Equipment & Physics — Monitors, Humidification, Suction, Ventilators and Safety

Also known as Equipment and physics · Humidification · Endotracheal suctioning · Transport ventilator · Electrical safety · Pulse oximetry · Capnography · Defibrillator · Pressure transducer

ICU equipment by failure mode: pulse-oximetry bias (including skin pigmentation), capnography and its limits, arterial-line dynamic response and line-cuff discrepancy, temperature sites, humidification targets and HME versus heated humidifier outcomes, endotracheal suctioning, transport ventilators, oxygen supply failure, electrical safety, CO2 absorbents and biphasic defibrillation.

high26 referencesUpdated 8 Oct 202610 min readSource-verified · Oct 2026

Checked against its sources on 8 Oct 2026

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Why equipment physics matters in the ICU

Every number on an ICU monitor is the output of a device with known failure modes. Pulse oximetry has a documented list of sources of inaccuracy; intra-arterial pressure accuracy depends on the dynamic response of the measuring system; capnography carries limitations as a surrogate for PaCO2; and humidifiers, suction systems, transport ventilators and the oxygen supply each fail in predictable ways.^[1]^[7]^[5]^[21] This topic is organised device by device: what the device measures or delivers, how it errs, and what the evidence says about choosing between options.

References26Show

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