Peripheral blood circulation state detecting apparatus

A peripheral blood circulation monitor for monitoring peripheral blood circulation of a subject, comprising:

• transmission type blood oxygen saturation measuring means for emitting a first light having a first wavelength and a second light having a second wavelength different from said first wavelength, each toward a body portion of said subject, producing a first photoelectric pulse wave signal indicative of an intensity of the first light transmitted through said body portion of said subject and a second photoelectric pulse wave signal indicative of an intensity of the second light transmitted through said body portion of said subject, and determining a first blood oxygen saturation based on said first and second pulse wave signals;
• reflection type blood oxygen saturation measuring means for emitting a third light having a third wavelength and a fourth light having a fourth wavelength different from aid third wavelength, each toward said body portion of said subject, producing a third photoelectric pulse wave signal indicative of an intensity of the third light reflected from said body portion of said subject and a fourth photoelectric pulse wave signal indicative of an intensity of the fourth light reflected from said body portion of said subject, and determining a second blood oxygen saturation based on said third and fourth pulse wave signals;
• peripheral blood circulation determining means for periodically determining a value representative of a state of peripheral blood circulation of said subject, based on a difference between said first and second blood oxygen saturations, at regular intervals of time;
• and
• informing means for comparing each of the values determined by said peripheral blood circulation determining means, with a predetermined reference value, and informing an operator of the comparison result.