PATH 3610 Lecture Notes - Lecture 24: Acute Respiratory Distress Syndrome, Interstitial Lung Disease, Airway Obstruction
19 Dec 2016
School
Department
Course
Professor
1
Principles of Respiratory Disease
• Respiratory anatomy and function
• Edema
• Lung defences, bacterial pneumonia, & tuberculosis
• Alveolar injury: interstitial pneumonia and the acute
respiratory distress syndrome
• Airway diseases: infectious, asthma, COPD
• Lung Cancer
Anatomy of the Respiratory System
• Nasal cavity, larynx,
trachea
• Bronchi, bronchioles
– Air conduction
– Warming and
humidification
– Removal of
particles
• Alveoli
– Gas exchange
2
Ventilation of the lung
§ 10,000 litres of air daily
§ 300,000,000 alveoli
§ 80 m2
§ 1 tennis court
Matt Danko
Bronchiole
Perfusion of the lung
§ 1 blood volume (5 L) every minute
§ Capillary transit time : 0.75 seconds
(0.25 seconds required for O2 exchange)
Cor pulmonale
Bronchiole
PA
Bronchiole
PA
Pulmonary Functions
• Oxygen absorption & CO2 removal
– Ventilation (brain, muscles, airways, compliance)
– Gas exchange across the air-blood barrier
– Perfusion
• Defence
against airborne
micro-organisms
• Biotransformation,
endocrine functions
-huge number of alveoli in our lungs - very very small
-also a huge surface area- can be very vulnerable
PA- pulmonary artery
-no slack w/in the system -- every second matters
-if you develop lung disease it can lead to problems in the heart (one
side of the heart has to pump harder)
-3 steps
-toxic lung diease is a bigger issue in humans than domestic animals
3
Pulmonary disease causes failure of lung function
1. Arterial blood gas analysis
• ↓ paO2 : hypoxemia
• ↑ paCO2 : hypercapnea
2. Ventilation mechanics:
airflow & volume measured
using a spirometer
http://www.med-electronics.com
Kevin Doerschug, University of Iowa
Lung Function: Ventilation Mechanics
• Forced vital capacity: total volume of exhaled air
• FEV1: forced expiratory volume in 1 second
Flow (litres/second)
Volume (litres)
Normal
FEV1
spirometer measures
airflow & volume
Flow (litres/second)
Volume (litres)
Severe airflow obstruction
Expiratory time= 11 seconds
FEV1
Principles of Respiratory Disease
• Respiratory anatomy and function
• Edema
• Lung defences, bacterial pneumonia, & tuberculosis
• Alveolar injury: interstitial pneumonia and the acute
respiratory distress syndrome
• Airway diseases: infectious, asthma, COPD
• Lung Cancer
1.measure levels of O2 and CO2 in the blood
-if it is the barrier to the blood it is O2
-problems with ventilation (in and out) deals with both
FEV1- most of the volume is blown out in the first second - important
perimeter
-can compare to people with asthma and see how much lower FEV1 is
(unable to get air out of the lungs affectively)
Document Summary
Anatomy of the respiratory system: nasal cavity, larynx, trachea, bronchi, bronchioles. Huge number of alveoli in our lungs - very very small. Also a huge surface area- can be very vulnerable. Capillary transit time : 0. 75 seconds (0. 25 seconds required for o2 exchange) No slack w/in the system -- every second matters. If you develop lung disease it can lead to problems in the heart (one side of the heart has to pump harder) Pulmonary functions: oxygen absorption & co2 removal. Perfusion: defence against airborne micro-organisms, biotransformation, endocrine functions. Toxic lung diease is a bigger issue in humans than domestic animals. 1. measure levels of o2 and co2 in the blood. If it is the barrier to the blood it is o2. Problems with ventilation (in and out) deals with both. Arterial blood gas analysis: pao2 : hypoxemia, paco2 : hypercapnea. Ventilation mechanics: airflow & volume measured using a spirometer.
