Case Study One ANS: Sue had a cold, which has progressively gotten worse. She is now coughing up
yellow to brown colored mucus and has a fever of 103 degrees. She is finding it difficult to breathe. She
goes to her doctor who gives her a full exam and orders blood work and a chest x-ray.
Lab results:
Elevated blood cell count
Arterial blood pO2 - 70mmHg (normal values = 75-100 mmHg)
Arterial blood pCO2- 48 mmHg (normal range = 35-45 mmHg)
Sputum sample shows the presence of Streptococci bacteria.
X-ray shows fluid build up in the one lung
Doctor diagnoses her with bacterial pneumonia and prescribes antibiotics and albuterol (a bronchial
dilator - beta2 adrenergic agonist).
Pneumonia is a lung infection caused by viruses or bacteria. The infection and inflammation causes
excessive secretions that interferes with normal gas exchange between the lung tissue and the blood.
Functions of Respiratory System ANS: Oxygen/carbon dioxide exchange
Acid/base balance
Route for water loss and heat elimination
Enhances venous return (cardiac output and BP)
Enables speech, hiccups, cooling food, blowing up balloons, laughing
Pulmonary Ventilation ANS: Breathing; air in and out
,External Respiration ANS: Gas exchange between lungs and blood
Tidal Volume ANS: The volume of gas inspired or expired in an unforced respiratory cycle
Total Lung Capacity ANS: The total amount of gas in the lungs after a maximum expiration
Vital Capacity ANS: The maximum amount of gas that can be expired after a maximum inspiration
Lung Compliance ANS: How much effort is required to stretch/distend lungs
Surfactant ANS: Reduces surface tension; allows for more stretch to increase lung compliance
Simple Diffusion ANS: Lungs share thin basement membranes for easy gas exchange (diffusion); passive
Fick's Law ANS: Rate = change in concentration x membrane permeability / distance x molecular weight
Top is direct with rate
Inflammation ANS: Macrophages in area begin phagocytizing bacteria or other foreign invaders. Secrete
chemotaxins and cytokines that attract other phagocytes to the area and causes vasodilation/increased
permeability.
Increased blood flow to area and increased capillary permeability due to histamine. (redness - heat -
swelling)
,Fever ANS: Exogenous pyrogen (bacteria or the like) or endogenous (cytokines released by leukocytes)
cause hypothalamus to reset body temp
Raise in temperature helps body fight off pathogen, denature proteins, and force rest
Non-Specific Defenses ANS: Always on guard, rapid response, limited
Nonselective (every and all invaders)
Contains and limits spread of infection
B Cells ANS: Attack outside of the cell
Humoral immunity
Two types: active & passive
Active = produce antibodies
Passive = do not produce antibodies and do not produce an immune response
Active Naturally Acquired B Cells ANS: Occurs when a person is exposed to a live pathogen, and
develops a primary immune response
Active Artificially Acquired B Cells ANS: Can be induced by a vaccine, a substance that contains antigen.
A vaccine stimulates a primary response against the antigen without causing symptoms of the disease
, Passive Naturally Acquired B Cells ANS: When maternal antibodies are transferred to the fetus through
the placenta
Passive Artificially Acquired B Cells ANS: When high levels of antibodies specific to a pathogen or toxin
are transferred to non-immune persons through blood
IgM ANS: Antigen receptor on lymphocyte surface prior to immunization
Secreted during primary response
In the plasma
IgA ANS: Main antibody type in external secretions (saliva and mother's milk)
Binds to pathogen to prevent from entering body
IgD ANS: Antigen receptor on lymphocyte surface prior to immunization
On the surface of B Cells
IgG ANS: Main form of antibodies in circulation
Production is increased after immunization
Secreted during secondary response