1. An apparatus configured for processing sensor data representative of a body, comprising: an analyzer, comprising: a physical model representative of function of a body constituent, said physical model coded into a digital signal processor embedded in said analyzer, said digital signal processor configured to: generate a prior probability distribution function using said physical model; and repetitively fuse input data originating from at least two types of medical instruments with the prior probability distribution function to generate a posterior probability distribution function, said processor configured to process the posterior probability distribution function to generate an output of at least one of: a monitored parameter value representative of the body; and an estimated parameter value representative of the body.