FUNDS NR 224 Week 4 Lesson 5 Fundamentals in Nursing Ventilation and Oxygenation Study Guide. A+ Guide.Introduction
This lesson will describe assessment
... [Show More] of respirations (ventilation) and blood oxygenation. As with other vital
signs, it is important to accurately measure and document patient respiration and oxygen saturation levels to
ensure rapid response to ventilation and oxygenation alterations.
Upon completion of this lesson, you will be able to:
Describe assessment of respirations and measurement of blood oxygenation.
Identify nursing diagnoses related to ventilation and oxygenation.
Vital Signs
Breathing (pulmonary ventilation) refers to the movement of air into the lungs (inspiration) and out of the lungs
(expiration). Although breathing is normally passive, muscular work is involved in moving the lungs and chest
wall. Both inspiration and expiration should be smooth and without conscious effort.
Importance of Ventilation and Oxygenation
It is important to understand the physiological processes and control necessary for respiration and oxygenation,
as well as its measurement.
Gas Exchange
Respiration is the mechanism by which oxygen and carbon dioxide are exchanged between the outside of the
body and the blood and further exchanged between the blood and cells.
Ventilation is the movement of oxygen and carbon dioxide in and out of the lungs or inhaling and exhaling.
Diffusion is the exchange of oxygen between alveoli and red blood cells.
Perfusion is the movement of red blood cells carrying oxygen to tissues and cells (capillary bed) and the removal
of carbon dioxide.
These physiological processes work together to meet the oxygen needs of the body.
Physiological Control
The cerebral cortex of the brain allows voluntary control of breathing, for example, when singing.
But respiration also occurs without voluntary control. Chemoreceptors located throughout the body
stimulate respiratory centers in the medulla and pons.
Chemoreceptors in the aortic arch and carotid arteries react to hypoxemia (low oxygen levels in the
blood).
Receptors in the medulla react to high levels of carbon dioxide (hypercapnia) and changes in pH. This
push-pull between the two groups of receptors creates breathing.
Stretch receptors in the lungs and receptors in muscles and joints provide input to the medulla and pons.
Assessment
Respiration and ventilation are assessed by measuring:
Respiratory rate (breaths per minute, BPM, or bpm); 12 to 20 bpm is optimal for an adult
Respiratory depth (shallow, normal, deep)
Respiratory rhythm (regular, labored, irregular)
Diffusion and perfusion are assessed by measuring oxygen saturation.
Diaphragmatic breathing results from contraction and relaxation of the diaphragm.
Normal Respiration and Oxygenation Parameters
Human survival depends on the ability of oxygen to reach body cells and carbon dioxide to be removed from the
cells. Oxygen saturation reflects the amount of oxygen that actually enters the bloodstream.
In the table below, optimal ranges of respiratory rate and oxygen saturation are shown by age. Note: “Rate” is
expressed as breaths per minute.
Acceptable Ranges of Respiratory Rate
Age Rate SpO2
Newborn 30-80 >95%
1 year old 24-40 >95%
6 years old 15-25 >95%
15 years old 15-20 >95%
Adult 12-20 >95%
Older adult 15-20 >95%
Rate, Depth, and Quality
The process of assessing respirations includes measuring the breathing rate, depth, and rhythm. The patient’s
normal respiratory pattern provides a baseline, which is used to identify later alterations if they occur.
Rate
Eupnea refers to normal respiratory rate and depth.
Tachypnea is an increase in respiratory rate to more than 24 bpm in an adult patient.
Bradypnea is a decrease in respiratory rate to less than 10 bpm in an adult patient.
Depth
Respiratory depth can normally vary from shallow to deep.
Hypoventilation consists of shallow respirations, usually associated with drug overdoses, chronic
obstructive pulmonary disease, cervical spine injuries, and obesity.
Hyperventilation refers to a deep, rapid respiration pattern. It is associated with conditions such as
anxiety, stress, lung disease, and hard exercise.
Quality
Respiratory quality can be influenced by apnea, the absence of breathing. Brain damage occurs after 4 to 6
minutes of apnea.
Dyspnea is difficult or labored breathing. It can also be a rapid, shallow pattern of breathing that is
painful.
Orthopnea is difficulty breathing experienced in a position other than sitting or standing.
Interpretation of Vital Signs
Environmental or physiological factors may cause increases or decreases in respiratory rate and depth. These
factors include:
Age: Respiratory rate decreases with age through late adolescence, when it stabilizes.
Exercise: Respiratory rate and depth increase with exercise.
Illness processes: Cardiovascular disease and hematologic disorders such as anemia cause an increased
respiratory rate. Sickle cell disease reduces the ability of hemoglobin to carry oxygen, resulting in
increased respiratory rate and depth. Respiratory diseases can be manifested by difficulty breathing, use
of accessory muscles, increased rate, and shallower depth. Smoking alters airways, resulting in an
increased rate.
Acid-base balance: Acidosis results in increased rate and depth of respirations in an attempt to rid the
body of excess carbon dioxide. Alkalosis results in decreased respiratory rate as the body tries to retain
carbon dioxide.
Medications: Some medications, such as narcotics and general anesthesia, slow respirations.
Alternatively, drugs such as amphetamines and cocaine increase respirations. Bronchodilators slow the
respiratory rate by dilating the airways.
Pain: Acute pain increases respiratory rate while decreasing respiratory depth.
Emotions: Fear or anxiety can cause increased respiratory rate and decreased depth. [Show Less]