general cardiovascular Flashcards
Where is the heart situated?
2/3 left sided restrosternal in the mediastinum, tip pointing to the bottom left
behind: osophagus, holzknechtian space
front: sternum, erbs point
below: diaphragm
Constitution of the heart muscle?
from the inside to the surface:
endocard, myocard, epicard, liquid, pericard
Course of the coronary arteries?
right: ramus interventricularus posterior, sidebranch ramus marginalis
left: ramus circumflexus, ramus marginalis; ramus interventricularis anterior, sidebranch ramus diagonalis
What is between the left and right ventricle?
ventricle septum
When are the coronary arteries perfused?
during diastole due to backflow of windkessel function, cusps of the aortic valve close the coronary osteses during systole
What is preload/afterload?
pre: passive expansion of the ventricular muscle during the diastolic filling phase of the heart
after: due to the active contraction of the ventricle during the systolic ejection phase
Dependency of cardiac output?
co = hr * sv
Significance of the arterial/venous system?
art: carry mostly oxygen rich blood, lead away from the heart
ven: lead to the heart, carry mostly non oxygenated blood and have cusps to reduce backflow
Describe the physiological reflux of the blood in the veins?
muscle vein pump, due to muscle movement and parallel moving arteries the blood will be pushed to the heart, venous cusps prevent a backflow
What is hemoglobin?
oxygen transporting quaternary protein inside of an erytrocyte, oxygen is bound to the iron complex of the heme. hemoglobin is responsible for the bound oxygen transport
What binds the iron?
O2, CO, ions
What is the hematocrit?
gives information about the amount of solid compounds inside the blood
What are normal/surgery values for Hb and HKT
HB:
men: 13,5-17,5 g/dl
women: 12-16 g/dl
hlm: lower
HKT:
men: 42-50%
women: 37-45%
hlm: 20-30%
What is the ACT?
activated clotting time, measuring the coagulation activity of blood.
norm: 80-100s
hlm: 400-600s
Which coagulation reducing drugs are being used and how do they work?
heparin and low molecular heparin, increases the effect of AT3, inhibition of the formation of thrombin from prothrombin and fibrin from fibrinogen -> reduced aggregation of thrombocytes
mean time and doses of heparin?
T0.5: 90min
initial dose: 200-400 IE/kg
additional: 100-200 IE/kg
What is the counter part of heparin?
protamin/protamin sulfate, used when patient disconnected from hlm, 1ml eliminates 1000 IE
What are the known coagulation cascades?
primary hemolysis: stops bleeding, depending on thrombocytes and fibrin
secondary (plasma):
two paths that cross at factor Xa:
extrinsic: due to phosphate contact and tissue damage
intrinsic: inside the blood vessel system
Explain the Starling mechanism.
given that all other values are constant, the law states that an increase in preload results in an increased cardiac output.
What kind of artificial heart valves exist?
mech:
tilting disk
ball type
bi/tri leaflet
bio:
stented type
unstented type
(dis)advantages of said heart valves?
mech:
lifelong support
anticoagulation required
bio:
10-15 years
no anticoag.
non human tissue
Where is the centre for respiration and which parameters are most important?
partial pressure of carbon dioxide controls the rate of respiration inside the medulla oblongata
Describe the Seldinger technique.
used to safely access blood vessels:
1: punctured
2: guidewire advanced
3: trocar is withdrawn
4: sheath passed over wire to vessel
5: guidewire withdrawn
6: catheter can be placed on sheath
Name some of the bigger blood vessels.
aorta, branchio-cephalic arteries r/l, vcs/i, femoral veins r/l
What is a myocardial infarct?
due to coronary stenosis there is not enough blood supply for the myocard -> ischemia -> muscle cells die and replaced by scar tissue -> no action potential -> not enough contraction
What is angina pectoris?
A continuous chest pain (some times moves to the left shoulder and arm), it is caused by insufficient blood supply to the heart. Coronary artery disease is a common cause for angina pectoris
Which types of heart valve vitia do you know?
stenosis: not fully opening -> no good blood flow
insuff: no complete closing -> blood flows back
What are alcalosis and acidosis?
alc: abnormal increase of body blood pH
aci: abnormal decrease of body blood pH
Meaning of (para) sympathicus?
two counter parts of the nervous system that balance the control the involuntary movements like heart beat
What kind of heart/vessel deseases are known?
heart:
insufficiency
coronary desease
valve vitium
vessel: stenosis arterosclerosis arteriosclerosis thrombosis aneurysma
