Abstract: A method for detection of interference in impedance based monitoring of a subject by using a monitor is disclosed. The method comprising, connecting the subject to the monitor using one or more leads; and before current is applied to the subject, measuring voltage on the subject via at least one of the one or more leads and if any voltage is detected then the monitor indicates a warning. An impedance based monitor is disclosed, the monitor being connectable to a subject. The monitor is configured to measure voltage on the subject, before any current is applied to the subject, and if any voltage is detected then the monitor is configured to indicate a warning.

Abstract: A method for detection of interference in impedance based monitoring of a subject by using a monitor is disclosed. The method comprising, connecting the subject to the monitor using one or more leads; and before current is applied to the subject, measuring voltage on the subject via at least one of the one or more leads and if any voltage is detected then the monitor indicates a warning. An impedance based monitor is disclosed, the monitor being connectable to a subject. The monitor is configured to measure voltage on the subject, before any current is applied to the subject, and if any voltage is detected then the monitor is configured to indicate a warning.

Abstract: A method for giving a measurement of quality for impedance based respiration monitoring is disclosed. The method comprises attaching a lead to a subject, the lead being connected to a monitor, and receiving a signal from the lead, the lead being used for impedance respiration monitoring; estimating amplitude of cardiovascular artifact, CVA, derived from the signal of the lead; estimating amplitude of respiration derived from the signal of the lead; calculating a quality factor for the lead based on the estimated amplitude of CVA and the estimated amplitude of respiration; and indicating the quality factor for the lead to the user via the monitor.