Wound fluid blood detection systems and methods are described that are operable in conjunction with reduced pressure wound treatment (RPWT) systems, as well as ancillary therapy and monitoring systems applied concurrently with RPWT systems. The blood detection monitor operates by optically characterizing the content of wound fluids to the extent of identifying percentage blood content. This identification relies upon the transmission of select wavelengths of light across a volume of wound fluid to a photo detector (connected to signal processing instrumentation) capable of quantifying the absorption characteristics of the fluid. The detection components may be implemented in conjunction with either a fluid flow conduit (i.e. the reduced pressure tubing directing fluid away from the wound dressing) or more directly in association with the materials that comprise the wound dressing positioned within the wound bed itself. In addition, the present invention is configured to operate in conjunction with blood gas monitoring systems operating with the RPWT. Finally, the components of the systems that serve to illuminate the wound bed, lend themselves to use in conjunction with illumination in discreet electromagnetic wave wavelengths suitable for the application of phototherapy.