ACID-BASE SITUATIONS

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ACID-BASE SITUATIONS

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Title: ACID-BASE SITUATIONS

1
ACID-BASE SITUATIONS
2
Objectives

After todays presentation you will
List the primary causes of respiratory acidosis
List the primary causes of respiratory alkalosis
Given a set of electrolytes, determine the anion
gap
List the primary causes of a metabolic acidosis
with an increased anion gap
List the primary causes of a metabolic acidosis
with a normal anion gap
List the primary causes of a metabolic alkalosis

3
ACID-BASE DISTURBANCES
4
Respiratory Disturbances
5
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6
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7
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8
Metabolic Disturbances
9
Metabolic Acidosis
10
General Causes of Metabolic Acidosis

Failure of kidneys to excrete metabolic acids
normally found in the body.
Formation of excess quantities of metabolic acids
in the body.
Addition of metabolic acids to the body by
ingestion or infusion of acids.
Loss of base from the body fluids.

11
Anion Gap

Two ways to evaluate
Na - Cl- - HCO3-
Normal is 6 to 12 mEq/L
Na K - Cl- - HCO3-
Normal is 10 to 16

12
Anion Gap

http//www.thedrugmonitor.com/acidbase.html

13
Increased Anion Gap

Greater than 20 Accumulation of Fixed Acids
NORMAL CHLORIDE LEVEL
MUD PILERS
Methanol
Uremia (Azotemic Renal Failure)
Elevated BUN/Creatinine
Diabetic Ketoacidosis
Paraldehyde (Formaldehyde and Toluene)
Isopropyl alcohol
Lactic (and Formic) Acidosis
Ethylene Glycol
Rhabdomyolysis
Salicylates

14
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15
Normal Anion Gap

INCREASED CHLORIDE LEVEL LOSS OF BASE
Renal Tubular Acidosis
No reabsorption of HCO3-
Enteric Drainage Tubes
Small intestine drainage Large amounts of base
in stool
Diarrhea
Urinary Diversion
Surgical alteration of ureters
Carbonic Anhydrase Inhibitors
Poor reabsorption of bicarbonate

16
Low Anion Gap

Look at albumin
Hypoalbuminemia causes a low anion gap.
Normal Albumin is 4.4 g/dL
For every 0.4 g/dL decrease in albumin, the anion
gap will decrease by 1 mEq/L

Albumin (g/dL) Maximum Anion Gap (mEq/L)
4.4 16
4.0 15
3.6 14
3.2 13
2.8 12
17
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18
Example of Extreme Compensation

On 2 L/min NC
pH 6.96
PaCO2 6.8 mm Hg
PaO2 158 mm Hg
HCO3- 1.5 mEq/L
BE -32.6 mEq/L

19
Metabolic Alkalosis

Most common acid-base abnormality?
Aggressive treatment of partially compensated
respiratory acidosis?
Causes
Loss of Acid
Vomiting
NG Drainage
Gain of Alkali
Increased ingestion of alkaline substances
Excessive licorice ingestion
Hypokalemia

20
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21
Advance Acid Base Interpretation
22
Classification vs. Interpretation

Classification Identification of acid-base
disturbance and the causative element along with
any compensation that may be present.
Interpretation Use of calculations to determine
if compensation is appropriate or if multiple
disorders are present.

23
Compensation

There is no such thing as overcompensation.
This usually means there is a second primary
disorder at work in the opposite direction.
If there is no compensation OR the compensation
is less than expected
Compensation is not possible because the
compensatory organ is not functioning
appropriately.
There has not been sufficient time for
compensation (renal).
Another primary disorder is present and is
working in the same direction.

24
PaCO2 pH HCO3-
RESPIRATORY ACIDOSIS RESPIRATORY ACIDOSIS RESPIRATORY ACIDOSIS RESPIRATORY ACIDOSIS
Acute ?10 ? 0.08 ? 1 mEq/L
Chronic ?10 ? 0.03 ? 4 mEq/L
RESPIRATORY ALKALOSIS RESPIRATORY ALKALOSIS RESPIRATORY ALKALOSIS RESPIRATORY ALKALOSIS
Acute ?10 ? 0.08 ? 2 mEq/L
Chronic ?10 ? 0.03 ? 5 mEq/L
HCO3- pH PaCO2
METABOLIC ACIDOSIS ? 1 ? 0.015 ? 1.2
METABOLIC ALKALOSIS ?1 ?0.015 ? 0.7
25
Degree of Variation

Allow for some degree of variation as follows
pH 0.03
PaCO2 5 mm Hg

26
Oakes Approach

Primary Problem (Acidemia or Alkalemia)
Primary Cause
CO2
HCO3-
Compensation
Initial Classification (Technical and Functional)
Determine extent of compensation and the presence
of other abnormalities
Determine Anion Gap for metabolic acidemia
Determine Oxygenation
Assess Patient
Check for Accuracy
Final Interpretation

27
Factors That May Complicate Acid-Base
Determination

Chronic Lung Disease
Chronic Renal Disease
Therapeutic interventions
Mixed Acid-Base Problems

28
COPD

Typical picture is fully compensated, respiratory
acidosis.
pH 7.38
PaCO2 55 mm Hg
HCO3- 31 mEq/L
BE 5 mEq/L
PaO2 55 mm Hg
Lets go through the process.

29
7.38, 55, 31

Acidosis
CO2 is elevated, so there is a respiratory
cause.
HCO3- is out of normal range, but is not the
cause.
The body is compensating.
Technical Classification Fully compensated
respiratory acidosis.
Functional Classification Chronic respiratory
acidosis.

30
7.38, 55, 31

Change in CO2 15 torr
Change in pH -0.02
Change in HCO3- 7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40
PaCO2 40 torr 55
HCO3- 24 mEq/L
31
7.38, 55, 31
For every 10 torr change in PaCO2 there is a
0.03 change in pH. pH D (1.5 x
.03)0.045 7.40-0.0457.36

Change in CO2 15 torr
Change in pH -0.02
Change in HCO3- 7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40
PaCO2 40 torr 55
HCO3- 24 mEq/L
32
7.38, 55, 31
For every 10 torr change in PaCO2 there is a
0.03 change in pH. pH D (1.5 x
.03)0.045 7.40-0.0457.36

Change in CO2 15 torr
Change in pH -0.02
Change in HCO3- 7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.36
PaCO2 40 torr 55
HCO3- 24 mEq/L
33
7.38, 55, 31
For every 10 torr change in PaCO2 there is a 4
mEq/L change in HCO3-. HCO3- D (1.5 x
4)6 24630 mEq/L

Change in CO2 15 torr
Change in pH -0.02
Change in HCO3- 7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.36
PaCO2 40 torr 55
HCO3- 24 mEq/L
34
7.38, 55, 31
For every 10 torr change in PaCO2 there is a 4
mEq/L change in HCO3-. HCO3- D (1.5 x
4)6 24630 mEq/L

Change in CO2 15 torr
Change in pH -0.02
Change in HCO3- 7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.36
PaCO2 40 torr 55
HCO3- 24 mEq/L 30
35
7.38, 55, 31
Actual HCO3- (31) doesnt match the predicted
change in HCO3-, so there must be an underlying
metabolic alkalosis superimposed on the
compensation.

Change in CO2 15 torr
Change in pH -0.02
Change in HCO3- 7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.36
PaCO2 40 torr 55
HCO3- 24 mEq/L 30 31
36
7.38, 55, 31
For every 1 mEq/L change in HCO3- there is a
0.015 change in pH. pH D (1 x .015)
0.150.2 7.36 0.2 7.38

Change in CO2 15 torr
Change in pH -0.02
Change in HCO3- 7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.36
PaCO2 40 torr 55
HCO3- 24 mEq/L 30 31
37
7.38, 55, 31
For every 1 mEq/L change in HCO3- there is a
0.015 change in pH. pH D (1 x .015)
0.150.2 7.36 0.2 7.38

Change in CO2 15 torr
Change in pH -0.02
Change in HCO3- 7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.36 7.38
PaCO2 40 torr 55
HCO3- 24 mEq/L 30 31
38
7.38, 55, 31

Change in CO2 15 torr
Change in pH -0.02
Change in HCO3- 7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.36 7.38
PaCO2 40 torr 55
HCO3- 24 mEq/L 30 31
39
COPD

So our final interpretation is a fully
compensated, respiratory acidosis with a
secondary metabolic alkalemia.
pH 7.38
PaCO2 55 mm Hg
HCO3- 31 mEq/L
BE 5 mEq/L
PaO2 55 mm Hg
This may be due to hypochloremia and hypokalemia
associated with steroids and diuretics.

40
COPD Relative Hyperventilation

If the patient below develops a hypoxemic episode
(e.g. pneumonia), the resulting hypoxemia may
cause the patient to hyperventilate, the PaCO2 to
return to normal, and a metabolic alkalosis to
be diagnosed.
This is often seen when first starting the
patient on BiPAP or mechanical ventilation

pH 7.38 PaCO2 55 mm Hg HCO3- 31 mEq/L BE 5
mEq/L PaO2 55 mm Hg
pH 7.52 PaCO2 40 mm Hg HCO3- 31 mEq/L BE 5
mEq/L PaO2 50 mm Hg
Solution is to only correct the PaCO2 to 52 mm Hg
41
COPD with Lactic Acidosis

COPD Reduced Cardiac Output Cellular hypoxia
and Lactic Acidosis
Dont be fooled by normal ABGs

pH 7.38 PaCO2 40 mm Hg HCO3- 24 mEq/L BE 1
mEq/L PaO2 44 mm Hg
pH 7.38 PaCO2 55 mm Hg HCO3- 31 mEq/L BE 5
mEq/L PaO2 55 mm Hg
Loss of HCO3- due to lactic acidosis.
42
Chronic Renal Failure

Chronic renal failure can distort ABG results.
Renal ability to manipulate HCO3-, electrolyte
and fluid levels is impaired.
Always evaluate with a metabolic acidosis as a
possible cause.

43
Therapeutic Interventions

Multiple therapeutic interventions can affect
acid-base balance
Diuretics
Steroids
Electrolytes
Oxygen
Sodium Bicarbonate
Mechanical Ventilation

44
Lets try another

Interpret this ABG
pH 7.44
PaCO2 18 mm Hg
BE -12 mEq/L
HCO3- 12 mEq/L
PaO2 64 mm Hg

45
7.44, 18, 12

Normal, but on alkalotic side.
CO2 is reduced, so there is a respiratory cause.
HCO3- is out of normal range, but is not the
cause as a lowered HCO3- would not cause an
alkalosis.
The body is compensating.
Technical Classification Fully compensated
respiratory alkalosis.
Functional Classification Chronic respiratory
alkalosis.

46
7.44, 18, 12

Change in CO2 -22 torr
Change in pH 0.04
Change in HCO3- -12 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40
PaCO2 40 torr 18
HCO3- 24 mEq/L
47
7.44, 18, 12
For every 10 torr change in PaCO2 there is a
0.03 change in pH. pH D (2.2 x
.03)0.066 7.400.0667.47

Change in CO2 -22 torr
Change in pH 0.04
Change in HCO3- -12 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40
PaCO2 40 torr 18
HCO3- 24 mEq/L
48
7.44, 18, 12
For every 10 torr change in PaCO2 there is a
0.03 change in pH. pH D (2.2 x
.03)0.066 7.400.0667.47

Change in CO2 -22 torr
Change in pH 0.04
Change in HCO3- -12 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.47
PaCO2 40 torr 18
HCO3- 24 mEq/L
49
7.44, 18, 12
For every 10 torr change in PaCO2 there is a 5
mEq/L change in HCO3-. HCO3- D (2.2 x
5)11 24-1113 mEq/L

Change in CO2 -22 torr
Change in pH 0.04
Change in HCO3- -12 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.47
PaCO2 40 torr 18
HCO3- 24 mEq/L
50
7.44, 18, 12
For every 10 torr change in PaCO2 there is a 5
mEq/L change in HCO3-. HCO3- D (2.2 x
5)11 24-1113 mEq/L

Change in CO2 -22 torr
Change in pH0.04
Change in HCO3- -12 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.47
PaCO2 40 torr 18
HCO3- 24 mEq/L 13
51
7.44, 18, 12
Actual HCO3- (12) doesnt match the predicted
change in HCO3-, so there must be an underlying
metabolic acidosis superimposed on the
compensation.

Change in CO2 -22 torr
Change in pH 0.04
Change in HCO3- -12 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.47
PaCO2 40 torr 18
HCO3- 24 mEq/L 13 12
52
7.44, 18, 12
For every 1 mEq/L change in HCO3- there is a
0.015 change in pH. pH D (1 x .015)
0.150.2 7.47 - 0.2 7.45

Change in CO2 -22 torr
Change in pH 0.04
Change in HCO3- -12 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.47
PaCO2 40 torr 18
HCO3- 24 mEq/L 13 12
53
7.44, 18, 12
For every 1 mEq/L change in HCO3- there is a
0.015 change in pH. pH D (1 x .015)
0.150.2 7.47 - 0.2 7.45

Change in CO2 -22 torr
Change in pH 0.04
Change in HCO3- -12 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.47 7.45
PaCO2 40 torr 18
HCO3- 24 mEq/L 13 12
54
7.44, 18, 12
The predicted pH of 7.45 is within the degree of
variation of 0.03 for pH.

Change in CO2 -22 torr
Change in pH 0.04
Change in HCO3- -12 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.47 7.45
PaCO2 40 torr 18
HCO3- 24 mEq/L 13 12
55
Interpretation

Fully compensated respiratory alkalosis with
simultaneous metabolic acidosis.

56
Mixed Acid-Base Disturbances

Sometimes a simple compensatory mechanism isnt
the reason for the normalized acid-base status.
If two opposing problems co-exist (ARF causing
metabolic acidosis and pain causing respiratory
alkalosis), you may have what looks like one
compensating for the other.

Interpret this ABG
pH 7.38
PaCO2 20 mm Hg
HCO3- 17 mEq/L
PaO2 89 mm Hg

58
7.38, 20, 17

Normal, but on acidotic side.
CO2 is reduced, which would not cause an
alkalosis.
HCO3- is reduced and would cause an alkalosis.
The body is compensating.
Technical Classification Fully compensated
metabolic acidosis.
Functional Classification Metabolic acidosis.

59
7.38, 20, 17
For every 1 mEq/L change in HCO3- there is a
0.015 change in pH. pH D (7 x
.015)0.105 7.40-0..1057.30

Change in CO2 -20 torr
Change in pH -0.02
Change in HCO3- -7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40
PaCO2 40 torr
HCO3- 24 mEq/L 17
60
7.38, 20, 17
For every 1 mEq/L change in HCO3- there is a
0.015 change in pH. pH D (7 x
.015)0.105 7.40-0.1057.30

Change in CO2 -20 torr
Change in pH -0.02
Change in HCO3- -7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.30
PaCO2 40 torr
HCO3- 24 mEq/L 17
61
7.38, 20, 17
The calculated change in pH (7.30) differs from
the actual measured pH, so there must be some
additional acid-base disturbance.

Change in CO2 -20 torr
Change in pH -0.02
Change in HCO3- -7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.30
PaCO2 40 torr
HCO3- 24 mEq/L 17
62
7.38, 20, 17
For every 1 mEq/L change in HCO3- there is a 1.2
change in PaCO2. PaCO2 D (7 x
1.2)8.4 40-8.431.632

Change in CO2 -20 torr
Change in pH -0.02
Change in HCO3- -7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.30
PaCO2 40 torr
HCO3- 24 mEq/L 17
63
7.38, 20, 17
The calculated change in PaCO2 (32) differs from
the actual measured PaCO2, so there must be a
respiratory disturbance present.

Change in CO2 -20 torr
Change in pH -0.02
Change in HCO3- -7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.30
PaCO2 40 torr 32
HCO3- 24 mEq/L 17
64
7.38, 20, 17
The difference between the calculated change in
PaCO2 (32) and the actual PaCO2 (20), indicates
that there must be a respiratory disturbance
present.

Change in CO2 -20 torr
Change in pH -0.02
Change in HCO3- -7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.30
PaCO2 40 torr 31.6 20
HCO3- 24 mEq/L 17
65
7.38, 20, 17
For every 10 torr change in PaCO2 there is a 0.08
change in pH. pH D (1.2 x .08)0.096 7.30.0967
.396

Change in CO2 -20 torr
Change in pH -0.02
Change in HCO3- -7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.30
PaCO2 40 torr 31.6 20
HCO3- 24 mEq/L 17
66
7.38, 20, 17
The predicted pH is within the level of
variability of 0.03 units.

Change in CO2 -20 torr
Change in pH -0.02
Change in HCO3- -7 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.30 7.40
PaCO2 40 torr 31.6 20
HCO3- 24 mEq/L 17
67
Interpretation

Mixed metabolic acidosis and simultaneous
respiratory alkalosis.

68
Can you have a triple disorder?
69
Anion Bicarbonate Gaps

Anion Gap Na - Cl- - HCO3-
Normal value is 6 to 12
Above 20 considered High
Bicarbonate Gap HCO3- (AG-12)
Normal is 20 to 28 AG Metabolic Acidosis
Less than 20 AG Metabolic Acidosis Non-AG
Metabolic Acidosis
Greater than 28 AG Metabolic Acidosis
Metabolic Alkalosis

70
7.52, 30, 21

Alkalemia.
CO2 is reduced, which would cause an alkalosis.
Primary respiratory alkalosis.
HCO3- is reduced and would not cause an
alkalosis.
The body is compensating (HCO3- decreasing)
Technical Classification Partially compensated
respiratory alkalosis.
Functional Classification Chronic respiratory
alkalosis.

71
7.52, 30, 21
For every 10 torr change in PaCO2 there is a 0.03
change in pH. pH D (1 x .03)0.03 7.40.037.43

Change in CO2 -10 torr
Change in pH 0.12
Change in HCO3- -3 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40
PaCO2 40 torr 30
HCO3- 24 mEq/L
72
7.52, 30, 21
For every 10 torr change in PaCO2 there is a 0.03
change in pH. pH D (1 x .03)0.03 7.40.037.43

Change in CO2 -10 torr
Change in pH 0.12
Change in HCO3- -3 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.43
PaCO2 40 torr 30
HCO3- 24 mEq/L
73
7.52, 30, 21
The calculated change in pH (7.43) differs from
the actual measured pH, so there must be some
additional acid-base disturbance.

Change in CO2 -10 torr
Change in pH 0.12
Change in HCO3- -3 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.43
PaCO2 40 torr 30
HCO3- 24 mEq/L
74
7.52, 30, 21
For every 10 torr change in PaCO2 there is a 5
mEq/L change in HCO3-. HCO3- D (1 x
5)5 24-519 mEq/L

Change in CO2 -10 torr
Change in pH 0.12
Change in HCO3- -3 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.43
PaCO2 40 torr 30
HCO3- 24 mEq/L
75
7.52, 30, 21
For every 10 torr change in PaCO2 there is a 5
mEq/L change in HCO3-. HCO3- D (1 x
5)5 24-519 mEq/L

Change in CO2 -10 torr
Change in pH 0.12
Change in HCO3- -3 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.43
PaCO2 40 torr 30
HCO3- 24 mEq/L 19
76
7.52, 30, 21
The calculated change in HCO3-differs from the
actual measured HCO3-, so there must be some
additional acid-base disturbance.

Change in CO2 -10 torr
Change in pH 0.12
Change in HCO3- -3 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.43
PaCO2 40 torr 30
HCO3- 24 mEq/L 19 21
77
7.52, 30, 21
For every 1 mEq/L change in HCO3- there is a
0.015 change in pH. pH D (2 x
.015)0.03 7.430.037.46

Change in CO2 -10 torr
Change in pH 0.12
Change in HCO3- -3 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.43
PaCO2 40 torr 30
HCO3- 24 mEq/L 19 21
78
7.52, 30, 21
For every 1 mEq/L change in HCO3- there is a
0.015 change in pH. pH D (2 x
.015)0.03 7.430.037.46

Change in CO2 -10 torr
Change in pH 0.12
Change in HCO3- -3 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.43 7.46
PaCO2 40 torr 30
HCO3- 24 mEq/L 19 21
79
7.52, 30, 21
Note that the pH still is not fully explained by
the change in bicarbonate due to compensation.
Some additional metabolic alkalosis must be
present.

Change in CO2 -10 torr
Change in pH 0.12
Change in HCO3- -3 mEq/L

BASELINE Disorder 1 Disorder 1 Disorder 2 Disorder 2
pH 7.40 7.43 7.46
PaCO2 40 torr 30
HCO3- 24 mEq/L 19 21
80
Look to Anion Bicarbonate Gaps

Na 142 mEq/L
Cl- 98 mEq/L
AG Na - Cl- - HCO3- 142-98-21 23
This means we have an Anion Gap Metabolic
Acidosis
BG HCO3- (AG-12) 21 (23-12) 2111 32
AG Metabolic Acidosis Metabolic Alkalosis

81
Interpretation

Primary respiratory alkalosis and metabolic
acidosis and metabolic alkalosis.
Huh?
An example would be a patient with pneumonia who
is hyperventilating secondary to hypoxemia, who
also has azotemic renal failure and has
hypokalemia secondary to aggressive diuretic
therapy.

82
7.52, 30, 21