Download Respiratory System II

Respiratory System II
•
The Mechanics of Respiration - Review
•
Pulmonary Volumes - Spirometry
•
Exchange of Gases - Pressure of Gases
•
Regulation of Respiration
•
Acid-Base Balance
Trachea
C-shaped cartilage rings
of trachea
Before
After swallow
During
swallow
Food
Esophagus
Cervical
vertebra
Respiratory cycle
Inspiration
Compliance
Expiration
Elastic recoil
Some videos
http://www.lungusa.org/site/pp.asp?c=dvLUK9O0E&b=40
743 animation of diaphragm movement
http://www.youtube.com/watch?v=xmceP5z6qsA&feature
=related shows lung (cows) inflation
http://library.med.utah.edu/WebPath/ORGAN.html#2 shows
organ system pathology
Lung Capacity
The amount of air that can be expelled
with the most forceful expiration
The amount of air The amount of air in
that remains in the
the deepest
lungs at all times
inhalation followed
by
the
most
forceful
The amount of air
expiration
in one normal in
and out
The amount of air
in and out in one
minute
The sum of tidal
volume, inspiratory
reserve and
expiratory reserve.
1. Tidal volume
2. Minute respiratory
volume
3. Inspiratory reserve
4. Expiratory reserve
5. Vital capacity
6. Residual air
The amount of air
that can be taken
in with the deepest
possible breath
Dead Space
•Anatomical Dead Space
- normal
- contains air left in the inactive parts of the respirator tract
•Physiological Dead Space
- not normal, not good
- nonfunctioning areas, may or may not contain air
Testing Respiratory volumes
http://www.intelitool.com/spirometry/Spirometry.h
tm
Partial Pressure of Gases
•
This law was discovered by John Dalton in 1801:
you have a certain amount of gas present (choose a
gas)
if you double the amount of (gas) present then it also
doubles the pressure - make sense!
If the gas you added was a different gas (choose a
different gas) then the pressure doubles, but each gas
contribute only 50% of the pressure
Therefore, each gas has a partial pressure
now for the numbers
First let’s review diffusion:
going from a greater
concentration to a
lesser concentration
The air you breath in (atmospheric air) is
approximately 21% oxygen, 0.04% carbon dioxide
(look at the chart on page 355 of your textbook)
When it gets to the lungs (alveolar sacs) it diffuses into
the blood (alveolar arterial capillaries) because of the
concentration difference
The air you breath out is approximately 16% oxygen,
4.5% carbon dioxide (reference page 354)
Regulation of Respiration
•
Nervous system and chemical work together
to cause the muscle movements of respiration
respiratory center is in the medulla and pons
of the brain
http://www.columbia.edu/cu/psychology/courses/1010/mangels/neuro/anatomy/str
ucture.html
The impulses from the brain tell the lungs to inflate, until baroreceptors send a
message back to the brain to stop the inflation. Then the muscles relax and we
exhale
Baroreceptors are nervous system
receptors sensitive to pressure
Chemical regulation
•
Chemical regulation of breathing refers to the pH of
blood and the oxygen/carbon dioxide levels in blood
Chemoreceptors detect changes of gases in the blood
and pH
If the chemoreceptors detect low oxygen, the
respiratory ratechemoreceptors
goes up
detect chemicals
If the chemoreceptors detect high carbon dioxide
levels, the respiratory rate goes up
Refer to page 360 and figure 15-10
Acid base balance
•
Taps and Drains
pH is a scale for measuring acid
and base/alkaline levels.
The blood’s pH must remain between 7.35 and 7.45
The body’s goal is a constant balance between
incoming/produced acids and bases (tap on) and
eliminated acids and bases (drain open).
Imbalances lead to acidosis (acid sink overflow) or
alkalosis (base sink overflow).
Balance can be restored by increasing elimination (faster
draining) and/or by decreasing flow (slowing down the
dripping tap).
Acidosis and alkalosis
Respiratory acidosis - respiration
decreases causing an increase of
carbon dioxide in body fluids
Respiratory alkalosis - respiration
increases causing a decrease of
carbon dioxide body fluids
Metabolic acidosis & alkalosis - When
the above situations are from reasons
other than the respiratory