Acid-base

Henderson-Hasselbalch

pH from PaCO₂ and HCO₃ (or HCO₃ from pH and PaCO₂).

acid-base

Required inputs

  • PaCO₂ (mmHg)
  • HCO₃ (mEq/L)

Equation or source

Standard physiology — Henderson 1908, Hasselbalch 1916.

Provenance and release status

Equation / algorithm
pH from PaCO₂ and HCO₃ (or HCO₃ from pH and PaCO₂).
Formula version
hh-v1
Tool version
2.4.0
Clinical risk class
A. EDUCATIONAL CALCULATOR
Release status
Under clinical review
Source status
Direct primary source identifier not yet resolved
Clinical review status
Under clinical verification
Clinical review date
Clinical review date not yet documented

DOI / PMID / direct guideline identifier not yet documented.

Assumptions

  • Entered values and units are accurate and apply to the population described by the cited source.
  • The published equation or rule is being used without a patient-specific clinical adjustment.

Important limitations

  • The result does not replace clinical assessment or establish a diagnosis.
  • Performance outside the source population may differ.
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