L7 Control of Ventilation During Ex

conducting zone

nose to terminal bronchioles

respiratory zone

respiratory bronchioles and alveoli

inspiratory muscles

diaphragm and external intercostals

accessory inspiratory muscles

sternocleidomastoid, scalene, pectoralis minor, ex and int intercostal, serratus anterior

passive expiratory mucsles

none, passive effort

active expiratory muscles

internal intercostals , rectus abdominus, external oblique

circulatory transport

transport of respiratory gases in the blood between the lungs to the cells of the body

Symmorphosis

quantitative match of design and function with a defined functional system

Pulmonary ventilation

movement of air into and out of the lungs

Pulmonary ventilation formula

V = Vt x f

alveolar ventilation

the amount of air that reaches the alveoli

alveolar ventilation formula

Va = Vt - Vd

% O2 and % Co2 in atm

20.93%, 0.03%

Resistance equation

change in pressure/flow

Fick's Law of Diffusion

The rate of gas transfer (V gas) is proportional to the tissue area, the diffusion coefficient of the gas, and the difference in the partial pressure of the gas on the two sides of the tissue, and inversely proportional to the thickness.

Henry's law

the dissolution of gases in blood is impacted by temp, partial pressure, and solubility

Dalton's Law of Partial Pressures

states that the total pressure of a mixture of gases is equal to the sum of the pressures of all the gases in the mixture

ventilation-perfusion ratio

the ratio between ventilation and perfusion in the lung; matching of ventilation to perfusion optimizes gas exchange

what happens to V/Q ratio during exercise

-mild/moderate = increases from approx 0.8 to 1 (ideal),

-severe = increase to 2-3 (not good mismatch)

FEV1

forced expiratory volume in 1 second

FEV1/VC ratio

≥80% is normal for healthy individuals

Work of Breathing (WOB)

The effort required to expand and contract the lungs

WOB equation

change in pressure x change in volume

What happens to whole body VO2 when WOB is lower

whole body VO2 decreases

what are the driving factors of gas diffusion

partial pressures of O2 and CO2

airflow equation

= (P1-P2)/resistance

minute ventilation

tidal volume x respiratory rate (f)

total minute ventilation formula

V= Va +Vd

vital capacity

The total volume of air that can be exhaled after maximal inhalation.

residual volume

Amount of air remaining in the lungs after a forced exhalation

total lung capacity

vital capacity + residual volume

Henry's Law

amount of O2 and CO2 dissolved in blood depends on temp, partial pressure, and solubility of the gas

myoglobin

Functions as an O2 "shuttle" from the muscle cell membrane to mitochondria

does myoglobin or Hb have a higher affinity for O2

myoglobin

O2 reserve

O2 stored with myoglobin to be used during exercise

effect of exercise on V/Q ratio

improves, enhancing gas exchange

what factors impact work of breathing during exercise

viscoelastic and resistive properties

perfusion and ventilation matching is dependent on

connective and diffusive factors in the lungs and pulmonary artery