Device, apparatus and method for obtaining physiological signals by way of a feeding tube

An esophageal feeding tube including:

• a molded or jacketed build-up of discrete parts such as lumen, wires, or electromechanical components;
• wire layered onto a center lumen that is over-molded, cast, or encapsulated after layering;
• molded in-wall wires in a single lumen or a multi-lumen extrusion;
• or
• a discrete wire bundle installed into one of multiple lumens, the multiple lumens physically separate a feeding path in one of the lumens from the electromechanical components;
• a tubular construction defining at least one lumen that provides a pathway for nourishment from outside of a subject into a stomach or small intestine of the subject surrounded by a jacket;
• at least one of:
• fiber-optic filaments that provide light to a fiber optic window adjacent to the jacket that senses pulse and SpO2;
• a soft molded tip that is attached to a distal end of the feeding tube;
• a light source at the tip of the feeding tube for visually tracking the tip of the feeding tube;
• or
• a distal electrode at the tip of the feeding tube for indicating when the tip of the feeding tube passes into the stomach of the subject;
• at least two electrodes that are uniformly or non-uniformly spaced, on the outside of the tube for measuring cardiac activity of the subject, of which at least one electrode is used at any given time;
• and
• a monitor which implements a monitoring algorithm to select which of the electrodes has an optimal signal, such that the algorithm can be implemented when the feeding tube is inserted or periodically as the subject grows and the feeding tube is repositioned.

A method of measuring a respiration flow rate, the method comprising:

• inserting an orogastric or nasogastric feeding tube that defines at least one lumen that provides a pathway for nourishment into an esophagus of a subject;
• advancing the feeding tube to a position estimated to place a tip of the feeding tube in a selected location in a stomach or small intestine of the subject to position an oropharynx thermistor in a region of a pharynx of the subject and a hypopharynx thermistor inferior to the pharynx of the subject;
• sensing a temperature in the region of the subject's pharynx with the oropharynx thermistor:
• sensing a temperature inferior to the subject's pharynx with the hypopharynx thermistor,
• determining the respiration flow rate from a relative temperature change between the oropharynx thermistor and the hypopharynx thermistor.