jjangsangy / pulseoximeter

Building a Pulse Oximeter

Building a Pulse Oximeter

Sumission for UCSB Hackathon 2015

Winner of Mindbody API Challenge

Team Members

• Sang Han
• Joshua Wheeler
• Robin Morales
• David Anderson

Introduction

Pulse oximetry is a non-invasive medical diagnostic technique used to measure a persons oxygen saturation.

In medicine, oxygen saturation (SaO2), measures the percentage of hemoglobin binding sites in the bloodstream occupied by oxygen. A puse oximeter relies on the light absorption characteristics of oxygenated/deoxygenated hemoglobin based on an oxygen-hemoglobin dissociation curve represented by the following formula.

Deoxygenated (or reduced) hemoglobin absorbs more red light and allows more infrared light to pass through. Red light is in the 600-750 nm wavelength light band. Infrared light is in the 850-1000 nm wavelength light band.

Photodiode Characteristics

• Absoption: 627-946mm
• Issues: 628nm

Medical significance

Effects of Oxygen Saturation

SaO2	Effect
85% and above	No evidence of impairment
65% and less	Impaired mental function on average
55% and less	Loss of consciousness on average