ARRHYTHMIAS An arrhythmia is a disruption in the normal events of the cardiac cycle. It may take a variety of forms. SINUS TACHYCARDIA A. General information A heart rate of over 100 beats/minutes, originating in the SA node. May be caused by fever, apprehension, physical activity, anemia, hyperthyroidism, drugs (epinephrine, theophylline), myocardial ischemia, caffeine. Assessment findings Rate: 100-160 beats/minute Rhythm: regular P wave: precedes each QRS complex with normal contour P-R interval: normal (0.08 second) …showed first 75 words of 459 total…

…showed last 75 words of 459 total…ventricles Caused by acute MI, CAD, digitalis intoxication, hypokalemia B. Assessment findings 1. Rate Atrial: 60-100 beats/minute Ventricular: varies between 110-250 beats/minute 2. Rhythm: atrial and ventricular irregular P wave: often lost in QRS complex P-R interval: usually not measurable 5. QRS complex: greater than 0.12 second, wide C. Treatment IV push of lidocaine (50-100mg), then IV drip of lidocainamide 1-4mg/minute Procainamide via IV infusion of 2-6 mg/minute Direct-current cardioversion Bretylium, propranolol(inderal)