Lab 8 Flashcards
What can be used to measure more sensitive measurements to changes in cardirespiratory function
Cardiac and hemodynamic (blood pressure) assessments
What are 4 common measurements for gradex exercise test (GXT) assessments
Cardiac-electric condudction through 12-lead ECGs, ratings of percieved exertion (RPE), oxygen consumption, and blood pressure
What percent of Americans have high blood pressure
~1/3
Why can high blood pressure have deadly consequences
Due to added pressure within vasculature and on organs like the heart, brain, and kidneys
What is pulse pressure
The difference between diastolic and systolic pressures (sBP-dBP)
Why do blood pressures rise steadily with age
Due to arterial stiffness and plaque buildup
What is the breakdown of blood pressure categories
Normal: <120 / <80
Elevated: 120-129 / <80
Hypertension I: 130-139 / 80-89
Hypertension II: 140+ / 90+
Hypertension Crisis: 180+ / 120+
What does MAP determine
The rate of blood flow through vasculature
What is the equation for MAP
MAP = dBP + 1/3PP
or
MAP = dBP + 1/3 (sBP - dBP)
or
MAP = Q * TPR
Why do MAP calculations lose accuracy during exercise compared to at rest
Because the heart is in diastole for about 2/3 of the time during rest, but contracting (in systole) for longer when exercising
Why does blood pressure mainly rise during exercise
Due to the increase in cardiac output which increases systolic pressure without really changing diastolic pressure
What effect does aerobic exercise training have on BP
It decreases resting and submaximal BP by decreasing HR and vascular tone (TPR)
How does BP change at maximal exercise
Diastolic pressure may change while systolic and MAP don’t really change
What are 6 reasons to perform a GXT
Evaluate cardiorespiratory fitness in healthy and diseased populations, extend medical history and physical, evaluating exertional discomfort, evaluating presense of hidden coronary artery disease, stratifying risk in pts with known CVD, and prescribing exercise
What are subjects separated into groups based on for GXTs
Age, known disease, and risk factors
How does risk factor play into GXT exams
Low risk don’t need a medical exam or physician, moderate risk should get a medical exam first, and high risk should have both a medical exam first and have a physician present
What is the procedure for GXT exams
Risk screening, record resting HR and BP, start test at given work rate, stop at predetermined point, point of volitional exhaustion, or when chest pain or breathlessness occur
What are some general signs for stopping a GXT exam
1) Onset of angia/angia-like symptoms
2) Drop in sBP >10mmHg despite work load increase
3) Exsessive rise in BP (sBP > 250, dBP >115)
4) Shortness of breath, wheezing, or claudication
5) Signs of poor perfusion (light headed, confused, cyanotic, etc.)
6) Failure of HR to increase with increased intensity
7) Noticeable change in heart rhythm
8) Subject requests to stop
9) Physical or verbal manifestations of severe fatigue
10) Failure of testing equipment
When do many cardiovascular or physiological abnormalities present
When the body is stressed
What does an electrocardiogram (ECG) indicate
The hearts ability to function normally under increased myocardial oxygen demand
What is the most common sign of myocardial ischemia during a GXT
ST segment depression
What are the 5 characteristics of a normal/good prognosis during a GXT
1) Achieve > 80% predicted HRR
2) SBP increases 5-10 mmHg/MET
3) HR recovery = 12 bpm decrease in HR in 1 min
4) 3-min post-exercise sBP = <90% max sBP
5) Normal cardiac rhythms
What are the 5 characteristics of a abnormal/poor prognosis during a GXT
1) Achieve < 80% predicted HRR
2) Slow increase or sudden decrease in sBP
3) sBP >250 or increases >140 from rest
4) dBP increases >10 mmHg
5) Dysrhythmias, ST elevations/depressions
What speed will subjects use on the treadmill for GXT in lab 8
One that ellicits 70% HR max
