Assessment of the Hewlett-Packard HP47210A capnometer

The Hewlett-Packard HP47210A Capnometer, a "mainstream" infra-red carbon dioxide analyser, has a sensor in-line with the patient circuit. The calibration apparatus is included within the unit, and an internal microprocessor corrects for the presence of nitrous oxide and varying concentrations of oxygen. Maximum error was 0.37 kPa for carbon dioxide partial pressures less than 5.3 kPa, and less than 3.6% for partial pressures of carbon dioxide greater than 5.3 kPa.