Patent ID: 8738345

Claim:
A method for estimating renal clearance rate of an injected exogenous compound in a patient, the method comprising: inputting a plurality of measured plasma concentration levels from patient samples taken at a plurality of time intervals after bolus injection of an exogenous compound into a computer processor programmed for executing an algorithm for: modeling plasma concentration in the patient samples using a gamma variate (GV) model according to the relationship C ( t )= Kt α−1 e −βt , where K is a concentration scaling function, t is time, α is a shape parameter that is constrained to less than or equal to one, and β is the renal elimination rate constant where lim α -> 1 ⁢ β -> 0 ; using Tikhonov regularization to fit the modeled plasma concentration to temporal data, wherein using Tikhonov regularization includes applying a shrinkage factor λ so that the relative error in plasma clearance s CL within the relationship ( s CL CL ) 2 = s α 2 ⁡ ( a _ 1 + ln ⁢ ⁢ β - Ψ ⁡ ( α ) ) 2 + s β 2 ⁡ ( α β - a _ 2 ) 2 + 2 ⁢ s αβ ⁡ ( a _ 1 + ln ⁢ ⁢ β - Ψ ⁡ ( α ) ) ⁢ ( α β - a _ 2 ) is minimized, where Ψ(α) is the digamma function of α and Ψ(α)=d[lnΓ(α)]/dα=Γ′(α)/Γ(α); generating an output comprising a display of the estimated plasma clearance for the patient.