EBMcalc Medical Calculator

Henderson-Hasselbach Equation

Input

HCO3

PaCO2

Result

Important: Inputs must be complete to perform calculation.

Decimal Precision

Data action

Include literature references: Yes No

Equations used

pH = 6.1 + log(HCO3 / (0.03 * PaCO2))

References

Bleich HL. Computer Evaluation of Acid-Base Disorders. J Clin Invest. 1969; 48:1689-1696. PubMed ID: 4898409

Associated Medical Subject Headings [MeSH]

Acid-Base Equilibrium, Acidosis, Alkalosis, Computer-Assisted, Computers, Data Display, Diagnosis, Humans

Associated Logical Observation Identifiers Names and Codes [LOINC]

Parameter	LOINC's and Suggested Units
HCO3	2028-9 : mmol/L 1959-6 : mEq/L 1960-4 : mEq/L 14627-4 : mEq/L 1961-2 : mEq/L 22735-5 : mEq/L 1963-8 : mEq/L
PaCO2	2019-8 : mmHg 34705-4 : mmHg
pH	11558-4 : units 2753-2 : units 2744-1 : units 2745-8 : units 2746-6 : units

This material contains content from LOINC (http://loinc.org). LOINC is copyright © 1995-2023, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and is available at no cost under the license at http://loinc.org/license. LOINC® is a registered United States trademark of Regenstrief Institute, Inc.

Associated ICD10-CM codes

E87.3

Alkalosis

E87.2

Acidosis

Associated ICD9-CM codes

276.2

Acidosis

276.3

Alkalosis

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