System Respiratory Review Respiratory
Anatomy and Physiology of the Respiratory System Respiratory
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Air enters at the nose or mouth
warmed and moisturized
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Passes through the pharynx
warmed and moisturized
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Passes through the larynx
Anatomy and Physiology of the Respiratory System Respiratory
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Conducting Airways
Upper airways Trachea Bronchial tree
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Purposes
warm and humidify air prevent entry of foreign materials passage way to the alveoli Lined with mucociliary blanket
Anatomy and Physiology of the Respiratory System Respiratory
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Trachea
4.5 inches x 1 inch begins at the cricoid cartilage ends at the carina cartilaginous rings
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Right and Left Main Bronchi
Anatomy and Physiology of the Respiratory System Respiratory
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Terminal Bronchioles
Anatomic Dead Space
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Respiratory Bronchioles
Participate in gas exchange
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Alveolar Ducts
Two alveolar ducts branch from each Two respiratory bronchiole respiratory Surrounded by alveoli
Anatomy and Physiology of the Respiratory System Respiratory
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Alveoli
Functional unit of the respiratory system, Functional 300 million, large total surface area 300
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Type I Alveolar Cells
gas exchange
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Type II Alveolar Cells
Produce, store, and secrete surfactant
Anatomy and Physiology of the Respiratory System Respiratory
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Surfactant
lowers surface tension lubricates prevents the collapse of the alveoli iincreases lung compliance (ability to ncreases stretch) stretch) eases the work of breathing
Anatomy and Physiology of the Respiratory System Respiratory
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Deficiency of surfactant
alveolar instability alveolar collapse (atelectasis) impairment of gas exchange
preemies
Anatomy and Physiology of the Respiratory System Respiratory
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Right Lung
Three lobes
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Left Lung
Two lobes
Apices s Bases s Parietal and visceral pleura
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Anatomy and Physiology of the Respiratory System Respiratory
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Muscles of ventilation
Diaphragm External Intercostal Muscles Internal Intercostal Muscles Accessory Muscles
Anatomy and Physiology of the Respiratory System
Innervation s Bronchioles
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Parasympathetic (Bronchoconstriction) Sympathetic (Bronchodilation)
Respiratory Center
Pons and medulla (brainstem)
Anatomy and Physiology of the Respiratory System Respiratory
Elasticity (tissue recoil) is the tendency Elasticity of a structure to resist stretching, and when stretched will return to its normal shape shape s Permits Passive Expiration
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Anatomy and Physiology of the Respiratory System Respiratory
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Airway Resistance
Pressure which must be overcome to Pressure inflate the lungs inflate
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Resistance
nose (greatest) oropharynx larynx conducting airways- bronchioles conducting
Anatomy and Physiology of the Respiratory System Respiratory
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Inspiration
size of chest cavity increases diaphragm contracts and lowers intercostal muscles contract oxygen the enters body, air moves from oxygen area of greater pressure (atmosphere) to less pressure (lungs) less
Anatomy and Physiology of the Respiratory System Respiratory
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Expiration
Decrease in the size of the chest cavity Diaphragm relaxes and moves upward Intercostal muscles relax Rib cage returns to its resting state Carbon dioxide is exhaled
Anatomy and Physiology of the Respiratory System Respiratory
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Expiration
Airways decrease in size Alveolar ducts decrease in size
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Inspiration
Airways increase in size Alveoli increase in size
Anatomy and Physiology of the Respiratory System Respiratory
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Airway resistance
Increased in bronchoconstriction Airflow decreases
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Airway resistance
Decreased in bronchodilation Airflow increases
Anatomy of the Respiratory System System
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Upright Position
Bases aerate better than the apices
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Supine Position
No difference between the bases and the No apices apices
Anatomy and Physiology of the Respiratory System Respiratory
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Factors That Increase the Work of Factors Breathing Breathing
Decrease pulmonary compliance Increased airway resistance Active expirations Use of accessory muscles
Protective Mechanisms of Respiratory Systems: Respiratory
Nasal Hairs s Nasal Mucosa s Tonsils and adenoids s Ciliated epithelium s Mucus produced by goblet cells s Alveolar macrophages s Sneeze reflex s Cough reflex
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Gas Transport (part 1) Gas
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Ventilation
the exchange of air between the lungs and the the atmosphere the
Pulmonary ventilation Pulmonary
the total exchange of gas
Alveolar ventilation Alveolar
the effective ventilation of the alveoli
Gas Transport (part 2) Gas
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Perfusion
The flow of blood through the capillaries The surrounding the alveoli surrounding
Gas Transport (part 3) Gas
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Diffusion
Movement of gas across membrane
difference in pressure surface area thickness of alveoli/capillary type of gas
Ventilation/Perfusion Ventilation/Perfusion
V = alveolar gas flow (4 L/min) s Q = capillary blood flow (5 L/min)
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Ventilation/Perfusion Ventilation/Perfusion
Main purposes: R/O PE, determine lung Main function function s Normal V/Q Ratio
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4000 ml air 5000 ml blood
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Normal V/Q 0.8
Oxyhemoglobin dissociation curve Oxyhemoglobin
Oxygen Hemoglobin Dissociation Curve Curve
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There are certain conditions that will There result in a high or low affinity of oxygen to Hgb to
Oxyhemoglobin Dissociation Curve Curve
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Increased affinity of Hgb for O2
less oxygen is released to the tissues
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causes for this shift
alkalemia, hypocapnia, hypothermia
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Decreased affinity
More oxygen is released to the tissues
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causes for this shift
acidemia, hypercapnia
Pulmonary Function Tests Pulmonary
s Pulmonary
Function Tests
FVC FEV1
forced vital capacity forced expiratory volume 1 forced sec sec FEV1/FVC 80% TV tidal volume (at rest) TLC total lung capacity