Chapter 13
Respiration
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13-1
Objectives
13-2
Introduction
• Respiration
– A properly functioning respiratory system
is necessary for cell metabolism
– Without oxygen, cell metabolism becomes
less efficient and eventually stops
13-3
Physiology of Respiration
13-4
Pulmonary Ventilation
• Breathing
– Inspiration
– Expiration
• Residual volume
• Vital capacity
13-5
Tidal Volume and Minute Volume
• Tidal volume
– Amount of air moved into or out of the
lungs during a normal breath
– Tidal volume of a healthy adult at rest is
about 500 mL
• Minute volume
– Amount of air moved in and out of the
lungs in one minute
– Tidal volume x ventilatory rate
13-6
Pulmonary Ventilation
• Hypoventilation
• Hyperventilation
13-7
Oxygenation
• Oxygen content of the blood
– Oxygen carried by hemoglobin molecules
– Oxygen dissolved in the plasma
• Oxygenation
– The process of loading oxygen molecules
onto hemoglobin molecules
• Oxygen saturation
– A relative measure of the percentage of
hemoglobin bound to oxygen
13-8
Oxygenation
• Pulse oximeter
13-9
Oxygenation
• Hypoxemia
– A lack of oxygen in the arterial blood
• Hypoxia
– A lack of oxygen available to the tissues
13-10
External Respiration
• External respiration
– The exchange of gases between the
between the alveoli and the red blood cells
in the pulmonary capillaries.
• Optimal gas exchange requires:
– Good ventilation of the alveolus
– Good perfusion of its capillaries
13-11
Internal Respiration
• During internal respiration, energy is
released from glucose
– This process is called cellular respiration.
– Oxygen and carbohydrates produce
energy and create carbon dioxide and
water as a by-product of metabolism.
13-12
Pathophysiology of Respiration
13-13
Factors Necessary for Optimal Respiration
• Open (patent) airway
• Intact central nervous system
• Intact chest wall, pleura, respiratory organs,
respiratory muscles, and nerves that supply
these muscles
• Sufficient number of functioning alveoli
• Open pulmonary vessels
• Intact circulatory system and adequate
cardiac output
13-14
Disruption of Airway Patency
• Possible causes
– Loss of muscle tone
– Foreign body
– Infection (croup, epiglottitis)
– Swelling (trauma, burns)
– Hemorrhage
– Allergic reactions
– Trauma to the face or neck
13-15
Interruption of Nervous Control
• Stroke
• Brain injury
• Drugs
13-16
Dysfunction of the Thorax, Nerves, or
Respiratory Muscles
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Muscular dystrophy
Poliomyelitis
Spinal cord injury
Thoracic trauma
13-17
Examples of Conditions Affecting
Alveolar Function
•
•
•
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Emphysema
Pulmonary edema
Pneumonia
Asthma
13-18
Circulation Compromise
•
•
•
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•
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Pulmonary embolism
Tension pneumothorax
Cardiac tamponade
Heart failure
Hypovolemic shock
Cardiogenic shock
13-19
Assessment of Ventilation
13-20
B Is for Breathing
• Normal breathing is the mechanical process
of moving air into and out of the lungs
– Quiet
– Painless
– Occurs at a regular rate
– Both sides of chest rise and fall equally
– Does not require excessive use of:
• Muscles between the ribs
• Muscles above the collarbones
• Abdominal muscles
13-21
Breath Sounds
13-22
Breath Sounds
• Determine if breath sounds are:
– Present, diminished, or absent
– Equal or unequal
– Clear, muffled, or noisy
– Compare them bilaterally
13-23
Breath Sounds
• Normal breath sounds are clear and equal on
both sides of the chest.
– Diminished or absent lung sounds may be
caused by:
•
•
•
•
•
Spasm of the bronchioles
Foreign body
Pneumonia
Pneumothorax
Hemothorax
13-24
Breath Sounds
• Trauma, infection, pneumothorax, and
hemothorax are examples of conditions that
can produce unequal breath sounds.
13-25
Abnormal Breath Sounds
• Crackles (rales)
• Rhonchi
• Wheezes
13-26
Possible Causes of Wheezing
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Anaphylaxis
Asthma
Bronchiolitis
Bronchospasm
Chronic bronchitis
Croup
Emphysema
• Foreign body
obstruction
• Heart failure
• Inhalation injury
• Pulmonary edema
• Pneumonia
• Tumor
13-27
Is Ventilation Adequate?
• Responsive patient
– Ask “Can you speak?” or “Are you
choking?”
– If he can speak or make noise, air is
moving past his vocal cords
• Unresponsive patient
– Open the airway
– Look, listen, and feel for breathing
13-28
Is Ventilation Adequate?
• Signs of adequate ventilation
– Breathes at a regular rate and within
normal limits for his age
– Has an equal rise and fall of the chest with
each breath
– Has an adequate tidal volume
– Speaks in full sentences without pausing
to catch his breath
– Breath sounds are clear on both sides of
the chest
13-29
Is Ventilation Adequate?
• Signs of inadequate ventilation
– Anxious appearance
– Confusion, restlessness
– Unable to speak in complete sentences
– Abnormal work (effort) of breathing
– Abnormal breath sounds
13-30
Is Ventilation Adequate?
• Signs of inadequate ventilation
– Depth of breathing is unusually deep or
shallow
– A breathing rate that is too fast or slow for
the patient’s age
– An irregular breathing pattern
– Inadequate chest wall movement or
damage due to trauma
– Pain with breathing
13-31
Difficulty Breathing
• Working hard to breathe = labored breathing
• Patient may gasp for air
• Patient may use accessory muscles to
breathe
– Muscles in neck to assist with inhalation
– Abdominal muscles and muscles between
ribs to assist with exhalation
• Retractions
– “Sinking in” of soft tissues between and
around the ribs or above the collarbones
13-32
Position Changes
• A patient who is having difficulty breathing
often naturally assumes a position to
improve his breathing.
– Patient may instinctively avoid lying down
– Patient may increase the number of
pillows he uses at night in order
– Patient may prefer to sit and sleep in a
chair, such as a recliner.
– Patient may assume the tripod position.
13-33
Noisy Breathing
• Stridor
– Seal-like bark heard on inhalation
– Suggests partial upper airway obstruction
• Snoring
– Suggests the upper airway is partially obstructed
by the tongue
• Gurgling
– Wet sound
– Suggests that fluid is collecting in the upper
airway
– Immediate suctioning is needed
• Wheezing
– Whistling sound heard on exhalation
– Suggests partial obstruction of lower airways
13-34
Rate and Rhythm of Breathing
• Many factors affect a person’s rate of
breathing.
– Examples
• Sleep, fever, pain, emotions, drugs
• Examples of conditions affecting rhythm of
breathing
– Trauma to the head or brain may have an
abnormal breathing pattern
– Stroke
– Diabetic emergencies
– Toxic exposures.
13-35
Chest Expansion
• Observe the rise and fall of the patient’s
chest.
• Possible causes of unequal chest expansion
– Flail chest
• Paradoxical chest movement
– Pneumothorax
– Pneumonia
13-36
Respiratory Distress and Failure
• Respiratory distress
– Increased work of breathing (ventilatory
effort)
• Respiratory failure
– Inadequate blood oxygenation and/or
ventilation to meet demands of body
tissues
– Patient looks very sick
• Signs of greatly increased work of breathing
usually present
• Skin may appear pale, mottled, or blue
13-37
Respiratory Arrest
• Signs and symptoms of respiratory arrest:
– Agonal breathing
– Unresponsiveness
– No air movement from the mouth or nose
– No chest rise and fall
– Changes in skin color
13-38
Assessment of Oxygenation
13-39
Adequate Oxygenation
• Signs of adequate oxygenation
– Does not appear to be in distress
– Has a mental status that is normal for that
patient
– Has normal skin color
13-40
Inadequate Oxygenation
• Signs of inadequate oxygenation
– Oxygen concentration in surrounding air is
abnormal
• Enclosed space, poisonous gas, high altitude
– Color of the patient’s skin and mucous
membranes is abnormal
• Skin looks flushed, pale, gray, or blue
13-41
Pulse Oximetry
• Pulse oximetry
– The oximeter calculates the amount of
hemoglobin saturated with oxygen.
– This calculation is called the saturation of
peripheral oxygen (SpO2).
13-42
Pulse Oximetry
13-43
Pulse Oximetry
• Pulse oximetry is a routine vital sign that
should be obtained on all patients.
SpO2
95% - 100%
Meaning
Adequate oxygenation
91% - 94%
86% - 90%
Below 85%
Mild hypoxia
Moderate hypoxia
Severe hypoxia
13-44
Pulse Oximetry
Indications
• Altered mental status
• Ventilatory rate outside the normal range for
age
• Increased work of breathing
• Respiratory or cardiac chief complaints
• History of respiratory difficulty or respiratory
disease
• During delivery of supplemental oxygen
• During and after endotracheal intubation
• During transport of a sick or injured child
13-45
Pulse Oximetry
• Examples of conditions that may cause
inaccurate pulse oximetry readings:
– Cardiac arrest
– Shock
– Hypothermia
– Carbon monoxide poisoning
– Sickle-cell disease
– Patient movement, shivering
– Patient use of nail polish
13-46
Supplemental Oxygen
13-47
Oxygen Delivery Systems
13-48
Oxygen Cylinders
Cylinder Type
Amount of Oxygen in Liters
Portable
D
350
E
625
Onboard
M
3450
G
5300
H
6900
13-49
Using Oxygen Safely
13-50
Pressure Regulators
13-51
Flow Meters
13-52
Setting Up an Oxygen Delivery System
13-53
Setting Up an Oxygen Delivery System
13-54
Setting Up an Oxygen Delivery System
13-55
Setting Up an Oxygen Delivery System
13-56
Setting Up an Oxygen Delivery System
13-57
Setting Up an Oxygen Delivery System
13-58
Setting Up an Oxygen Delivery System
13-59
Setting Up an Oxygen Delivery System
13-60
Discontinuing an Oxygen Delivery System
13-61
Discontinuing an Oxygen Delivery System
13-62
Discontinuing an Oxygen Delivery System
13-63
Discontinuing an Oxygen Delivery System
13-64
Oxygen Humidifier
13-65
Oxygen Delivery Devices
13-66
Nonrebreather (NRB) Mask
13-67
Partial Rebreather Mask
13-68
Venturi Mask
13-69
Nasal Cannula
13-70
Blow-By Oxygen
13-71
Questions?
13-72