Respiratory system

air conduction portion

delivers air to the lungs

gas exchanging portion

allows oxygen to enter blood and carbon dioxide to be removed

What are gas exchanging structures?

lungs, alveoli, & capillaries

bronchiole Function

smooth muscle allows dilation (increase airflow) and constriction (decreased airflow)

What happens with excessive bronchiole constriction?

dangerous reduction in airflow and difficulty breathing

What can excessive bronchiole constriction cause?

respiratory distress or failure

What are air containing particles?

bacteria, viruses, fungi, dust, pollen & pollutants

mucus function?

traps particles like bacteria, dust and pollutants

cilia function?

moves mucus upward to be expelled

What happens if cilia is damaged?

mucus build up in lungs, increased risks of respiratory infections, reduced lung function

effect of smoking

reduces mucus and destroys cilia

effect of alcohol on cilia

paralyzes cilia

primary site of gas exchange

alveoli

alveolar surfactant

lipoprotein that reduces surface tension and prevents alveolar collapse

what does alveolar surfactant improve?

pulmonary compliance

atelactasis

collapse of alveoli due to lack of surfactant or other casues

who is at risks for low surfactant?

premature infants and smokers

hering-breuer reflex

prevents lung overinflation by stopping inspiration when lungs are stretched

primary regulator of breathing

carbon dioxide

how do lungs regulate pH?

by adjusting breathing rate to control carbon dioxide levels

What happens when breathing increases(hyperventilation)?

carbon dioxide dcreases —> blood is less acidic

what happens when breathing decreases(hypoventilation)?

carbon dioxide increases —> blood is more acidic

Tidal volume(TV)

normal breathing (500 ml)

Inspiratory Reserve Volume(IRV)

extra air inhaled beyond normal breath

Expiratory Reserve Volume (ERV)

extra air exhaled beyond normal exhalation

vital capacity (vc)

tv + irv + erv

residual volume (rv)

air left after forceful exhalation

when does surfactant fully develop?

around 36 weeks gestation

new born characteristics?

nasal breather

when do lungs fully mature?

around 25 years

aging effects on lungs

decreases elasticity, weaker diaphragm, decreased gas exchange

effect of aging on immune system

increased infections

impaired gas exchange(nursing diagnosis)

reduced oxygen/carbon dioxide exchange —> asthma

ineffective airway clearance

blocked airflow due to secretions—> pneumonia

Upper Respiratory Tract Structures

nose, mouth, sinus, pharynx, larynx

Lower Respiratory Tract Structures

trachea, bronchi, bronchioles, alveoli

Cause of infection rhinitis(common cold)

usually viruses (rhinovirus)

incubation period for common cold

1-3 days(usually) ~ 7

Incubation period

time between exposure and symptoms

pnemonia

inflammation of lungs affecting alveoli, alveolar ducts and bronchioles

how does common cold spread?

hand to hand, hand to mucous membrane, contaminated surfaces

infectious agents(pneumonia)

bacteria, virus, fungi

non-infectious agents(pneumonia)

aspiration, smoke, toxins

most common bacterial cause(pneumonia)

streptococcus pneumonia

aspiration pneumonia

inhalation of gastic content intto lungs

risk for aspiration pneumonia

impaired gag reflex

Asthma

chronic pulmonary disease with intermittent, reversible airway obstruction

intermittent

occasional pain

effects on ventilation

airway inflammation—> swelling narrow airways

increased mucus production—> blocked airways

bronchospasm—> muscle tightening around airways

asthma symptoms

dyspnea, wheezing, cough, chest tightness, fatigue

status asthmaticus

life threatening, prolonged asthma attack unresponsive to usual treatment

risk factors for atelectasis

surgery and immobility

pathophysiology of atelectasis

collapsed alveoli—>poor ventilation—>impaired blood flow—> reduced gas exchange

clinical manifestation of atelectasis

dyspnea, tachypnea, cyanosis(severe), decreased breath sounds, hypoxemia

prevention of atelctasis

frequent mobility, coughing, deep breathing, incentive spirometry