Table 2 Pulse oximetry specifications for hospital operating theatres
Environmental issues and other specificationsOximeters should comply with relevant standards such as International Electrotechnical Commission (IEC) 69691-1 and International Standards Organisation (ISO)9919:2005. Units should work reliably in a wide range of operating temperatures (e.g. 10°C to 40°C) and humidities (e.g. relative humidity 15–95%).
Physical featuresUnits should be robust enough to withstand falls of 1 m onto concrete. Portability and ease of handling is desirable.
Power supplyUnits must be able to be powered by rechargeable batteries, normal batteries and mains supply electricity.
Ease of useOximeters should be intuitive and simple to use. Interfaces should be language free to the extent possible, although it may be suitable to have configurable language displays.
AlarmsAlarms indicating breaches of safe limits of oxygen saturation should be audible and supplemented with a visible change of display (such as flashing). Ideally an alarm should indicate sensor misplacement.
Oxygen saturationArterial oxygen saturation should be measured between clinically relevant limits (e.g. 70–100%) with reasonable accuracy (e.g. ±2% of true saturation).
Pulse displayThe device should have a plethysmograph display of the pulse (either waveform or bar graph). The unit should measure pulse rate between clinically appropriate limits (e.g. 20–200 beats·min−1) to ±3 beats·min−1. The pulse rate should also be displayed numerically and be represented by an audible tone, which changes as saturation levels deteriorate.
DisplayThe readout should be clearly visible from 5 m.
Sensors/probesProbes should be as robust as possible. A range of sensors covering various sizes and ages of patient should be available, and all probes should be reusable.
Warranties and maintenanceThe expected life of the oximeter and probes should be specified and appropriate warranties provided. User and service manuals should be provided, electronically and by hard copy, in a variety of languages.