ELG Flashcards
What’s the gold standard for ECG
12 lead ECG
What’s the blood flow
Deoxygenated blood comes from superior/ inferior vena cava, to right atrium through triscupid valve, to right ventricle, to pulmonary valve and pulmonary artery, then oxygenated blood comes into pulmonary vein, to left atrium, bicuspid valve to left ventricle, aortic valve then aorta
What is automaticity
Impulse conducting cells stimulate the heart without influence of nervous system
Define depolarization
Stimulation of polarized cells cause an influx of Na + into the inside of the cell
What is depolarization followed by
Repolarization
Define polarization
Rapid return of polarized position, electrical imbalance across the membrane is re-established
Normal p wave
No more than .10 seconds
Initiated by SA node and starts cycle
Depolarization of right and left atrium
PR segment
Normal is .12-.20 sec
QRS
.06-.10 sec
Depolarization of ventricles
Small box
0.04 sec
Big box
.20 sec
Calculate HR
of large boxes between R-R intervals and divide by 300
Ventricular tachycardia
Run of 3 or more PVC
Can cause 3rd degree AV block
What to do- synchronized cardioversion (stable) or defibrillation ( unstable)
V Fib
Life threatening , no cardiac output. Ventricles quiver
What do to- rapid defib and o2
Bradycardia
Caused by severe hypoxia, hypothermia and banal stimulation
What to do- atropine
Atrial flutter
Normal p wave is replaces with 2 or more saw tooth waves
QRS normal
Atrial rate of 250-350 bpm
Caused by rheumatic, coronary heart disease, pulmonary embolism stress renal failure and hypoxemia
Atrial fib
Absent P wave
Abnormal R-R interval
Causes blood to stagnate and form emboli
A- systole
Heart isn’t pumping
Non shockable rhythm
Must perform CPR , epinephrine and vasopressors
Pulse less electrical activity
The heart generate electrical signal by heart doesn’t generate pulse
Caused by pneumothorax, MI, drug overdose, of severe electrolyte
Treatment- resuscitation, life support and reversal of cause
Atrial premature complexes are due to
Premature activation of the atria
Premature ventricular contractions pvc
QRS is wide and bizarre
Heart is temporarily deprived of o2
Triggers depolarization
Premature ventricular complexes
Ectopic beats caused by early depolarization of the ventricles
Caused by anxiety, coffee and alcohol
