Transcript Bronchiolitis - Denver School of Nursing

Denver School of Nursing – ADN & BSN Programs
No Laboratory component for this class
BIO 206 & 308 – Ch 25 & 26 – Pulmonary Phys / Path
What are the three most important structures
of the Respiratory System???
What are the three most important structures
of the Respiratory System???
1. Lungs – WHY?
2. Muscles of Respiration – WHY?
3. Brain – WHY?
Primary =
Secondary =
Tertiary=
Muy Importante!=
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The Respiratory System is divided into two
general parts:
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The Upper Respiratory Tract
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The Lower Respiratory Tract
Where do you think the division starts?
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What is the respiratory mucosa?
Proper Definition:
 From A&P Thibodeau: “Mucous membranes are
epithelial membranes that line body surfaces
opening directly to the exterior (latin name,
mucosa)... Their name is derived from the fact
that they produce a film of mucus that coats and
protects the underlying cells.”
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In addition to protection, the mucus has other
purposes, can you tell me what they are??
Function of Mucosa:
 Protection – for underlying tissue
 Immune Support!
 Mechanically capture debris
 Presence of “mucins” (proteoglycans)
 Bacterial interface
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Lubricant – to allow food to move in digestive
tract, and if aspiration occurs in respiratory
tract the mucosa will also allow for the
pleasantry of “regurg” / emesis.
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Nose
Pharynx
Larynx
Trachea
Bronchi
Bronchioles
Alveoli
Lungs
Pleura
What is the purpose and
function of each of these
structures???
Remember what these
are REALLY called?
Bronchioles 
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What are the serious membranes in the body?
Image from http://www.augustatech.edu/anatomy
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Where are the 3 primary serous membranes
found in the human body?
Image from http://www.augustatech.edu/anatomy
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Serous membranes: Heart, lungs, GI
Image from http://www.augustatech.edu/anatomy
Illustration of the mechanism of respiration
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Major and accessory muscles
 Major muscles of inspiration
▪ Diaphragm
▪ External intercostals
 Accessory muscles of inspiration
▪ Sternocleidomastoid and scalene muscles
 Accessory muscles of expiration
▪ Abdominal and internal intercostal muscles
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Alveolar surface tension and ventilation
 Function of surfactant
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Elastic properties of the lung and chest
wall
 Elastic recoil
 Compliance
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Airway resistance
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Work of breathing
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Four steps
 Ventilation of the lungs
 Diffusion of oxygen from the alveoli into
the capillary blood
 Perfusion of systemic capillaries with
oxygenated blood
 Diffusion of oxygen from systemic
capillaries into the cells
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Diffusion of CO2 occurs in reverse
order
IN the PONS (of the Brain Stem)
1) Apneustic Center
Stimulates neurons to promote
Inspiration via External
intercostals and the diaphragm
2) Pneumotaxic Center
Stimulated neurons to promote
Expiration via the Internal
intercostals and rectus abdominis
Neurochemical control
Respiratory center
▪ Dorsal respiratory group
▪ Ventral respiratory group
▪ Pneumotaxic center
▪ Apneustic center
Chemoreceptors
1) Central Chemoreceptors
~ located in the medulla
2) Peripheral Chemoreceptors
~ located in the Aorta &
the carotid bodies
Both detect increased levels in
Carbon Dioxide, and then
stimulate Increase in RR
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Ventilate the alveoli
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Diffuse gases into and out of the blood
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Perfuse the lungs so the body receives oxygen
 Ventilation
 Mechanical movement of gas or air
into and out of the lungs
 Minute volume
▪ Ventilatory rate multiplied by the volume of air per
breath
 Alveolar ventilation
Lung Volume chart
Image Source: http://www.anaesthetist.com
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Spirometry
Diffusion capacity
Residual volume
Functional reserve capacity (FRC)
Total lung capacity
Arterial blood gas analysis
Chest radiographs
 Conducting
airways
 Upper airways
▪ Nasopharynx
▪ Oropharynx
 Larynx
▪ Connects upper and lower airways
 Lower airways
▪ Trachea
▪ Bronchi
▪ Terminal bronchioles
 Gas-exchange
airways
 Respiratory bronchioles
 Alveolar ducts
 Alveoli
▪ Epithelial cells
▪ Type I alveolar cells
 Alveolar structure
 Where diffusion of Respiratory gasses occurs
▪ Type II alveolar cells
 Surfactant production
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Pulmonary circulation has a lower
pressure than the systemic circulation
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One third of pulmonary vessels are
filled with blood at any given time
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Pulmonary artery divides and enters the
lung at the hilus
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Each bronchus and bronchiole has an
accompanying artery or arteriole
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Alveolocapillary membrane
 Formed by the shared alveolar and capillary
walls
 Gas exchange occurs across this
membrane
 Membrane formed by what cells?
 Barometric
pressure
 Partial pressure
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Partial pressure of water vapor
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Barometric
pressure
 Partial
pressure
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Speaking of partial
pressure…
Have you ever wondered
what the partial
pressure of O2 is at sea
level is?
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Distribution of ventilation and perfusion
 Gravity and alveolar pressure
 Ventilation-perfusion ratio(0.8)
 Oxygen
transport
 Diffusion across the
alveolocapillary
membrane
 Determinants of arterial oxygenation
▪ Hemoglobin binding, oxygen saturation
 Oxyhemoglobin association and
dissociation
▪ Oxyhemoglobin dissociation curve
▪ Bohr effect
 Carbon dioxide transport
 Dissolved in plasma
 Bicarbonate(HCO3)
 Carbamino compounds (hemaglobin)
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Haldane effect
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Dissolved in plasma-Pco2
 Arterial -5%
 Venous-10%
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Bicarbonate-HCO3
 Arterial-90%
 Venous-60%
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Carbamino compounds-Hb
 Arterial-5%
 Venous-30%
 Hypoxic pulmonary vasoconstriction
 Caused by low alveolar PO2
 Blood is shunted to other, well-ventilated
portions of the lungs
▪ Provides better ventilation and perfusion matching
▪ If hypoxia affects all segments of the lungs, the
vasoconstriction can result in pulmonary
hypertension
Acidemia also causes pulmonary
artery constriction
Image Source: http://www.gilmerfreepress.net
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Dyspnea
 Subjective sensation of uncomfortable
breathing
 Orthopnea
▪ Dyspnea when a person is lying down
 Paroxysmal nocturnal dyspnea
(PND)
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Dyspnea
 Subjective sensation of uncomfortable
breathing
 Orthopnea
▪ Dyspnea when a person is lying down
 Paroxysmal nocturnal dyspnea
(PND)  Generally w LV Failure
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Abnormal breathing patterns
 Kussmaul respirations (hyperpnea)
 Cheyne-Stokes respirations
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Hypoventilation
 Hypercapnia
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Hyperventilation
 Hypocapnia
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Cough
 Acute cough
 Chronic cough
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Hemoptysis
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Cyanosis
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Pain
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Clubbing
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Abnormal sputum
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Hypercapnia
Hypoxemia
 Hypoxemia versus hypoxia
 Ventilation-perfusion abnormalities
▪ Shunting
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Acute respiratory failure
Pulmonary edema
 Excess water in the lungs
What is missing
from this cartoon?
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Aspiration
 Passage of fluid and solid particles into the lungs
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Atelectasis
 Compression atelectasis
 Absorption atelectasis
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Bronchiectasis
 Persistent abnormal dilation of the bronchi
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Squeeze
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Bronchiolitis
 Inflammatory obstruction of the small
airways
 Most common in children
 Occurs in adults with chronic bronchitis,
in association with a viral infection, or
with inhalation of toxic gases
 (50% of the time due to what virus??)
 Bronchiolitis
obliterans
 Late-stage fibrotic disease of the airways
 Can occur with all causes of bronchiolitis
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Pneumothorax
 Open pneumothorax
 Tension pneumothorax
 Spontaneous pneumothorax
 Secondary pneumothorax
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One way
valve
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Pleural effusion
 Transudative effusion
 Exudative effusion
 Hemothorax
 Empyema
▪ Infected pleural effusion
 Chylothorax
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Pleural
space
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Blood
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Abscess formation and cavitation
 Abscess
 Consolidation
 Cavitation
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Pulmonary fibrosis
 Excessive amount of fibrous or
connective tissue in the lung
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Chest wall restriction
 Compromised chest wall
▪ Deformation, immobilization, and/or obesity
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Flail chest
 Instability of a portion of the chest wall
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Inhalation disorders
 Exposure to toxic gases
 Pneumoconiosis
▪ Silica
▪ Asbestos
▪ Coal
 Allergic alveolitis
▪ Extrinsic allergic alveolitis
▪ (hypersensitivity pneumonitis)
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Acute respiratory distress
syndrome (ARDS)
 Fulminant form of
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respiratory failure
characterized by acute lung
inflammation and diffuse
alveolocapillary injury
Injury to the pulmonary capillary
endothelium
Inflammation and platelet activation
Surfactant inactivation
Atelectasis
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Acute respiratory distress
syndrome (ARDS)
 Manifestations
▪ Hyperventilation
▪ Respiratory alkalosis
▪ Dyspnea and hypoxemia
▪ Metabolic acidosis
▪ Hypoventilation
▪ Respiratory acidosis
▪ Further hypoxemia
▪ Hypotension, decreased cardiac output, death
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Acute respiratory distress
syndrome (ARDS)
 Evaluation and treatment
▪ Physical examination, blood gases, and
radiologic examination
▪ Supportive therapy with oxygenation and
ventilation and prevention of infection
▪ Surfactant to improve compliance
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Postoperative respiratory failure
 Atelectasis
 Pneumonia
 Pulmonary edema
 Pulmonary emboli
 Prevention
▪ Frequent turning, deep breathing, early
ambulation, air humidification, and incentive
spirometry
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Airway obstruction that is worse with
expiration
Common signs and symptoms
 Dyspnea and wheezing
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Common obstructive disorders
 Asthma
 Emphysema
 Chronic bronchitis
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“Chronic inflammatory disorder of the
airways”
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Inflammation results from
hyperresponsiveness of the airways
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Can lead to obstruction and status
asthmaticus
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Symptoms include expiratory wheezing,
dyspnea, and tachypnea
Peak flow meters, oral corticosteroids,
inhaled beta-agonists, and antiinflammatories used to treat
 Chronic
bronchitis
 Hypersecretion of mucus and chronic
productive cough that lasts for at least
3 months of the year and for at least 2
consecutive years
 Inspired irritants increase mucus
production and the size and number of
mucous glands
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Chronic bronchitis
 The mucus is
thicker than normal
 Bronchodilators, expectorants, and
chest physical therapy used to treat
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Emphysema
 Abnormal permanent enlargement of the
gas-exchange airways accompanied by
destruction of alveolar walls without
obvious fibrosis
 Loss of elastic recoil
 Centriacinar emphysema
 Panacinar emphysema
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ULL
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Pneumonia
 Community-acquired pneumonia
▪ Streptococcus pneumoniae
 Hospital-acquired (nosocomial) pneumonia
 Pneumococcal pneumonia
 Viral pneumonia
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Lobar
 Tuberculosis
 Mycobacterium tuberculosis
 Acid-fast bacillus
 Airborne transmission
 Tubercle formation
 Caseous necrosis
 Positive tuberculin skin test (PPD)
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Cavitary
 Acute
bronchitis
 Acute infection or inflammation of the
airways or bronchi
 Commonly follows a viral illness
 Acute bronchitis causes similar
symptoms to pneumonia but does
not demonstrate pulmonary
consolidation and chest infiltrates
 Pulmonary
embolism
 Occlusion of a portion of the pulmonary
vascular bed by a thrombus, embolus,
tissue fragment, lipids, or an air bubble
 Pulmonary emboli commonly arise from
the deep veins in the thigh
 Virchow triad
▪ Venous stasis, hypercoagulability, and
injuries to the endothelial cells that line the
vessels
 Pulmonary
hypertension
 Mean pulmonary artery pressure 5 to 10
mm Hg above normal or above 20 mm
Hg
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Pulmonary hypertension
 Classifications
▪ Pulmonary arterial hypertension
▪ Pulmonary venous hypertension-CHF
▪ Pulmonary hypertension due to a respiratory
disease or hypoxemia-COPD
▪ Pulmonary hypertension due to thrombotic or
embolic disease-PE
▪ Pulmonary hypertension due to diseases of the
pulmonary vasculature
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Primary pulmonary hypertension
 Idiopathic
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Diseases of the respiratory system
and hypoxemia are more common
causes of pulmonary hypertension
 Pulmonary
heart disease
 Right ventricular enlargement
 Secondary to pulmonary hypertension
 Pulmonary hypertension creates chronic
pressure overload in the right ventricle
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Lip cancer
Most common form
 Exophytic
 Stages
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Laryngeal cancer
 Forms
▪ Carcinoma of the true vocal cords (most
common)
▪ Supraglottic
▪ Subglottic
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Bronchogenic carcinomas
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Most common cause is cigarette
smoking
 Heavy smokers have a
20 times’
greater chance of developing lung
cancer than nonsmokers
 Smoking is related to cancers of the
larynx, oral cavity, esophagus, and
urinary bladder
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Environmental or occupational
risk factors are also associated
with lung cancer
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of Pathopysiology!!
Remember to…
KEEP UP WITH YOUR:
1) Text READING
2) Powerpoint Review
3) Study Guide Prep