waves that occur in regular intervals and PR intervals that progressively get longer and longer until an impulse is not conducted to the ventricles

-"wider, wider, wenckebach"

2nd degree / Mobitz II AV block

-"If the P's don't get through, Mobitz II"

-P to P is ALWAYS regular

If the location of AV block is at bundle of his:

the duration of QRS will be normal

If the location of AV block is at bundle branches:

the duration of QRS will be wide

3rd degree AV block:

-complete heart block

-atria and ventricles beat INDEPENDENTLY of each other (different pacemakers)

- "If the P's and Q's don't agree = Type 3/complete AV"

What are the atria typically paced at?

60-100 bpm

What are the ventricles typically paced at?

40-60 bpm, sometimes less

Which bipolar lead goes on the right arm?

white

Which bipolar lead goes on the right leg?

green

Which bipolar lead goes on the left arm?

black

Which bipolar lead goes on the left leg?

red

Which precordial lead goes on the 4th ICS to the right of the sternum?

V1 (red)

Which precordial lead goes on the 4th ICS on the left side of the sternum?

V2 (yellow)

Which precordial lead goes between V2 and V4?

V3 (green)

Which precordial lead goes on the 5th ICS at the mid-clavicular line?

V4 (blue)

Which precordial lead goes on the anterior axillary line, horizontal to V4?

V5 (orange)

Which precordial lead goes on the the mid-axillary line, horizontal to V4 and V5?

V6 (purple)

What goes in the top left box on an 12 lead?

patient information

What goes in the middle box on a 12 lead?

measurements

What goes on the right box on a 12 lead?

analysis

When does a 12 lead switch from leads I, II, and II to augmented and precordial leads?

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