EKG interpretation steps

Blurb: P's & PR, Q & RR, Rate & Rhythm, Axis, Width & Height

1 - Rate:
6 sec strip: count all QRS complexes then x10
10 sec 12-lead EKG: count all QRS complexes then x6

2 - Rhythm: PQR
P's? --- Is P always before QRS? Does QRS always follow P?
       --- Is P the same in every P presented?
       --- Is PR interval the same in every beat?

Qs? --- Is Q width normal? (<0.11sec. or <2.5ss)

Rs?--- Regularity: All cycles/beats repeat the same? If not, any predictability of 2:1, 3:2, 4:1, etc.?

3 - Axis: skip this for now

4 - Width: PR-Q-RR

PR segment width:  
          Normal: 3ss-5ss (less than 1 large box) or 0.12-0.20s
          Abnormal: If the PR segment is greater than 0.2 seconds, first degree AV block exists.
          Rhythm: Is the PR segment fixed and normal in every beat? If so, it's likely to be sinus rhythm


Qs? --- Normal: Is Q width normal? (<0.11sec. or <2.5ss)
       --- Abnormal: Q larger than 3ss => impulses come from ventricles

RR? --- RR interval- a normal QT is less than half the preceding RR interval. Otherwise, that's prolonged QT. 
      

5 - Height: ST & P?
Any ST elevation in any leads?
Is P upright in lead II? (if P is always upright in lead II, it's likely to be sinus rhythm)

6 - Pt's symptoms: 
Ex: 
SVT vs Vfib/V-tach:
- If pt is looking at u, it's probably SVT. But if pt is agonal, it's probably vfib
- If pt has SOB & CP but ur not sure if pt is SVT or VTach, treat pt first with cardiac cardioversion. However if pt is alert asymptomatic with just high BP, you still have some time to figure out which rhythm it is before treating the pt. 

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