Respiratory Failure & Intubation (Wk1) Flashcards
(53 cards)
What 2 things does the respiratory system consist of?
- a ventilatory pump
- a gas exchanging organ
what are the 2 main things of the ventilatory pump?
respiratory muscles and thorax
what organ is the ‘gas exchanging organ’ of the respiratory system?
the lungs
what happens when the ventilatory pump/ gas exchanging organ fail?
respiratory failure
does the pump failing indicate a CO2 movement problem or O2?
CO2
does the lungs failing indicate a CO2 or O2 movement problem?
O2
define respiratory failure
syndrome in which the respiratory system fails in one/ both of its gas exchange functions
what are the gas exchange functions of the respiratory system?
oxygenation & carbon dioxide elimination
4 types of respiratory failure
- hypoxemic
- hypercapnic
- acute
- chronic
Hypoxemia?
less oxygen in the body/ O2 movement problem
What are the PaO2 values in hypoxemic respiratory failure?
<60 mmHg on room air
—-> normal = >80mmHg
PaCO2 levels in hypoxemic RF?
normal/ low
why are the PaCo2 levels normal / low in hypoxemic RF?
if there is less O2 in the body being diffused to tissues and cells, there is less gas exchange occurring and l…
what does hypoxemia mean? (4)
- lung failure
- O2 gas movement issue
- reduced regional ventilation
- lung disease which is severe enough to interfere with O2 exchange e.g. ILD
Signs and symptoms of Acute Hypoxaemia
- dyspnoea
- changes in pattern of breathing (e.g. increase RR)
- agitation followed by drowsiness
- decreased mental acuity (PaO2 <40-50 mmHg)
- organ failure e.g. renal failure, brain injury
What is PaO2?
the partial pressure of oxygen in the arterial blood
is the PaO2 high or low in hypercapnic RF?
low
Is the PaCo2 high or low in hypercapnic RF?
high - > 50 mmHg
(normal = 35-45mmHg)
Hypercapnic RF means…
- pump failure
- primarily a CO2 gas movement issue
- reduced alveolar ventilation (can’t blow off CO2 to get in O2)
- pump = inadequate and cannot maintain ventilation to eliminate the CO2 produced by metabolism
- PaO2 will be low as well, since inadequate fresh gas enters the lungs (CO2 cant be blown off so O2 cant be inspired)
Signs and symptoms of Acute Hypercapnia
- dyspnoea
- Increased RR / change in POB
- agitation, tremor
- confusion –> coma
- increased ICP (CO2 does that), headache
what do the symptoms of hypercapnia depend on?
- rate of rise of CO2
- extent of metabolic compensation
Acute RF
- rapid onset, short course
- pronounced symptoms & can be life threatening
Chronic RF
- long duration of poor ABG values (days –> months)
- will be (metabolic) compensation, therefore pH can be normal
acute on chronic
e.g. acute exacerbation of COPD