ABG Flashcards
PH range
7.35-7.45
CO2 range
35-45
HCO3 range
22-26
PaO2 range
80-100
SaO2 range
> 95%
Base (deficit/excess)
(-2) - (2+)
PH means
percentage of hydrogen ions
HCO3 means
sodium bicarbonate
H2CO3 means
carbonic acid
CO2 means
carbon dioxide
PaO2 means
partial pressure of oxygen
SaO2 means
oxygen saturation
PH is an inverse log of:
hydrogen ions
pCO2 means
partial pressure of carbon dioxide
CO2 exists in the blood as a:
CO2 is a normal byproduct of:
CO2 is an indicator of:
soluble gas
metabolism
acid
CO2 regulation is a function of:
minute volume
Minute volume=
tidal volume (Vt) x respiratory rate (F)
> 45 PH is:
<35 PH is:
acidotic
alkalotic
apnea/hypoventilation >45 PH
respiratory acidosis
hyperventilation <35 PH
respiratory alkalosis
HCO3 moves with
PH scale
<22 bicarbonate
metabolic acidosis
> 26 bicarbonate
metabolic alkalosis
as a buffer system how quickly does bicarb and carbonic acid respond?
seconds
as a buffer system how quickly do the lungs respond with holding/blowing off CO2?
minutes
as a buffer system how quickly do the kidneys resorb/excrete bicarb?
hours to days
A base deficit of ____ is an indicator for the potential need for blood transfusion
> -4
a base deficit of ____ correlates with a poor outcome (death likely)
> -19
bicarb replacement formula
0.1 x (-BE) x pt weight in Kg
PaO2 40/50/60 roughly equates too (in SaO2)
70/80/90%
Oxyhemoglobin dissociation curve
Left shift directions for:
affinity
H+
temp
2,3-DPG
PCo2
all low aside from affinity
Oxyhemoglobin dissociation curve
Right shift directions for:
affinity
H+
temp
2,3-DPG
PCo2
all high aside from affinity
is it respiratory or metabolic?
if CO2 follows PH=
respiratory
is it respiratory or metabolic?
if HCO3 follows PH=
metabolic
the compensatory mechanism is __________ the primary problem
opposite
respiratory acidosis is compensated by
HCO3 (bicarb)
metabolic alkalosis is compensated by
CO2 (acid)
if PH is outside normal values and both respiratory and metabolic are outside range it is _________ compensated
partially
if PH is inside normal values and both respiratory and metabolic are outside range it is _________ compensated
fully
acidotic abg ranges
PH <7.35
CO2 >45
HCO3 <22
alkalotic abg ranges
PH >7.45
CO2<35
HCO3 >26
Critical ABGs for intubation
PH <7.2
CO2 >55
PO2 <60
metabolic alkalosis
PH ___
bicarb ____
too little ____ or too much ____
> 7.45
26
H+
HCO3
vomiting, nasogastric suctioning, diuretics, corticosteroids, antacid poisoning, diamox usually causes:
metabolic alkalosis
metabolic acidosis
PH ____
bicarb ____
too much ___ or too little ___
<7.35
<22
H+
HCO3
1 cause of of metabolic acidosis is
lactic acidosis
evidenced by lactate >4
ketoacidosis, hyperthermia, fever, seizures, rhabdomyolisis usually causes
metabolic acidosis
Alveolar hyperventilation, ASA poisoning (respiratory center stimulant), hyperthermia/heat injury, hypermetabolic states, fever, anxiety, pain, pregnancy, high altitude usually causes
respiratory alkalosis
for respiratory alkalosis on a vent check ___ first and then ___
tidal volume (Vt)
rate (f)
chest wall injury, CNS depression, lung injury, rib fractures, COPD, asthma usually causes
respiratory acidosis
CO2 diffuses into circulation and is txptd to _______________
CO2 diffuses across _____________ into the alveoli
pulmonary capillaries
capillary/alveolar membrane
_________ increased to blow off CO2
minute volume
for every 10 mmHg change in ETCO2 expect the pH to change __ in the ______ direction
0.08
opposite
for every change of 0.15 in pH expect the HCO3 to change ____ in the ____ direction
10 mmol/L
same
for every change of 0.10 in pH the K+ will shift ___ in the _____ direction
0.6
opposite
