Page 110 - Critical Care Notes

4223_Tab02_045-106 29/08/14 10:00 AM Page 104

CV ■ ■ ■ PR interval: Becomes progressively longer until a QRS is dropped. ■ ■ drug induced: beta blockers, calcium channel blockers). Almost always temporary. If bradycardia → ↓ X Blocked beat

QRS: Normal.
Rhythm: Irregular.

P wave: Present until one P wave is blocked with no resultant QRS.

Management: Correct the underlying cause; atropine, temporary pacemaker; discontinue digoxin.

CO. Resolves when underlying condition corrected (MI, CAD,
104 Second-Degree AV Block—Mobitz I or Wenckebach Phenomenon