NURS4581
, ABGs; Student Success Review Session
Criteria for Abnormal ABG states (provide values) = what defines each illness state:
Metabolic Acidosis Respiratory Acidosis
pH; _______________
7 35. pH; _______________
. 35
7
CO2; ______________
normal CO2; ______________
over 45
HCO3; _____________
22 HCO3; _____________
normal
Metabolic Alkalosis Respiratory Alkalosis
pH; _______________
. 45
7 pH; _______________
. 45
7
CO2; ______________
normal CO2; ______________
less than 35
HCO3; _____________
22 HCO3; _____________
normal
What’s missing?
Oxygenation : low 02 causes m acidosis be lactic acid be cell androbic
_______________________________________________________
.
Criteria for compensated ABG:
________________________________________________________
normal pH altered CO2 or HCO3
,
(a) Interpret the blood gas.
compensated
___________ _____________________
respiratory acidosis
___________
pH 7.35 low
7 40
.
use ROME B
PaCo2 64 high
compensat somes
compare co2B
see
HCO3 to pH to
HCO3 30 high .
which It is
PaO2 82 normal . 35
7
7 . 45
(b) Which clinical manifestations are expected?
shallow B slow breaths alveolar
__________________________________________________________________
hypotension
,
(c) Priority management of respiratory acidosis? ________________________
treat the cause
(d) Nursing interventions that improve alveolar hypoventilation are _______?
___________________________________________________________________
deep breaths suction cough , sit up bronchodilators intubation
,
, , ,
,What acid-base imbalance exists?
pH 7.25
PaCo2 64 ↑
HCO3 20
SaO2 88% V
(a) Interpret the blood gas.
_______________
uncompensated Respiratory acidosis + metabolic
___________________________ acidosis +hypoxemia
___________
(b) List clinical manifestations from above ABG?
↓ LOC & hypotension (bc vasodilation) +
hyperkalemia
____________________________________________________________________
(c) List illnesses that can cause respiratory acidosis?
COPD stroke overdose respiratory failure
___________________________________________________________________
, , ,
(d) List illnesses that can cause metabolic acidosis?
DKA hypoxemia pneumonia BARDS
___________________________________________________________________
, ,
(a) Interpret the blood gas. ___________ metabolic alkalos is
__________ ___________
uncompensated
pH 7.49 ↑
PaCo2 42 norm
HCO3 32 ↑
SaO2 95% norm
(b) Which finding would the nurse expect to observe as the body compensates for the acid-
base imbalance?
shallow breaths
___________________________________________________________________________
(c) What treatment should the nurse anticipate for this acid-base imbalance?
Acetazolamide
____________________________________________________________________________
(d) Acetazolamide, a carbonic anhydrase inhibitor that promotes diuresis, was administered
to the patient. What would best indicate the effectiveness of the medication? _________
↓
pH BNHCO3
, pH 7.40
Acid: Base:
(7.35-7.45)
CO2 (PCO2 35-45 mm Hg) HCO3 (22-26 mEq/L)
“Just like our pH range of 7.35- “Golden years 22-26”
Acidosis |Alkalosis
7.45, but forget the ‘7’.”
Acidosis = caused by ↑CO2 ,
↑H+ or ↓HCO3
CO2 tells us about HCO3 tells us about
Alkalosis = caused by ↓CO2,
respiratory function. ↓H+, or ↑HCO3 metabolic function.
ROME: Respiratory Opposite, Metabolic Equal
In cases of compensation, the pH may not
Respiratory: be ↑/↓ outside of the 7.35-7.45 range, Metabolic:
↑CO2, ↓pH but look to see whether it is ↑ or ↓ from the pH 7.40 mark. ↑HCO3, ↑pH
↓CO2, ↑pH ↓HCO3, ↓pH
ABG Analysis Process: (p. 324 Lewis)
1. Label pH above 7.4 as alkalotic and below 7.4 as acidic.
2. Analyze PaCO2 to determine if imbalance is respiratory (label high CO2 acidic; low=alkalotic).
3. Analyze HCO3 to determine if imbalance is metabolic (label high HCO3 alkalotic, low=acidic).
4. If PaCO2 and HCO3 are both normal and pH is between 7.35-7.45, consider ABGs normal.
5. If both PaCO2 and HCO3 are altered, determine which matches the pH alteration. For example, a low pH you labeled “alkalotic” and an elevated
HCO3 you labeled “alkalotic” indicates metabolic alkalosis.
6. Is the body attempting to compensate? If the other gas parameter is moving in the opposite direction of the pH alteration (in the above example,
you may have an elevated/’acidic’ CO2 in addition to the elevated/‘alkalotic’ HCO3), this indicates a compensated imbalance.
Respiratory Acidosis Metabolic Acidosis
* Why? Anything decreasing rate or depth of respirations Why? Diabetics with excess ketones, renal failure can’t
write on (hypoventilation) à CO2 retention regulate HCO3/H, poisoning, diarrhea losing basic
cheat sheet Interventions? Increase rate or depth of respirations stool, anaerobic metabolism
Ask Hughes
-
Breathing? See slow RR or reg. rate with Interventions? treat underlying cause (give O2), give
what to write shallow/ineffective respirations sodium bicarbonate
Compensation: Metabolicàkidney ↑ HCO3 Compensation: Respiratory- deep or rapid (Kussmaul’s)
production OR ↓HCO3 removal in urine OR ↑ H+ respirations
removal in urine
S/S of Acidosis: Drowsiness, headache, depressed LOC or even coma, ↑K, ↓BP due to peripheral vasodilation
Respiratory Alkalosis Metabolic Alkalosis
Why? Hyperventilation, may be due to low O2 states Why? Over ingestion of base (antacids), vomiting/NG
Interventions? Slow breathing, rebreather/ paper bag suction losing stomach acid, diuretics increasing H+
or fix oxygenation problem excretion
Breathing? Deep and/or rapid – causing the problem Interventions? Treat underlying cause, Diamox –
Compensation: Metabolicàkidney ↓ HCO3 generic is Acetazolamide (HCO3 waster)
production OR ↑HCO3 removal in urine OR ↓ H+ Compensation: Respiratory- slow & shallow resp.
removal in urine
S/S of Alkalosis: Hypocalcemia (tingling fingers/toes, tetany, Chvostek’s, muscle cramping), ↓K, Nausea/vomiting
, ABGs; Student Success Review Session
Criteria for Abnormal ABG states (provide values) = what defines each illness state:
Metabolic Acidosis Respiratory Acidosis
pH; _______________
7 35. pH; _______________
. 35
7
CO2; ______________
normal CO2; ______________
over 45
HCO3; _____________
22 HCO3; _____________
normal
Metabolic Alkalosis Respiratory Alkalosis
pH; _______________
. 45
7 pH; _______________
. 45
7
CO2; ______________
normal CO2; ______________
less than 35
HCO3; _____________
22 HCO3; _____________
normal
What’s missing?
Oxygenation : low 02 causes m acidosis be lactic acid be cell androbic
_______________________________________________________
.
Criteria for compensated ABG:
________________________________________________________
normal pH altered CO2 or HCO3
,
(a) Interpret the blood gas.
compensated
___________ _____________________
respiratory acidosis
___________
pH 7.35 low
7 40
.
use ROME B
PaCo2 64 high
compensat somes
compare co2B
see
HCO3 to pH to
HCO3 30 high .
which It is
PaO2 82 normal . 35
7
7 . 45
(b) Which clinical manifestations are expected?
shallow B slow breaths alveolar
__________________________________________________________________
hypotension
,
(c) Priority management of respiratory acidosis? ________________________
treat the cause
(d) Nursing interventions that improve alveolar hypoventilation are _______?
___________________________________________________________________
deep breaths suction cough , sit up bronchodilators intubation
,
, , ,
,What acid-base imbalance exists?
pH 7.25
PaCo2 64 ↑
HCO3 20
SaO2 88% V
(a) Interpret the blood gas.
_______________
uncompensated Respiratory acidosis + metabolic
___________________________ acidosis +hypoxemia
___________
(b) List clinical manifestations from above ABG?
↓ LOC & hypotension (bc vasodilation) +
hyperkalemia
____________________________________________________________________
(c) List illnesses that can cause respiratory acidosis?
COPD stroke overdose respiratory failure
___________________________________________________________________
, , ,
(d) List illnesses that can cause metabolic acidosis?
DKA hypoxemia pneumonia BARDS
___________________________________________________________________
, ,
(a) Interpret the blood gas. ___________ metabolic alkalos is
__________ ___________
uncompensated
pH 7.49 ↑
PaCo2 42 norm
HCO3 32 ↑
SaO2 95% norm
(b) Which finding would the nurse expect to observe as the body compensates for the acid-
base imbalance?
shallow breaths
___________________________________________________________________________
(c) What treatment should the nurse anticipate for this acid-base imbalance?
Acetazolamide
____________________________________________________________________________
(d) Acetazolamide, a carbonic anhydrase inhibitor that promotes diuresis, was administered
to the patient. What would best indicate the effectiveness of the medication? _________
↓
pH BNHCO3
, pH 7.40
Acid: Base:
(7.35-7.45)
CO2 (PCO2 35-45 mm Hg) HCO3 (22-26 mEq/L)
“Just like our pH range of 7.35- “Golden years 22-26”
Acidosis |Alkalosis
7.45, but forget the ‘7’.”
Acidosis = caused by ↑CO2 ,
↑H+ or ↓HCO3
CO2 tells us about HCO3 tells us about
Alkalosis = caused by ↓CO2,
respiratory function. ↓H+, or ↑HCO3 metabolic function.
ROME: Respiratory Opposite, Metabolic Equal
In cases of compensation, the pH may not
Respiratory: be ↑/↓ outside of the 7.35-7.45 range, Metabolic:
↑CO2, ↓pH but look to see whether it is ↑ or ↓ from the pH 7.40 mark. ↑HCO3, ↑pH
↓CO2, ↑pH ↓HCO3, ↓pH
ABG Analysis Process: (p. 324 Lewis)
1. Label pH above 7.4 as alkalotic and below 7.4 as acidic.
2. Analyze PaCO2 to determine if imbalance is respiratory (label high CO2 acidic; low=alkalotic).
3. Analyze HCO3 to determine if imbalance is metabolic (label high HCO3 alkalotic, low=acidic).
4. If PaCO2 and HCO3 are both normal and pH is between 7.35-7.45, consider ABGs normal.
5. If both PaCO2 and HCO3 are altered, determine which matches the pH alteration. For example, a low pH you labeled “alkalotic” and an elevated
HCO3 you labeled “alkalotic” indicates metabolic alkalosis.
6. Is the body attempting to compensate? If the other gas parameter is moving in the opposite direction of the pH alteration (in the above example,
you may have an elevated/’acidic’ CO2 in addition to the elevated/‘alkalotic’ HCO3), this indicates a compensated imbalance.
Respiratory Acidosis Metabolic Acidosis
* Why? Anything decreasing rate or depth of respirations Why? Diabetics with excess ketones, renal failure can’t
write on (hypoventilation) à CO2 retention regulate HCO3/H, poisoning, diarrhea losing basic
cheat sheet Interventions? Increase rate or depth of respirations stool, anaerobic metabolism
Ask Hughes
-
Breathing? See slow RR or reg. rate with Interventions? treat underlying cause (give O2), give
what to write shallow/ineffective respirations sodium bicarbonate
Compensation: Metabolicàkidney ↑ HCO3 Compensation: Respiratory- deep or rapid (Kussmaul’s)
production OR ↓HCO3 removal in urine OR ↑ H+ respirations
removal in urine
S/S of Acidosis: Drowsiness, headache, depressed LOC or even coma, ↑K, ↓BP due to peripheral vasodilation
Respiratory Alkalosis Metabolic Alkalosis
Why? Hyperventilation, may be due to low O2 states Why? Over ingestion of base (antacids), vomiting/NG
Interventions? Slow breathing, rebreather/ paper bag suction losing stomach acid, diuretics increasing H+
or fix oxygenation problem excretion
Breathing? Deep and/or rapid – causing the problem Interventions? Treat underlying cause, Diamox –
Compensation: Metabolicàkidney ↓ HCO3 generic is Acetazolamide (HCO3 waster)
production OR ↑HCO3 removal in urine OR ↓ H+ Compensation: Respiratory- slow & shallow resp.
removal in urine
S/S of Alkalosis: Hypocalcemia (tingling fingers/toes, tetany, Chvostek’s, muscle cramping), ↓K, Nausea/vomiting
