Lab midterm #2 Flashcards
normal axis deviation
lead 1, lead 2, lead 3 all positive
right axis deviation
lead 1 negative
lead 2 positive
lead 3 positive
left axis deviation
lead 1 positive
lead 2 negative
lead 3 negative
heart rate determination
HR in bpm (beats per minute) = 1500/# of tiny beads
PR interval
the time interval from the beginning of the P wave (the onset of atrial depolarization) until the beginning of the QRS complex (the onset of ventricular depolarization) through the AV junction
normal PR interval range
0.12 sec to 0.2 sec
prolonged
> 0.2 sec, indicates heart block
abnormally short
<0.12 sec, indicates less blood flow and lower cardiac output
SA block
(characteristic and where to look)
look at lead II
absent p wave
first degree AV block
(characteristic and where to look)
look at lead II
long PR interval
second degree AV block (Mobitz I)
(characteristic and where to look)
look at lead II
increasing PR intervals, until QRS is dropped or missing
second degree AV block (Mobitz II)
(characteristic and where to look)
look at lead II
multiple p-waves
can be 2:1 ratio or 3:1 ratio
third degree AV block
(characteristic and where to look)
look at lead II and pattern along entire strip
no association
right bundle branch block “RBBB”
(characteristic and where to look)
look at lead V1 and/or V2 (right side leads)
R is left ventricle and R’ is right ventricle
two peaks, R and R’ where R’ is higher
left bundle branch block “LBBB”
(characteristic and where to look)
look at lead V5 and/or V6 (left side leads)
R is right ventricle and R’ is left ventricle
looks like a plateu
right atrial enlargement (RAE)
(characteristic and where to look)
look at lead II, III, and aVF (inferior leads)
tall p wave
left atrial enlargement (LAE)
(characteristic and where to look)
lead II, III, and avF (inferior leads)
lead I has a wide p wave
lead V1 has a biphasic p wave
right ventrical hypertrophy (RVH)
(characteristic and where to look)
look at leads V1 and V5 and V6
V1 and V2 are positive
V2 and V6 are negative
left ventricle hypertrophy (LVH)
(characteristic and where to look)
look at leads in V1 and V5 or V2 and V6
sum of S wave in V1 and R wave in V5 is greater than or equal to 35nm
PVC criteria
- no p wave
- wide QRS complex
- T wave usually points in the opposite direction of the QRS wave
Unifocal PVC
PVC looks the same in a given lead
Comes from the same source
Multifocal
PVC will look different in a given lead
Comes from different sources
Bigeminy
Every other beat is a PVC
Trigeminy
Every third beat is a PVC
Quadrigeminy
Every fourth beat is a PVC
Ventricular tachycardia (V tachycardia)
3 or more PVCs in a row
R on T PVC
R wave of PVC occurs on T wave of the preceding beat
Ventricular Fibrillation (V Fib)
Rapid, irregular electrical signals cause the heart’s ventricles to quiver uselessly instead of pumping blood
Sudden Cardiac Arrest
Sudden loss of heart activity due to an irregular heart rhythm
Sudden Cardiac Arrest symptoms
- collapse
- no pulse
- no breathing
- loss of consciousness