Exam 1 Flashcards
Physiologic criteria for ABG selection
Allens test, accessibility and size of artery, proximity of surrounding structures
Help breakdown blood clots already formed
Thrombolyics
What happens to PaCO2 when deadspace decreases
Decreases
How long should you wait before sampling an ABG after a change in oxygen therapy or ventilation?
20-30 mins
Decreased pH in the blood
Acidemia
The indisputable gold standard for eval of arterial oxygenation
ABGs
The most sensitive indicator of oxygenation directly measured
PaO2
PaCO2 <35
Hypocapnia
Normal range: SaO2
95-100%
How is SaO2 measured?
Infared light
Normal venous HCO3
24
What do air bubbles effect?
PaO2
Normal COHb
<6%
Normal HCO3
24
Increase pH in the blood
Alkalemia
A proton donor
Acid
Normal venous PO2
40
What does COHb measure?
Hb CO binding
The electrode that measures PaCO2
Severinghaus
The most important value when getting an ABG
PaCO2
A proton acceptor
Base
Increased pH in the tissue
Alkalosis
Normal range pH
7.35-7.45
Normal venous BE
0
What occurs if PaO2 is <80?
Hypoxemia
Normal venous pH
7.35
Normal venous SO2
70-75%
60-79
Mild hypoxemia
What does hypocapnia indicate?
Hyperventilation
40-59
Moderate hypoxemia
What happens to PaCO2 when RR and VT are both decreased?
Increases
What does hypercapnia indicate?
Hypoventilation
<40
Severe hypoxemia
What happens to PaCO2 when deadspace increases?
Increases
Only calculated when ABG machine doesn’t have co-ox
SaO2
What happens to PaCO2 when RR and VT both increase?
Decreases
Given to prevent blood clots
Anticoagulants
How long should you hold after sticking patient on an anticoagulant?
5-10 mins
PaCO2 >45
Hypercapnia
List all measured values
pH, SaO2, PaO2, PaCO2, COHb
What does the PaCO2 measure?
Ventilation
If the PaCO2 is >45 what would you do to the patient?
Put them on the vent
Normal venous PCO2
46
Normal range PaO2
80-100
Normal PaO2
90
The electrode that measures PaO2
CLARK
What does the PaO2 measure?
Oxygenation
The electrode that measures pH
SANZ
Normal pH
7.40
Normal BE
0 +- 2
Two indices that basically reflect the amount of O2 present in the blood
PaO2, SaO2
How O2 is carried in the blood
dissolved O2, combine O2
List all calculated values
HCO3
Calculating PaO2 vs age
109 - (.43 x age)
What does SaO2 measure?
Hb efficiency O2
What occurs if PaO2 is >100?
Hyperoxygenation
Normal PaCO2
40
Normal range HCO3
22-26
What does HCO3 calculate?
Acid-base status
Complications of ABGs
Hematoma, infection, pain
What does the pH measure?
Acid-base status
Normal range PaCO2
35-45
Decreased pH in the tissue
Acidosis
How is COHb measured?
Infared light
Generally runs on the lower side with women
PaCO2