Abnormal CV Response (exam 3) Flashcards
What is cardiac output?
Q=SV*HR, amt of blood pumped through the body per minute
What is a normal cardiac output?
4-8 L/min
Normal HR values
60-100 bpm
Normal respiratory rates
12-20
Normal blood pressure
120/80
Normal SpO2
98-100 (age effect is minimal)
Effect of exercise on HR
HR goes up
What is a blunted response? Who gets it
HR goes up, not as much. DM or beta blockers
What happens to BP with exercise?
Goes up
What does it mean if your BP does not go up during exercise?
Cardiac Output is going down
If your highly trained, workload is not high enough
What happens toRR with exercise?
Goes up
What happens to SpO2 with exercise?
stays same
What is stroke volume?
Amt of blood ejected out of the heart each beat
What is the stroke volume dependent on?
Preload (venous return), Contractility, Afterload
What are some factors that influence heart rate?
Intrinsic rhythm and autonomic regulation
What is venous return? What effect will it have?
Amt of blood returned to heart from periphery. If you have less venous return, then you will have a lower End Diastolic Volume and lower cardiac output
What is the Frank-Sterling Relationship?
Length tension relationship btwn myocardium and strength of contraction?
What is afterload?
Amount of force required by heart to overcome pressure of aortic valve to send blood out into the system. Higher force needed, less blood can be pumped out
What are the 4 factors that cause an abnormal effect on the CV system?
Heart Rate, Rhythm, volume, pressure
What is resting HR in reference to?
In reference to baseline
What is chronotropic Incompetence?
Inability for heart rate to increase in response to increased activity and/or inability to achieve 85% of HR max
What is chronotropic Incompetence associated with?
Left Ventricle dysfunction, myocardial ischemia and increased mortality
What are some potential causes or associations of Chronotropic incompetence?
Older age Presence of CAD Smoking Exercise inteolerance LV dialation Ischemia SA or AV node dysfunction Issue with modulating autonomic tone
What does a delayed decrease in HR during 1st minute of recovery lead to?
increased mortality
What are some pathologies that will give you an abnormal HR response?
Medications Heart transplant Autonomic dysfunction Ischemia Mechanical support
What are the two types of arrhythmias?
Atrial and ventricular
Atrial/Ventricular arrythmias are not predictive of mortality or a diagnostic for CAD?
Atrial
What is a drop in systolic blood pressure associated with?
severe CAD and ischemic LV dysfunction. Can also identify those at risk for Ventricular fibrillation
What is the normal response to standing?
500-1000 mL pooling of blood in legs decrease venous return to heart decrease CO and BP decrease arterial barorecptor response and increased sympathetic activity increased venous return, PVR, CO, limits fall in BP</p>
What is orthostasis?
When going from sitting to standing, the SBP drops >20 mmHG and the DBP drops >10 mmHg. THis must happen within 3 minutes of standing or at least 60 degrees on a tilt table.
What are some confounding variables for orthostasis?
Food ingestion, time of day, state of hydration, ambient temperature, recent recumbency, postural reconditioning, hypertension, medications, gender, age
What are some medications that cause orthostasis?
Antidepressants Beta and alpha blockers ACE inhibitors Vasodilators/nitrates Calcium channel blockers Opiates
What are some causes of Orthostasis?
Decreased intravascular volume
Autonomic insufficency
alcohol consumption (impairs vasoconstriction)
aging
What does POTS stand for?
Postural Tachycardia Syndrome? Sustained HR increase of > 30 bpm w/in 10 minutes f standing or head-up tilt without orthostatic hypotension
Who is POTS more common in?
women
What are some symptoms of POTS?
lightheadedness, visual blurring
How do you treat orthostasis?
Medications (midodrine, florinef)
Diet (increased salt)
Compression (LE compression therapy: 40-60 mmHg, abdominal binder
