Chapter 8: Rhythm Recognition Flashcards
What is the typical position for the defibrillator pads?
Beneath right clavicle
Left mid axillary line
What alternative position for defibrillator pads can be used and when?
Anterior posterior positions
Permanent pace maker in right pectoral region
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
<0.12s
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 axonal rhythm occur and what is it?
Occur in dying patients
Slow irregular wide ventricular complexes
Does;t usually generate pulse
Often progress to asystole
