This document discusses hemodynamics and the physical laws governing blood flow. It defines key terms like stroke volume, cardiac output, and blood pressure. Factors that influence blood pressure include cardiac output, systemic vascular resistance, preload, contractility, and afterload. Mean arterial pressure is also discussed as an important indicator of perfusion to vital organs.

1. HAEMODYNAMICS
Dynamics of blood flow through
cardiovascular system.
Thus hemodynamics explains the
physical laws that govern the flow
of blood in the blood vessels.

2. Blood flow
Stroke Volume (SV): The amount of blood
pumped by the heart per cardiac cycle.
systole.
QUICK DEFINITIONS
Cardiac Output (CO): The volume of blood pumped by the heart in one minute.

3. REYNOLD’S NUMBER

4. REYNOLD’S NUMBER
•
RE=.v.d/

5. OHM’S LAW IN HEMODYNAMICS

6. Blood Pressure
•Measured in millimeters of mercury
(or kPa)
Blood flow: ↑ Pressure ↓ Pressure

7. FACTORS AFFECTING BLOOD
PRESSURE
• BP = CO x SVR
HR x SV
PRELOAD
CONTRACTILITY
AFTERLOAD
PRELOAD
• VOLUME RETURNING TO THE HEART WAITING
TO BE EJECTED OUT OF IT.
CONTRATILITY
• FORCE OF CONTRACTION
AFTERLOAD
RESISTANCE THE HEART MUST PUSH AGAINST

8. Pressure
•

9. Mean arterial pressure(MAP
It is average pressure in a
patient's arteries during one cardiac
cycle. It is considered a better
indicator of perfusion to vital organs.
MAP = [ (2 x diastolic)
+ systolic] / 3

10. MAPMAP is influenced byis influenced by
• Cardiac output
• Resistance in arteries
MAP CO x Rarterioles

11. POISEUILLE’S LAW