HAPS--Cardiac Rhythms Flashcards
(43 cards)
1
Q
Conduction
A
SA Node AV Node Supra ventricular Bundle of His (A/V bundle) Purkinje fibers
2
Q
SA node
A
normal pacemaker of the heart
intrinsic rhythm 60-100
3
Q
AV node
A
- receives electrical impulse of SA node
- delays impulse before conduction
- enables atrial contraction to be completed before ventricles contract
- can become the pacemaker
4
Q
Supraventricular
A
-area of AV junctional tissue located above the ventricles
5
Q
bundle of his (A/V bundle)
A
- branches into right and left bundles
- continues into purkinje fibers
6
Q
purkinje fibers
A
- conduct impulse to ventricular muscle cells
- cause ventricular depolarization and contraction
7
Q
P wave
A
atrial depolarization
8
Q
QRS complex
A
ventricular depolarization
-P wave and QRS wave follow each other (married)
9
Q
T wave
A
ventricular re-polarization (resting state of the heart)
10
Q
EcG rules
A
rhythm, rate, P waves, P-R interval, QRS interval
11
Q
Cardiac measurements
A
- each small square = 0.04 seconds
- each large square (surrounds 5 small squares) =0.20 seconds
12
Q
How to determine the rate for irregular rhythms
A
- count the number of complexes in 6 seconds of time and multiply by 10. This will equal bpm.
- markings are on the top of strip indicating 3 seconds
13
Q
How to determine the rate for regular rhythms
A
-count the number of small squares between the R-R (top of QRS complex) and divided by 1500
OR
-count the number of big blocks between R-R and divide into 300.
14
Q
Analyze the P waves
A
- P waves indicate atrial depolarization usually from 1 focus–the SA node
- are p waves present
- is there 1 P wave for every QRS
- are p waves regular
15
Q
Measure the PR interval
A
- start at beginning of P wave to the R wave (normally 0.12 to 0.20 seconds)
- this measures the electrical impulse through the atria and the delay that normally occur at the AV node
16
Q
QRS duration
A
- measure from the at the Q and end of S
- normal duration is 0.04-0.10 seconds
- do all QRS segments measure within limits
- do all QRS look the same
- the QRS represents ventricular depolarization
17
Q
Normal Sinus Rhythm
A
- rhythm is regular
- rate is 60-100
- P waves are rounded and come before each QRS and all look alike
- PR interval is between 0.12-0.20 seconds
- QRS interval is less than 0.10 seconds
18
Q
Sinus Dysrhythmias
A
Bradycardia
Tachycardia
19
Q
Bradycardia
A
- slower than normal heart rate
- beat is originating from SA node
- rhythm is regular, but rate is less than 60
- P waves are smooth and regular, QRS 0.06-0.10
- no symptoms unless its so slow that cardiac output is reduced
20
Q
Tachycardia
A
- heart rate is greater than 100 bpm, originating from SA node
- rate is regular, P waves are regular and rounded, PR interval 0.12-0.20, QRS is 0.06-0.10
- if HR is rapid for long period, patient may experience angina or dyspnea.
21
Q
Atrial dysrhythmias
A
PAC
supraventricular tachycardia
atrial fibrillation
22
Q
Ventricular dysrhythmias
A
PVC
Bigeminy PVC
ventricular tachycardia
ventricular fibrillation
23
Q
First Degree AV block
A
- PRI greater than 0.20
- rhythm remains regular
- martial problems start
24
Q
Second degree AV block
A
- progressive lengthening of PRI until one P wave is not conducted through to the ventricles
- separation of the couple begins
25
Third Degree AV block
- no conduction of atrial impulses
- atria and ventricles beat independently and P:QRS have no sequential relation
- now divorced
26
Cardioversion
- used for dysthythmias that do not respond to drug therapy
- pads are placed where you would listen to S1 and S2
- patient is sedated and shocks start with a range of 25-50 joules
- consent is required and patient is sedated
- assess cardiac response after first synch has been delivered
- turn oxygen back on if it had been turned off
27
defibrillation
- delivers an electrical shock to reset the hearts rhythm
- indicated in V-Fib or pulse less V-tach
- pads are placed on patients chest to prevent burning and promote conduction of electrical charge
- pads are placed where you would listen to s1 and s2
- total of 3 shocks can be initially given
28
Medications used for Atrial Fibrillation
Calcium channel blockers
- diltiazem ( Cardizem)
- amiodarone (Cordarone)
29
What is digoxin given for?
CHF and atrial fibrillation
30
PAC's
| prematrue atrial contractions
- "early beat" that atria fires an impulse due to irritability and a premature beat results
- impulse does not always originate from SA node. rate has irregularities
- P wave often looks different or it may be buried in the T wave.
31
Causes and treatments of PAC's
- stress, fatigue, anxiety, inflammation, infection, caffeine/nicotine/alcohol.
- treatment is aimed at cause
- usually no symptoms but will feel palpitation
- medications used are anti-dysrhythmic medications and teach to avoid stress and caffeine.
32
Supraventricular Tachycardia
- occurs with rapid stimuation of atria at a rate of 100-280
- P waves may not be visible
- depending on whether it is sustained or not sustained will determine if patient is symptomatic or not
33
Atrial fibrillation
- atrial rate of 350-500 can occur
- AV node blocks most impulses so ventricular rate is much lower than atrial rate
- no definable P waves because the atria are fibrillating or quivering
- there is increased risk for thrombus formation which can result in stroke d/t heart dilation and blood pooling
- usually tell if patient has this as their pulse is irregular and thready
- cardio-version or medications are usually indicated.
34
Atrial fibrillation
- occurs with patients who have HTN, heart failure, CAD, have had TIA's or strokes
- cardiac output can decreased as much as 20-30%
- treatment includes anti-dysrhythmic medications such as beta blockers, diagxin, cardizem or amiodarone.
- anticoagulants are given d/t increased risk for embloli
35
premature ventricular contractions
| PVC's
- originate in ventricles from an ectopic focus (a site other than SA node)
- ventricles are irritable and fire prematurely before the SA node normally would--result is widened strange looking QRS complex
36
Bigeminy PVC's
- bigeminy=every other beat is a PVC
- trigeminy=every 3rd beat is a PVS
- couplet=there is a pair of PVC's
- can be felt by patient and usually cause by too much caffeine, nicotine, or alcohol
37
PVC's
- make special concerns with patients who are having PVC's and have a history or current issue of MI's as this could potentially progress to life threatening v-tach or v-fib
- palpate peripheral pulses during an episode to ensure adequate perfusion
38
V-tach
- occurs when there are 3 or more PVC's in a row
- ventricles become pacemaker of heart
- is serious depending on how long it lasts
- intermittent is less than 15 seconds
- sustained is longer than 15-30 seconds
39
V-Tach
- V-tach can cause cardiac arrest
- assess patients ABC's, LOC, and oxygen level
- administer oxygen
- amiodarone, lidocaine and magnesium sulfate are used
40
V-fib
- when many ectopic ventricular foci fire at same time
- ventricular activity is chaotic with no definite waves
- there is NO contraction
- no cardiac output or pulse
- fatal if not ended with 3-5 minutes
41
V-fib
- patient will become faint, lose consciousness, pulse-less, and apneic
- NO HEART SOUNDS
- seizures can occur and pupils become fix and dilated
- defibrillation is REQUIRED
- medications include: vasopressin, epinephrine, amiodarone, lidocaine, magnesium sulfate
42
Asystole
- FULL CARDIAC ARREST
- no shocking
- medication:epinephrine and atropine
43
medications for PAC's
epinephrine
