abstract |
The invention comprises methods for noninvasively monitoring physiological characteristics of a patient's blood. Determinations of blood constituent concentrations may be made by comparing absorbance of radiation at varying parameters, such as path length and blood pressure. In one embodiment, the changes in the height of the probes relative to the patient's heart effect the changes in pressure. This particular method uses a digital level sensor (114), a heat level sensor (116), and a probe that has emitters (98, 100) and a detector (106). The digital level sensor (114) and the heart level sensor (116) are connected to an amplifier (118) and a converter (109). The output from the converter (109) is processed and the results are sent to display (112). In other embodiments, the temperature of the blood may also be accurately determined as well as cardiac output characteristics, blood pressures, and blood pH. |