• Ventilation
• Perfusion
• Diffusion

• Type I
• Type II
• Macrophages

Pulmonary vs Systemic Circulation

as it relates to blood pressure

• Pulmonary is LOW pressure (25/8 mmHg)
• Systemic is HIGH pressure (120/80 mmHg)

• Upper Airway
• Lower Airway

• Nasopharyngeal Cavity which consists of:
• Nasopharynx
• Oropharynx
• Laryngopharynx

• Larynx
• Trachea
• Bronchi
• Bronchopulmonary Segments
• Terminal Bronchioles
• Acinus

• Mucociliary System
• Alveolar Macrophages

• Nasal Cavity Hairs (Vibrissae)
• Tracheobronchial Lining (Pseudostratified, ciliated columnar epithelium and goblet cells)
• Cilia (Provide defense in tracheobronchial tree)

• Via Ach and muscarine
• Muscarine receptors activated by acetylcholine
• Stimulation via the vagus nerve leads to bronchoconstriction

• Via B2
• B2 receptors present on smooth muscle
• Adrenergic receptors activated by epi
• Leads to bronchodilation

• Bronchial Artery System
• Pulmonary Artery System
• Capillary System
• Fluid Balance

• Capillary network for CO2 and O2 exchange
• Supplies oxy blood to the heart

• Hydrostatic Pressure
• Colloid Osmotic Pressure
• Capillary Permeability

• Recruitment
• Distension

• Down during inspiration
• Up during expiration

• As radius of airway decreases, the resistance increases
• Determined by the relationship between pressure and flow
• Resistance = Pressure Difference/Rate of Airflow

• Alveolar Septa
• Bronchi
• Bronchioles

• Neonates
• High Tidal Volumes (greater than 1500 ml)

• Aortic Arch
• Carotid Arteries

• Upper - Blood Flow Decr
• Lower - Blood Flow Incr

• Zone 1 - Upper/Apical
• Zone 2 - Middle
• Zone 3 - Base

• Zone 3
• Alveoli are smaller in the bases, leading to greater capillary expansion and greater blood flow

• Ventilation is higher than perfusion
• Usually caused by perfusion being blocked or reduced

• Incr dead space
• PE
• MI
• Pneumonia

• Ventilation is lower than normal
• Perfusion is ok, but something is getting in the way of ventilation, either mechanically or otherwise

• Low PaO2/hypoxemia
• R-L shunt

• Surfactant
• Alveolar Membrane
• Interstitial Fluid
• Capillary Membrane
• Plasma
• RBC Membrane

pathway begins with injury or immune response. Macrophages stimulate secretion of inflammatory cytokines PG, LT => inflammation

• Vasodilation
• Incr vascular permeability
• Inhibition can lead to bronchoconstriction (ASA, NSAIDs)

• Vasoconstriction
• Bronchospasm
• Incr vascular permeability

• Immune-mediated Airway Inflammation
• Obstructive Pulmonary Disorder
• Allergen + IgE > Mediators (histamine, LT, PG, IL) = Bronchoconstriction, inflammation, bronchial hyperactivity

• Airways
• Alveoli

External agents

Type I, IgE driven

• dust
• animal dander
• pollen
• etc...

• Thickened, narrowed lumen
• Hypertrophy of mucous glands
• Hypertrophied smooth muscle

• Wheezing is not a reliable indicator of blockage
• Severe obstruction reduces airflow, decreasing wheezing (bad sign)
• Wheezing actually increases as patient improves
• Sign of moving air

• Avoid allergic triggers
• O2, possibly mechanical ventilation
• Chest physiotherapy
• Inhaled bronchodilators
• Inhaled steroids (oral, IV, as well)
• Mast cell stabilizers

• Alveolar macrophage engulfs bacilli
• T cells and macrophages surround and form granulomas
• Caseous necrosis occurs
• Fibrosis, calcification (this is the Grohn tuburcle)

• Acid-fast Bacilli
• Ability to hold a stain, even after washing with acid

• Air can flow into the room, but not out
• It prevents TB infection from escaping

• Elderly
• Communal Living
• Incarcerated
• Foreign-born
• Homeless
• IV Drug Users
• Immunocompromised

• Droplets coughed or sneezed into the air
• Inhaled or ingested into host

• 1-2 hours
• Sterilized by sunlight
• Dispersed by wind
• Preserved in moisture and darkness for hours to months

• Fatigue, weakness, anorexia, weight loss
• Night sweats, low-grade fever
• Cough > 2 months, blood-tinged sputum

• White dots/masses (granuloma)
• apex and posterior segments of upper lobes

• Cardiogenic
• Noncardiogenic

• Generally left ventricular failure  
• Fluid builds up in left ventricle →left atrium →pulmonic circuit → alveoli

• Damage to capillary endothelium 
• Blockage of lymphatic vessels which help to drain fluid before it gets to alveoli
• Capillary damage = incr permeability of protein and fluid in alveoli

• Severe trauma/burn
• O2 toxicity
• Reduced perfusion
• Drugs
• Fat embolism
• Chest trauma
• Chemical inhalation
• Infection
• Microemboli
• Neurogenic factors

·         Causes of ARDS → Diffuse alveolar-capillary wall injury → alveolar-capillary leak → Pulmonary Edema (via incr pulmonary capillary pressure, reduced oncotic pressure, and loss of surfactant)

• Chronic Bronchitis
• Emphysema

• Persistant cough with sputum for at least 3 months out of the year for 2 consecutive years
• Excessive mucous production in the bronchial tree

• Abnormal and permanent enlargement of the acini
• Destruction of alveolar walls
• Loss of elastic recoil

• SOB
• DOE
• Wheeze
• Fatigue
• Productive Cough
• Cyanosis
• Co Pulmonale (late stages)

• Occurs in late stages
• Right ventricular hypertrophy

·         Hypoxemia will occur as chronic bronchitis progresses from abnormal V/Q ratio which can lead to cor pulmonale as a result of pulmonary hypertension

·         Hypoxemia can lead to polycythemia

(polycethemia related to nocternal hypoxemia)

• Excessive mucous resulting from hypertrophy and hyperplasia of mucous-producing cells of the bronchi
• Cell lining becomes dysfunctional, and undergoes metaplasia
• Mucous creates a breeding ground for infection, leading to inflammation, leading to edema

• Loss of elasticity of lungs (elastic recoil)
• Reduction in alveolar surface
• Elastin and collagen fibers are destroyed by products produced by alveolar macrophages

• Incr in number, trying to phagocytose the tars deposited in the lungs from smoking
• They release a proteolytic enzyme called elastase, which either destroys the alveolus or at least degrades the elastic tissue in the alveoli, reducing elastic recoil

• Flattening of the diaphragm from hyperinflation
• over distension of lung fields
• Incr AP diameter to chest (barrel-chested)

• Alveoli fill with inflammatory exudates
• Lungs become more non-compliant
• Infection, trauma, inflammation shut down gas exchange

• Immunocompromised
• Hospitalized
• Very Young
• Very Old
• Chronic Illness
• Viral Respiratory Illness
• Over 65
• Impaired Gag/Swallow Reflex
• Prolonged Bed Rest/Immobility

• Decreased breath sounds over consolidation
• Dullness to percussion
• Incr tactile fremitis
• Egophany (e sounds like a)

• Consolidation
• Tachypnea, labored breathing, accessory muscle use
• Incr WBCs, fever, shaking, chills
• Chest pains, HA, cough, anorexia, myalgias
• Tripoding, cyanotic

• O2 sat (pulse ox)
• Sputum culture (Gram stain to identify bug)
• ABG for oxygenation status (hypoxias)
• CXR for consolidation
• CBC for leukocytosis
• PPD to rule out TB

• Inflammation due to capillar dilation
• Swelling from exudation of fluid
• Infiltration with inflammatory cells
• Incr mucous production
• Loss of ciliary function/loss of portions of ciliated epithelium

• Venous stasis (alterations in normal blood flow)
• Injury to venous wall
• Hypercoagulability of blood

• Thrombolitic
• Fat
• Amniotic
• Air
• Tumor
• Foreign Material
• Septic
• Parasitic

• Lung collapse
• Respiratory distress from no gas exchange on the affected side
• Mediastinal shifting, which can crush great vessels

• Autosomal recessive disorder
• Disorder of Na+ and Cl- channels causes very thick mucous secretions and subsequent plugging of airways

• Lungs
• Pancreas

• Emphysema
• COPD

• DVT
• PE

• TB (tuburcles)
• Pneumonia (consolidation)

PPD

purified protein derivative

o   edema

o   mucous plugging/excessive secretion

o   smooth muscle hypertrophy

o   bronchial hyperactivity

Is pneumonia a restrictive or an obstructive disorder?

explain

Pneumonia is a restrictive disorder of lung parenchyma

Alveoli fill up with inflammatory exudate, edema occurs and lung becomes increasingly non-compliant

• decreased
• decreased