Pathopharm II : Restrictive Lung Disorder

Restrictive Lung Disorder

Intrinsic

The lung tissue itself is damaged/stiffIPF, pneumoconiosis, sarcoidosis, hypersensitivity pneumonitis

Extrinsic

Something outside the lung prevents it from expandingPleural disorders, chest-wall disorders, neuromuscular weakness, severe obesity

TLC

he TOTAL amount of air your lungs can hold after you take the biggest breath possible.— Example: IPF → lungs become stiff → can't expand fully → ↓

FVC 

the amount of air you can FORCEFULLY blow out after taking the deepest breath possible. In restrictive disease ↓

FEV₁

air expelled in the first 1 second

FEV₁/FVC

air blown out in first second ÷ total forced air blown out- normal/elevated in restrictive and lower in obstructive

Idiopathic Pulmonary Fibrosis

progressive, irreversible scarring of the lungs for unknown reason

Pathophysiology of IPF

Alveolar injury
↓
Abnormal healing
↓
Fibrosis/scarring
↓
Lungs become stiff
↓
Lungs can't expand normally
↓
Gas exchange becomes impaired
↓
Less oxygen gets into the blood
↓
Worsening hypoxemia

IPF findings

Shortness of breath, chronic cough, fatigue, weightloss

IPF diagnosis

CXR, CT, PFT, lung biopsy

Goal of IPF treatment

• Pirfenidone

• Nintedanib

• Oxygen

• Pulmonary rehabilitation

• Lung transplant for severe disease

Nintedanib Indc.

IPF- Blocks fibrosis pathways

Nintedanib ADR and N Cons.

Diarrhea, nausea, ↑ LFTs ; monitor LFT and manage diarrhea

Pirfenidone Indc

Reduces fibrosis processes

Pirfenidone Indc.

IPF-Reduces processes involved in fibrosis → slows decline in lung function.

Pirfenidone ADR and N Cons.

GI upset, photosensitivity, ↑ liver enzymes : Monitor liver function + teach sun protection.

Nerandomilast Indc.

IPF- PDE4 inhibitor → slows decline in lung function.

Nerandomilast ADR and N Cons.

Diarrhea, ↓ appetite, weight loss ; Monitor/manage diarrhea + monitor for mood changes.

Pneumoconiosis

lung disease caused by inhaling workplace dust- lung

inflammation → nodules and/or scarring

Pneumoconiosis - Pahtophysiology

A person repeatedly inhales dust at work.

⬇

The dust causes lung inflammation.

⬇

Over time, this can produce nodules and/or scarring.

⬇

The scarring can become irreversible.

⬇

Eventually, the patient can develop shortness of breath and chronic cough.

type of dust determines the type of pneumoconiosis

Asbestosis—>Asbestos

Silicosis—>Silica

Coal workers' pneumoconiosis—>Coal dust

Pneumoconiosis symptoms

May be absent early;

later shortness of breath and chronic cough

Pneumoconiosis diag.and trtm

Exposure history, chest X-ray or CT,

and PFTs : top further exposure; manage

symptoms with supportive care such as oxygen

or pulmonary rehabilitation when needed

Sarcoidosis

an inflammatory disease where the immune system forms granulomas in different organs (Type IV cell mediated inflammation→ non-caseeating granulomas- granulomas affect many different organs (lungs, chest lymph nodes,eyes, skin)

Granulomas

organized collection of immune cells formed around something the body is trying to contain.

Noncasseating granulomas

does not have dead cheese like tissue in middle

sarcoidosis symptoms

If granulomas develop in the lungs, they can interfere with normal lung function→

Dry cough

• Dyspnea

• Fatigue. some patients have no symptoms

sarcoidosis diagnosis

Chest X-ray / CT

Looks for changes in the lungs/chest.

PFTs

Evaluate lung function.

Biopsy

Shows the characteristic:

NONCASEATING GRANULOMAS

⭐ Biopsy → noncaseating granulomas = major diagnostic clue

scardosis trtm

Mild disease

Observation

Because sarcoidosis can sometimes resolve on its own.

More significant disease

Corticosteroids

→ reduce inflammation.

If additional treatment is needed

Other immunosuppressive drugs

Hypersensitivity Pneumonitis patho

Immune reaction to

repeatedly inhaled substances → lung

inflammation; ongoing exposure may

cause fibrosis

Hypersensitivity Pneumonitis triggers

Bird feathers/droppings, mold, and hay or

grain dust

Hypersensitivity Pneumonitis Symptoms and diagnosis

Dry cough, shortness of breath, fatigue; fever and chills may occur after

exposure : Exposure history, chest CT, and

PFTs

Hypersensitivity Pneumonitis trtm. n cons.

Avoid the trigger; corticosteroids when indicated and oxygen

if blood oxygen is low and Finding and avoiding the causative exposure is the priority

Pneumothorax patho

Air in the pleural space → partial or

complete lung collapse ;Air in the pleural space → partial or

complete lung collapse

Spontaneous

air leaks from the lung without injury

Pneumothorax: Traumatic

air or blood enters after injury/medical

procedure-Tension (air enters but cannot escape → rising pressure

compresses the lung and major blood vessels → ↓ blood

return to the heart and ↓ cardiac output

Pneumothorax: symptoms and diag.

Sudden sharp chest pain, shortness of breath, ↓

breath sounds on the affected side, ↑ RR/HR : Chest X-ray; CT or ultrasound if needed

Pneumothorax: trtm and N cons

Observation if small and stable

• Needle aspiration or chest tube if needed

• Surgery for selected recurrent case : Tension pneumothorax is an emergency—

respiratory distress and hypotension require immediate

decompression; do not wait for imaging.

Pleural Effusion

Fluid in the pleural space

Pleural Effusion: Transudate

imbalance in pressure that pushes fluid out of the blood vessels and into the pleural space (causes: HF, cirrhosis )

Pleural Effusion: exudate

capillaries become leaky, allowing fluid to escape into the pleural space. (causes: Pneumonia, Cancer, Pulmonary embolism (PE))

and diag. symptoms

Chest pain, shortness of breath, dry

cough; fever may occur with infection. : Dull percussion, ↓ tactile fremitus, asymmetric expansion, ↓ breath sounds; sometimes egophony or a

pleural rub —-.: CXR or ultrasound; thoracentesis for fluid

analysis when indicated.

Pleural Effusion: trtm and n cons.

Treat the cause (HF, PE, ect)- Thoracentesis, chest tube, or pleurodesis when

indicated : FLUID = DULL → dullness to percussion +

decreased breath sounds on the affected side.

Pleuritis patho

Inflammation of the pleura (lung lining).

Inflamed pleural layers rub during

breathing → pain.

Pleuritis: cause

Viral infection, pneumonia, cancer, PE, autoimmune

disease.

Pleuritis: symptoms and diag.

Sharp chest pain worsened by breathing or

coughing; possible fever or dry cough. Pleural friction rub : Clinical assessment, CXR or CT; thoracentesis if an

effusion needs evaluation

Pleuritis: trm and n cons

Pain control, anti-inflammatories, treat the underlying

cause : Sharp pain with inspiration + pleural friction

rub suggests pleuritis

Chest-Wall Restrictive Disorders -Chest-Wall Abnormalities

The chest wall cannot expand

fully → ↓ lung volumes. ex. Kyphoscoliosis

Kyphoscoliosis

spinal and rib-cage curvature

that restricts chest movement.

Kyphoscoliosis: patho

↓ chest-wall compliance → ↓ lung expansion

→ possible hypoventilation.

Kyphoscoliosis : symp

Dyspnea, fatigue, exercise intolerance.

• Spirometry : ↓ TLC and ↓ FVC; FEV₁/FVC normal or ↑.

Kyphoscoliosis :Severe disease:

Hypoxemia, hypercapnia, or pulmonary hypertension.

Kyphoscoliosis : trtm and n cons.

Manage the underlying condition

• Pulmonary rehabilitation, oxygen, or ventilatory support

when indicated : The chest wall limits expansion, even when lung

tissue is normal.

Neuromuscular Restrictive Disorders

Respiratory muscle weakness → inadequate lung

expansion. - Examples: Myasthenia gravis, ALS, muscular dystrophy.

Neuromuscular Restrictive Disorders : patho

Weak diaphragm/intercostals → ↓ vital

capacity and ventilation; weak cough → retained

secretions and ↑ infection risk.

Neuromuscular Restrictive Disorders : symp

Dyspnea, fatigue, weak cough, orthopnea. Severe weakness: Hypoventilation → respiratory failure

Neuromuscular Restrictive Disorders : trtm and n cons.

Treat the underlying disorder

Provide cough assistance and ventilatory support as

needed. —Worsening respiratory muscle weakness

can rapidly become an emergency.

Obesity Related Restrictive Lung Disease: patho

Excess thoracic and abdominal adiposity

limits chest-wall and diaphragmatic

movement. Mechanical restriction → ↓ lung expansion

and lung volumes

Obesity Related Restrictive Lung Disease: symp

Dyspnea and exercise intolerance.

Obesity Related Restrictive Lung Disease: trtm and n cons.

Weight reduction, Management of the underlying condition. —The chest wall limits expansion; the lung tissue itself may be normal.

Acute Respiratory Distress Syndrome (ARDS): Acute inflammatory lung injury

severe hypoxemic respiratory failure

Acute inflammatory lung injury: patho and causes

Sepsis, severe shock, pneumonia, aspiration, major

trauma.

Inflammation damages the alveolar-capillary membrane → protein-

rich fluid leaks into alveoli (noncardiogenic pulmonary edema).

Fluid disrupts surfactant → alveolar collapse → stiff lungs

(↓ compliance) and poor oxygen transfer (Collapsed/fluid-filled alveoli can't transfer oxygen well)

Acute inflammatory lung injury: symp and diag

Rapid-onset dyspnea, tachypnea, and hypoxemia.

- Hypoxemia difficult to correct + bilateral lung opacities, not explained by heart failure alone.

Acute inflammatory lung injury: trtm and n cons.

Treat the cause (e.g., antibiotics for infection) and provide oxygen.

If ventilated: small tidal volumes, limited pressure, and positive

end-expiratory pressure (PEEP); prone positioning when indicated.

•Use conservative fluid management when appropriate

.—-fluid-filled, collapsed alveoli → stiff lungs + severe hypoxemia; support oxygenation while treating the caus

Pulmonary Hypertension patho

↑ pressure in the pulmonary circulation

— ↑ pulmonary vascular resistance

and/or ↑ pulmonary vascular pressure → ↑ RV

workload → RV hypertrophy/dilation → right-sided

HF