Diseases & Conditions Affecting the Respiratory System

What are the types of conditions that can impact respiration?

• Obstructive Lung Disease

• Restrictive Lung Disorders

• Neuromuscular Diseases & Conditions

• Cardiopulmonary

• Sepsis

• Adult Respiratory Distress Syndromes

(Obstructive Lung Disease) What is Chronic Obstructive Lung Disease (COPD)?

• progressive disease

• irreversible destruction of lung tissue

• Patient has chronic feeling of “I can’t breathe”

• Requires supplemental oxygen via nasal cannula

• Eventually may require tracheostomy +/- mechanical ventilation

(Obstructive Lung Disease) What are the 2 subtypes of obstructive lung disease?

• Chronic Bronchitis

• Emphysema

(Stages of COPD) Stage 1:

• Mild symptoms: some dyspnea (shortness of breath)

• Most people do not realize that they have the disease

• Pulmonary Function Tests (PFTs) = 80% of predicted

(Stages of COPD) Stage 2:

• Moderate SOB w/ exertion/exercise

• First time seeing medical care for chronic symptoms

• May see occasional exacerbation

• PFT’s = 50-80% of predicted

(Stages of COPD) Stage 3:

• Severe symptoms – increased SOB, may have a cough, excessive mucous/sputum, or both, or neither

• Exercise is difficult

• Fatigue

• QOL suffers

• Exacerbations more frequent, but, not life threatening

• PFTs = 30-50% of predicted

(Stages of COPD) Stage 4:

• Severest symptoms

• Trouble breathing may be life threatening at times, “Exacerbations”

• Poor QOL due to SOB

• PFTs = less than 30% predicted

Emphysema:

• destruction of alveoli walls, forming larger, gaping, irregular air spaces

• Loss of alveolar surface area → less O2 enters the blood stream

• Alveoli lose elasticity

• Overtime, alveolar sac is destroyed & bronchioles collapse

What can occur over time with emphysema?

• Hyperinflation needed to get oxygen into blood; but, less efficient, & air gets trapped behind collapsed airways

• Inhalation – use accessory muscles

• Exhalation – difficult to expel CO2 → “Pink Puffer” pattern

• Barrel Chested

• Blood Gas – decreased O2, normal-ish CO2

(Restrictive Lung Disorders) Chronic Hypo-inflation:

• Muscle movement AND mechanical factors

• Lung tissue (bronchi & alveoli) may or may not be “ok”

(Restrictive Lung Disorders) Decreased lung compliance/elasticity:

• Stiffens the lungs & chest wall → inflation difficult/lung resistant to inflation → reduced lung volumes → decreased ventilation

(Restrictive Lung Disorders) Common conditions/processes:

• Acute disease can lead to chronic conditions

  • PNA (inflammation changes)

• Adult Respiratory Distress Syndrome

(Restrictive Lung Disorders) What are connective tissue disorders?

• tissue loss & fibrotic changes

  • Scleroderma → autoimmune

  • Lupus → autoimmune

  • Interstitial fibrosis → inflammatory

(Restrictive Lung Disorders) Skeletal issues:

• Scoliosis

• Arthritis

What are neuromuscular diseases that can impact respiration?

• ALS

• MS

• MD

• Guillain-Barre syndrome

• CVA

• Poliomyelitis

• Spinal cord injury

(Neuromuscular Diseases) ALS:

• Corticospinal → loss of muscle strength, diaphragm paralysis

• Corticobulbar → dysphagia & dystussia → aspiration PNA

• Tracheostomy + mechanical ventilation needed

(Neuromuscular Diseases) MS:

• Demyelinating process → decreased muscle strength → diaphragm paresis

• Demyelinating process → dysphagia & dystussia → aspiration PNA

(Neuromuscular Diseases) Muscular Dystrophy (MD):

• progressive muscular weakness common in all striated muscles, heart, & diaphragm

• may have dysfunction in brainstem CPG

• chronic hypoinflation → atelactasis, impaired mucociliary transport, PNA

• Dysphagia → aspiration PNA (Duchenne’s)

(Neuromuscular Diseases) Guillain-Barre syndrome:

• viral infection, immunization response, or other

• starts at the extremities & progresses medially, then superiorly

• acute respiratory failure requiring mechanical ventilation

• may or may not involve swallowing, if it does, then aspiration PNA can also factor into lung disease

• can improve back to ba

(Neuromuscular Diseases) Stroke (CVA):

• Brainstem – direct effect; trach +/- vent typically needed

  • (dysphagia, dystussia, dysarthria/anarthria also present & can give secondary effect to respiratory issues

• Cortical – peripheral effect due to decreased muscle tone & body posture

(Neuromuscular Diseases) Poliomyelitis:

• Viral

• Severe muscle weakness w/ respiratory failure requiring mechanical ventilation (“Iron lung”)

  • brainstem damage to CPG

  • spinal cord nerve damage (anterior horn cells)

• Post-polio syndrome → respiratory insufficiency, dysphagia

  • it sounds like…

(Neuromuscular Diseases) Spinal Cord Injury:

• Damage to the Corticospinal Tract

• Can occur anywhere along the spinal cord

• Where it occurs dictates what type of function the person will have. At the point of injury, all function below is lost; function above remains intact. The higher up the injury, the less function.

(Neuromuscular Diseases) What would a complete spinal cord injury result in?

• sensory AND motor function lost

(Neuromuscular Diseases) What would an incomplete spinal cord injury result in?

• sensory OR motor function lost

(Neuromuscular Diseases) Cervical injury:

• quadriplegia/tetraplegia

(Neuromuscular Diseases) Thoracic injury:

• paraplegia (paralysis that affects the lower body, typically from the waist down)

(Neuromuscular Diseases) Lumbar injury:

• paraplegia; loss of bowel & bladder, excual dysfunction

(Neuromuscular Diseases) Sacral injury:

• some hip & leg weakness, bowel/bladder dysfunction, sexual dysfunction

Where can spinal cord injury & impaired respiration occur in?

• can occur from any trauma from Cervical to Thoracic spinal cord

Cervical:

• decreased PFT’s in all capacities

  • high cervical injury (C1-C4)

  • low cervical injury (C5-C8)

High Cervical Injury (C1-C4):

• Diaphragm paralysis due to lost phrenic nerve inputs

• Traditionally, mechanical ventilation needed

• Research: neuroplasticity of phrenic nerve system & improved respiration; animal models have come off of ventilator support

Low Cervical Injury (C5-C8):

• acute phase, may need temporary ventilator support

• over time, do not

Thoracic:

• restricted lung movements due to trunk weakness & restricted rib cage mobility

What are cardiopulmonary conditions?

• Can involve either the Left, Right, or both ventricles of the heart

  • Pulmonary Edema

  • Congestive Heart Failure (CHF)

  • Cor pulmonale

Pulmonary Edema:

• impairment in the Left ventricle results in increased pressure in the pulmonary vein. Pressure leads to fluid leaving the blood & settling in the alveoli. Ultimately, causing edema in the lung & blocking gas exchange

Congestive Heart Failure (CHF):

• Heart cannot pump out sufficient blood volume & fluid fills up the lungs (Typically, due to heart disease)

  • Right side issue can develop due to Left side failure

  • Then, excess fluid can lead to pressure increase in the pulmonary artery. Increased arterial pressure can lead to Right ventricular hypertension.

Cor pulmonale:

• variation where ventricular hypertension happens in some w/ COPD

  • lung disease led to heart disease

(Cardiopulmonary Conditions) Heart Failure:

• Ventricular Assist Device (VAD)

• L-VAD → most common

Adult Respiratory Distress Syndrome (ARDS):

• Acute/Adult (ARDS) – Restrictive Lung Syndrome

• umbrella term referring to acute onset impairment of oxygen transfer at the alveolar capillary membrane

What is the pathophysiology of ARDS?

• Fluid leaks into alveoli

• Loss of surfactant

• Severe atelectasis (collapse of alveoli)

What does ARDS result in?

• Hypoxemia: oxygen deficiency in the blood

• Decreased pulmonary compliance

• CO2 retention

• Hypoxia: lack of oxygen in the tissue

  • Increased Work of Breathing (WOB) → Respiratory muscle fatigue → Respiratory muscle failure

(RDS) What is SARS?

• Severe Acute Respiratory Syndrome (SARS)

• Identified in 2003

• Coronavirus, contagious, about 8000 cases wordwise, with about 75- deaths (~10%)

• Pneumonia-like presentation with fever

• No new cases since 2004

(RDS) What is MERS?

• Identified in 2012 in Saudi Arabia/Arabian Peninsula

  • currently in 27 countries

  • Largest outbreak in 2015 in Korea

• United States: 2 cases, in 2014

  • No new cases since then (CDC, 2019)

• New Coronavirus; different than SARS

  • more contagious & more deadly

    • 2029 cases reported; 704 deaths

• Pneumonia like presentation with fever

• Severe Acute Respiratory Syndrome-2

• Worldwide Pandemic→Now Endemic

  • A pandemic is defined as outbreaks on three or more continents simultaneously. We have passed the pandemic phase, it's safe to say, and entered what we call an endemic phase, meaning SARS-CoV-2, the virus that causes the disease COVID-19, will stay in humans forevermore.

• Effects lungs/respiratory system and many other organs and body systems

Legionnaires’ Disease (Pontiac Fever):

• More Severe “Atypical” Pneumonia

• First identified in 1976

  • American Legion Convention

• 8-18K/year new cases in USA

  • Illinois, 2015: 200+ Quincy VA Skilled Nursing Facility – Illinois 2023: 300+ cases; Prisons and Public Gyms

• Cause: Legionella Bacteria

  • Contaminated water—inhaled or aspirated

• Results in:

  • SOB, Fever, Death

  • 1/10 die: Older, Smokers, Lung disease, immune-compromised