Chapter 8: Rhythm Recognition Flashcards
What is the typical position for the defibrillator pads?
- Beneath right clavicle
- Left MAL
What alternative position for defibrillator pads can be used and when?
Position:
1. Anterior posterior positions
When:
1. Permanent pace maker in right pectoral region
2. Chest wall trauma
What is the normal length of a PR interval?
- 3-5 small squares
- 0.12-0.20s
What is the normal length of a QRS?
- < 3 small squares
- < 0.12 s
If QRS < 0.12s- originates above Bundle of His
If QRS > 0.12s - orginates from ventricles or supraventricular rhythm w/ BBB
What happens to the QRS in a bundle branch block?
Widens
How can VF be classified?
Fine or Coarse - depending on amplitude of complexes
What is likely the diagnosis if there is a regular rhythm with intermittent irregularity?
Ectopic beats
Describe how atrial flutter may be seen?
- Regular repetitive positive deflection
- With a saw tooth appearance
- Often around 300 beats/min
- Usually in inferior leads - II, III, AVF
- Can be 2:1, 3:1 etc.
How may retrograde atrial activation be spotted?
- Inverted p waves
- In II and aVF
What is the immediate treatment for polymorphic VT?
Same as for VF:
- Shock
- Adrenaline every 3-5 mins
- Amiodarone after 3rd shock
What is the normal QT interval and how is it measured??
- Start of Q to end of T
- It is corrected to calculate QTc = QT/square root of RR
- Should be >0.35s and <0.44s in males, <0.46s in females
What can cause long QT?
- Hypokalaemia
- Hypomagnasaemia
- Amiodarone (avoid in pt. with Torsades)
- Hypocalcaemia
- Hypothermia
What are some reversible causes for PEA?
- Severe fluid depletion or blood loss
- Cardiac tamponade
- Massive PE
- Tension pneumothorax
What are the main causes for Bradyarrhythmias?
- Heart block - 1st, 2nd Mobitz I and II, 3rd
- Escape rhythm’s - SA node fail
- Agonal rhythm’s
When does agonal rhythm occur and what is it?
- Occur in dying patients
- Slow irregular wide ventricular complexes
- Doesn’t usually generate pulse
- Often progress to asystole