A ventilation monitoring device, comprising: at least two electrodes configured to measure a transthoracic impedance of the subject; optionally, at least one capnography sensor configured to detect a partial pressure of carbon dioxide in a subject's breathing gases; at least one processor; and at least one memory (225, 230) including computer program code, the at least one memory and the computer program code configured with the at least one processor to cause the ventilation monitoring device to determine whether an intubated subject's tracheal tube is properly placed, characterized in that the determining is done by: initiating a timer for measuring a predetermined time limit, receiving an indication of a subject's breath from the at least two electrodes (135a, 135b) configured with the ventilation monitoring device to measure a transthoracic impedance of the subject, or optionally from the at least one capnography sensor, receiving an indication of a positive result of a first auscultation, receiving an indication of a positive result of a second auscultation for an area of the subject's body different from an area of the body of the first auscultation, receiving an indication of a positive result of a third auscultation for an area of the subject's body different from area of the first auscultation and the second auscultation, and determining that the subject's tracheal tube is properly placed when the indication of the subject's breath and the indication of the positive result of the first auscultation, the second auscultation, and the third auscultation are received within the predetermined time limit measured by the timer. at least two electrodes configured to measure a transthoracic impedance of the subject; optionally, at least one capnography sensor configured to detect a partial pressure of carbon dioxide in a subject's breathing gases; at least one processor; and at least one memory (225, 230) including computer program code, the at least one memory and the computer program code configured with the at least one processor to cause the ventilation monitoring device to determine whether an intubated subject's tracheal tube is properly placed, characterized in that the determining is done by: initiating a timer for measuring a predetermined time limit, receiving an indication of a subject's breath from the at least two electrodes (135a, 135b) configured with the ventilation monitoring device to measure a transthoracic impedance of the subject, or optionally from the at least one capnography sensor, receiving an indication of a positive result of a first auscultation, receiving an indication of a positive result of a second auscultation for an area of the subject's body different from an area of the body of the first auscultation, receiving an indication of a positive result of a third auscultation for an area of the subject's body different from area of the first auscultation and the second auscultation, and determining that the subject's tracheal tube is properly placed when the indication of the subject's breath and the indication of the positive result of the first auscultation, the second auscultation, and the third auscultation are received within the predetermined time limit measured by the timer. initiating a timer for measuring a predetermined time limit, receiving an indication of a subject's breath from the at least two electrodes (135a, 135b) configured with the ventilation monitoring device to measure a transthoracic impedance of the subject, or optionally from the at least one capnography sensor, receiving an indication of a positive result of a first auscultation, receiving an indication of a positive result of a second auscultation for an area of the subject's body different from an area of the body of the first auscultation, receiving an indication of a positive result of a third auscultation for an area of the subject's body different from area of the first auscultation and the second auscultation, and determining that the subject's tracheal tube is properly placed when the indication of the subject's breath and the indication of the positive result of the first auscultation, the second auscultation, and the third auscultation are received within the predetermined time limit measured by the timer.