An oximeter probe suitable for placement at the nasal alar or nasal septum to measure pulse-based differences in light absorbance across the vascularized tissue of a patient, comprising: a. a first substantially flattened side that is substantially longer than wide, having an inner face and an outer face, and bearing a hinging means of a section of resilient plastic connecting said first side to an opposing second substantially flattened side that is substantially longer than wide; b. said second substantially flattened side, having an inner face and an outer face, said second side connecting to said first side at said hinging means such that the inner faces of both sides substantially oppose each other and, based on the spacing and configuration of the hinging means, are sufficiently separable to widen to encompass said tissue at an operative end; c. at least two light-generating structures that emit light at at least two different wavelength bands known to differentiate oxygenated from non-oxygenated hemoglobin, or a single source generating at least two different light frequencies, positioned at the operative end on the inner face of said first side or said second side; d. at least one light-detecting structure that detects light transmitted from said at least two light-generating structures or said single source, positioned at the operative end on the inner face of the side opposing said at least two light-generating structures or single source; e. first individual conductors for energizing said at least two light-generating structures or single source, connecting said structures to a monitoring system for light signal production and modulation, and second individual conductors connecting said at least one light-detecting structure to said monitoring system to convey signals of light detected by said at least one light-detecting structure, said first and said second individual conductors passing from said probe to said monitoring system; and f. a first sleeve stretched over said first substantially flattened side, and a second sleeve stretched over said second substantially flattened side, wherein each sleeve is one piece, each sleeve is transparent to the critical wavelengths used by the oximeter probe, each sleeve is constructed of a flexible material having a thickness in a range of 0,127-1,27 mm (0.005-0.05 inches), and each sleeve comprises a stretchable aspect of one or more parts, or of the entire sleeve; and wherein (a) said first sleeve encloses said at least two light-generating structures or said single source, and said second sleeve encloses said at least one light-detecting structure, or (b) said first sleeve bears said at least two light-generating structures or said single source, said second sleeve bears said at least one light-detecting structure, or both. a. a first substantially flattened side that is substantially longer than wide, having an inner face and an outer face, and bearing a hinging means of a section of resilient plastic connecting said first side to an opposing second substantially flattened side that is substantially longer than wide; b. said second substantially flattened side, having an inner face and an outer face, said second side connecting to said first side at said hinging means such that the inner faces of both sides substantially oppose each other and, based on the spacing and configuration of the hinging means, are sufficiently separable to widen to encompass said tissue at an operative end; c. at least two light-generating structures that emit light at at least two different wavelength bands known to differentiate oxygenated from non-oxygenated hemoglobin, or a single source generating at least two different light frequencies, positioned at the operative end on the inner face of said first side or said second side; d. at least one light-detecting structure that detects light transmitted from said at least two light-generating structures or said single source, positioned at the operative end on the inner face of the side opposing said at least two light-generating structures or single source; e. first individual conductors for energizing said at least two light-generating structures or single source, connecting said structures to a monitoring system for light signal production and modulation, and second individual conductors connecting said at least one light-detecting structure to said monitoring system to convey signals of light detected by said at least one light-detecting structure, said first and said second individual conductors passing from said probe to said monitoring system; and f. a first sleeve stretched over said first substantially flattened side, and a second sleeve stretched over said second substantially flattened side, wherein each sleeve is one piece, each sleeve is transparent to the critical wavelengths used by the oximeter probe, each sleeve is constructed of a flexible material having a thickness in a range of 0,127-1,27 mm (0.005-0.05 inches), (a) said first sleeve encloses said at least two light-generating structures or said single source, and said second sleeve encloses said at least one light-detecting structure, or (b) said first sleeve bears said at least two light-generating structures or said single source, said second sleeve bears said at least one light-detecting structure, or both.