ABG's Flashcards
What are ABG’s used for?
To assess patients for respiratory failure and for monitoring in ITU
What ‘lines’ are used to take blood in order to measure blood gases? (Patients usually have these on ITU)
Arterial lines either in radial or femoral arteries
What is usually measured when reading ABG’s? (6 answers)
- Acid base balance
- Blood gases (PaO2, PaCO2)
- Bicarbonate (HCO3)
- Lactate
- Haemoglobin
- Electrolytes
What is the normal values of pH?
7.35 - 7.45
What are the normal values of PaO2?
10.7 - 13.3 kPa
What are the normal values of PaCO2?
4.7 - 6 kPa
What are the normal values of HCO3?
22 - 28mmol/L
What are the normal values of the Base excess?
-2 - +2
What are the normal values of lactate?
0.5 - 1 mmol/L
What are the normal values of haemoglobin?
Male - 13.7 - 17.5
Female - 12.0 - 15.5
What are the normal values of WBC’s?
3.5 - 10.5
What is the FiO2 percentage of room air?
21%
A nasal cannula supplying 1L of O2 has a FiO2 of what percentage?
24%
A nasal cannula supplying 2L of O2 has a FiO2 of what percentage?
28%
A nasal cannula supplying 3L of O2 has a FiO2 of what percentage?
32%
A nasal cannula supplying 4L of O2 has a FiO2 of what percentage?
36%
How many litres of O2 is effective when using nasal cannula for supplementation?
4L
What oxygen mask could be used to accurately provide FiO2 for a patient with COPD?
Venturi mask
A simple mask supplying 5L of O2 has a FiO2 of what percentage?
40%
A simple mask supplying 6L of O2 has a FiO2 of what percentage?
44%
A simple mask supplying 7L of O2 has a FiO2 of what percentage?
48%
A simple mask supplying 8L of O2 has a FiO2 of what percentage?
52%
A simple mask supplying 9L of O2 has a FiO2 of what percentage?
56%
A non rebreather mask supplying 10L of O2 has a FiO2 of what percentage?
95%
What classifies respiratory failure type 1?
PaO2 < 10.7kPa
What classifies respiratory failure type 2?
PaO2 < 10.7kPa
PaCO2 > 6kPa
What classifies hypercapnia? (PaCO2 figure)
PaCO2 > 6kPa
What classifies respiratory acidaemia?
pH < 7.35
PaCO2 > 6kPa
What classifies respiratory alkalemia?
pH > 7.45
PaCO2 < 4.7 kPa
What are the causes of respiratory alkalemia?
Hyperventilation and pulmonary embolism
What are the acute causes of respiratory acidaemia? (5 answers)
Asthma
COPD
Emphysema
Sleep apnoea
Pneumonia
What does CO2 become when dissolved in H2O?
Carbonic Acid
Which organ creates bicarbonate or HCO3?
Kidneys
What is the role of bicarbonate or HCO3?
Acts as a buffer to neutralise pH levels in blood
What is the role of haemoglobin?
Transportation of oxygen from lungs to tissue via blood
What is the main function of a WBC?
Respond/combat infection
What is the role of platelets in the blood?
Involved in activation of clotting process
What are normal platelet values?
150 - 400
What are the 3 main causes of thrombocytopenia? (low platelets)
Not enough platelets are not made in the bone marrow
Increased breakdown of platelets in the bloodstream
Increased breakdown of platelets in the spleen or liver
What classifies metabolic alkalemia?
pH > 7.45
HCO3 > 28
What classifies metabolic acidaemia?
pH < 7.35
HCO3 < 22
What are the causes of metabolic acidaemia?
> H+ ions (renal failure)
< HCO3 (diarrhoea + renal failure)
What are the causes of metabolic alkalosis? (2 answers)
Gastroenteritis (vomiting + loss of acid)
Aldosterone (fluid retention + maintainin H+ions)
What is the main cause of WBC’s to fall below 3.5?
Suppression of the immune system
What causes WBC’s to be above 10.5? (3 answers)
Infection
Post exercise
Stress
What is the role of the kidneys in acid-base balance? (2 answers)
They reabsorb bicarbonate from urine.
They excrete hydrogen ions into urine.