Lung III - Obstructive + Restrictive Flashcards
Compare and Contrast
- obstructive vs restrictive diseases
- flow spirometry results
Obstructive - AIRWAY disease - think resistance
- airway inflammation, mucous, BC, narrowing, resistance
- inflow problem, expiratory obstruction
- air trapping - pulmonary hyperinflation leads to increased TVC
- slow exhale, and not completely - air trapping
Restrictive - parenchymal disease - think compliance
- FIBROSIS, Compliance DECREASED - HIGH RECOIL
- elasticity lost, compliance lost - Recoil high
- Cant expand properly - FEV1 volume lowered to begin with
O vs R Spirometry
- FEV1: Both decreased
- FVC: Both decreased
- Ratio: FEV1 decreased way more for COPD hence COPD ratio less than 0.8
- TLC: Increased vs Decreased - ONLY TEST DIFFERENCE
Elastic Recoil and Compliance
Inverse: low compliance high recoil;
Restrictive disease
- fibrosis, higher elastic recoil, lower compliance - stiff lungs;
- edema, higher surface tension, lower compliance
Obstructive disease - destruction of elastic tissues, lower elastic recoil, higher compliance - harder to exhale
Examples of O and R
O:
COPD, Asthma, Bronchiectasis, Emphysema
R:
- CHEST WALL
- Parenchymal lung disease, Lung Fibrosis, Edema
Asthma pathology features, pathophysiology,
What areas does the treatment target
Bronchioles chronic inflammation
Bronchospasm
Excessive mucous production, smooth muscle hyperactivity, hypertrophy, mucosal edema, inflammatory inflitrates
Allergy: IgE, Eosinophils, Mast Cells
- over time remodelling
- type II respiratory failure
Preventive: chronic inflammation
Therapeutic: bronchospasm
Contrast COPD and Asthma [2]
COPD is mostly chronic smokers lol
COPD vs Asthma: COPD is irreversible, progressive
- COPD can be stable but predispose to illnesses which deteriorates it;
- Asthma gets better. Symptoms can come and go, and you may be symptom-free for a long time. With COPD, symptoms are constant and get worse over time, even with treatment.
Whats COPD
group of lung diseases
- emphysema - alveoli disease
- bronchitis and bronchiolitis - w bronchitis more mucus secretion, bronchiolitis more inflammation and scarring
Whats emphysema and link to lung disease
Pathogenesis
1/3 of COPD lol - Top cause is irritants, SMOKING
- dilatation of alveolar air spaces w destruction of tissues WO SCARRING
- loss of elastic recoil - high compliance - COPD
- alveoli and tubes collapse - air trapping - obstruction
Pathogenesis:
- Congenital A1Antitrypsin deficiency - then protease destroys cells; exacerbate damage by smoking; A1AT supposed to inhibit protease from neutrophils
- protease damages alveolar wall - emphysema
- Otherwise Smoking also inhibits such inhibitors, also contain free radicals for tissue damage
A1AD in liver:
- cause of Cirrhosis, Jaundice due to improper secretion, accumulation
- normally A1AT is produced in LIVER!
Pulmonary emphysema, more usually called emphysema, is characterised by air-filled cavities or spaces, (pneumatoses) in the lung, that can vary in size and may be very large. The spaces are caused by the breakdown of the walls of the alveoli and they replace the spongy lung parenchyma. This reduces the total alveolar surface available for gas exchange leading to a reduction in oxygen supply for the blood.[2] Emphysema usually affects the middle aged or older population. This is because the disease takes time to develop with the effects of smoking, and other risk factors. Alpha-1 antitrypsin deficiency is a genetic risk factor that may lead to the condition presenting earlier.[3]
COPD Respiratory Failure Phenotypes
Blue Bloaters - Cyanosis
- CHRONIC BRONCHITIS is primary problem while capillary ok
- V/Q mismatched ventilation problem
- hypoxia, hypercapnia - Type II RF
- Hypoxic PV, the RHF;
- Brainstem reset tolerance of hypoxemia and hypercapnia
Pink Puffers - TYPE I Respiratory Failure
- EMPHYSEMA is primary problem
- V/Q, perfusion low - hyperventilation to compensate - Type I RF - pink face
Treatment of COPD WRT 2 phenotypes
- what are the phenotypes caused by
All: treat infections, Bronchodilators,
BUT Blue Bloaters: Breathing reflex not triggered by hypercapnia anymore - is by hypoxia - so dont give High O2 - which reduces rate of ventilation - Monitor
Blue Bloater - think chronic bronchitis,
Pink Puffer - Emphysema
Restrictive lung disease features
- Edema (acute), Fibrosis (chronic)
- predominantly interstitium inflammation pathology
- reduced compliance
- thickened walls reduces exchange
ARDS
Description
Causes
Acute and Chronic histologies
Acute respiratory distress syndrome - note is Restrictive
- diffuse alveolar and capillary damage
- causes like sepsis, trauma, burns, toxic fumes
Acute - damage then interstitial edema, fibrin, protein exudates, necrotic cells - hyaline membranes into the alveoli
- the membrane impairs gas exchange - hypoxemia
- 70% DEATH in acute phase
Chronic
- Regeneration of alveolar cells, inflammation - fibrosis
- marked interstitial fibrosis - Honeycomb lungs; hyaline membrane is organized
- – HONEYCOMB LUNGS: cystic space w fibrous tissue
Common between NRDS and ARDS
NRDS - surfactant insufficiency - surface tension high, alveolar collapse, endothelium damage - hyaline membrane formation
- NRDS also called Hyaline membrane disease
ARDS - damage - edema, inflammation - hyaline membrane formation
Whats honeycomb lungs
Chronic pulmonary fibrosis end-stage
- WIDESPREAD FIBROSIS w cystic space
- found in ARDS
What can bird dropping cause
Type III hypersensitivity @ alveoli, pneumonitis
- Hypersensitivity pneumonitis
- chronic leads to Type IV
Bird fancier’s lung (BFL) is a type of hypersensitivity pneumonitis
Whats pneumoconiosis
Causes
Pathology
Not allergy, is by Inorganic material
- dust, silica, asbestosis, coal
- inflammation then fibrosis
- note also an interstitial disease
aka Occupational lung disease
- Koni - refers to dust
