ABG and Gas exchange Flashcards
On average, how much CO2 do we produce
200mL/min
What creates CO2 in the body
metabolism of carbs and fats
*combines h20 and h2co3
What organ makes bicarb
kidneys
Why do kidneys make bicarb
to buffer acids (more alkaloid)
For every HCO3 made by the kidneys, how much H+ is eliminated
one
What occurs in the body if someone is severely acidodic
hyperkalemia
-decreased CO
-vasodilation
-increased ectopic rhythms
-Right shift
What occurs in the body is someone is alkalotic
Decrease of protons pushed into the cell
-causing excitability
-ventricular tachyarrhythmias
-SVT
-Hypokalemia
-Left shift
What happens if there is a decrease in protons being pushed into cells
calcium and mag are not pushed out of the cell, so there is a drop in ECF (extra cellular fluid)
What is the make up of the buffering system
weak acid
conjugate base
What pH is not compatible with life
6.1
What is the pH if CO2 and HCO3 are equal
6.1
Besides Renal and CO2, what are the other buffering systems
hemoglobin
phosphate
plasma proteins
Where is a hemoglobin buffer found
intracellularly
When is a hemoglobin buffer preferred
is there is low venous O2
What is HHB
deoxyhemoglobin
What environment is HHbCO2 formed
acidic environment
What is carboxyhemoglobin
carbon monoxide on hemoglobin
what is an ionic shift
H+ is exchanged for K+ across cellular membrane
What is the hallmark for respiratory acidosis
increase PaCO2
What is the hallmark for respiratory alkalosis
decreased PaCO2
What characteristics make up metabolic acidosis
pH < 7.4
all systems effected except respiratory
What is the hallmark for metabolic alkalosis
increased serum HCO3
When is anion gap looked at
in patients for pH disorders
What is seen with an anion gap
the difference between cations and anions (ABG and CMP)
What may make SaO2 readings inaccurate
anemia
poorly adhered probe
nail polish
carbon monoxide poisoning
tachypnea
dehydration
darker skin color
What makes up reserve volumes
inspiratory and expiratory
What are the lung volumes
tidal volume
reserve volume
residual volume
What are the different lung capacities
inspiratory capacity
expiratory capacity
vital capacity
total lung capacity
functional capacity
What are the stretch receptors activated in the lungs
the TV > 800mL
What is tidal volume
amount of air that can be inhaled or exhaled in one respiratory cycle
includes the volume to fill physiologic dead space
What the the equation for minute ventilation
MV = TV x RR
What is inspiratory reserve volume
Amount of air that can be forcibly inhaled after tidal volume (amount in deep breath)
What is a normal inspiratory reserve volume
1900 - 3300mL
What is expiratory reserve volume
amount of air that can be forcibly exhaled beyond tidal volume
(amount in full exhale)
What is normal expiratory volume
700 - 1200mL
What is residual volume
amount of air that remains in the lungs after full exhale
What is normal residual volume
1200mL
What is the inspiratory capacity
total inspiratory volume
inspiration reserve + tidal volume
What is the total lung capacity
total volume of air the lungs can accommodate with maximal inspiration
What is normal total lung capacity
4-6L
What is vital capacity
total volume exhaled after full inhalation
What is normal vital capacity volume
4800mL
How does tidal volume compare to vital capacity
tidal volume is only 10% of vital capacity
What is functional residual capacity
air in the lungs after a typical exhalation (unforced)
What are PFTs utilized for
to diagnose restrictive and obstructive pulmonary disorders
*completed with spirometer
What is a normal FEV1 / FVC ratio
.8
What can cause acid - base issues in the body
respiratory acidosis
respiratory alkalosis
metabolic acidosis
metabolic alkalosis
