Lab 3 Flashcards
each cardiac cycle requires _____ seconds
0.8 seconds
how does it compare to the interval between the first and second heart sounds?
the 1st and 2nd heart sound intervals and shorter than the 2nd and 3rd
rate of intensity of the sounds in the sitting position and in the supine position (laying on back)
more intense and faster while standing and slows while laying down
what event is responsible for the 1st heart sound
closure of tricupid and bicuspid valves
what event is responsible for the 2nd heart sound
closure of pulmonary and aortic semilunar valves
what is a heart murmur
extra heart sount
what causes a heart murmur
when the valves don’t close/open properly
pulse
produced in the arteries due to ventricular contraction
where is the easiest area to locate your pulse
at the radial artery of the wrist
tachycardia
refers to a rapid heart or pulse rate
bradycardia
indicates a slow heart rate or pulse
electrocardiogram
- definition
- consists of what
the graphic record of the electrical changes occurring during the cardiac cycle
-deflection waves
lead
the electrodes working in pairs
leads
- lead I
- lead II
- lead III
- right wrist and left wrist
- right wrist and left ankle
- left wrist and left ankle
how are all 3 leads similar
All show a QRS, show electro activity of the heart
how are the leads different
Lead II barely has T wave and height of peaks are different
point where Lub occurs
QRS complex
point where dub occurs
after T wave
calculate heart rate manually
of R peaks/10 sec = X beats /60 sec
P wave
- normal duration (sec)
- normal amplitude (m Volts)
- 0.06 - 0.11 sec
- <0.25
QRS complex
- normal duration (sec)
- normal amplitude (m Volts)
- < 0.12 sec
- 0.8 - 1.2
T wave
- normal duration (sec)
- normal amplitude (m Volts)
- 0.1 - 0.2 sec
- < 0.5
ST segment
- normal duration (sec)
- normal amplitude (m Volts)
- 0.12 sec
- N/A
PR segment
- normal duration (sec)
- normal amplitude (m Volts)
- 0.12 - 0.20 sec
- N/A
systolic pressure
pressure in arteries at the peak of ventricular ejection
diastolic pressure
reflects pressure during ventricular relaxation
how is systemic blood pressure commonly measured
with a sphygmomanometer
what does turbulent blood flow create
a sound that can be heard with a stethoscope
laminar
smooth blood flow
Prior to inflating cuff
- type of blood flow
- sound
- laminar
- no sound
Inflate cuff to 200 mmHg
- type of blood flow
- sound
- no blood flow
- no sound
decrease cuff pressure to ~120 mmHg
- type of blood flow
- sound
- turbulent
- knocking
decrease cuff pressure to ~80 mmHg
- type of blood flow
- sound
- mixed
- muffled sound (whooshing)
decrease cuff pressure below 80 mmHg
- type of blood flow
- sound
- laminar (smooth flow)
- no sound
how did blood pressure change during cold exposure?
it decreases
what is the function of the vasoconstriction resulting from the cold
it causes less blood flow
effects of nicotine
- HR
- BP
- Pulse pressure
- increases
- increases
- increases
