ICU SAQs · Equipment & physics
The pulse oximetry — the principle and the limitations
A CICM First-Part SAQ on pulse oximetry — the red 660 nm and the infrared 940 nm, the differential absorption, the pulse-added isolation, and the limitations (the pigmentation, the CO, the low perfusion, the motion).
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CICMFFICMEDIC
Prompt
Explain the physical principle of the pulse oximetry and describe the factors that cause the inaccurate reading.
Question
Explain the physical principle of the pulse oximetry and describe the factors that cause the inaccurate reading.
[2]References3ShowHide
- [1]Moon K, et al. Pulse oximetry - a perioperative perspective. Diagnostics (Basel), 2026.PMID 42351472
- [2]León-Valladares D, Barrio-Mateu LA, Cortés-Carmona N, et al. Determining factors of pulse oximetry accuracy: a literature review. Revista Clinica Espanola, 2024.PMID 38599519
- [3]Cotton SA, et al. Do differences in skin pigmentation affect detection of hypoxemia by pulse oximetry: a systematic review. Clinical Nursing Research, 2025.PMID 41045137