Patent Document ID: 10092226
Application ID: 13336134
Patent Flag: 1

Claim One:
1. A method for non-invasively measuring hemoglobin concentrations in blood of a subject, the method comprising establishing a pre-determined first relationship between a first variable indicative of total hemoglobin concentration and an intermediate variable, wherein the first relationship is based on blood samples from at least one other subject and the intermediate variable represents a product of absorption coefficient μ a per unit and reduced scattering coefficient μ s ′ per unit volume; determining a second relationship between the intermediate variable and a set of variables that includes second variables indicative of light transmission through tissue and third variables indicative of concentration percentages of different hemoglobin species; storing the first and second relationships in a memory; acquiring in-vivo measurement signals from the subject using a sensor of a pulse oximeter that includes an emitter and a detector performing measurements of at least three wavelengths; determining, based on the in-vivo measurement signals from the subject, in-vivo values for the second and third variables; determining the intermediate variable based on the second relationship; solving for the first variable based on the pre-determined first relationship between the intermediate variable and the first variable; and determining the hemoglobin concentrations based on the first variable and displaying the hemoglobin concentrations on a display unit.