Module 4

Question 1

What is “sinus rhythm”?

Answer 1

a rhythm the originates from the SA node

Question 2

What is the usual rate of the sinus rhythm ?

Answer 2

60-100 BPM

Question 3

What is the rhythm of sinus rhythm?

Answer 3

Regular

Question 4

What does the P wave look like in a sinus rhythm?

Answer 4

Upright/postive in lead 2, and occurs before every QRS complex

Question 5

What is the length of the PR interval?

Answer 5

0.12-0.20 Secs

Question 6

What is the length of the QRS complex?

Answer 6

0.10 secs or less

Question 7

What is a “Sinus arrhythmia”?

Answer 7

Is the lack of normal sinus rhythm

Question 8

Where does the sinus arrhythmia originate from?

Answer 8

The SA node

Question 9

How do you know your patient is in a sinus arrhythmia?

Answer 9

The heart rate increases as the patient breathes in, and decreases as the patient breaths out

Question 10

Why does the rate change with breathing in a sinus arrhythmia?

Answer 10

Due to changes in intrathoracis pressure that occurs during the respiratory cycle

Question 11

How does the rhythm look on the strip?

Answer 11

Irregular firing but the waveform looks normal

Question 12

Is there any conduction problem with a sinus arrhythmia?

Answer 12

None present, and no potential problems

Question 13

What causes sinus arrhythmia?

Answer 13

Can be due to heart disease but is not usually a pathological rhythm

Question 14

Is there any changes to O2 supply and demand in this rhythm?

Answer 14

This problem does not pose a problem in regards to O2 supply and demand

Question 15

What interventions can be done for a sinus arrhythmia?

Answer 15

Document the rhythm

but no interventions are needed unless the rate drops below 60 BPM

Question 16

What is the rate of sinus arrhythmia?

Answer 16

60-100 BPM

Question 17

What is the rhythm in sinus arrhythmia?

Answer 17

Irregular, HR changes with respiratory cycle

Question 18

What does the P wave look like in sinus arrhythmia?

Answer 18

Positive/Upright in lead 2, one P before each QRS complex

Question 19

What is the length of the PR interval?

Answer 19

0.12-0.20 secs

Question 20

What is the length of the QRS complex?

Answer 20

0.10 secs or less

Question 21

What is “sinus

bradycardia”?

Answer 21

Heart rate is regular but is less than 60 BPM

Question 22

Where does SB originate from?

Answer 22

From the SA node

Question 23

What type of rhythm is sinus

bradycardia?

Answer 23

Regular

Question 24

What type of conduction problems are present in a sinus

bradycardia?

Answer 24

SA node is firing at a rate less than 60 BPM

Question 25

What is the cause of a sinus | bradycardia?

Answer 25

Always assess the patient first! Medications such as digoxin and beta-blockers can cause this Issues with the SA node

Question 26

What are the implications for O2 supply and demand in a sinus bradycardia?

Answer 26

Since there is a decrease in HR, there is a decrease in CO | Assess your patient for signs and symptoms of decreased cardiac output

Question 27

What are some interventions for sinus | bradycardia

Answer 27

Check your patient first Atropine to help increase HR (parasympahooyltic) Temporary transvenous pacemaker may be needed

Question 28

What is the rate of sinus bradycardia?

Answer 28

Less than 60 BPM

Question 29

What type of rhythm is sinus bradycardia?

Answer 29

Regular

Question 30

What does the P wave look like in sinus bradycardia?

Answer 30

Positive, upright in lead 2. right before a QRS complex

Question 31

How long is the PR interval in sinus bradycardia?

Answer 31

0.12-0.20 secs

Question 32

How long is the QRS complex in sinus bradycardia?

Answer 32

0.10 secs or less

Question 33

What does failure of an impulse from the SA node called?

Answer 33

Sinus arrest or sinus pause

Question 34

Where do you see this type of failure of the SA node?

Answer 34

A gap in between QRS complexes

Question 35

What does the gap look like in a sinus arrest?

Answer 35

The gap between the QRS complex is greater than 3 seconds

Question 36

What does the gap look like in a sinus pause?

Answer 36

The gap between QRS complex is less than 3 seconds

Question 37

Is there a conduction problem with a sinus pause/gap?

Answer 37

Yes, if the SA node does not fire

Question 38

What can cause a sinus gap or pause?

Answer 38

They are caused by depression of the SA node including - hypoxia - hypothermia - drug toxicity - vagal stimulation - electrolyte imbalance - infections such as myocarditis - ischemia to the conduction system itself - disease of the RCA (RCA supplies blood to the SA node)

Question 39

How does the sinus pause/arrest affect oxygen supply and demand?

Answer 39

- If the rhythm is transient, the patient should be asymptomatic - With frequent pauses, it causes a lower HR and therefore lower CO, which can lead to a loss of atrial kick and preload is affected and leading to further decreased CO

Question 40

What are some interventions for sinus pause/arrest?

Answer 40

- Based on patient assessment - Atropine/possible pacing - Know unit guidelines