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Flashcards in dysrhythmias Deck (74)
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61

PVCs on EKG?

- rate: variable
- P wave: obscured by QRS with PVC
- QRS: wide 0.12, morphology is bizarre: the impulse originates below the branching portion of the bundle of his
- can have multifocal PVCs, R on T phenomenon (could be start of Torsades)
- full compensatory pause is characteristic
rhythm: looks irregular due to premature beat
- PVCs may occur in singles, couplets, or triplets, or bigeminy, trigeminy, or quadrigeminy

62

Tx for PVCs?

- tx may be reqd if they are:
assoc with acute MI
occur as couplets, bigeminy, or trigeminy continuously
- are multifocal
- are frequent (more than 6 PVCs per minute) and are assoc with hemodynamic instability
- lidocaine: class 1B antiarrhymic
- procainamide (pronestyl): clas 1A
- amiodarone (cordorone): class 3
- replace magnesium, K+ if appropriate

63

V tach?

- triggers of VT include ischemia and electrolyte abnormalities
- hypokalemia: most impt arrhythmia trigger clinically followed by hypomagnesemia
- hyperkalemia also may predispose to VT and VF, particularly in pts with structural heart disease

64

Causes of Vtach?

- MI: irritable ventricle
- Congenital heart defects
- dilated cardiomyopathy
- hypertrophic cardiomyopathy

65

What does V tach look like on EKG?

- absent P waves
- QRS greater than 0.12 because it arises from the ventricle
- regular rate and characteristic morphology
- classified as sustained: greater than 30 seconds or non sustained: less than 30 sec (NSVT)
- sustained will usually cause hemodynamic instability
- considered life threatening rhythm as it can degenerate to v fib

66

Tx for V tach?

- can have a pulse or be pulseless:
pulse:
cardioversion, antiarrhythmics to prevent recurrence: amiodarone
pulseless: considered the same as VF: defibrillation, antiarrhythmics to prevent recurrence: amiodarone, refractory cases are tx with ablation

67

Torsades de Pointes?

- means twisting about the points, usually paroxysmal
- hallmark of this is the upward and downward deflection of QRS complexes around the baseline
- caused by:
drugs which lengthen the QT interval
electrolyte imbalances, particularly hypokalemia and hypomagnesemia
MI

68

Tx of Torsades?

- synch cardioversion is indicated
- IV magnesium
- IV K to correct electrolyte imbalance
- overdrive pacing

69

V fib? Tx?

- sudden cardiac death
- dysrhymia results in absence of cardiac output
- almost always occurs with serious heart disease, especially acute MI
- course of tx:
immed defibrillation and ACLS protocols
ID and tx of underlying cause
consider ICD

70

Idioventricular rhythm? causes?

-absent P wave, widened QRS, greater than 0.12 s
- also called dying heart rhythm
- pacemaker will most likeyl be needed to re-establish a normal heart rate

causes:
- MI or infarction
- pacemaker failure
- metabolic imbalance

71

Tx of idioventricular rhythm?

- improve CO and est normal rhythm and rate
- options are:
atropine and pacing
- caution: suppressing the ventricular rhythm is CI b/c that rhythm protects the heart from complete standstill

72

What is asystole?

- presence of acute MI an CAD: almost always fatal
- complete cessation of any electrical or mechanical activity
- interventions include: CPR, 100% O2, IV, intubation, transcutaneous pacing, epi IV push q 3-5 min, atropine

73

What is pulseless electrical activity? (PEA)

- there is electrical activity, but no mechanical response
- what is seen on EKG is electrical activity appearing as normal sinus rhythm
- there will be NO pulse
- look for underlying causes - 6 Hs and 6 Ts:
hypoxia, hypovolemia, hypoglycemia, H ion (acidosis), hypothermia, hypo/hyperkalemia
toxins, tamponade, trauma, tension pneumothorax, thrombosis - cardiac, thrombosis - pulmonary

74

Tx for PEA?

- correct underlying cause
- epi: 1:10,000
- atropine
- CPR