ACLS review: Wide Complex Tachycardia (WCT) Review Questions Part 4

31.  What are two critical determinations that must be assessed in the management of symptomatic tachycardia?

32. What is the difference in the way symptomatic monomorphic VT and polymorphic VT is treated?

33.  What is the difference between synchronized cardioversion and defibrillation?

34.  What two tachycardic rhythms will not usually respond to synchronized cardioversion?

35. What are three potential problems associated with synchronized cardioversion?

36.  What are three examples of wide complex tachycardia?

37.  In what circumstances would you consider changing your initial dose of Adenosine?

38.  What are two initial interventions in the treatment of wide complex tachycardias?

39.  After delivering a synchronized shock to a patient you notice that the patient’s heart rhythm changes to VF.  What would you do?

40.  What is the cardinal rule for evaluating wide complex tachycardia?

Answers

31.  What are two critical determinations that must be assessed in the management of symptomatic tachycardia?

Determine if the patient have a pulse

Assess for signs and symptoms of hemodynamic instability

32. What is the difference in the way symptomatic monomorphic VT and polymorphic VT is treated?

Monomorphic VT is treated with synchronized cardioversion with an initial shock of 100J.   Polymorphic VT is treated with an unsynchronized shock at 200J.  For both, if there is no response to the first shock, then increase the dose in a step wise fashion. 

33.  What is the difference between synchronized cardioversion and defibrillation?

With defibrillation an unsynchronized shock is delivered randomly anywhere within the cardiac cycle. 

These shocks use a higher energy level beginning at 200J

The shock is delivered as soon as the operator pushes the shock button on the defibrillator

Synchronized cardioversion uses a sensor to mark the R wave and delivers the shock on the QRS complex. 

Synchronized cardioversion uses lower energy levels than defibrillation.

During synchronized cardioversion there is a slight delay in delivering the shock after the operator pushes the shock button.  This allows the machine to synchronize with the peak R waves of the QRS complex.

34.  What two tachycardic rhythms will not usually respond to synchronized cardioversion?

Junctional tachycardia and multifocal atrial tachycardia will not usually respond to synchronized cardioversion because these rhythms arise from an automatic focus within the myocardium that is rapidly depolarizing.

35. What are three potential problems associated with synchronized cardioversion?

If the R waves are low in amplitude or the rhythm irregular, the monitor may not be able to identify and synchronize with the R wave peaks

Synchronization can take extra time to complete as the operator is required to apply both the adhesive pads and the monitor electrodes.

36.  What are three examples of wide complex tachycardia?

Monomorphic VT

Polymorphic VT

SVT with aberrancy

37.  In what circumstances would you consider changing your initial dose of Adenosine?

The initial dose of Adenosine should be reduced to 3mg in patients taking dipyrimadole or carbamazepine.  Larger initial doses may be required for patients with higher blood levels of caffeine, theophylline, or theobromide. 

38.  What are two initial interventions in the treatment of wide complex tachycardias?

Vagal maneuvers

Adenosine

39.  After delivering a synchronized shock to a patient you notice that the patient’s heart rhythm changes to VF.  What would you do?

If the patient develops VF then deliver an unsynchronized high energy shock at 200 J and follow the pulseless VF/VT algorithm.

40.  What is the cardinal rule for evaluating wide complex tachycardia?

Rule No 1:  Wide complex tachycardia is VT until proven otherwise

Rule No 2:  Always remember rule No 1



Reviewed 2/28/16