Reading 2: 83-99 Flashcards
What is experiment 2-1?
ECG and peripheral circulation
What do you do in the ECG n peripheral circulation exp?
Record single lead ECG and pulse wave in finger simultaneously
What is the purpose of exp 2-1
- Measure and correlate the ECG and the pulse in a resting individual
- Demonstrate time delay that occurs btwn electrical events in heart and mechanical events in circulatory system
What is the device used to measure pulses of blood?
PT-104 plethysmograph
What are the steps in the Exp 2-1: the ECG and peripheral circulation?
- Set up ECG Cable and Pulse Transducer into iWorx
- Remove all jewelry on subject’s wrists, ankles or clavicle
- Clean area with no hair on wrists and ankles or clavicle and abdomen with alcohol
- Attach red lead to left wrist/clavicle. Attach black lead to right wrist/clavicle. Attach green lead to right leg/abdomen
- Place plethysmograph on volar surface (fingerprints) of distal segment of middle finger/thumb. Wrap velcro around end of finger to attach unit.
- Subject needs to sit quietly with hands in lap
- Turn on IXTA
- Open Labscribe -> click Settings -> Human Heart -> ECG-Circulation
- RECORD
- AUTOSCALE
- Type in subjects name Resting ECG/Pulse in MARK box
- STOP
- Save file as Grp#DayTimeLab2Ex1
- Find section of data with 10 exemplary ECG/pulse cycles in succession
What is the beat period and how to find it? Units?
- time interval btwn 2 adjacent R waves
- place one cursor on peak of one R wave and 2nd cursor on peak of adjacent R wave. Value for T2-T1 on ECG channel is the beat period
- units: seconds/beat
What is the R-R interval and how to find it?
- Time interval btwn peak of R wave and peak of pulse wave that follows the R wave.
- one cursor on peak of R wave n second cursor on peak of pulse wave to its right. Value of T2-T1 is this interval
What is the eqn to calculate HR using the beat period?
HR (bpm) = (60 seconds/minute) / (# seconds/beat)
What is exp 2-2?
Exercise, ECG, and peripheral circulation
The arterial system fxns as a ____ resevoir
pressure
What does signals from the autonomic NS do
Control tone of smooth muscle sphincters around arterioles… thus controlling distribution of blood flow to various organs
How is the distribution of BF influenced by local conditions
e.g. if cells require arterial blood, due to decline in pH or O2 lvls or inc CO2, smooth muscle sphincters open to let BF into those capillary beds
How does BF change w/exercise compared to rest
- flow to gut dec w/exercise
- flow to working skeletal muscles inc w/exercise
- inc CO -> inc amount of BF around circulatory system by several fold
What is the purpose of Exp 2: The ECG and Pulse After Leg exercises?
To measure n correlate ECG and pulse immediately after exercise using leg muscles
Steps of Exp 2?
- Same setup as in Exercise
- SETTINGS -> HUMAN HEART -> EXERCISE-ECG-CIRCULATION
- Disconnect snap leads n pulse plethysmograph from subject
- Subject exercise ~3 min at 70%max (150bpm) thru biking or treadmill or rowing
- After 3 mins have subject relax next to recording equipment
- Reconnect cables/leads n pulse plethysmograph
- RECORD -> AUTOSCALE ALL -> type ECG/Pulse-recovery into mark box
- Record for 2 mins, marking every 30 mins
- Stop and save
How to measure R wave amplitude
- one cursor on Q wave that precedes R wave and 2nd cursor on peak of R wave. Value for V2-V1 on ECG channel is amplitude
How to measure P-R interval
- one cursor on p wave 2nd cursor on beginning of QRS complex . Value for T2-T1 on ECG channel is P-R interval
How to measure Q-T interval
one cursor at beginning of QRS complex and 2nd at end of T wave. Value for T2-T1 on ECG channel is Q-T interval
How to measure T-P interval
One cursor at end of T wave n 2nd at beginning of P wave. Value of T2-T1 on ECG is T-P interval
What is and how to measure R-Pulse interval
- time interval btwn peak of R wave and peak of pulse wave that follows R wave
- one cursor on peak of R wave and 2nd on peak of pulse to its right. Value for T2-T1 on any channel is this interval
How to measure pulse wave amplitude
one cursor on baseline that precedes the pulse wave n 2nd cursor on peak of pulse wave. Value for V1-V2 on pulse channel is amplitude.
How does ability of stress influence risk of coronary heart disease
People who r unable to cope w/stressful events run 7x higher risk to suffer from CHD
How do those who can’t handle stress act during stressful situations
impatient, aggressive, dissatisfied, irritable
What is HRV (heart rate variability) and used for?
analysis of variability of R-R interval in ECG indicates imbalance btwn sympathetic n vagal influences on heart
- comparison of sympathetic and vagal activity used as measure of stress
