Week 5
Oxygenation and Tissue
Perfusion
Learning Objectives
1. Describe and list factors that affect oxygenation
and tissue perfusion.
2. Explain common physical assessment procedures
used to evaluate respiratory health of patients
across the lifespan.
3. Identify priority respiratory assessment findings.
4. Differentiate normal respiratory assessment from
abnormal findings.
Learning Objectives (cont’d.)
5. Describe the integral relationship between
perfusion and oxygenation.
6. Explain the role and limitations associated
with pulse oximetry assessment.
7. Explain and utilize vital signs and peripheral
vascular assessment techniques and findings
to assess perfusion.
Oxygenation
• Definitions
• Oxygenation: mechanisms that facilitate or
impair body’s ability to supply oxygen to
cells
• Respiration : act of inhaling and exhaling air
to transport oxygen to alveoli
• So oxygen may be exchanged for carbon dioxide
• Carbon dioxide expelled from body
• Ventilation : actual exchange of oxygen and
carbon dioxide (Breathing)
Definitions (cont’d)
• Diffusion- The movement of a substance from
an area of high concentration to an area of
low concentration (Gas exchange).
• Perfusion – A continuous supply of oxygenated
blood to every cell in the body (Pumped to all
parts).
Three main components/concepts to
oxygenation of the body:
•Ventilation – Breathing
•Diffusion- Gas exchange
•Perfusion – pumped to all parts
Normal Presentation:
• Adequate Oxygenation:
– Depends on healthy intact respiratory system
– Upper respiratory system
• Inlet for air into body
• Inlet  typically nose
• Breathing also through mouth
Ventilation: The exchange of oxygen and
carbon dioxide. (Air moving in and out of
the lungs.)
Average Respiratory Rates:
*Infants: About 30 breaths per minute
*Preschooler: Around 25 breaths per minute
*Adolescents & Adults: 12- 18 breaths per minute
Hypoxemia:
Decreased level of oxygen
First signs of hypoxia may
include:
Anxiety, restlessness, and/or
confusion
Cyanosis:
Late sign of hypoxemia and is seen as
a blue tinge to the skin
Cyanosis is a late sign of
hypoxemia
Impaired Oxygenation:
Can be life-threatening
Mild to severe
Diseases, injuries
Frightening, frustrating
Assessment:
What do you see?
(Examples include restlessness,
anxiety, gasping, cyanosis, shortness
of breath, increased respiratory
rate?)
Assessment:
What do you hear?
(With your ears and/or with
your stethoscope…)
Normal breath sounds are the
inspiratory and expiratory sounds
heard through the chest wall of a
healthy individual.
Do you hear coughing,
wheezing, gasping, or any
other sounds during
breathing?
Q. Ventilation is also known as
_______?
a. Wheezing
b. Pneumonia
c. Breathing
d. Lung Abscess
c. Breathing
Quality of breathing requires
a patent airway, one that is
open and free of obstruction.
A priority for the nurse is to always make
certain the patient has a patent airway!
Airway patency is a priority
with patient status changes,
facial/dental surgery, upper
respiratory tract obstruction,
and emergency situations!
Swollen Tongue:
Definitely an airway issue
since this affects ventilation!
When edema and swelling of the
trachea/airway occur in response to a
virus, bacterium, or other irritant, the
airway is further narrowed.
Think of diffusion as oxygen getting
into the blood and carbon dioxide
getting out…
(Remember: gas exchange.)
* Hemoglobin is the oxygen-carrying molecule
within the red blood cells (RBC’s).
* No RBC’s or hemoglobin; no oxygen!
* Pulse Oximeter measures percentage of
oxygen attached to hemoglobin
Oxygen Saturation:
Pulse Oximeter is used to measure the
percentage of
oxygen attached to hemoglobin
When assessing respiratory status
changes, determine if the patient is…
*Short of breath and/or in respiratory distress?
*Involved in or just completing physical activity or
exertion causing increased respiratory rate (P.T. or up
to the bathroom)?
*Is pulse ox is attached properly and turned on?
*Are they comfortable only when sitting upright and
slightly forward with legs down? (See next slide)
Tripod Position: Leaning forward
with the hands on the knees
Q. What is the first thing you
do when someone has difficulty
breathing?
a. Have them raise their feet
b. Sit them up in high upright position
c. Give them water to drink
d. Take their blood pressure
b. Sit them in an upright position
End of Week 5