Western Patholgy week 10 - respiratory system

What system controls breathing?

The nervous system: brainstem regulates automatic respiration, cerebral cortex = voluntary ventilation

Where is the respiratory center in the brain?

The pons and the medulla oblongata

What are the upper airway defenses?

Normal flora, proteases and lysozymes, salivary IgA

What are the lower airway defenses?

Coughing, mucociliary clearance, IgA and IgG opsonization, antimicrobial peptides, surfactant

What are the components of the lower respiratory tract?

Trachea, bronchi, bronchioles, alveoli

What is pulse oximetry?

The 5th vital sign: assesses oxygen saturation of the blood

What is the normal pulse oximetry level?

95% or higher

What does a Pulse Ox of 94% or lower indicate?

Potential hypoxemia due to various lung/heart conditions

What are some limitations of pulse oximetry?

Poor circulation, dark skin, thick skin, smoking, dark fingernail polish, artificial nails, cool skin temperature

What are observable signs that indicate issues with respiration?

Cyanosis, pallor, asymmetry of chest expansion, labored breathing

What is the anterior-posterior to transverse ratio?

Ratio of the chest front to back vs. side to side; normal adult ratio is 1:2, child ratio is 1:1

What does an adult ratio of 1:1 indicate?

Usually a chronic respiratory condition, known as barrel chest

What is clubbing?

Symptom indicating chronic hypoxia (usually): tips of fingers enlarge, nails curve around fingertips

What does the use of accessory muscles during respiration indicate?

Labored breathing due to weakened intercostal muscles and diaphragm - sign of asthma/COPD/ resp infections/pulmonary edema. accessory muscles visible in severe cases

What is auscultation?

A medical examination technique that involves listening to sounds produced by the lungs

What is egophony?

Breath sound distortion; patient says 'A' but practitioner hears 'E' - indicates fluid/pus in lungs/chest

What are additional breath sounds called?

Adventitious breath sounds

What are common adventitious breath sounds?

Rales/crackles, rhonchi, wheezing, stridor, pleural rub

Why is coughing so important?

Major defense mechanism of the respiratory tract

What are the categories of cough duration?

Acute: less than 3 weeks, persistent: 3 to 8 weeks, chronic: over 8 weeks

What is the most common cause of an acute cough?

Viral respiratory tract infection

Differential diagnosis for acute cough?

Acute bronchitis, allergic rhinitis, sinusitis, asthma, COPD, colds, CHF, GERD, pneumonia, post infectious cough, post nasal drip, malignancy, virus

What are common causes of chronic cough?

ACE Inhibitors, post-nasal drip, GERD, other respiratory diseases

What are common lower respiratory infections?

Croup, RSV, bronchitis, pneumonia, COVID-19, tuberculosis

What is the medical name of croup?

Laryngo tracheo bronchitis

What are facts about croup?

Viral infection common in children 6 months to 5 years; causes swollen larynx, barking cough, inspiratory stridor, better with cool damp air

What is the treatment for croup?

Cool mist humidifier, cold fresh air, hydration, maybe steroids/nebulizer

What is RSV?

Respiratory Syncytial Virus; common infection that mimics a cold, dangerous in infants

What is the treatment for severe RSV?

IV fluids, oxygen therapy, hospitalization

What is acute bronchitis?

Inflammation of the tracheobronchial tree, usually viral

What are the signs and symptoms of acute bronchitis?

Cough with productive sputum, with or without fever

What is pneumonia?

An acute infection causing inflammation of the air sacs of one or both lungs, usually caused by preceding resp illness

What is the most common fatal hospital-acquired infection?

Pneumonia

What are the signs and symptoms of pneumonia?

High fever, cough with mucus, fatigue, rapid breathing/heart rate, chest pain, cyanosis

How do you diagnose pneumonia?

Chest X-ray, sputum culture, CBC with diff (leukocytosis), CT scan, blood culture

What is the treatment for pneumonia?

Antibiotics for bacterial infection, oxygen therapy, IV fluids, drain fluids if pleural effusion

What is pleural effusion?

Build up of excessive fluid between the layers of the pleura of the lungs

TX for pleural effusion?

thoracentesisn - surgical drainage/duiretics/antibiotics

results of untreated pneumonia

acute respirator distress syndrome (ARDS), lung adscess, sepsis

What are the two stages of tuberculosis pathogenesis?

Primary and secondary infections.

What is the death rate from tuberculosis?

2000/year.

What is the highest mortality rate associated with tuberculosis?

folks with HIV

What bacteria causes tuberculosis?

Mycobacterium tuberculosis.

How long can Mycobacterium tuberculosis survive in dried sputum?

For weeks.

What can destroy Mycobacterium tuberculosis?

UV light, heat, alcohol, and formaldehyde.

What is a Ghon complex?

Pulmonary lesions of fibrous tissue/calcifications that form around TB tubercles.

pathophysiology of PRIMARY TB infection?

-bacterial containing droplet (mycobacterium tuberculosis) is inhaled into lungs

-initial immune response result = macrophages engulf the bacteria and form granulomas

-granulaoma becomes tubercle which is walled off by fibrous tissues

-remains latent until immune system is impaired enough to cause Active TB

What are the signs and symptoms of primary tuberculosis?

Asymptomatic.

What are the signs and symptoms of secondary tuberculosis?

Anorexia, malaise, fatigue, night sweats, afternoon fever, persistent worsening cough with purulent/bloody sputum.

What tests are used to diagnose tuberculosis?

Tuberculin skin test, chest X-ray, CT scan, sputum culture.

What antibiotics are used to treat tuberculosis?

Rifampin, Isoniazid, Rifapentine.

facts about COVID-19?

caused by SARS-CoV-2>cytokine storm>severe inflammation>pneumonia/lung tissue damage

What is asthma?

A chronic inflammatory disease of the airways.

What diseases are associated with allergic asthma?

Eczema, food allergies, allergic rhinitis.

What happens to bronchioles in an asthmatic lung?

Muscles tighten, lining swells, and excess mucus obstructs the passageway.

What is air trapping in asthma?

Mucus causes partial obstruction, trapping air in distal areas, causing hyperinflation of lungs

What is atelectasis?

Collapsed lung, often resulting from mucus obstruction in alveoli - different than pneumothprax where air accumulates in pleural space

What are some asthma triggers?

Environmental allergens, weather changes, infections, exercise, inhaled irritants, stress, GERD, aspirin/NSAIDs.

What are the signs and symptoms of asthma?

Wheezing, dyspnea, chest tightness, cough, racing heartbeat, nighttime episodes, rapid breathing.

What is status asthmaticus?

A medical emergency with a persistent asthma attack that does not respond to therapy.

How is asthma diagnosed?

Spirometry and peak flow measurements.

What is spirometry?

common test for lung capacity

What is peak expiratory flow (PEF)?

A handheld device for home monitoring of asthma severity.

What symptoms classify asthma as controlled or not?

Daytime symptoms >2x/week, nighttime awakenings, impact on daily activities, rescue meds > 2x/week

What are the most common medications for asthma?

Short-acting bronchodilators, corticosteroids, leukotriene receptor agonists.

What is a rescue inhaler?

Short-acting beta agonist bronchodilators (SABAs) like Albuterol.

What is used as maintenance medication for asthma?

Long-acting beta agonists (LABAs)or glucocorticoids: Advair (salmuterol), Symbicort (budesonide), Flovent (Fluticasone)

What are leukotriene modifiers?

Long-term asthma control medications that block leukotrienes, stopping inflammation: Singulair (Montelukast)

What are common side effects of leukotriene modifiers?

Anxiety, depression, confusion, mood lability, sleep disturbance, suicidal thoughts.

What is a nebulizer?

A device that turns liquid medicine into mist for respiratory treatment.