What is COPD?
Chronic Obstructive pulmonary disorder
- A progressive chronic lung diseases that limit air flow and gas exchange
What is chronic bronchitis characterised by?
- chronic inflammation of bronchi
- excess mucus production
- chronic productive cough
- blue bloaters
How is emphysema characterised?
- abnormal permanent enlargement of the airsick distal to terminal bronchioles due to damage to alveolar walls (air sacs) within the lung
- pink puffers
Name 3 causes of COPD
- smoking
- LT exposure to industrial pollution, indoor air pollution
- chemical fumes
- genes
What is type 1 respiratory failure?
- failure in O2 exchange, hypoxemia, most common with acute lung diseases e.g pulmonary oedema and pneumonia.
What is type 2 respiratory failure?
-hypercapnia- body cannot remove carbon dioxide from the body
Name 3 causes of type 2 respiratory failure
- Drug overdose
- chest wall abnormality
- COPD
- severe asthma
Type 2 respiratory failure:
- Should PaCO2 be more or less than 6.7kPa?
- What should normal PaCO2 levels be?
- More
- 6.0kPa
What is meant by a V/Q mismatch?
When a part of your lung receives oxygen without blood flow or blood flow without oxygen
What does ventilation mean in the V/Q ratio?
Ventilation- the volume of air you breathe in which moves into and out of the mouth
What does Perfusion mean in the V/Q ratio?
Perfusion- is defined as the flow of blood through tissues
If COPD affects ventilation, will the V/Q be low or high?
Low- can cause a mismatch between ventilation and perfusion
If heart failure affects perfusion will the V/Q be high or low?
High- can cause a mismatch between ventilation and perfusion.
V/Q mismatch in Asthma- When person is totally well, V/Q=1. As bronchospasm increases, less air gets to________, therefore V/Q<1. If the condition worsens and some airways become fully________ (bronchospasm plus excess mucus), V/Q= __
- alveoli
- closed
-0
What is a Shunt?
- where under-ventilated areas of the lungs can cause a shunt where venous blood returns to the heart without collecting its normal oxygen quota.
What conditions causes a shunt?
- Pneumonia
- Atelectasis- collapsed part of lung or lung
- Severe Pulmonary Oedema
What is the normal V/Q ratio?
0.8
When does a silent unit occur?
when little or no ventilation and perfusion are present, such as in the case of pneumothorax and (ARDS) Acute Respiratory Distress Syndrome
What does Left Ventricular Failure cause?
- Causes blood to back-up pulmonary veins into lungs, causing fluid to build up into lungs (pulmonary oedma)
Name 5 Symptoms of Pulmonary Oedema
- SOB
-DIB
-anxiety - Pale
-Pink frothy sputum
-Hypoxia - Peripheral Oedema
-Orthopnoea (inability to lie flat down due to breathlessness)
What is ARDS?
- a form of non-cardiogenic pulmonary oedema that can quickly lead to acute respiratory failure
- a result of acute lung injury- which leads to increased vascular permeability causing pulmonary oedema
- characterised by acute, severe hypoxia which is not caused by left ventricular failure.
Name 5 direct injuries that cause ARDS
- pneumonia
- aspiration of gastric secretion
- drowning
- PE
- Trauma (severe chest injury)
- inhalation injury (e.g smoke inhalation)
Name 4 indirect injuries that cause ARDS
- Sepsis
- massive blood transfusion reaction
- acute pancreatitis
- severe burns
What is the exudative phase of ARDS?
- first 24hrs, with hyperaemia.
- leakage of fluid into the alveoli plus haemorrhage and infiltration of neutrophils.
