According to some embodiments, a system for detecting a perfusion index of a cardiac pulse includes a first sensor that senses a first physiological or environmental parameter of a human patient core, a second sensor that senses a second physiological or environmental parameter of the human patient core, a processor that, responsive to the first and second sensed parameters, determines a perfusion index ranging from 0 to 10 that reflects inadequate, marginal, or adequate blood perfusion to the core of the human patient torso, and an indicator that provides a discernible indication of the perfusion index. A method of detecting as perfusion index of a cardiac pulse responsive to sensing first and second physiological or environmental parameters of a human patient core is also disclosed.