Garman- CV1: Intro CV Flashcards
Which part has largest volume distribution of blood in CV system?
Veins (64% or 2/3 or blood)
Where is the most resistance met in vascular system?
Small arteries and arterioles (47%)
Capillaries (27%)
How long does it take for blood to make complete circuit?
1 minutes (5L of blood/5L of minute)
Which organ take largest flow of blood at rest?
Liver and GI trat (Q=24%) and skeletal muscle (21%) Kidney (21%)
What is another name for the high-pressure system in CV system?
Supply function
What is another name for low-pressure system in CV circuit?
Reservoir function
Which area takes highest amount of oxygen consumption (VO2)?
Liver/GI tract (24%) Skeletal muscle (27%)
Why does the kidney take a lot of blood, but not utilize much oxygen consumption?
Kidney cleans blood but does not extract much oxygen from blood
How do we direct blood from one tissue to another?
Manipulate size of arterioles/small arteries
How much time spent in veins at rest?
38 seconds (most time)
How much time spent in capillaries at rest?
3 seconds
How much time spent in heart at rest?
4 seconds
How much time spent in large arteries at rest
4 seconds
How much time spent in small arteries at rest?
5 seconds
How much time spend in lungs at rest
5 seconds
How much blood do we typically pump in exercise?
25 L/minutes
How does flow through organs change during exercise?
Heart increases flow
GI decreases flow
Skeletal increases flow a lot
Renal decrease flow 50%
Where is base of heart?
Flattened superior portion
Where is apex of heart?
Inferior tip, directed downwar and to the left
What is the pericardium?
Double walled sac that covers heart
Formed from visceral pericardium and parietal pericardium
What is pericardial cavity?
Formed between visceral and parietal pericardium
What is endocardium
Areolar tissue and endothelium. Continuous with blood vessel
What makes up myocardium
Cardiac muscle cells
Connective tissues
What makes up parietal pericardium?
Dense fibrous layer
Areolar tissue
Mesothelium
What makes up epicardium (visceral pericardium)
mesothelium (simple squamous cell)
areaolar tissue
How does heart muscle contract? (motion)
Wraps in spiral shape
Pathway of blood flow through heart
Blood from systemic circuit –> venae vacae and coronary sinus–> RA–> RV via tricuspid–> pulmonary trunk via pulmonary valve–> pulmonary capillaries–> alveolar capillaries–> pulmonary veins–> LA –> LV via mitral valve–> Aorta via aortic valve–> blood to systemic circuit
Heart is a ___ pump
double (systemic and pulmonary circulation)
How to calculate CO?
HR x SV
What is referred to as systemic circulation?
Left heart–> aorta–>tissues
What is referred to as pulmonary circuilation?
Right heart–> pulmonary arteries–> lungs
What receives deoxygenated blood from tissues?
Right atrium
What delivers deoxygenated blood to lungs?
Right ventricle
What receives oxygenated blood from lungs?
Left atrium
What delivers oxygenated blood to tissues?
Left ventricle
What are the “great vessels”
Pulmonary trunk, right and left pulmonary arteries, right and left pulmonary veins, aorta, inferior and superior vena cava
What are the 2 AV valves?
Tricuspid, bicuspid valve
What are the 2 semilunar valves?
Pulmonic and aortic valves
What is structure of AV valves?
2-3 cusps
What is structure of semilunar valves?
3 Crescent shaped cups
What is normal pacemaker of heart?
SA node
What is route of conduction?
SA node–> internodal pathways–> AV node (delay)–> His-purkinje system–> ventricular myocardium
Why is there a delay in AV node?
To allow atria to contract
3 Facts for arteries?
- Delivery of blood under high pressure
- Thicker walled
- No valves
Types of arteries?
Elastic arteries, muscular arteries, arterioles
3 facts veins?
- Collection of blood under low pressure
- Thinner walled
- Valves to faciliatate blood return to heart
Types veins?
Large veins
Medium veins
Venules
What influences MAP?
Cardiac output, peripheral resistance
What influences pulse pressure?
Stroke volume, arterial compliance
What affects arterial pressure?
CO, SV, arterial compliance, peripheral resistance
Formula MAP?
sbp+ 2 dbp/3
Where is largest variation in pressure in circulation?
LV (120/0)
Range of pressure in aorta?
120/80
Range of pressure in large arterioles?
120-70ish
Rnage of pressure in RV?
25/0
Range of pressure in pulmonary arteries?
25/7
What is pressure?
Force/area
Expressed in mmHg or Torr (1 mmHg= 1 Torr)
Equation for pulse pressure?
Systolic-diastolic
What is equation for MAP?
SBP +2 DBP/3
What is flow?
Volume/time (mL/min or L/min)
Equation for CI?
CO/m2 ( m2= surface area)
Equation for stroke index (SI)
SV/m2
Equation for flow?
Q= (P1-P2)/R
Normal resting CO?
5L/MIN
Normal HR
70 BPM
Normal SV
70 mL/beat
What is resistance?
Impedance to flow
mmHg/mL/min
Equation for poiseuille’s law?
R= viscosity (nu)X L x 8/ pi*r^4
Why is greatest resistance in arterioles
Small radius of vessel
What is relationship between velocity of blood flow and cross-sectional area?
Inverse
Why is velocity so low in capillaries
Blood needs to be slowed for nutrient exchange
What does tubulent blood flow do to pressure gradient?
Increases pressure gradient required to produce flow
What is pulmonary cpaillary wedge pressure a appoximation of?
LV end-diastolic pressure
What does PCWP reflect?
PV, LA pressure, preload of LV
Which CO curve has the highest peak? High or low CO
Low Co. The lower the peak, the higher the CO because cold fluid is leaving the heart quicker, causing a quick decline in temperature.
What is equation for fick principle?
CO= O2 consumption/ (A-V)o2
What is gold standard of CO?
TEE
How do we measure CO in TEE?
Velocity*area
Which is less invasive, TEE or PA catheter?
TEE
What technique is used to determine blood velocity in TEE?
Doppler technique
