4-Pulmonary System Overview

Question 1

important elements of respir sys

full list

Answer 1

1. mechanism for centrally regulating ventilation
2. air pump
3. surface for gas exchange
4. mechanism for gas transport
5. circulatory system
6. mechanism for reg distribution of blood

Question 2

important functions

condensed

Answer 2

1. gas exchange/metabolism
2. acid base balance
3. phonation
4. defense mech/handle bioactive materials

Question 3

upper airway structures

Answer 3

1. nasal cavity
2. paranasal sinuses
3. pharynx
4. larynx

Question 4

upper airways function

Answer 4

1. air conditioning for respir sys
2. source of resistance to airflow
3. warm inspired air to body temp
4. humidify/saturate with water inspired air for gas exchange
5. filter/entrap/clear particulates
6. defense by nasal epithelium secretions

inc secretions = inc resistance

Question 5

airway generations

Answer 5

0 = trachea
1-10 = bronchi (with cartilage)
11-16 = bronchioles (no cart)
17-19 = respiratory bronchioles
20-22 = alveolar ducts
23 = alveolar sacs

16 terminal bronchioles

Question 6

bronchus characteristics

Answer 6

1. mucus blanket
2. goblet cells
3. smooth muscle
4. mucus glands
5. cartilage

G1-10

Question 7

bronchioles characteristics

Answer 7

1. ciliated epithelium
2. thin smooth muscle
3. elastic tissue
4. NO cartilage
5. goblet cells (up to terminal bronchioles then no)

G11-19

Question 8

alveolus characteristics

Answer 8

1. NO smooth muslce
2. NO cart
3. just elastic tissue

Question 9

non adrenergic non cholinergic nerves

NANC

Answer 9

when activate = relaxation of bronchiolar smooth muscle via NO and vasoactive intestinal peptide

Question 10

adrenergic activation

Answer 10

abundant B2 adrenoreceptors to relax/bronchodilate

Question 11

muscarinic acetylcholine receptors

Answer 11

parasymps stim to contract bronchiolar smooth muscle and inc glandular secretions

Question 12

irritant receptors

Answer 12

activation in trachea and bronchi = reflex contraction of smooth muscle + stim mucosal glands in resp to irritant

Question 13

mucus production system

Answer 13

1. gel layer
2. sol layer
3. goblet cells (prod mucus esp inc when smoke or pollutants)
4. submucosal glands (mucus and serous cells, present where cartilage at, controlled by ANS)

Question 14

periciliary fluid

Answer 14

makes up sol layer of mucus blanket
-made by ciliated epi cells
-maintained by chloride secretion and sodium absorption

transports mucus with pollutants out of respir system after gets trapped in gel layer

Question 15

cystic fibrosis

Answer 15

mutation in CFTR
-abnormal Cl secretion = disinhibit Na channel so sol layer becomes dehydrated (water move out of periciliary mucus)

freq lung infection and damage, xs thick mucus, salty skin/sweat, poor growth

survival age 40

Question 16

treating cystic fibrosis

Answer 16

goal to prevent/control infections + remove mucus from lungs

-use meds to target mutations or infection or bronchodilators
-PT to improve mucus clearance and fix posture, percussion

Question 17

respiratory unit consists of

Answer 17

1. bronchiole
2. alveolar ducts
3. atria
4. alveoli

site of gas exchange

Question 18

pores of kohn

Answer 18

pores b/t adjacent alveoli so collateral ventilation occurs if lung partially deflated
-bad though for passage of fluid and bacteria

Question 19

cell types on alveolar surface

Answer 19

1. type I = make up the wall/surface area, flat cells with large cytoplasmic extensions, fewer than II
2. type II = larger/thicker cells, produce surfactant
3. macrophages = engulf and destroy foreign material

Question 20

respiratory membrane

Answer 20

fused basement membranes of capillary and alveolaus but leaky
-site of gas exchange

Question 21

respiratory membrane made of

Answer 21

1. layer of fluid lining the alveolus with surfactant
2. alveolar epithelium
3. epithelial basement membrane
4. interstitial space
5. capillary basement membrane
6. capillary endothelial membrane

Question 22

lung interstitium composition

Answer 22

1. lymphatics
2. capillaries
3. immune cells
4. fibroblasts
5. connective tissue (collagen/elastin)

Question 23

interstitial lung disease

Answer 23

interstitium enlarged with inflamm cells and edema fluid or increased extracellular matrix
-will interfere with gas exchange

Question 24

pleural membranes

Answer 24

single continous membrane that folds back on itself
-lines lungs with visceral pleura and chest cavity with parietal

Question 25

pleural space

Answer 25

normally intrapleural space is virtual and pressure should be more neg than intrapulmonary (alveolar space) has small amount of pleural fluid

Question 26

pleural fluid function

Answer 26

important for transmitting the force produced by chest expansion to the long parenchyma creates suction/vacuum b/t two surfaces = sub atmospheric pressure

Question 27

pleural fluid flow

Answer 27

1. made by microvessels of the parietal pleura 2. removed from pleural space by stomata 3. lymphatic channels

Question 28

pleural effusion

Answer 28

excess of pleural fluid that disrupts mechanical coupling b/t chest wall and lung -lung pulls away from chest wall -atelectasis (partial collapse of lung), compression

Question 29

precipitating conditions pleural effusoin

Answer 29

1. inc microvascular hydrostatic pressure 2. dec colloid oncotic pressure 3. inc microvascular permeability 4. impaired lymph drainage 5. diaphragmatic defects

Question 30

symptoms of pleural effusion

Answer 30

often no symptoms unless effusion is moderate/large or inflammed -SOB -chest pain with deep inhalation, pleuritic pain -fever -cough treat underlying cause or thoracentesis

Question 31

pneumothorax

Answer 31

air in pleural cavity = partial or complete lung collapse -spontaneous or trauma (penetrating, blunt) usually asymptomatic unless larger then dyspnea and pleuritic chest pain treat with catheter aspiration or tube thoracostomy after get x ray

Question 32

tension pneumothorax

Answer 32

progressive inc in pleural pressure due to one way flow or air -air goes in but not out -very serious > severe hypotension/shock from dec venous return (vena cava is compressed)

Question 33

tidal volume

Answer 33

volume of air associated with normal resting breathing (1/2 L)

Question 34

inspiratory reserve volume

Answer 34

amount of volume between normal resting inspiration and maximal combines with tidal volume for inspiratory capacity

Question 35

residual volume

Answer 35

vol in lungs after maximal expiration combines with expiratory reserve = functional residual capacity

Question 36

vital capacity

Answer 36

total volume between maximal inhalation and exhalation