A device for insertion into a stomach of a patient for use with enteral feeding, comprising:an indwelling tube (106) having a length；one or more impedance sensors attached along the length of the indwelling tube (106), wherein the one or more impedance sensors are configured to detect a presence or passage of a bolus transitioning through the stomach；a controller (8) in communication with the one or more impedance sensors, wherein the controller (8) is configured to determine measurements of a volume of gastric contents by correlating the presence or passage of the bolus transitioning through the stomach to the volume of gastric contents such that the measurements of the volume of gastric contents provide guidance via the controller for patient care.
