respiratory disorder Flashcards
what is dyspnea?
subjective sensation of uncomfortable breathing
what are the four different types of dyspnea and what do they mean?
- severe dyspnea = flaring of nostrils, use of accessory muscles and retraction of intercostal spaces
- dyspnea on exertion = shortness of breath with activity
- orthopnea = shortness of breath when lying down
Paroxysmal nocturnal dyspnea = waking at night and gasping for air (must sit up/ stand)
what does paroxysmal mean?
sudden increase or reoccurrence of symptoms
Define a cough?
- a protective reflex that helps clear the airways by an explosive expiration
distinguish the difference between an acute and a chronic cough
acute = resolves within 2-3 weeks chronic = lasts longer than 3 weeks
why is it important to recognise abnormal sputum and what do you look for?
- can tell you about the progression of a disease or the effectiveness of the therapy
- look for changes in consistency, colour, amount and odour
define hemoptysis
coughing up blood or bloody secretions
define eupnea
normal breathing pattern
what are abnormal breathing patterns
adjustments made by the body to minimise the work of respiratory muscles
what are Kussmaul respirations
- slightly increase ventilatory rate, very large tidal volume and no expiration pause
- can have a fruity acetone on breath
define laboured breathing
increased work of breathing
describe a cheyne-stokes breathing pattern
- rapid breathing then stop (ventilations increase in volume until peak is reached and then apnea lasts between 15 to 60 seconds, process repeats)
- near death breathing pattern
define bradypnea
slow breath rate
define biots
an irregular breathing pattern
define restrictive breathing
disorders that stiffen the lungs or chest walls to decrease compliance
what is cyanosis and why does it develop?
- blueish purple discolouration of skin and mucous membranes
- develops when you have 5 grams of desaturated haemoglobin regardless of concentration
distinguish the difference between peripheral and central cyanosis ( where they are best seen and primary cause)
- peripheral = normally due to poor ciculation and best seen in the nail beds
- central = normally due to decreased arterial oxygenation ( low spo2) and best observed in buccal membranes and lips
define clubbing and what causes it?
- enlargement in tips of fingers and change in angle of nail bed
- associated with many lung diseases due to decrease oxygen in blood
in relation to the V/Q ration what does the v and q mean and what is the normal ratio?
- V = ventilation (the amount of air reaching the aveoli)
- Q = Perfusion (amount of blood reaching the aveoli)
- normal perminute ration is 0.8 - 0.9
what happens if there is a ventialtion - perfusion ration mismatch
- results in hypoxemia ( low levels of oxygen in the blood)
what does a low V/Q mean and what happens
- imparied gas exchange and results in low PaO2
what does a high V/Q mean and what happens
- occurs in pulmonary embolism (blood clot in lungs) and results in a low PaO2
what are the three things pulmonary function tests do
- assess lung function
- determines fitness
- detects impairment
define hypercapnia and why it might happen
- increase in CO2 in arterial blood
- occurs from decreased drive to breath or inadequate ability to respond to ventilatory stimulation
define hypoxemia
low levels of O2 in blood
define hypoxia
low leveles of O2 in tissues
what is the most common cause of both hypoxia and hypoxemia
ventilation - perfusion ration abnormalities
how would yu test for hypercapnia, hypoxia, hypoxemia
blood gases
what do ventilatory function test look at and what is the common tool used
- they measure lung volumes and pressures
- spirometre
what doe FEV1 mean?
- forced expiratory volume in one second
what does FVC mean ?
- forced vital capacity
what is considered the normal FEV1/FVC and what factors contribute to this
- normal value = 80%
- normal ranges are dependant on age, sex, height and ethnicity
what can impact the ventilatory function tests and what can the abnormal values generated tell us
- obstructive and restrictive respiratory defects will impact values
- the values can indicate if defect is restrictive or obstructive
what is a restrictive defect and what will the values on the ventilatory tests show and provide an example
- defects that decrease the compliance of the lungs or chest wall Ventilatory test outcomes : FEV1 = slighlty reduced FVC = decreased proportionally to FEV1 FEV1/FVC= normal (80%) - asbestosis
what is an obstructive defect and what will the values on th ventilatory test show and what is an example
- defects that block the exchange of air to and from lungs
ventilatory test outcomes:
FEV1 = greatly reduced
FVC= normal or slightly decreased
FEV1/FVC = below 80% (normal) - copd - emphysema and chronic bronchitis
