Test 2 Flashcards
Effect where the elastic recoil of the aorta helps to “dampen” or “smooth out” the pulsatile flow of blood out of the left ventricle of the heart
Windkessel Effect
The there layers of arteries
Tunica intima Tunica media Tunica externa (or adventitia)
Blood flow through arteries is affected by two major variables What are they?
pressure and resistance.
Q=∆P/R
the force with which blood is pushed against the walls of blood vessels
Blood Pressure
highest amount of pressure reached during ventricular ejection of blood
Systolic Pressure (SP)
minimum amount of pressure just before ventricular ejection begins
Diastolic Pressure (DP)
potential energy is then released by the RECOIL of the arterial wall, which propels the blood distally and provides the________This alteration of systolic and diastolic propulsion provides a more continuous (rather than pulsatile) flow to the peripheral tissues. This pressure-storing property of the aorta is sometimes called the ______ effect.
“diastolic runoff”
“Wind Kessel”
Auscultatoric measurement devices determine blood pressure by monitoring…
Korotkoff sounds
These measurements use an electronic pressure sensor with a numerical readout of blood pressure.
Oscillometric measurement device
Mean Arterial Pressure (MAP) =
2/3 DP + 1/3 SP
or
MAP = DP + 1/3 PP
the sum of all resistance in the vasculature
Total Peripheral Resistance (TPR) or Systemic Vascular Resistance (SVR)
There are 3 important sources of resistance within a single vessel:
- blood viscosity
- vessel length
- vessel diameter or radius
The relationship between resistance, viscosity, vessel length, and vessel radius is explained with
Poiseuille’s Law.
POLYCYTHEMIA
high hematocrit state
Another factor that is influences viscosity is the tendency of RBCs to aggregate into stacks called…
ROULEAUX
in blood flow Resistance=?
R = 8 V L / π r^4
Baroreceptors are neural receptors located in the…
CAROTID SINUS and AORTIC ARCH
Which cranial nerves carry signals from baroreceptors?
Cranial nerves IX (glossopharyngeal) and X (vagus)
What center of the brain processes signals from baroreceptors?
MEDULLARY CARDIOVASCULAR (or CARDIOREGULATORY) CENTER of the brainstem
Medullary Cardiovascular Center Functions
Makes decisions about what to do about hypertension or hypotension…..and then employs the services of the SNS and ParaNS to send those orders to various target tissues
Why would baroreceptors get used to high BP?
decreased sensitivity of the baroreceptors to increases in arterial pressure or an increase in the blood pressure set point of the brainstem centers.
A decrease in renal perfusion pressure (blood pressure) causes kidneys to secrete this enzyme
RENIN
Renin catalyzes the conversion of
ANGIOTENSINOGEN to ANGIOTENSIN I in the plasma
catalyzes the conversion of angiotensin I into ANGIOTENSIN II
ANGIOTENSIN CONVERTING ENZYME (ACE)
Hypovolemia, or volume contraction ( e.g., due to hemorrhage), is also a potent stimulus for…
ADH secretion
ADH has 2 effects that tend to increase blood pressure toward normal. What are they?
It increases water reabsorption via the kidneys activates V_2 Receptors
It is a potent vasoconstrictor that increases TPR by activating V_1 Receptors
The responses to an increase in blood volume include:
- increased secretion of ANP
* decreased secretion of ADH
This hormone is secreted by the atria in response to increased atrial pressure
ANP
Effects of ANP
• Causes relaxation of vascular smooth muscle, which results in
vasodilation and decreased TPR
• In the kidney, this vasodilation leads to increased Na+ and water excretion, thereby decreasing total body Na+ content, ECF volume and blood volume
Hypertensive cases are classified as secondary when?
Caused by a disorder or situation that increases TPR or CO, e .g.
The chronic elevation in blood pressure that occurs without any evidence of underlying disease
Primary (Essential) Hypertension
Commonly associated with hypertension and diabetes mellitus
Arteriosclerosis
Entire wall of the artery “outpouches” common in..
Circumferential or Fusiform Aneurysms
Common in the abdominal aorta (AAA = abdominal aortic aneurysm)
Only one portion of the arterial wall “outpouches”
Saccular or Berry Aneurysms
Most often observed in the small arteries of the brain, especially in the Circle of Willis
Saccular or Berry Aneurysms
Tunics of the arterial wall separate; blood collects in-between the tunics and are common in…
Dissecting Aneurysms
Common in the aortic arch
Fluid movement across clefts and fenestrations is driven by…
Starling forces
Pc ∏c etc…
collects lymph from most of the body regions
The thoracic duct
receives lymph from the right side of the head, neck, and trunk and from the right upper extremity. It empties into the right subclavian vein
The right lymphatic duct
Edema occurs when the volume of interstitial fluid exceeds the capacity of the lymphatics to return it to the circulation.
It can be caused by:
- excess filtration (typically reflected by ↑P
- decreased absorption (typically reflected by ↓π
- increased capillary permeability
- blocked lymphatics
When the external
intercostals contract, they do two things:
• elevate the ribs superolaterally (“bucket handle”) • move the sternum anteriorly (“pump handle”)
Upper Respiratory Structures
- nose
- pharynx
- larynx
Lower Respiratory Structures
- trachea
- bronchi
- bronchioles
- alveolar ducts & sacs
- alveoli
Causes bronchodilation
sympathetic nervous system via β2 receptors
causes bronchoconstriction
parasympathetic nervous system via muscarinic receptors
gas exchange occurs within the
alveoli
Right lung has ___ lobes, while the left lung has__ lobes.
3
2
These cells are thin and flat (simple squamous); constitute 90% of alveolar surface area
Type I alveolar cell (Type I pneumocyte)
These cells synthesize pulmonary surfactant
Type II alveloar cell (Type II pneumocyte)
clean off particles such as dust or microorganisms; frequently contain granules of exogenous material such as particulate carbon that they have picked up from respiratory surfaces (particularly in smokers)
Alveolar macrophage (dust cell)
protects tissues from neutrophil elastase
ALPHA-1-ANTITRYPSIN
The absence of alpha-1- antitrypsin results in
respiratory complications ( i.e., emphysema, COPD) and cirrhosis
Is a tool for the measurement of the breathing capacity of the lungs
Diagnostic spirometry
is a method of encouraging voluntary deep breathing by providing visual feedback about inspiratory volume.
Incentive spirometry
Incentive spirometry reduces the risk of
atelectasis (collapsed lung) and pulmonary consolidation.
Define Tidal Volume (TV)
amount of air that moves into and out of the (TV) airways with each inspiration and expiration during normal quiet breathing – usually around 500 ml
Define Minute Ventilation
Total volume of air taken in by the body during 1 minute
Minuet Ventilation=
TV x RR
Define Anatomical Dead Space
The portion of the tidal volume that remains in the nose, pharynx, larynx, trachea, bronchi, and terminal bronchioles – i.e. the air that does not participate in gas exchange
Define Alveolar Ventilation
Total volume of air that reaches the sites of gas exchange during 1 minute
Alveolar Ventilation+
AVe = (TV-ADS) x RR
Define Inspiratory Reserve Volume (IRV)
The amount of air you can inspire above your normal tidal volume
Define Expiratory Reserve Volume (ERV)
The amount of air you can expire above your normal tidal volume
Define Residual Volume (RV)
The amount of air that remains in the respiratory system after a forced expiration
Define Functional Residual Capacity (FRC)
The sum of the residual volume and expiratory reserve volume
Define Inspiratory Capacity (IC)
The sum of the tidal volume and IRV
Define Vital Capacity
The sum of tidal volume, IRV and ERV
Temporary increase in blood pressure when standing up
Orthostatic Hypertension
RAA system steps
Rennin, Angiotensinogen, Angiotensin 1, angiotensin 2» (Brain ADH and Kidney Aldosterone)
What is whiteout syndrome
BP increases when a doctor or someone tries to take your blood pressure.
What is Atherosclerosis?
Plaque buildup in arteries
What is Arteriosclerosis?
Hardening of the arteries. Via hypertrophy of muscular layer.
The most common cause of type 2 hypertension
renal failure
What is intermediate Clodication?
When light activity causes chest pain, muscle pain, and fatigue.
What is the circle of willis?
arteries in the base of the brain that get aneurysms some times.