Lapis ISSN 2398-2969

Hematology: hemoglobin concentration

Synonym(s): Hb

Contributor(s): Michael Waters, Molly Varga, Vetstream Ltd

Overview

  • The amount of hemoglobin (Hb) in a stated volume is a measure of the oxygen-carrying ability of blood.
  • Use is equivalent to packed cell volume (PCV)   Hematology: packed cell volume  .

Sampling

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Tests

Methodologies

Cyanomethemoglobin
  • Ferricyanide converts hemoglobin iron from the ferrous to the ferric state to form methemoglobin which combines with potassium cyanide to form the stable pigment cyanomethemoglobin.
  • Error 1-2% in automated systems and 2-5% in manual methods.
  • Measures all forms of Hb likely to be in blood.

Oxyhemoglobin

  • Uses Spencer Hb meter to measure oxyhemoglobin by its light absorption in the green portion of the spectrum using a filter and matching the color with a colored glass standard.
  • Practical, quick and accurate (+/- 5-10%).

Does not measure methemoglobin and carboxyhemoglobin.

Other methods

  • Acid hematin and direct matching are outmoded and unsatisfactory.

Availability

  • Widely available at commercial laboratories.

Validity

Sensitivity

  • Good.

Specificity

  • High.

Predictive value

  • Good.

Technique (intrinsic) limitations

  • These techniques do not differentiate between different types of Hb.

Technician (extrinsic) limitations

  • Results needs to be repeatable.
  • Technical skill required.

Result Data

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Further Reading

Publications

Refereed papers

  • Recent references fromPubMed.

Other sources of information

  • Campbell T W & Ellis C K (2007)Avian and Exotic Hematology and Cytology.3rd edn. Wiley-Blackwell. ISBN: 978-0813818115.
  • Latimer K S, Mahaffey E A & Prasse K W (2003)Duncan and Presse's Veterinary Laboratory Medicine.4th edn. Wiley-Blackwell. ISBN: 978-0813820705.
  • Feldman B F, Zinkl J G & Jain N C (2000)Schalm's Veterinary Hematology.5th edn. Lippincott, Williams & Wilkins, Baltimore, USA.


ADDED