Respiratory Flashcards
What are the three main functions of the respiratory system?
- deliver O2 to cells
- eliminate CO2 from body
- regulate blood pH
What is respiration?
-exchanges that lead to uptake of O2 by cells and release of CO2 to lungs
What are the four steps for respiration?
- ventilation
- exchange between alveoli and pulmonary capillaries = external respiration
- transport of gases in blood
- exchange between blood and cells = internal respiration
what is cellular respiration?
-use of O2 in ATP synthesis
What are the four parts of the bronchial tree?
-trachea
-bronchi
-bronchioles
-alveoli
What is the relationship between alveolar pressure and intrapleural pressure and the volume of air moved?
-during inspiration: both alveolar and intrapleural pressure decrease
-during expiration both increase
ventilation graphs?? slide 6
What is inspiration?
-occurs as alveolar pressure drops below atmospheric pressure
What is the timeline of inspiration?
-time 0: atmospheric pressure = alveolar pressure
-time 0-2sec: alveolar pressure drop to -1mm Hg
who is the cutest poopie that there is ??
akichan
What do +ve and -ve mmHg values correspond to?
+ve = above atmospheric pressure
-ve = below atmospheric pressure
What are the 5 factors that affect ventilation?
-length of system
-viscosity of air
-diameter of airway
-upper airways
-bronchioles
Which of the ventilation factors can be changed?
-diameter of airway
What are upper airways affected by?
-physical obstruction
What are bronchioles affected by?
-bronchoconstriction
-bronchodilation
What is bronchoconstriction mediated by?
-parasympathetic neurons
-muscarinic receptors, histamine, leukotrienes
What is bronchodilation affected by?
-CO2
-epinephrine
What are the three neuroendocrine systems that mediate physiological bronchial tone?
- parasympathetic system
- sympathetic system
- non-adrenergic, non-cholinergic (NANC)
Which neuroendocrine system involved is dominant?
-parasympathetic
What does the parasympathetic system do to the respiratory tract?
-dominant efferent pathway providing baseline tone
-mild-bronchoconstriction
What does the sympathetic system do to the respiratory tract?
-beta 2-adrenergic-mediated broncho-dilation = reduce parasymp bronchoconstriction
-alpha 1-mediated bronchoconstriction (minimal)
What does the NANC system do to the respiratory tract?
-bronchodilation via neurotransmitters
-ex. vasoactive intestinal peptide
What does chronic severe asthma look like compared to no asthma?
-alveoli and ducts swell and become thicker = harder to exchange gases
-decreased surface area = less exchange
-in very chronic = the exchange surface is destroyed
What is a cough?
-forced air expiration against a closed glottis which expels air and unwanted material
-voluntary or involuntary
What is the pathway for a cough?
mucosal surface lining respiratory tract -> impulses relayed via vagus nerve -> cough center in brain -> efferent stimulus -> diaphragm, glottis, chest and abdomen muscles
What is asthma?
-chronic inflamm disorder
-inflammation causes wheezing, breathlessness, chest tightness, coughing
-associated with widespread airflow obstruction
-reversible
-associated with bronchial hyperresponsiveness
How does cold environment make asthma worse?
-the air is drier
-cold = body pulls blood to center and everything constricts = decreased blood flow
What are the other names for exercise-induced bronchoconstriction?
-exercise-induced asthma
-exercise-induced bronchospasm
-postexercise bronchoconstriction
-thermally induced asthma
What is the possible pathway for asthma?
-environmental and genetic causes -> inflammation -> airway response -> breathing limitation
-triggers (allergy, infectious, irritant, exercise) -> symptoms -> breathing limitation & airway response
What is emphysema?
-destroyed gas exchange surfaces in alveoli
-describes one of many abnormalities in COPD pt
What is chronic bronchitis?
-cough and sputum for min 3 months each year for two years in a row
-related to COPD but doesn’t reflect the major impact
What is COPD?
-chronic obstructive pulmonary disease
-umbrells term for things with limited airflow
-progressive, small airway disease and parenchymal destruction
-abnormal infl response
-preventable and treatable
What are the two possible mechanisms of COPD?
-inflammation -> small airway disease = infl and remodelling -> airflow limitation
-inflammation -> parenchymal destruction = lose alveoli; dec. elastic recall -> airflow limitation
What factors can increase the risk of COPD?
-genes
-exposure to smoke, dust, pollution
-oxidative stress
-socioeconomic status
-nutrition
-asthma
What is the difference between asthma and COPD?
-asthma cause: eosinophilic inflammation
-COPD cause: neutrophilic inflammation
How is asthma and COPD related?
-they can coexist
-can be distinguished from one another usually
-sometimes cant differentiate in a pt
What are the clinical suggestive features of COPD?
-onset midlife
-slowly progresses
-long smoking history
-dyspnea during exercise
-irreversible airflow limitation
What are the clinical suggestive features of Asthma?
-onset early in life
-symptoms change day to day
-worse early morning, night
-family history of asthma
-also has allergy, rhinitis, eczema
reversible airflow limitation
