Acid/ Base Management Flashcards
(158 cards)
base excess refers to a patient’s (metabolic/ respiratory) acid/base status
metabolic
What does base excess tell us clinically?
an ABG value that reveals if patient has too much or too little base in the blood
Normal base excess
-2 to 2 mmol/L
What is negative base excess value?
What does it mean?
How do you treat it?
below -2mmol/L
there is not enough base in the body; metabolic acidosis
treated with bicarb
What is a positive base excess value?
What does it mean?
How do you treat it?
above 2mmol/L
there is too much base in the body; metabolic alkalosis
treated by reversing the cause of alkalosis
A high concentration of H+ ions will = (high/low) pH?
low= acidotic (acid)
a low concentration of H+ ions will = (high/low) pH?
high= alkalosis (basic)
What is the normal pH range?
7.35-7.45 (7.4)
pH > 7.45 = (acidosis/alkalosis)?
alkalosis
pH < 7.35= (acidosis/alkalosis)?
acidosis
What is pH determined by?
HCO3-/ PaCO2 ratio
6 consequences of Acidosis:
- contractility?
- catecholamines?
- bleeding?
- vasculature?
- arrythmias?
- ion concentrations?
- decrease cardiac contractility
- decrease the response to catecholamines
- impair coagulation and increase bleeding
- increase PVR
- Makes Vfib more likely
- increases plasm K+
- H+ enters the cell and K+ exits
5 consequences of Alkalosis:
- hemoglobin?
- vasculature? (3)
- ion concentrations?
- Shifts the oxyhemoglobin dissociation curve to the left
- hemoglobin will bind oxygen more tightly - increase SVR
- Cerebral vasoconstriction
- because of the left shift of the oxyhemoglobin curve - Decreases PVR
- decreases plasma K+ concentration
- H+ exits the cell and K+ enters
What is a normal venous CO2 measurement?
24-30 mEq/L
*includes both the CO2 dissolved in plasma and the HCO3- dissolved in plasma
What is a normal arterial HCO3- measurement?
22-26 mEq/L
normal PaCO2
35-45 mmHg
normal PvCO2
40-50 mmHg
~5 mmHg higher than PaCO2
What does the PaCO2 and PvCO2 gradient tell you about your patient?
If the PaCO2 and PvCO2 gradient increases, the patient is poorly perfused
PaO2 of the atmosphere (at sea level)
160mmHg
-O2 makes up 21% of atmospheric pressure 760mmHG
normal PaO2
70-100 mmHg
-decreases with age
normal PvO2
30-40mmHg
normal CaO2
16-20 mL/ dL
normal CvO2
12-16 mL/dL
normal DO2 (total delivery of oxygen per minute)
1000 mL of oxygen delivered per minutes
*assumes normal hemoglobin (15g/dL), normal SaO2 of (97.5%), and normal cardiac output (5 L/min)