Physiology Exam 4- IU P225

Ideal gas and Boyles law

increase in volume -> decrease in pressure & decrease in volume -> increase in pressure

ventilation

breathing

inspiration

inhalation

expiration

exhalation

quiet breathing inspiration is

active

quiet breathing expiration is

passive

partial pressure

pressure contributed by individual gas

Po2

Patm x % of gas in atm

Dalton's law

total pressure of a mixture of gasses is the sum of the partial pressures of the individual gasses

Boyle's law

P1 x V 1 = P2 x V2

Ideal gas equation

PV=nRT

pulmonary circulation

volume ≈ 0.5L

pulmonary flow

systemic flow ≈ 5L/min

pulmonary arterial pressure

≈ 25/8 mmHg

connective tissue between alveoli

elastin & collagen

alveoli

respitory 'membrane', type 1 cell, capillary endothelium

smokers cough function

replaces function of mucociliary escalator, damages cells with immune functions

smokers cough problem

paralysis or destruction of ciliated columnar epithelial cells

cystic fibrosis

mutation of CFTR channels, poor CTFR function

what causes cystic fibrosis

reduced saline layer- build up of thick mucus restricts mucociliary escalator- bacterial infections

mucociliary escalator

Na+/K+ ATPase pump, NKCC symporter: Na+, K+, 2Cl-, CTFR channel, paracellular movement

filtering air pathogens and irritants

ciliated epithelium, submucosal glands, goblet cells, basal cells

Warming air

external air temp vs. body temp, nasal vs. oral pathways

moistening air

atmospheric humidity vs body humidity, nasal vs oral pathways

functional divisions

conduction zone, respiratory zone

conduction zone

transport & conditioning of air, trachea & bronchi

respiritory zone

gas exchange, respitory bronchioles, alveolar ducts, alveoli

lower respitory system

air only, respiritory tree, alveoli

upper respiratory system

food & air, oral or nasal cavity, pharynx, larynx

functions of the respiritory system

external gas exchange, regulation of blood pH, protection from pathogens, detection of odors, vocalization

Components of the respiritory system

airway, lungs, supporting systems

alveolar gas exchange

air

systemic gas exchange

internal respiration, blood

external respiration

pulmonary ventilation

cellular respiration

aerobic cellular respiration

delta p

air pressure measured in mmHg

delta p between alveoli (alv) and atmosphere (atm)

delta P = Palv -Patm

Palv = Patm

air flows from a higher pressure to a lower pressure

Palv < Patm

Into the lungs (inspiration or inhalation)

Palv > Patm

out of the lungs (expiration or exhalation)

increase in airway radius

decreases resistance

increase in airway length

increases resistance

4 lung volumes?

tidal volume, inspiratory reserve volume, expiratory reserve volume, residual volume

4 lung capacities?

functional residual capacity, inspiratory capacity, vital capacity, total lung capacity

lungs and thorax contain?

chest wall, vertebrae, ribs, sternum, muscles, connective tissue

diaphragm contains?

pleural sac, visceral pleura, parietal pleura, pleural cavity with intrapleural fluid

inspiration means

quiet breathing, diaphragm contracts, 60-75% volume change, rib cage expands 25-40% of volume change

expiration means

quiet breathing, diaphragm relaxes 60-75% of volume change, rib cage relaxes 25-40% of volume change

mechanical factors in ventilation

compliance deltaV/deltaP, elastic recoil

ventilation base pressures?

atmospheric pressure (Patm), intrapleural pressure (Pip), Alveolar pressure (Palv)

ventilation transmural pressures at rest?

transpulmonary pressure (Ptp) holds lungs open, Chest wall pressure (Pcw)- holds chest wall in, respiratory system pressure (Prs)- a gradient between alveoli and atmosphere

starting inspiration

no air flow

during inspiration

negative pressure gradient

ending inspiration

no air flow

Palv

inhale

Palv>Patm

exhale

how does inspiration happen?

contract inspiratory muscles

how does expiration happen?

relax inspiratory muscles

quiet vs deep breathing

quiet: diaphragm, external intercostals. deep or active: sternocleidomastoid and more effort from external intercostals

pneumothorax

air in pleural cavity

what is lung recoil for

expiration

what is lung compliance for

inspiration

airway diameter?

inspiration vs. expiration

bronchoconstriction?

decreases diameter, increases resistance

bronchodilation?

increases diameter, decreases resistance

hypoventilation?

decrease alveolar ventilation below metabolic demand

alveolar Pco2 > 40 mmHg

CO2 production vs CO2 excretion

alveolar Po2 < 100 mmHg

O2 consumption vs O2 intake

hyperventilation

increased alveolar ventilation above metabolic demand

alveolar Pco2 < 40 mmHg

CO2 production vs CO2 excretion

Alveolar Po2 > 100 mmHg

O2 consumption vs O2 intake

eupnea

normal quiet breathing

hypernea

increased respiratory rate and/or volume in response to increased metabolism

tachypnea

rapid breathing, usually increased respiratory rate with decreased depth

dyspnea

difficulty breathing (a subjective feeling)

apnea

cessation of breathing

ventilation perfusion matching

zone 1 (apex): V/Q > 1, Zone 2 (middle): V/Q = 1, Zone 3 (base): V

Normal V/Q, healthy individual

avg V/Q = 0.8

exercise breathing

increased blood flow to apex

V/Q mismatches

shunt: poor alveolar ventilation (V), alveolar dead space

obstructive lung diseases (expiration is difficult)

COPD (chronic, emphysema), asthma (bronchoconstriction)

restrictive pulmonary diseases (inspiration is difficult)

idiopathic pulmonary fibrosis (unknown cause), pulmonary sarcoidosis, pneumonia

Surgery with anesthesia

reduced surfactant production

newborn respiratory distress syndrome

surfactant production not adequate until around 34 weeks

DIAGRAM: alveolar gas exchange

O2: alveoli -> blood:1, CO2: blood -> alveoli:6

DIAGRAM: gas transport

2&5

DIAGRAM: systemic gas exchange

O2: blood -> cell:3, CO2: cell -> blood:4

monitor systemic arterial Po2

95 mmHg (range: 85-100)

monitor systemic arterial Pco2

40 mm Hg (range 35-45)

monitor systemic arterial pH

normal pH: 7.38-7.42

transportation of gasses Po2

100 mmHg (85-100)

transportation of gasses Pco2

40 mmHg (35-45)

transportation of gasses Hb

98-100% saturated

transportation of gasses pH

7.4(7.38-7.42)

systemic veins pulmonary arteries Po2

Po2

systemic veins pulmonary arteries Pco2

Pco2 > or equal to > 46 mmHg

systemic veins pulmonary arteries Hb

75% saturated

systemic veins pulmonary arteries pH

7.37

what three factors affect alveolar gas exchange

alveolar Po2 and availability of O2, gas diffusion between alveoli and blood, and perfusion of alveoli

partial pressure gradient between alveoli and blood

alveolar Po2=100 mmHg vs pulmonary capillary blood Po2 < or equal to < 40 mmHg