A medical apparatus for reducing the risk of electric shock to a medical patient, the apparatus comprising: a plurality of physiological sensors (150; 250a, 250b; 850; 1050), at least one of the physiological sensors comprising: a light emitter configured to impinge light on body tissue of a living patient, the body tissue including pulsating blood, and a detector responsive to the light after attenuation by the body tissue, wherein the detector is configured to generate a signal indicative of a physiological characteristic of the living patient; and a splitter cable (220b; 620) operative to connect the plurality of physiological sensors (150; 250a, 250b; 850; 1050) to a port on a physiological monitor (110; 210; 810; 1010), the splitter cable (220b; 620) comprising: a monitor connector (221; 621) that can connect to the physiological monitor (110; 210; 810; 1010); a plurality of sensor connectors (223, 631) that can each connect to one of the physiological sensors (150; 250a, 250b; 850; 1050); a plurality of cable sections (222; 622, 630a, 630b), each disposed between a sensor connector of the plurality of sensor connectors and the monitor connector (221; 621), each cable section (222; 622, 630a, 630b) comprising one or more electrical conductors configured to interface with one of the physiological sensors (150; 250a, 250b; 850; 1050); characterized by one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) disposed in the splitter cable (220b; 620), the one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) being in communication with selected ones of the one or more electrical conductors, the one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) configured to communicate physiological signals between one or more of the physiological sensors (150; 250a, 250b; 850; 1050) and the physiological monitor (110; 210; 810; 1010), the one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) operative to electrically decouple the physiological sensors (150; 250a, 250b; 850; 1050) from each other. a plurality of physiological sensors (150; 250a, 250b; 850; 1050), at least one of the physiological sensors comprising: a light emitter configured to impinge light on body tissue of a living patient, the body tissue including pulsating blood, and a detector responsive to the light after attenuation by the body tissue, wherein the detector is configured to generate a signal indicative of a physiological characteristic of the living patient; and a light emitter configured to impinge light on body tissue of a living patient, the body tissue including pulsating blood, and a detector responsive to the light after attenuation by the body tissue, wherein the detector is configured to generate a signal indicative of a physiological characteristic of the living patient; and a splitter cable (220b; 620) operative to connect the plurality of physiological sensors (150; 250a, 250b; 850; 1050) to a port on a physiological monitor (110; 210; 810; 1010), the splitter cable (220b; 620) comprising: a monitor connector (221; 621) that can connect to the physiological monitor (110; 210; 810; 1010); a plurality of sensor connectors (223, 631) that can each connect to one of the physiological sensors (150; 250a, 250b; 850; 1050); a plurality of cable sections (222; 622, 630a, 630b), each disposed between a sensor connector of the plurality of sensor connectors and the monitor connector (221; 621), each cable section (222; 622, 630a, 630b) comprising one or more electrical conductors configured to interface with one of the physiological sensors (150; 250a, 250b; 850; 1050); characterized by one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) disposed in the splitter cable (220b; 620), the one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) being in communication with selected ones of the one or more electrical conductors, the one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) configured to communicate physiological signals between one or more of the physiological sensors (150; 250a, 250b; 850; 1050) and the physiological monitor (110; 210; 810; 1010), the one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) operative to electrically decouple the physiological sensors (150; 250a, 250b; 850; 1050) from each other. a monitor connector (221; 621) that can connect to the physiological monitor (110; 210; 810; 1010); a plurality of sensor connectors (223, 631) that can each connect to one of the physiological sensors (150; 250a, 250b; 850; 1050); a plurality of cable sections (222; 622, 630a, 630b), each disposed between a sensor connector of the plurality of sensor connectors and the monitor connector (221; 621), each cable section (222; 622, 630a, 630b) comprising one or more electrical conductors configured to interface with one of the physiological sensors (150; 250a, 250b; 850; 1050); characterized by one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) disposed in the splitter cable (220b; 620), the one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) being in communication with selected ones of the one or more electrical conductors, the one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) configured to communicate physiological signals between one or more of the physiological sensors (150; 250a, 250b; 850; 1050) and the physiological monitor (110; 210; 810; 1010), the one or more decoupling circuits (240b; 540a; 540b; 540c; 540d) operative to electrically decouple the physiological sensors (150; 250a, 250b; 850; 1050) from each other.