Week 4: Pulmonary Conditions

SOB (dyspnea) is a common symptom

of cardiovascular or pulmonary condition

How does the brain control ventilation?

Through a feedforward and feedback mechanism.

What is feedforward in the context of ventilation?

An anticipatory signal where the brain estimates required ventilation based on joint motion or anxiety.

output of feedforward signals

-motor activity to mm of inspiration

What does feedback in ventilation depend on?

How well oxygen is delivered to muscles, CO2 removal, and pH maintenance.

What can cause a mismatch of afferent and efferent signals?

Malfunctioning brain leading to anxiety and sense of doom.

What is hypoxic hypoxia?

A condition where there is not enough O2 in the blood and too much CO2.

What is ischemic hypoxia?

A condition where an area of the heart is not getting enough blood, typical of a heart attack., stroke and PVD

cardiac pump failure

What is anemic hypoxia?

A condition where blood's oxygen-carrying capacity is low, also known as anemia.

What is the leading cause of morbidity and mortality in adults in Western civilization?

Ischemic hypoxia.

3rd leading cause of M&M

hypoxic hypoxia

Much of the M&M of cancer and other condition/injury is manifested as damage to the

CVP systems

Breathing Disorders causes

1. Damage to the breathing control mechanisms within the brain stem

2. Restrictive condition

3. Obstructive condition

. Restrictive condition

Difficulty in generating the △P required to create airflow

Cannot inhale well

Obstructive condition

Difficulty in generating airflow for a given △P between the atmosphere and alveoli

Cannot exhale well

Damage to Breathing Control Mechanisms

Caused by Chronic hypoventilation with CO2 retention =hypercapnea

CVA or Head injury

NM conditions

Central sleep apnea

CVA or Head injury brainstem injury

malfunctions central respiratory drive

NM conditions and breathing control mechanisms

Rapid shallow breathing secondary to muscle weakness or abnormal motor neuron function

Central drive is maintained but alveolar ventilation is not

Central sleep apnea

Brain doesn't send proper signals to muscles of inspiration during sleeping in central sleep apnea

Restrictive Disorders

Requires a greater effort to move chest to breathe regardless of strength of muscle

Normal strength, but too stiff chest wall

Normal stiffness, but too weak muscles or damaged nerves

spriometry in restrictive diseases

volumes are reduced in restrictive condition

What are the two basic causes of obstructive disorders?

Increased airway resistance and decreased elastic recoil.

FRC

functional residual capacity

FRC in obstructive disorders

Abnormally high

CF results in obstructive dz; either

bronchiectasis or chronic bronchitis

Obstructive disorders are characterized by

FRC, marked increase in A-P diameter of chest (barrel-chested), and slow expiration

COLD=Chronic Obstructive Lung Disorder

Any disorder that blocks bronchial airflow

Generally permanent or progresses that results in bronchitis and emphysema

What is the Equal Pressure Point (EPP)?

The point in the airway where outside compressive pressure equals inside elastic pressure.

What happens to the EPP in obstructive diseases?

It moves distally into smaller airways, making them more susceptible to collapse.

In healthy lungs, the EPP occurs in

larger airways with cartilaginous rings

During emphysema the weakened elastic recoil shifts the EPP towards

the smaller lungs which causes narrowing and collapse and difficulty breathing out

The EPP is affected by:

Anatomy/shape

Elastic recoil

What is the effect of emphysema on elastic recoil?

It primarily causes a loss of elastic recoil, making expiration difficult.

In obstructive condition, Loss of pressure moving air through obstruction moves the equal pressure point

distally

Lung collapse:

When the pressure outside of the lung is equal to or greater than the inside.

Four Conditions of COPD (ABCE)

Asthma

Bronchiectasis

Chronic Bronchitis

Emphysema: weakened and collapsed air sacs with excess mucus

What is the difference between restrictive and obstructive disorders?

Restrictive disorders involve trouble getting air into the lungs, while obstructive disorders involve trouble getting air out.

What are some examples of restrictive conditions?

Lung fibrosis, sarcoidosis, obesity, scoliosis, and neuromuscular conditions.

What is the typical breathing pattern in obstructive disorders?

Long, slow breathing is more efficient due to increased airway resistance.

What role does the brainstem play in breathing control?

It regulates central respiratory drive; damage can lead to conditions like hypercapnea.

What is the significance of chronic hypoventilation?

It can lead to CO2 retention and hypercapnea.

What is the impact of neuromuscular conditions on breathing?

They can cause rapid shallow breathing due to muscle weakness or abnormal motor neuron function.

What is the relationship between COPD and airway resistance?

Increased airway resistance makes it harder to exhale air.

What is the effect of forced expiration in obstructive conditions?

It becomes less effective as small airways collapse, trapping air and mucus.

What is the role of pursed lip breathing in COPD?

It can help equalize pressure and assist with exhaling air.

What is the consequence of lung collapse?

It occurs when the pressure outside the lung is equal to or greater than the inside.

What are common conditions associated with obstructive disorders?

COPD and asthma.

What is the main cause of dyspnea in COPD?

Ventilation problems due to airway obstruction.

COPD almost exclusively caused by

smoking

Small airways involved first in COPD

Because of the large number of airways in parallel, early changes in resistance not noticeable without exertion, then blamed on aging, lack of exercise, etc

What is the relationship between cancer metastasis and the lungs?

One of the main sites for cancer metastasis is the lungs.

What does COPD stand for?

Chronic Obstructive Pulmonary Disease

What are the two main conditions that comprise COPD?

Emphysema and chronic bronchitis

What is the primary cause of COPD?

Almost exclusively caused by smoking

What characterizes emphysema?

Weakened and collapsed air sacs with excess mucus

What is the typical onset of COPD symptoms?

Usually insidious, but perceived as acute by many patients

What happens to small airways in COPD?

They are involved first, leading to increased resistance and decreased respiratory reserve.

How does smoking affect lung cancer risk?

It increases the risk 15-30 times more likely to develop lung cancers.

Smoking disrupts the balance of

proteases(break down tissue) and anti-proteases(protect tissue) by inactivating the antiproteaseases

Location of damage indicates type of COPD

Emphysema- destroys connective tissue in the alveoli (distal to the bronchioles)

Bronchitis-goblet cells get hyperplasia in the bronchioles which leads to an increase in number d/t inflammation of the bronchioles

Emphysema

Abnormal, permanent enlargement of air spaces distal to bronchioles with destruction of their walls primarily in the alveolar walls

When the elastic fibers in alveolar walls destroyed

Decreased elasticity

Increased compliance (alveoli fill with rather low pressure)

At first the lungs increase in size until recoil sufficient to drive air out

Eventually the lungs get too stretched out and get similar to passive insufficiency

S&S of Emphysema

Hyperinflated/Barrel chest

Thin/Emaciated

Muscle wasting

Non productive or no coughs at all

Depression and poor sleep quality

Hypertrophied SCM & scalenes

Prolonged expiration

Tripod position and pursed lip breathing

FEV1/FVC ratio < .60 or 60%

What is the FEV1/FVC ratio indicative of emphysema?

Less than 0.60 or 60%

What is a classic physical appearance of a patient with emphysema?

Hyperinflated barrel chest and thin/emaciated body.

Pink puffer

emphysema can progress to

Cyanosis

Cor pulmonale-right-sided heart failure

LHF

primary CV complication associated with COPD and can progress to Cor Pulmonale.

pulmonary HTN

Pulmonary HTN caused by

capillaries in the lungs being damaged so the same amount of blood is pushed through fewer vessels

What is the medical management for emphysema?

Bronchodilators, supplemental oxygen, and lung volume reduction surgery, ACTs

Lung volume reduction surgery

• Surgical procedure in which a portion of lung tissue damaged by emphysema is removed

• Creates extra space in the chest so that the remaining lung tissue and the diaphragm work more efficiently, enabling the patient to breath more easily

bronchodilators

First line of therapy to increase airway size

Provides less resistance

What defines chronic bronchitis?

Excessive sputum production on most days for at least 3 months for 2 consecutive years.

What are common symptoms of chronic bronchitis?

Chronic, rattling cough and impaired mucus clearance, bronchial tubes

bronchitis associated w/

Cigarette smoking

Air pollution

Infections (Hemophilus, Strep pneumonia)

smoking predisopses those with bronchitis to

Decreased ciliary clearance

Damaged epithelium from proteases

Interference with WBC function

Irritation of airways

Hyperplasia of mucus glands in large airways

Excessive mucus production

What is the classic appearance of a patient with chronic bronchitis?

Overweight and cyanotic, often referred to as 'blue bloater.'

Hypercapnic

Cor pulmonal

Hypertrophied mucosal glands and chronic wet coughs

hypercapnic

Increase in CO but less ventilation of the alveoli

Damage to control of breathing

Lose responsiveness to CO2 partial pressure d/t too much CO2 buildup

control of ventilation in bronchitis

by PaO2

Medical Management of Chronic Bronchitis

Frequently co-morbid with emphysema

Bronchodilators

Supplemental O2

Antibiotics

Airway clearance

What is bronchiectasis?

Chronic and permanent dilation of bronchi due to inflammation or infection.

What are common symptoms of bronchiectasis?

Copious amounts of foul-smelling sputum, chronic coughing, and shortness of breath, mucus plugging

Causes of bronchectasis

CF and

non-CF which is an HIV infection, immunodeficiency, inflammatory bowel, or allergic lung inflammation

Bronchiectasis: S & S

chronic coughing

coughing up blood

abnormal sounds or wheezing in the chest on breathing

shortness of breath

chest pain

coughing up large amounts of mucus

daily bad breath odor

skin with a blue appearance

weight loss

fatigue

thickening of the skin under your nails and toes

What diagnostic tests are used for bronchiectasis?

Sputum test

Chest x-ray

Pulmonary function test

PPD test skin test may be used to check for TB

Salt test for sweat to diagnose CF

Causes of Bronchiectasis

Idiopathic

Obstruction by tumor or foreign object

Immotile cilia

Congenital

Post-infective/ Cystic fibrosisIdiopathic

Obstruction by tumor or foreign object

Immotile cilia

Congenital

Post-infective/ Cystic fibrosis

What is the role of bronchodilators in COPD management?

They are the first line of therapy to increase airway size and reduce resistance.

What is the significance of the term 'pink puffer'?

It describes the classic appearance of a patient with emphysema.

What is cor pulmonale?

Right-sided heart failure caused by respiratory disease.

What is the effect of smoking on ciliary function in the lungs?

It impairs ciliary ability to clear mucus, leading to mucus accumulation.

What is the impact of emphysema on lung elasticity?

It decreases elasticity and increases compliance, leading to difficulty in expiration.

What are the signs of respiratory failure in chronic bronchitis?

Increased CO2 levels and loss of responsiveness to CO2 partial pressure.

What is the role of airway clearance in bronchiectasis management?

It helps to remove mucus and improve breathing.

What is the relationship between COPD and lung cancer?

75% of all COPD cases occur in smokers, increasing lung cancer risk.

What is the typical appearance of a chest x-ray in emphysema?

Hyperinflated lungs with a flattened diaphragm.

What is the effect of mucus plugs in COPD?

They cause air trapping and hyperinflation during expiration.

What is bronchitis characterized by?

No change in wall diameter.

Medical/Surgical Management of Bronchietasis

• Bronchodilators

• Mucus thinners

• Oxygen therapy

• Antibiotics for infection

• ACTs

• Surgical removal if feasible

What is the primary driver of ventilation?

CO2 levels.

What happens to pH when CO2 accumulates?

pH decreases, leading to acidosis.