Basic ECG

Question 1

What does a P wave indicate?

Answer 1

sinus rhythm

Question 2

What does an ST interval indicate?

Answer 2

ischemia

Question 3

What do the intervals indicate?

Answer 3

1. heart rate
2. heart blocks
3. electrolytes

Question 4

Calculating rate?

Answer 4

rate = 300/R-R interval in large squares
rate = 1500/R-R interval in small squares

Question 5

Calculating rate in atrial fibrillation?

Answer 5

1. use the rhythm strip count the number of QRS complexes in 10 seconds and multiply by 6
2. give a range for the shortest distance between QRS and the longest

Question 6

What does a normal sinus rhythm mean?

Answer 6

1. P before every QRS (look lead II strip)
   AND
2. Upright P wave in
   - I, II, aVF
   - Inverted P wave in aVR

Question 7

Normal cardiac axis?

Answer 7

lead 1 - left thumb up
aVF - right thumb up
NB: Both are positive

Question 8

Left axis deviation?

Answer 8

lead 1 positive - left thumb up
aVF negative - right thumb down

Question 9

Right axis deviation?

Answer 9

lead 1 negative - left thumb down
aVF positive - right thumb up

Question 10

What does QRS mean?

Answer 10

Q = if first NEGATIVE deflection
R = first POSITIVE deflection
S = second NEGATIVE deflection

Question 11

What is a Q wave?

Answer 11

A Q wave is any negative deflection that
precedes an R wave
- The Q wave represents the normal left-to-right depolarisation of the interventricular septum

Question 12

Pathological Q waves?

Answer 12

Q waves are considered pathological if:
1. > 40 ms (1 mm) wide
2. > 2 mm deep
3. > 25% of depth of QRS complex
4. Seen in leads V1-3
- Pathological Q waves usually indicate current or prior myocardial infarction

Question 13

Where to locate lateral ischaemia?

Answer 13

1. lead I
2. lead aVL
3. lead V5
4. lead V6

Question 14

Where to locate inferior ischemia on ECG?

Answer 14

1. lead II
2. lead III
3. lead aVF

Question 15

Where to locate septal ischaemia on ECG?

Answer 15

1. lead aVR
2. lead V1
3. lead V2

Question 16

Where to locate anterior ischameia?

Answer 16

1. lead V4
2. lead V3

Question 17

Signs of ischaemia on ECG?

Answer 17

1. hyperactue T waves
2. T wave inversions
3. ST deviations (elevation or depression)
4. deep Q waves

Question 18

Right bundle branch block?

Answer 18

1. second and larger R-wave
2. broad and deep S-wave

Question 19

Left bundle branch block?

Answer 19

1. deep S-wave
2. broad and clumsy R-wave

Question 20

Atrial fibrillation on ECG?

Answer 20

1. narrow QRS
2. irregular intervals
3. undulating or flat P wave

Question 21

Atrial fibrillation management?

Answer 21

1. Manage the UNDERLYING pathology (lung disease, heart failure, sepsis, etc)
2. Consider Anticoagulation to prevent stroke
   - CHADs-2 VASC and HASBLED
3. Consider Rate or Rhythm control
   - Beta Blocker, Calcium Channel Blocker, digoxin, amiodarone
4. Likely get Echocardiogram

Question 22

If patient is unstable in arrythmias what should you do?

Answer 22

cardioversion

Question 23

Supraventricular tachycardia?

Answer 23

1. TACHYCARDIC usually >150bpm
2. No discernible P-waves
3. REGULAR!! (should not vary much at all on continuous telemetry)
4. NARROW!! (this is what makes it “supra” ventricular

Question 24

SVT management in stable patient?

Answer 24

1. Vagal Maneuvers
2. Adenosine (12mg, 12mg)
3. Beta Blocker or Calcium Channel Blocker
4. Direct Synchronized Cardioversion

Question 24

SVT features in an unstable patient?

Answer 24

1. hypotensive 2. altered mental status 3. severe chest pain 4. very short of breath 5. syncope

Question 24

SVT management in unstable patient?

Answer 24

direct synchronized cardioversion

Question 25

Venricular fibrillation management?

Answer 25

dead patient - start ACLS 1. Immediately Start CPR 2. Immediately Apply the AED pads 3. Immediately defibrillate 4. 1 mg Adrenaline q3-5 min 5. continue until patient is out of Vfib

Question 26

Ventricular tachycardia treatment in stable patient?

Answer 26

Immediately apply AED pads If available, amiodarone Direct Synchronized Cardioversion

Question 27

Ventricular tachycardia treatment in an unstable patient?

Answer 27

direct synchronized cardioversion

Question 28

Features of unstable ventricular tachycardia?

Answer 28

hypotensive, altered mental status, hypoxic, severe chest pain, syncope

Question 29

Pulseless patient in VT management?

Answer 29

Start ACLS Immediate CPR Immediate defibrillation 1 mg Adrenaline q3-5 min

Question 30

When to do cardioversion?

Answer 30

Afib, Aflutter, SVT, Vtach with pulse, unstable Vtach but with pulse

Question 31

Who to do cardioversion on?

Answer 31

ANY patient with a PULSE! - Hit the SYNCHRONIZE button on AED - Avoids “R on T” phenomenon

Question 32

When to defibrillate?

Answer 32

Defibrillate = only TWO situations 1. PulseLESS VTach 2. Ventricular Fibrillation - Do NOT hit the synchronize button on AED