Novel tools and techniques are provided for assessing, predicting and/or estimating a probability that a patient is bleeding, in some cases, noninvasively. In various embodiments, tools and techniques are provided for implementing rapid detection of bleeding of the patient or implementing assessment, prediction, or estimation of a probability of bleeding of the patient following injury, in some instances, in real-time before, during, and after fluid resuscitation. According to some embodiments, one or more sensors might monitor physiological data of the patient before, during, and after resuscitation following injury. A computer system might receive and analyze the physiological data, and might estimate a probability that the patient is bleeding, based at least in part on the analyzed physiological data. An indication of at least one of an assessment, prediction, or estimate of a probability that the patient is bleeding may then be displayed on a display device.