Week 4 ABG Review Flashcards
Test to measure the acidity (ph), the levels of oxygen O2, carbon dioxide (CO2), and bicarbonate (HCO3) in the blood.
ABGs ( Arterial Blood Gases)
- Used to provide diagnosis and to guide therapy in ill patients.
Acid/ Base Numbers of HCO3
22-26 mEq/L
pH level is
7.35-7.45
PaCO2 is
35-45 mm Hg
PaO2 80-100 mm Hg
True
Oxygen saturation is above
94%
The kidneys regulate arterial HCO3 by reabsorbing what?
Filtered bicarbonate and replacing bicarbonate lost in buffering acids
Lungs regulate what?
CO2 via the medulla
Name the components of ABG
- pH - portrays acid or alkaline balance of the blood
- PCO2- Amount of CO2 dissolved in the blood plasma
- HCO3- Amount of bicarbonate (base) in the blood
pH portrays the what?
Acid or alkaline balance of the blood
Normal 7.35-7.45
pH less than 7.35 is an acid condition
7.45 the body is what? Alkaline state.
PCO2 is what?
Amount of CO2 dissolved in the blood
When CO2 is combined with H2O becomes what?
Carbonic Acid
Therefore is considered an acid
Normal range of CO2 is
35-45
PCO2 is regulated by what?
Lungs and respiratory
If CO2 is above 45 an acid condition exists
If CO2 is below 35 then it is an alkaline condition exists
HCO3 is amount of bicarbonate in the blood
True
Normal range for HCO3 is
22-26
Influenced by metabolic system
What is regulated by the renal system?
HCO3
Acid condition exists if < 22 (deficiency of base products)
True
Alkaline condition exists if
> 26 too much base
Respiratory acidosis occurs with what?
Hypoventilation (retain CO2)
- Overdose of narcotics
- COPD
- Neuromuscular disorders
Respiratory insufficiency there will be signs of what?
- SOB
- Cyanosis
a
Name the causes of Respiratory Alkalosis
- Fear/ Pain
- Large Tidal Volume
- Increased respiratory rate
This occurs when body gains acid or loses base thus decreasing HCO3 <22
Metabolic Acidosis
Name the causes of loss of lower GI fluids
Diarrhea
- Pancreatic Drain
- Kidney Failure
Name the symptoms of metabolic acidosis
- Deep and fast breathing
- Disorientation
- Coma
This occurs when body loses acid or gains base, thus increasing the HCO3 > 26.
Metabolic Alkalosis
Name the causes of Metabolic Alkalosis
- NG suction
- Vomiting
- Overuse of antacids
Name the symptoms of Metabolic Alkalosis
Mental confusion
Apathy
Weakness
Dizziness
What is compensation?
Body’s attempt to maintain the pH within normal limits
Name the 3 degrees of compensation
- Complete Compensation
- Partial Compensation
- No compensation
The respiratory system attempts to do what to compensate for metabolic disorders
- Responds within minutes
- Increase rate and depth of breathing
The metabolic system attempts to compensate for respiratory abnormalities
True
1. Slow and may take 24-48 hr
2. Kidneys save HCO3 which increases the pH
3. When pH normal, compensation complete
What is complete compensation?
Occurs when the pH value returns to normal
In complete compensations both what will be abnormal?
PCO2 and HCO3
One value will be abnormal as it is causing the disorder
2nd value will become abnormal in compensation for the imbalance
In partial compensation what is not yet within normal limits?
pH
What is all abnormal in partial compensation?
pH, PCO2, and HCO3
One value abnormal as it is causing the disorder
2nd value abnormal as it attempts to compensate for the disorder
True
In no compensation the pH will be what?
Abnormal
With metabolic disorder the HCO3 will be?
Abnormal and the PCo2 will be normal
With respiratory disorder the PCO2 will be
Abnormal and the Hco3 will be normal
Step 1 in ABG is
Determine if pH is acid or alkaline
if pH is less than .35 it is
Acid condition exists
7.35- 7.40 is
Normal but on low (acid) side of normal
If pH is 7.40-7.45 it is normal but on high (alkaline) side of normal
True
If the pH is 7.45 above
Alkaline condition exists
- record value and write whether it is normal, acid or alkaline
What is step 2 of ABG?
Determine if PCO2 ACID (high) or Alkaline (low)
Step 2 of ABG includes
- Evaluate the respiratory system by assessing the PCO2
- If PCO2n> 45 an acid condition exists
- If PCO2 <35 an alkaline condition exists
- Record the PCO2 value and write beside the value whether it is normal, acid, or alkaline
Step 3 of ABG is
Determine if HCO3 is acid (low) or Alkaline (high)
Step 3 of ABG includes
- Evaluate
- The metabolic system by assessing the HCO3 level - Base
- If <22, base products low and acid condition exists - Excess
- If >26, excess of base products cause and alkaline condition - Record
- Record the HCO3 value and write beside the value whether it is normal, acid, or alkaline
What is step 4 of ABG?
Compare the pH with the metabolic HCO3 or resp. CO2
Step 4 ABG includes
- Look at condition(Normal, Acid or Alkaline) was written beside pH
- Determine which system (Metabolic HCO3) or (Respiratory PCO2) has the same condition
- The system that has the same condition as the pH is the one causing the imbalance
Step 5 of ABG is
Once pH has been matched with the system causing the disorder, look at te value of the other system to determine the status of compensation
