Restrictive Lung Diseases Flashcards
Restrictive Lung Diseases
Description & Key Characteristics
Diseases that restrict the lung from expanding fully
Ex. chest wall (boney), muscular (NM diseases), parenchyma
DEC compliance > DEC negative pressure > DEC air entry
- Inspiratory problem
- NEED (-) pressure in lungs compared to the atmosphere (high-low pressure)
- Volume of air in the lungs is decreased (DEC ventilation - V/Q mismatch)
Results in INC work of breathing:
- INC RR (may lead to hyperventilation: DEC PaCO2)
- INC accessory mm use
- INC pressure required to maintain lung expansion & ventilation (exert against a greater pressure)
- INC fatigue - poor ventilation = DEC O2 in system to supply tissue = fatigue easier
Restrictive Lung Diseases
(4)
- Interstitial Pulmonary Fibrosis
- Sarcoidosis
- Atelectasis
- ARDS
Interstitial Pulmonary Fibrosis
Definition
Thickening of the interstitium of the alverolar walls which progress to fibrosis or scarring
Interstitial Pulmonary Fibrosis: Pathophysiology
(4)
- DEC lung compliance (results in INC airway resistance on inhalation)
- INC elastic recoil
- INC fibroblasts result in INC collagen leading to fibrosis or scarring
- DEC diffusion capacity - gases cannot move across the membranes
Interstitial Pulmonary Fibrosis: Etiology
(4)
- Idiopathic (most common)
- Environmental exposure to inorganic dust, toxis gases, and certain drugs
- There may be a genetic factor
- Some connective tissue disorders are associated with IPF (ie RA)
- Hypothesized: Inflammation causes the fibrosis - abnormal wound repair
Interstitial Pulmonary Fibrosis:
Clinical Presentation
(6)
Inspection:
- Dyspnea
- INC RR + shallow breathing (tachypneic breathing)
- Dry, unproductive cough - irritation (do not need to expel anything)
- Clubbing
- Cynaosis
Later/ more progressed disease results in hypoxeamia - DEC O2 in blood & manifests in these S/S
- DEC chest expansion - bilaterally
Palpation:
- Tactile Fremitus: INC (more vibrations - thicker lung)
Percussion:
- Dull
Ascultation:
- Late fine dry inspiratory crackles - “velcro”
ABGs:
- DEC PaO2
- DEC PaCO2
INC RR, breathing out more frequently BUT do NOT get enough air in = poor diffusion of gas
CXR:
- Small contracted legs
- Raised diaphragm - bilaterally
- Diffuse reticular markings (mainly in lower lobes)
MESH appearance - fibrosis w/ air behind it
- High resolution CT is more commonly used to help assess the severity of IPE > Ground glass opacities is a key feature seen in IPF using HRCT
Sarcoidosis
Defintion & Patho & Etiology
A disease involving granuloma development (collection of inflammatory cells that form a lump) in the lungs, skin, lymph nodes, & other organs
Patho:
- Too complicated, do not need to know
Etiology
- Unknown
Atelectasis
Definition
Collapse of alveoli or lung tissue
May hve sub-segmental, segmental, or lobar distributions
Atelectasis:
Pathophysiology & Etiology
(6)
- Obstruction - ie mucus plug, trumor, foreign body
** Any alveoli DISTAL to a block will collapse - DEC nitrogen - helps keep open the alveoli
- DEC surfactant (INC surface tension)
- Compression - foregin substance, tumor - stuck close & collapse
- Hyperventilation
- Hypoventilation - breathing to shallow & not enough
Occur: post-op - not ventilating alveoli d/t incision sites
PNEUNOTHORAX always = atelectasis
Atelectasis: Clinical Presentation
(6)
Inspection:
- Dyspnea
- Cyanosis
- INC RR + shallow breathing (tachypneic breathing)
- IPSILATERAL trachael deviation - side of the atelectasis
Greater atelectasis = greater shift
Palpation:
- Tactile Fremitus: DEC (over a larger surface area & feeling vibrations over a more broad general area = feeling a lack of vibrations from that collapse area that has no lung tissue there (mostly empty space). Net affect is a DEC in tactile fremitus
- Chest wall excursion: DEC (on affected side)
Percussion:
- Dull (over atelectasis)
- Resonant - other areas will be normal
Auscultation:
- DEC BS or absent
- Dry inspiratory crackles (alveoli are opening - popping - open)
ABGs:
- DEC PaO2 - poor ventilation / good diffusion
CXR:
- Ipsilateral shift of metastinum
- INC density in area of atelectasis (whiteness)
- Elevated hemi-diaphragm (tenting)
Unilaterally less volume - diaphragm elevates
V/Q Complications
(2)
SHUNT
- Issue with ventilation - deoxygenated blood is passing by w/o being oxygenated
DEAD SPACE:
- Opposite of shunt - issues with perfusion (Q)
- O2 is available but gases are not getting exchanged
Shunt is perfusion of poorly ventilated alveoli. Physiologic dead space is ventilation of poor perfused alveoli.
Acute Respiratory Distress Syndrome
Description
An acute lung injury which is characterized by respiratory distress, severe hypoxemia, & increased permeability of the alveolar-capillary membrane
Clinical phenotype - not a disease itself
ARDS: Pathophysiology
(4)
- INC permeability of capillaries d/t injury. This will lead to edema in interstitial space & then into alveoli
Edema > interstitium > alveoli > lung - DEC surfactant production leading to INC alvelor surface tension causing DEC lung compliance
- V/Q mismatch > right to left shunt > aterial hypoxemia
Passing through w/o picking up O2
Good perfusion BUT poor ventilation (edema) - Rapid fibrosis in later disease progression = DEC lung compliance even after the ARDS resolves
ARDS: Etiology
(5)
- Shock (any type)
- Severe pneumonia
- Severe trauma
- Sepsis
- Aspiration (inhaled toxins)
ARDS: Clinical Presentation
(6)
Inspection:
- Severe dyspnea (often require mechanical ventilation at high PEEP)
PEEP = Positive Expiratory End Pressure: pressure to hold alveoli open & helps recruit more alveoli for gas exchange
- Cyanosis - hypoxaemia
- INC RR + shallow breathing (tachypneic breathing)
Palpation:
- Tactile Fremitus: INC (pulmonary edema + fibrosis)
Percussion:
- Dull
Auscultation:
- Inspiratory crackles, diffuse wheezes (obstruction)
ABGs:
- Severe DEC PaO2 & PaCO2 - hyperventilation (breathing so rapidly)
- Respiratory alkolosis
CXR:
- Patchy infiltrate in periphery of lungs (edema/fibrosis)
Pleural Diseases
(2)
- Pneumothorax
- Pleural Effusion
Pneumothorax
Description & Pathophysiology
An abnormal collection of air in the pleural space
Patho:
- Loss of negative pressure in pleural cavity causes expanded rib cage &/or collapsed lung
- Pressure of air on the outside of lung causes pressure into it & difficulty w/ expanding b/c of resistance = preventing alveoli from opening up > collapse
Pneumothorax: Sizes
(2) + Tx
- Small Pneumothorax
Air collects betwen the lung & chest wall - Large Pneumothorax
A lot of air collects & pushes on the lung & heart
Tracheal deviation
Tx of a large Pneumothorax:
- Trapped air is removed by using a chest tube
Pneumothorax: Etiology
(6)
- Trauma to chest wall
- Complication of invasive procedures - hole in pleural space
- Idiopathic
- Rupture of respiratory structures - Bullae (air pocket)
- Complication from mechanical ventilation (positive pressure) - to much (+) pressure can lead to rupture
- Infection of the pleura
Pneumothorax: Types
(3)
Spontaneous Pneumothorax:
- Develops suddenly d/t rupture in air containing structure
- Most common in young tall men
1. Primary (bleb/bullae rupture) vs
2. Secondary (secondary to another disease)
Traumatic Pneumothorax:
- D/t penetrating or non-penetrating (contusion) injury to chest wall
Tension Pneumothorax:
- Tear in pleura that acts as a one-way valve (only lets air out of the lungs)
- Air enters into pleural space during inhalation BUT does not leave during expiration
DANGEROUS - ACUTE LIFE-THREATENING SITUATION - MEDICAL EMERGENCY
Collapse of alveoli > atelectasis > mediastenal shift > progresses & gets worse > pressure on structures that bring blood back > DEC venous return > DECSV & CO > systemic HYPOtension > SHOCK (dangerous part)
Pneumothorax: Clinical Presentation
(6)
Inspection:
- Signs of respiratory distress
- Dyspnea
- INC RR
- Chest pain HALLMARK** Not seen in other conditions
- Dry cough (irritation of pleural receptors)
Palpation:
- Tactile Fremitus: DEC (d/t air trapping)
Percussion:
- Hyper-resonant (d/t air trapping)
Ascultation:
- DEC or absent BS (depending on severity)
ABGs:
- DEC PaO2
CXR:
- Blackened area around the lungs
- Flattened hemi-diaphragm (ipsilateral to pneumothorax - UNILATERAL)
Pleural Effusion
Description & Pathophysiology & Etiology
An abnormal collection of fluid in pleural space
Patho:
- INC production OR DEC clearance of fluids
Etiology:
- Secondary to infection, cancer, or disease
Ex. CHF, liver disease, kidney disease, pneumonia, pulmonary embolism, TB, trauma
Pleural Effusion: Types
(2)
Exudative:
- INC permeability of the pleural space leading to INC fluid, proteins, WBC, & immune cells into the pleural space
Should NOT be able to cross the barrier (too large) but d/t permability allows them through
- Fluid is cloudy (opaque)
- Caused by inflammation, infection, or cancer
Transudative
- INC hydrostatic pressure in the pleural capillaries (ie CHF)
- Fluid is clear & has very few proteins
HIGH -> LOW pressure (LOW = the interstitual space & pleura)
Pleural Effusion: Clinical Presentation
(6)
Inspection:
- May have dyspnea (if large effusion causes compressive atelectasis > making it difficult for alveoli to open)
- INC RR
- May have chest pain (especially with DB & coughing - expansion of lungs)
- Dry cough
Palpation:
- Tactile Fremitus: DEC (over fluid) & INC just above the effusion where the tissue is compressed (dense/thicker tissue)
- Chest wall excursion: DEC on side of effusion (UNILATERAL)
Percussion:
- Dull - over effusion area
Auscultation:
- DEC or absent BS over effusion
- Pleural friction rub - exclusive to pleural effusions
fresh snow or shaved head (fuzzy)
ABGs:
- DEC PaO2
- DEC PaCO2 - hyperventilation
CXR:
- White in areas with INC fluid in the pleural space
- Contralateral trachael deviation
Effusion causes pressure - lung is compressed which causes more pressure = deviates away
- May see elevated hemi-diaphragm on the side of the pleural effusion
Atelectasis - lung is not expanding - accumulation of fluid at bottom d/t gravity - needs to have a lot of fluid in order to travel up & causes a deviation
More commonly UNI-lateral but can be BI-lateral
Chest pain for this condition is a differential detail
Chest Wall Deformities:
Bony Deformities
(6)
Various deformities of the bony structures of the body
- Ankylosing spondylitis - fusing = DEC chest wall expansion (DEC compliance)
- Congenital deformities
- Kyphosis
- Kyphoscoliosis
- Pectus Carinatim - convex - Pigeon
- Pectus Excavatum - concave - Funnel
Chest Wall Deformities:
Bony Deformities - Etiology
(3)
- Idiopathic
- Neuromuscular disease
- Congenital
Chest Wall Deformities:
Bony Deformities -
Clinical Presentation
(6)
Inspection:
- Dyspnea
- SOBOE
- Abnormal thorax shape
Palpation:
- Tactile Femitus: DEC - less air = less ventilated lung
- Chest wall excursion: DEC
Percussion:
- Normal
Auscultation:
- Normal
ABGs:
- DEC PaO2
- DEC PaCO2
- There is an INC in WOB
CXR:
- Dependent on bony deformity.
- Possible atelectasis in lower lobes b/c of inability to expand lungs completely
Neuromuscular Disorders
(8)
Nerve, NM junction or muscle - all can affect the muscles or mechanics of respiration
- ALS
- Gullian-Barre Syndrome
- Multiple Sclerosis
- Muscular Dystrophy
- Myasthenia Gravis
- Parkinson’s Disease
*Looks like it doesn’t fit here, no probs w/ mm itself (no weakness) BUT: anxiety, side effects of medication, stooped/kyphotic posture, & respiratory dyskinesia (refers to irregular & rapid breathing - side effect of levadopa) - Poliomyelitis
- SCI
Muscles of Ventilation: Diaphragm
(3)
Primary mm of ventilation
Innervation: C3-4-5 (keeps the diaphragm alive)
- C4 is vital (w/o = mechanical ventilation)
Dependent on the intercostal & abdominal mm
- Diaphragm does not work in isolation **
- Mechanical disadvantage w/o abdominals
- May need abdominal binder when doing activities that require INC O2
Muscles of Ventilation: Intercostals
(4)
Innervation: T1-T12
Acts to stabilize the rib cage
- INTERNAL intercostals = active exhalation
Difficulty with coughing - EXTERNAL intercostal = inhalation (quiet & forceful)
Muscles of Ventilation: Abdominals
(3)
Innervation: T6-L1
Stabilize inferior border of rib cage
INC intra-abdominal pressure for strong effective cough
Accessory Muscles of Ventilation
6+2
- Erector Spinae
- Pectoralis Muscles
- Serratus Anterior
- Scalenes
- SCM
- Trapezius
- Lats
- QL
7-8 - may also be considered key mm of ventilation
