Acid Base Nomogram

Current Readings from Nomogram

 

Normal

H >= 35.50

H <= 44.70

pCO2 >= 37.00

pCO2 <= 44.00

 

Metabolic Acidosis

[a]

H >= -1.98855 * pCO2 + 93.11307

H <= 100

pCO2 >= 9.34

pCO2 <= 18.07

[b]

H >= -1.98855 * pCO2 + 93.11307

H <= -1.90016 * pCO2 + 115.00586

pCO2 > 18.07

pCO2 <= 26.81

[Ac]

H >= 39.8

H <= -1.90016 * pCO2 + 115.00586

pCO2 > 26.81

pCO2 < 37.00

 

Acute Respiratory Acidosis

H >= 0.75036 * pCO2 + 5.94429

H <= 0.77929 * pCO2 + 10.41143

pCO2 > 44.00

pCO2 <= 100.00

 

Chronic Respiratory Acidosis

[a]

H > 0.28482 * pCO2 + 23.66786

H < 0.76645 * pCO2 + 5.17621

pCO2 > 44.00

pCO2 <= 57.83

[b]

H > 0.28482 * pCO2 + 23.66786

H < 0.36827 * pCO2 + 28.20287

pCO2 > 57.83

pCO2 <= 100.00

 

Metabolic Alkalosis

[a]

H >= -0.37272 * pCO2 + 42.93068

H < 35.50

pCO2 >= 37.00

pCO2 <= 44.00

[b]

H >= -0.37272 * pCO2 + 42.93068

H < 0.36516 * pCO2 + 20.13317

pCO2 > 44.00

pCO2 < 48.19

[c]

H >= -0.37272 * pCO2 + 42.93068

H <= -0.25989 * pCO2 + 50.25395

pCO2 >= 48.19

pCO2 < 51.81

[d]

H > 0

H <= -0.25989 * pCO2 + 50.25395

pCO2 >= 51.81

pCO2 <= 62.35

 

Acute Respiratory Alkalosis

H >= 0.77332 * pCO2 + 6.8872

H <= 0.7068 * pCO2 + 13.64852

pCO2 >= 9.00

pCO2 < 37.00

 

Chronic Respiratory Alkalosis

[a]

H > 0.44379 * pCO2 + 20.70493

H < 0.13015 * pCO2 + 34.98438

pCO2 >= 9.00

pCO2 < 26.51

[b]

H > 0.69876 * pCO2 + 13.94585

H < 0.13015 * pCO2 + 34.98438

pCO2 >= 26.51

pCO2 < 37.00

 

Mixed Metabolic and Respiratory Acidosis

[a]

H > -1.90016 * pCO2 + 115.00586

H <= 100

pCO2 > 18.07

pCO2 < 37.00

[b]

H >  44.70

H <=  100

pCO2 >= 37.00

pCO2 <= 44.00

[c]

H > 0.77929 * pCO2 + 10.41143

H <= 100

pCO2 > 44

pCO2 < =100

 

Mixed Acute and Chronic Respiratory Acidosis

H < 0.75036 * pCO2 + 5.94429

H > 0.36827 * pCO2 + 28.20287

pCO2 > 57.83

pCO2 <= 100

 

Mixed Metabolic Alkalosis and Respiratory Acidosis

[a]

H >= -0.25989 * pCO2 + 50.25395

H < 0.28482 * pCO2 + 23.66786

pCO2 > 48.19

pCO2 <= 62.35

[b]

H >= 0

H < 0.28482 * pCO2 + 23.66786

pCO2 > 62.35

pCO2 <= 100

 

Mixed Respiratory and Metabolic Alkalosis

[a]

H >= 0.00

H < 0.77332 * pCO2 + 6.8872

pCO2 >= 9.00

pCO2 < 37.00

[b]

H >= 0.00

H < -0.37272 * pCO2 + 42.93068

pCO2 >= 37.00

pCO2 < 51.81

 

Mixed Acute and Chronic Respiratory Alkalosis

H > 0.7068 * pCO2 + 13.64852

H < 0.4438 * pCO2 + 20.70493

pCO2 >= 9.00

pCO2 < 26.51

 

Mixed Metabolic Acidosis and Respiratory Alkalosis

[a]

H > 0.13015 * pCO2 + 34.98438

H < -1.98855 * pCO2 + 93.11307

pCO2 >= 9.00

pCO2 < 26.81

[b]

H > 0.13015 * pCO2 + 34.98438

H < 39.8

pCO2 >= 26.81

pCO2 < 37.00

 

Previous Readings from Nomogram

 

Coordinates for Normal Range

shape of region: rectangle

 

corners

pH	pCO2
7.35	37 mm Hg
7.45	37
7.35	44
7.45	44

 

Coordinates for Metabolic Acidosis

shape of region: 7-sided shape

 

corners

pH	pCO2
7.00	10.5 mm Hg
7.125	10.5
7.40	28
7.00	18.5
7.095	18.5
7.355	37
7.40	37

 

Coordinates for Chronic Respiratory Alkalosis

shape of region: triangle

 

corners

pH	pCO2
7.445	9.5 mm Hg
7.59	10
7.405	37

 

Coordinates for Acute Respiratory Alkalosis

shape of region: quadrangle

 

corners

pH	pCO2
7.64	9.5
7.8	11.5
7.41	37
7.45	37

 

Coordinates for Metabolic Alkalosis

shape of region: eight sided shape

 

corners

pH	pCO2
7.40	44 Hg
7.47	62
7.72	62 (*)
7.77	52.5 (*)
7.60	52.5
7.53	37
7.45	37
7.45	44

 

(*) line connecting these 2 points runs along the isobar for HCO3 = 75 mEq/L

 

Coordinates for Chronic Respiratory Acidosis

shape of region: quadrangle

 

corners

pH	pCO2
7.36	44 Hg
7.185	100
7.275	100
7.44	44

 

Coordinates for Acute Respiratory Acidosis

shape of region: parallelogram

 

corners

pH	pCO2
7.35	44 mm Hg
7.055	100
7.09	100
7.42	44