Units of (a)   are volume divided by time such as liters/min

• Volume flow rate

• Volume of blood moving per unit of time

• Units of volume over time

(a)   is the study of blood moving through the circulatory system

(a)   indicates speed or swiftness of a fluid moving from one location to another

The units for (a)   are distance divided by time, such as cm/s

• Speed of blood from one point to another.

• Units of velocity. Distance over time

(a)   occurs when blood moves with variable velocity. Commonly appears in the arterial circulation

• Variable velocity along with  HEART CONTRACTION.

• Arterial

(a)   also occurs when blood moves in variable velocity. Blood accelarates and decelerates as a result of respiration. Appears in the venous circulation

• Variable velocity along with RESPIRATION

• Venous

Occurs when a fluid moves at a constant speed or velocity. Steady flow is present in the venous circulation

(a)  

• Constant speed

• Venous

• During brief absence of respiration

Is when flow streamlines are aligned and parallel.

(a)  

Is characterized by layers of blood that travel at individual speeds.

(a)  

Laminar flow patterns are commonly found in (a)   physiologic states

(a)   flow occurs when all the layers and wood cells travel at the SAME velocity

(a)   flow as a bullet shaped profile. Velocity is highest in the center of the lumen and gradually decreases to its minimum at the vessel wall

The (a)   predicts whether the flow is laminar or turbulent

• Reynolds number < 1500

(a)   flow is characterized by chaotic flow patters in many directions at at many speeds

• Swirling, eddy currents

• Seen with cardiovascular pathology

• Associated to stenosis (narrowing) of a vessel.

• Produces sound (murmur or bruit), vibration (thrill)

• Reynolds number > 2000

Re = Inertia / viscosity = (r V dV/dx) / (mu * d^2V/dx^2)

(a)  

Energy produced by the contraction of the heart during systole moves blood from one location to another.

(a)  

Blood moves from regions of higher energy to lower energy

(a)  

Heart, capillaries, arteries, venues, arterioles, veins

(a)  

• Object’s mass

• Moving speed

• Potential

• Stored

• Ability to do work

• MAJOR FORM for circulating blood

• Potential

• Stored

• Elevational

Is a form of stored or potential energy associated with any elevated object

(a)  

is the tendency to remain in the same state.

(a)  

Applied to the moving blood, is the tendency of the blood to resist changes in its velocity

(a)  

(a)   describes the thickness of a fluid

Measured in units of poise

(a)  

(a)   is determined by the hematocrit (% of RBCS)

More viscous fluid moving = (a)   energy loss.

(a)   occurs when flow energy is converted to heat as one object rubs against another

(a)   in the circulatory system occurs in: arterial system (pulsatile), venous system (Phasic), and stenotic areas

Velocity (a)   as the vessel narrows

Velocity (a)   as blood flows out of the stenosis and into a vessel segment of normal diameter

A (a)   is the narrowing in the lumen of a vessel

• Change of direction of flow

• Increased velocity at the narrowest section

• Post-stenotic turbulence

• Pressure gradient across stenosis

• Pulsatile flow converts to steady flow

• Relationship between velocity and pressure of a moving fluid.

• Principle of conservation of energy.

• The sum of kinetic energy and pressure energy remains constant.

• Kinetic energy of blood increases as it speeds up though the stenosis from A to B

• If kinetic energy increases, then pressure energy (a)   , so the sum of energy remains constant.

(a)   is about the behavior of a fluid – a gas or a liquid – as it flows through a pipe or tube. It states that when the pipe narrows or widens, the fluid pressure and speed vary.

High pressure areas = (a)   speeds

Lower pressure = (a)   speeds

(a)   = flow x resistance

f = pressure gradient / resistance

(a)  

(a)   flow is multifactorial and complex:

Heart contraction, elastic wall, blood composition, pulsatility, blood pressure

Describes the relationship between the current, voltage, and resistance in a circuit.

(a)  

Voltage = current x resistance

(a)  

Pressure gradient = flow x resistance

(a)  

If resistance is increased and voltage remains the same, the current will (a)  

If voltage is increased and resistance remains the same, the current will (a)  

Pressure (fluids) = (a)   (electricity)

Flow (fluids) = (a)   (electricity)

Resistance (arterioles) = (a)   (ohms)

These relationships represent:

(a)  

• (a)   are collapsible, contain low pressure, are partially filled and have low resistance.

• (a)   accommodate large volume of blood with small increase in pressure

Body Position

Respiratory Changes

Cardiac Contraction

Arterial Pressure

Blood Viscosity

(a)  

This image shows features of the (a)  

One phase

(a)  

Two phases

(a)  

3 phases

(a)  

4 phases

(a)  

External carotid arteires

Extremity arteries

Fasting mesenteric arteries

(a)  

Internal carotid arteries, hepatic arteries, renal arteries, testicular arteries

(a)  

Pressure related to the weight of blood pressing on a vessel measured at the height above or below the heart

(a)  

(a)   reported in units of mmHg, same as blood pressure

When a person is (a)   , all parts of the body are at the same level as the heart and the hydrostatic pressure is zero everywhere

During (a)   the chest cavity expands creating negative thoracic pressure that increases venous return to the heart

During (a)   the diaphragm also presses the abdomen which increases abdominal pressure and decreases venous flow in the legs

During expiration, the diaphragm moves upward. This increased thoracic pressure (a)   venous return to the heart

Venous flow from the head, arms, and vena cava all (a)   during expiration

During expiration, decreased abdominal pressure (a)   venous blood flow in the legs

Thoracic pressure decreases

Abdominal pressure increases

Venous return to the heart increases

Venous flow in legs decreases

(a)  

Thoracic pressure increases

Abdominal pressure decreases

Venous return to the heart decreases

Venous flow in legs increases

(a)  

Volume of blood ejected each minute during ventricular contractions

(a)  

Amount of blood ejected during ventricular systole

(a)  

Percentage of blood pumped out of the LV during systole

(a)  

The cardiac output is corrected for differences in body size

(a)