University:
West Coast University
Course:
NURS 110 | Introduction to Professional Nursing
Academic year:

2021
Views:

128

Pages:

1
Author:

jaxbrokenhart4z4x

Polymorphic Ventricular Tachycardia (Torsade de Pointes) Rate: 100-250 BPM PRI: P waves may be present if SA node is functional, however there is no relation to the QRS. It is unlikely that P waves will be visible, since this rhythm typically moves at a very fast rate, and the P waves will be buried in the QRS. QRS: Wide/Bizarre > .12 QT: Usually, < .40 seconds due to fast heart rate. Rhythm: Usually regular Source of pacer: Ventricular/Purkinje Fibers Characteristics: Polymorphic ventricular tachycardia (PVT) is a form of ventricular tachycardia in which there are multiple ventricular foci with the resultant QRS complexes varying in amplitude, axis and duration. The commonest cause of PVT is myocardial ischaemia. Torsades de pointes (TdP) is a specific form of polymorphic ventricular tachycardia occurring in the context of QT prolongation; it has a characteristic morphology in which the QRS complexes “twist” around the isoelectric line. For TdP to be diagnosed, the patient has to have evidence of both PVT and QT prolongation. Torsade de Points is essentially a polymorphic VT. It is characterized by a widening and narrowing of the QRS amplitude. The arrhythmia may be paroxysmal, which starts and stops suddenly and may suddenly deteriorate into VF. Bidirectional VT is another type of polymorphic VT, most commonly associated with digoxin toxicity. Causes: The cause of Torsades may be reversible. The most common causes are drugs that lengthen the QT interval such as antiarrhythmics (quinidine, procainamide and stalol). Other causes include myocardial ischemia, and hypokalemia, hypomagnesemia and hypocalcemia. Nursing Priorities: Unstable patients have signs or symptoms of insufficient oxygen delivery to vital organs as a result of the tachycardia. Such manifestations may include the following: Chest pain, Dyspnea, Hypotension, Altered level of consciousness Potential Treatments: Find and treat reversible causes. Overdrive pacing with the use of an external pacer or Isuprel may overdrive the ventricular rate and break the triggering mechanism of the arrhythmia. Magnesium sulfate may also be effective. Refer to your ACLS manual for detailed treatment algorithms. Polymorphic ventricular tachycardia with a pulse requires defibrillation not synchronized cardionversion.