3.1 Pulmonary Pathology

What are the 4 physical properties of the lungs

compliance

elasticity

surface tension

resistance to airflow

define compliance

the ability of the lings to expand/distend

Why is it essential that the residual volume remain in relation to compliance

having a little bit of air within the lungs before trying to inflate will cause the lungs to be more compliant

Compliance ____ as you reach TLC

decreases

define elasticity

the ability of an object/material to resume its normal shape after being stretched or compressed (ability to recoil)

What causes elasticity

change in pressures and the elasticity of the lung tissue

What is the risk with lungs becoming over compliant

decrease elasticity

what causes surface tension

the air/water interaction

Why can moisture in alveolar sacs be dangerous id not properly gerring air in

the sides can come together and cause the sac to collapse

What is the role of surfactant

keeps the sacs with unequal pressures open by equalizing the pressures/changing the refill times

What causes an increased resistance to flow

bronchoconstriction

PSNS

mucous and edema in airway

What causes a decrease in resistance to flow

SNS

bronchodilation

What is resistance to flow mainly based off of

vasomotor tone

Absolute lung volume factors

height/weight

age

gender

ethnicity

What are the affects of height on absolute lung volume

taller: larger

shorter: smaller

What are the affects of weight on absolute lung volume

increased central waist: smaller

decreased central waist: larger

What are the affects of age on absolute lung volume

lung function peaks at 25 y/o and decreases over time

What are the affects of genderon absolute lung volume

males have typically larger lungs

What are the affects of ethnicity on absolute lung volume

European decent: larger

African decent: smaller

Clinical signs of pulmonary pathology

abnormal PFT

Chest XR

ABGs

Auscultation

CV (bradycardia or hemorrhage)

vital signs

cor pulmonale

What are signs

objective tests done to show pathology

What are symptoms

what the pt is experiencing to indicate pathology

Clinical symptoms of pulmonary pathology

respiratory pattern

nasal flaring

grunting

crying with decreased volume/strength (silent)

cyanosis

dyspnea

cough

weight loss

define ventilation

movement of air (gas) in and out of lungs

normal resting RR

12-20 breaths/min

normal resting TV

~350-500 mL/breath

how is ventilation calculated

=volume/min

normal ventilation rate

~5 L/min

define tidal volume (TV)

volume of air inhaled and exhaled with each breath

define inspiratory reserve volume (IRV)

additional volume of air that can be taken in beyond normal tidal inhalation

define expiratory reserve volume (ERV)

additional volume of air that can be let out after normal exhalation

define residual volume (RV)

volume of air that remains in the lungs after a forceful expiratory effort

What is considered the top of a resting breath

in

what is considered the bottom of a resting breath

out

define inspiratory capacity (IC)

maximum amount of air that can be inhaled after normal tidal exhalation

What volumes make up the IC

TV + IRV

define functional capacity reserve/functional residual capacity (FCR)

the amount of air remaining in the lings at the end of normal tidal exhalation

What volumes make up the FCR

ERV+RV

define vital capacity

max amount of air that can be exhaled following a max inhalation

What volumes make up the VC

IRV+TV+ERV

define total lung capacity (TLC)

max volume to which the lungs can be expanded

What volumes make up the TLC

TV+IRV+ERV+RV

What is the typical TLC

5-6L

What percentage of the TLC is IRV

50%

What percentage of the TLC is TV

10%

What percentage of the TLC is ERV

20%

What percentage of the TLC is RV

20%

What is the purpose of the pulmonary function test (PFT)

can indicate type/progression/reversibility of disease

What is important for us to keep in mind when running a pt through PFT

make sure they are giving appropriate effort

how many attempts does the pt have to perform the PFT

3

What is FEV1

forced expiratory volume in 1 sec

instructions to give pts for the PFT

keep lips tight over mouth piece

breath in as much as you can

then breath out as fast as you can

then breath in again

What does a PFT graph look like

What is the importance of the FEV1/FVC ratio

can show us potential pathology

What are the types of pathology

obstructive, restrictive, combined

What does a PFT graph look like for obstructive pathologies

large volume (wide), with delayed expiration (concave)

What does a PFT graph look like for restrictive pathologies

very small volume, but shape appears normal

What does a wheeze sound like

high pitched, musical

What causes a wheeze sound

airway obstruction/narrowing

What pathology correlates to wheeze

asthma

What does a rhonchi sound like

low pitched and potential gurgle (snoring)

What causes a rhonchi sound

secretions

What pathology correlates to rhonchi

COPD, Bronchitis

What does a pleural friction rub sound like

low/deep grating (sand paper)

What causes pleural friction rub sounds

inflammation

What pathology correlates with pleural friction rub

pleuritis

What does stridor sound like

barking cough with potential wheeze (seal)

What causes stridor sound

obstruction/foreign body

what do crackles sound like

bubbling, popping

What cause course crackle sound

excessive fluid

What causes fine crackle sound

small airway disease

What pathology correlates with crackles

PNA, pulmonary edema, ARD, HF

What is the main cause of Kussmaul breathing

diabetic ketoacidosis

WHen is Cheyne-stokes breathing seen

in sleep apnea or toward the end of life

Describe Cheyne-stokes breathing

slow → rapid → no breathing

Decribe Biot’s breathing

no breaths followed by irregular/rapid breaths

describe Kussmaul breathing

rapid, deep, labored breathing