Length-normalized pulse photoplethysmography: A noninvasive method to measure blood hemoglobin

Thomas K. Aldrich, Mark Moosikasuwan, Samir D. Shah, Kedar S. Deshpande

Research output: Contribution to journalArticlepeer-review

44 Scopus citations


A study was performed to demonstrate that length-normalized pulse photoplethysmography, with measurement of changing attenuation to changing length ratios (D905/l) proximal to the fingernail during arterial pulsations, may be feasible as a noninvasive technique to measure blood hemoglobin. Some 24 subjects were tested, including several with very severe anemia. In these subjects, with normal SpO2, normal metHb and normal to near-normal COHb, using crude instrumentation adapted from off-the-shelf equipment, close correlation was found between [Hb] and D905/l, high sensitivity for the detection of anemia, and an adequate specificity for a screening tool.

Original languageEnglish (US)
Pages (from-to)1291-1298
Number of pages8
JournalAnnals of Biomedical Engineering
Issue number10
StatePublished - 2002


  • Absorption
  • Anemia
  • Clinical monitoring
  • Optical properties
  • Pulse oximetry
  • Sonomicrometry

ASJC Scopus subject areas

  • Biomedical Engineering


Dive into the research topics of 'Length-normalized pulse photoplethysmography: A noninvasive method to measure blood hemoglobin'. Together they form a unique fingerprint.

Cite this