Version 2.77


Base excess refers to the amount of a strong acid required to bring back the blood pH to the normal value of 7.4. The term and concept were first introduced by Astrup and Siggaard-Andersen in 1958 as a way to measure the metabolic component of an acid-base disturbance.

Actual versus standard:
In vivo, acid-base homeostasis takes place throughout the extracellular fluid (ECF), not just the blood compartment that is in a patient specimen. The concept of "standard" base excess attempts to adjust for the base excess of the entire extracellular compartment by calculating the base excess for blood diluted as if the entire extracellular compartment were sampled (approx Hgb of 5g/l). So the ACTUAL base excess (ABE) is the dose of acid to return PLASMA to normal pH, whereas the STANDARD base excess (SBE) is the dose to return ECF to normal pH.

Adjusting for oxygen saturation:
Base excess normally assumes 100% oxygen saturation, which is valid for many arterial specimens. However, it is possible to add additional terms to the calculation which account for the actual oxygen saturation of the patient sample. The terms in LOINC indicating 'Base excess.100% oxygenated' are intended to encode base excess terms adjusted for oxygen saturation (i.e. do not assume 100% oxygenation). Source: Regenstrief LOINC

Basic Part Properties

Part Display Name
Base excess
Part Type
Component (Describes the core component or analyte measured)
Created On
Construct for LOINC Short Name
Base excess

LOINC Terminology Service (API) using HL7® FHIR® Get Info

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Language Variants Get Info

Tag Language Translation
zh-CN Chinese (China) 碱剩余
Synonyms: BE;BSE;碱超;碱过剩;过剩碱
fr-CA French (Canada) Excès de base
et-EE Estonian (Estonia) Aluste liig
es-ES Spanish (Spain) Exceso de base
it-IT Italian (Italy) Basi, eccesso
Synonyms: Eccesso di basi
tr-TR Turkish (Turkey) Baz fazlalığı
ru-RU Russian (Russian Federation) Оснований избыток
nl-NL Dutch (Netherlands) base-overschot
fr-BE French (Belgium) Excès de base