Originally Posted by INnurse
HI Everyone, I really need some help here figuring this out. Let's say a pt is in rapid afib and has a bundle branch block. How would this show up on the monitor, and how should this be treated? Would this be a wide complex tachycardia.. should it be treated as afib or vtach? I recently had this scenario. My 85 year old male pt had a history of afib. He also had copd, along with multiple other medical problems. When I came on shift his rate was 145-148. This was not new with him for this admission, with any activity his heart rate had been up to 160. His activity was changed from brp to cbr. He had an order for cardizem for sustained rate over 120. I immediately started the gtt ( had not been started by previous shift). The order was for 5mg/hr only -- cardiologist who ordered is very familiar with this pt and his hx. Slowly, his heart rate did come down to acceptable level. However, throughout the night with any activity on his part, even just sitting up in bed or coughing, his heart rate would go back up to 140-150. When his hr would elevate it kept coming up on the bedside monitor as pvc's and vtach. When his rate would slow you could clearly see the afib and a bbb. I got 2 stat ekg's on him on my shift and they did not show vtach or pvc's but rather ectopic atrial tachycardia. Any comments welcome. Thanks.
The appearance on the monitor would vary depending upon the lead(s) being monitored and the rate. There are many references which offer probabilities as to whether certain observed characteristics in certain leads suggest ectopy or abberrancy. And as you observed, at higher rates it may become difficult to appreciate atrial fibrillation since the complexes may appear regular.
This patient, however, was well known to the cardiologist as having chronic atrial fibrillation with a bundle branch block. And since the cardiologist wrote a standing order for the cardizem, he clearly anticipated the possibility of a rapid ventricular response during this hospitalization. And by knowing his patient, he was able to order what "works" best/safest to achieve adequate rate control (which would be the goal in this case).
There are cookbook answers/algorithms for treatment of wide QRS tachycardias of uncertain origin. But obviously it would be more efficient to know exactly what you are dealing with....patient Hx, EKG and expert consultation with a cardiologist are appropriate in that regard.
Without trying to be flip, if a-fib it should be treated as a-fib (possibly digoxin, cardizem, or commonly used amiodarone etc. depending on the patient). Likewise if v-tach then treat as v-tach (probably amiodarone).
Of course, I am assuming that the patient is tolerating the rate which in most cases they will below 150/min; a severely symptomatic tachycardia will require emergent cardioversion regardless of its origin.
Finally, I would be curious as to when this patient's rate first exceeded 120/min since at the time you assumed care his rate was 145-148 and no drip running. Rapid ventricular rates can appear quite suddenly. On the other hand if the patient was allowed to cruise in the 130s for a period of time without intervention, I would complete an occurence report. The gradual response to the cardizem gtt without a bolus would likely have been a non-issue had it been initiated when the patient was in the 120s as ordered.