Exam 2: Tisdale Flashcards
(121 cards)
What does a normal ECG look like? What are the characteristics?
- there is a p wave before every QRS complex
- there is a QRS complex after every p wave
- the QRS heights are equal
- HR btwn 60-100 bpm
How can we determine what the HR is on an ecg?
- can start with a complex on a box and count down from 300,150,100,75,60
- can also count the amount of peaks and multiply by 10
- can also count individual boxes inside
what is a normal ECG measurement for a PR interval?
0.12-0.20
what is a normal ECG measurement for a QRS interval?
0.08-0.12
what is a normal ECG measurement for a QT interval?
0.38-0.46
what is a normal ECG measurement for a QTc interval for men?
0.36-0.45
what is a normal ECG measurement for a QTc interval for women?
0.36-0.46
what is classified as torsades de pointes on an ECG? What is it?
- it is a life threatening condition that can lead to sudden cardiac death
- When the QTc interval is 500 ms, there is
increased risk of the drug-induced arrhythmia known as torsades de pointes
what drug classes can cause Torsades?
- antiarrythmics
- antidepressants
- antimicrobials (macrolides, fluoroquinolones)
- antipsychs
- opiods
- anticancer
what drugs cause torsades for each class?
- antiarrythmics –> amiodarone, flecanide, ibutilide, dofetilide, sotolol, dronedarone, prcainamide
- antidepressants –> citalopram, escitalopram, clomipramine, desipramine, lithium, mirtazapine, venlafaxine
- antimicrobials (macrolides (azithromycin, clarithromycin, erythromycin) fluoroquinolones (levofloxacin, ciprofloxacin, moxifloxacin)
- antipsychs –> Chlorpromazine, haloperidol, pimozide, thioridazine, aripiprazole, clozapine, iloperidone, olanzapine, paloperidone, quetiapine, risperidone, sertindole, ziprasidone
- opioids –> methadone
- anticancer –> Arsenic trioxide, eribulin, vandetanib (and most drugs ending in “nib”)
What are some superventricular arryhtmias?
sinus bradycardia, superventricular tachycardia, sinus tachycardia, afib, AV block
what are some ventricular arrythmias?
PVCs, VT, Vfib
What are the characteristics for bradycardia?
- HR < 60
- impulse originating in SA node
what is the mechanism of sinus bradycardia?
decreased automaticity in the SA node
what are some risk factors/ etiologies of how sinus bradycardia occurs?
- MI/Ischemia
- abnormal sns/psns tone
- electrolyte imbalances (increased k and mg)
- drugs (dig, bbs, ccbs, amio, droned, ivabradine)
- no reason (idiopathic)
what are symtpoms of sinus bradycardia?
hypotension, dizzy, syncope (passing out)
when do we treat sinus bradycardia and how do we treat it?
- only treat if symptomatic
- atropine 0.5-1mg q3-5min max 3mg
- can give other things (epi, dopa, ect. if not responsive)
what are some AEs of atropine?
tachycardia, blurred vision, dry mouth, urinary retention, mydriasis
what do you give patients for sinus bradycardia after a spinal cord injury or heart transplant?
aminophylline or theophylline
what is the LT treatment for sinus bradycardia?
pacemaker
what are the features of afib on an ecg?
- chaotic and disorganized (no atrial depolarizations)
- 120-180 bpm
- irregularly irregular rhythm
- no p waves
what are the stages of afib?
1,2,3,4
what is stage 1 afib?
there are modifiable and nonmodifiable risk factors associated with HF
what is stage 2 HF?
this is pre-afib
- there is evidence of structural or electrical findings that further lead to afib or enhance risk such as atrial flutter, enlargements, or premature beats