Well, there is something called the Brugada criteria which is used to distinguish between regular monomorphic wide QRS complex tachycardias/SVT and ventricular tachycardia....Kind of boring, so here is what I learned from ACLS!
Wide QRS complexes include PVCs, monomorphic V tach, polymorphic V tach, torsades de pointes and V fib...SO you see why it is a good thing to know the significance of the PVCs that you are observing
Monomorphic V tach is the most common form of ventricular tachycardia. It is considered life-threatening, as you know, because it may lead to ventricular fibrillation. What causes it? Usually myocardial irritability and circuit reentry, usually precipitated by a PVC that occurred during the period of ventricular repolarization, a/k/a R-on-T .
Polymorphic v tach, well the complex itself is unstable, as it varies from the site of origin throughout the ventricle. By-the-by, Polymorphic Ventricular Tachycardia is associated with a much poorer prognosis than monomorphic
Torsades de pointes is also life-threatening; also a polymorphic ventricular tachycardia, and it CAN degenerate into ventricular fibrillation.
Treatment for all of the above: Amiodarone (for Torsades administer Magnesium) and if patient unstable, debfibrillation.
When you are talking about narrow complex tachycardia (QRS < 0.12 seconds) and wide complex tachycardias (QRS >/= 0.12 seconds) you've gotta identify the type of tachycardia and treat appropriately
If it is narrow complex and regular, attempt vagal maneuvers then adenosine. IF irregular narrow complex could it be a. fib or atrial flutter?? Use diltiazem (I would use that first instead of a beta adrenergic blocker especially if I don't know the patient's Hx like pulmonary disease...)
IF wide QRS and patient STABLE then assess if regular or irregular. If appears regular amiodarone and prepare for synchronized cardioversion. IF irregular would also suggest amiodarone and call for consult. If Torsades, Mag sulfate.
Hope this helps!
thank you athena.
I am talking about when "it appears" that someone had "say" a run of VT or is in actual stable VT. Some nurses are refering to it as "wide qrs tachycardia rather than just saying VT.. so my question is what is really the difference between a wide qrs or VT...i understand about pvc's and that but I am talking about a non sustained situation.
There is a difference...and please correct me if I'm wrong (because I am certainly no expert)...but there are some rhythms that can look like v-tach and not be v-tach. You really need a 12 lead of these kind of runs to look at the morphology of the QRS. There are some very technical aspects to evaluating these things...however...as nurses...the only thing that is really important is...are they going down now...or are they going down later. A "stable" wide QRS rhythm will become unstable at one point or another...as the heart just can't sustain a rate like that without some adverse effects.
Go here and look at the dysrhythmia monitoring. There is lots of stuff about qrs morphology and v tach vs svt with abberancy.
"Wide Complex Tachycardia" is an umbrella term when the exact nature of the arrythmia is difficult to ascertain. Monomorphic VT, SVT with abberrancy, SVT or atrial fib with preexisting bundle branch block, Ashman phenomenon, and others fall into this category.
Just like SVT is an umbrella term that other, more specific, arrythmias fall under.
As a monitor tech, I usually report and chart "WCT" unless I am able to definitively identify something as VT.