Blood Vessels
What are the three layers of blood vessels?
What is adventitia, media and intima.
Explain why nitroglycerin works for angina pain but not MI pain.
What is the pain med that is given for MI pain?
Angina is caused by decreased blood flow through coronary arteries. Nitroglycerin causes the arteries to dilate. Coronary arteries dilation increases blood flow to myocardium (or cardiac muscle) and relieves angina pain. In MI the pain is caused by a blockage in the coronary artery and dilating the vessel will not relieve the pain.
Why are arterioles called resistance vessels?
They are composed primarily of smooth muscle that constricts and relaxes and is responsible for blood pressure.
Name structural differences between veins and arteries
1) veins have valves, areteries don't have valves 2) veins have 0 pressure; arteries are responsible for BP 3) veins are capacitance vessels (store most of the blood in body) and arteries are conductance vessels (have a thick/tough/elastic structure that withstands pressure of pumping heart) 4) veins have a thinner tunica media and arteries have a thicker tunica media
What lab levels are important to diagnosing MI?
myoglobin, CK-MB, troponin.
What causes varicose veins?
Defective valves in the veins
List mechanisms to help improve venous blood return back to the heart and prevent DVT.
What is the longest vein in the body that is most common used in CABG surgery?
What is great saphenous
These blood vessels have very thin walls allowing only one RBC through at a time
What are capillaries (aka exchange vessels)
Explain the primary effect of the medications epinephrine and hydralazine on the circulatory system.
Epinephrine causes vasoconstriction, which increases BP. It also causes bronchodilation which helps open the airways.
Hydralazine causes vasodilation which lowers systemic vascular resistance thereby reducing BP. Watch for hypotension and reflex tachycardia and warn patients not to stop taking suddenly.
Where is the radial vein located?
lateral aspect of the forearms bilaterally (runs near the radial artery where radial pulse is taken)
Decreased blood flow through the coronary arteries is most likely to cause what condition?
angina pectoris
Why are intravenous catheters are inserted into veins and not arteries?
veins have no pressure, less risk of hemorrhage.
Bonus: Explain the difference between a central line and a peripheral line.
What is the largest artery from which all other arteries brach off? What is the largest vein that all other veins flow into?
When a person is tachycardic what is the effect on the coronary circulation?
Decreased ability of coronary arteries to fill with blood because diastole phase of cardiac cycle is shortened.
Coronary blood flow is greatest when the heart is at rest.
What mechanisms cause blood to move from the veins toward the heart?
1) milking action of skeletal muscles 2) valves in veins 3) thoracic pressure changes