There is provided system for monitoring spontaneous breathing of a mechanically ventilated target individual, comprising: a feeding tube for insertion into a distal end of an esophagus of the individual, sensor(s) disposed on the feeding tube at a location such that the sensor(s) is located at the distal end of the esophagus of the individual when the feeding tube is in use, wherein the sensor(s) is positioned for sensing values by contact with the tissue of the esophagus including a lower esophageal sphincter (LES) and/or tissue in proximity to the LES, and code for computing an indication of a frequency band of diaphragm movement of the individual according to an analysis of values sensed by the sensor(s), and for adjustment of parameter(s) of a mechanical ventilator for mechanically ventilating the individual, wherein the instructions for adjustment are computed while the feeding tube is in use.
