Chapter 34: structure and function of the pulmonary system

3 processes of the pulmonary system

ventilation, diffusion and perfusion

movement of air into and out of the lungs

ventilation

movement of gases between air spaces in the lungs and the blood stream

difffusion

movement of the blood into and out of the capillary beds of the lungs to body organs and tissues

perfusion

what system carries out ventilation and diffusion

pulmonary system

what system carries out perfusion

cardiovascular system

function of upper airways

warms and humidifies air; removes foreign particles

upper airways

lines with ciliated mucosa, warms, filters adn humidifies air

components of the upper airways

nasopharynx, oropharynx

connects upper and lower airways

larynx

components of the lower airways

trachea, bronchia, terminal bronchioles

how much more likely is CO to bond to hemoglobin vs O2

200x

what can cause falsely high hemoglobin saturation rates

carbon monoxide poisoning

gas exchanges airways

respiratory bronchioles, alveolar ducts, alveoli

primary gas exchange units

alveoli

ridge where the trachea divides into the right and left bronchi

carina

cells that produce mucus in the lungs

goblet cells

function of goblet and cilia cells

propel foreign material upward to enable it to be coughed up

t/f there is a normal microbiota in the lungs

true

which filter is better the nasopharynx or the oropharynx

nasopharynx

provide passage for movement of air into and out of the gas-exchange portion of the lung

conducting airways

when is the nasophrynx used

quiet breathing

when is the oropharynx used during breathing

increased demand or nose is obstructed

function of the larynx

connect upper and lower airway, contain vocal folds and cords. laryngeal box with epiglotttis thyroid and cricoid cartilage

u shaped cartilage that connects the larynx to the bronchi

trachea

divided at carina dn is very sensitive "soughing and airway narrowing"

bronchi

root of the lungs

hila

consist of epithelial layer and a thin elastic basement membrane but no muscle layer

alveolar septa

provide alveolar structure

type 1 alveolar cells

produce surfactant in the alveoli

type ii alveolar cells

lipoprotein that coats the inner surface of teh alveolus and facilitates its expansion during inspiration

surfactant

phagocytes that ingest foreing material and remove it through the lymphs

alveolar macrophages

how do the lungs buffer acid-base in body

exhalation of co2 and water

which system is quicker for buffering

the lungs/respratory

breathing present when a pt is breathign deeply due to acidosis

kussmal breathing

what test can be done to determine if an issue is compensatory/primary respiratory or acidosis/alkalosis

abg

which type of alveolar cell allows for better gas exchange by producing surfactant

type ii

the distance between the capillaries and alveolus for diffusion

alveolocapillary membrane

Pores of Kohn

small openings in the alveolar walls that allow gases and macrophages to travel between the alveoli

which lower airways have mucus layers

trachea and bronchus, bronchiole, respiratory bronchiole

which lower airways ahve serous layers

trachea and bronchus

which lower airways have goblet cells

trachea and bronchus

which lower airways have ciliated cells

trachea and bronchus, bronchiole, respiratoyr bronchiole, alveoli

which lower airways have basal cell layers

trachea and bronchus, bronchiole, alveoli, respiratory bronchiole

which lower airways have a lamina propria layer

trachea and bronchus, bronchiole, respiratory bronchiole

which lower airway hase a clara layer

bronchiole, respiratory bronchiole

which lower airway has nerve layers

respiratory bronchioles

which lower airway has capilary lumen, type ii alveolar cell, surfactant, alveolar macrophages and type 1 alveolar cells

alveoli

pulmonary circulation functions

facilitate gas exchange, deliver nutrients to lungs tissues, act as blood reservoir for lv, serves as filtering system

which pressure is lower pulmonary circulation or systemic

pulmonary (18 vs 90)

what amount of pulmonary vessels are usually filled at any given time

1/3

the bronchial circulation is part of the

systemic circulation

where does the bronchial circulation supply nutrients to

conducting airways, nerves, lymph nodes, large pulmonary vessels, pleura

the bronchial circulation supplies nutrients to

conducting airways, nerves, lymph nodes, large pulmonary vessels, and membranes

where does the deep lymphatic capillaries begin

level of terminal bronchioles

are there lymphatic structures in the acinus

no

how does fluid from the alveolar macrophages get to the lymphatic system

migrate from alveoli to terminal bronchioles

what vessels drain the pleura

superficial lymphatic capillaries

which lymphatic vessels leave the lung at the hilus

deep and superficial

how is the bronchial circulation unique

not every capillary drains into its own venous system some drains into the pulmonary vein meaning there is a mixture of oxygenated and deoxygenated blood

t/f the bronchial system does participate in gas exchange

f

what type of capillaries surround the acinus

pulmonary capillaries

what structures are included in the alveolocapillary membrane

alveolar epithelium alveolar basement membranes, interstitial space, capillary basement membrane, capillary endothelium

t/f gas exchange occurs at the alveolocapillary membrane

true

two main types of pulmonary disease

obstructive or restrictive

pressure in the pleural space

negative -4 to -10mmHg

ABG is the the only. true way to evaluate what

alveolar ventilation

what does the term respiratory mean

exchange of o2 and co2 during cell metabolism

ventilatory rate (breaths per minute) multiplied by the volum of air per breath liters per breath or tidal volume

minute volume

What are the three respiratoyr centers

dorsal respiratory group, ventral respiratory group, pontine respiratory group

where is each of the respiratory centers located

DRG and VRG in the medulla, PRD in the pons

function of the DRG

control of respiration and initiation inspiration

fucntion of vrg

both inspiration/expiraiton, active in forceful breathign and inactive during quiet respiration

function of prg

connections between pneumotaxic and apneustic centers

structure in the brainstem that transmits impulses to the respiratory muscles causing contraction and relaxation

respiratory centers

what is a respiratory center composed of

several group of neuron located bilaterally in the brainstem

when is voluntary breathing necessary

talking, singing, laughing and holding one's breath

located in the pons and affect depth and rate of breathing

pneumotaxic center and apneustic center

central chemoreceptors

refects PaCO2, stimulated by hydrogen in cerebrospinal fluid, increases the respiratory depth and rate

peripheral receptors

located in aortic and carotid bodies stimulated by hypoxemia, responsible for all of the increase in ventilation that occurs in response to arterial hypoxemia

found in epithelium of conductino airways, cough relex bronchoconstriction and increased ventilatroy rate, locaed in proximal and larger airways and nearly absent in the distal airway thus is is possible for secretion to accumulate without initiating cough

irritant receptors

based on hering-bruere expiratory reflex, very active in newborns or in adults with high tidal volumes (exercise), locatedin smooth muscles of airways and are sensitive to increases in the sizze or volume of the lungs.

stretch receptors

juxtapulmonary capillary receptors sens alveolar size, located near capillaries in alveolar septa, sensitive to increase pulm cap pressure whihc stimulates shallow rapid breathing, hypotension and bradycardia

j receptors

the lung is innervated y

fibers of sypathetic division and parasympathetic division of ans

how do supathetic fibers get to the lungs

from upper thoracic and cervical ganglia

how do fibers of the parasympathetic travel in the lungs

vagus nerves

parasympathetic fibers cause \___ and sympathetic receptors cause \____

contraction, relaxation

bronchial smooth muscle needs equal stimulation of

contraction and relaxation

what is the main controller of the lungs under normal conditions (PNS, SNS)

parasympathetic

major muscles of inspiration

diaphragm and external intercostal muscles

accessory muscles of inspiration

sternocleidomastoid and scalene muscles

accessory muscles of expiraiton

no major for passive, abdominal and internal intercostal

slide 39-40

Within the alveolus \___ make expansion difficult

surface tension

how does surfactant lower surface tension in the alveoli

by coating the air-liquid interface in the alveoli, detergent like affect that separates liquid molecules

measure of lung and chest wall distensibility, the reciprocal of elasticity

compliance

increased compliance indicates

easy for lungs to inflate and loss of some recoil

decreased compliance can be seen in

ARDS, pulmonary edema, fibrosis, pneumonia

airway resistance is determined by

length, radius, diameter, velocity, and viscosity

the smaller the sphere

the harder to dilate