Accuracy of disposable blood pressure transducers used in the critical care setting.

OBJECTIVES

To assess the initial accuracy, drift in calibration over several hours, and decline in accuracy over daily use of blood pressure transducers used in the critical care setting.

DESIGN

Prospective, criterion standard.

SETTING

Three critical care units in a university hospital.

SUBJECTS

Twenty-seven consecutively available high-pressure transducers were used to measure intra-arterial blood pressures, and 11 consecutively available low-pressure transducers were used to measure central venous and pulmonary arterial blood pressures.

INTERVENTIONS

High-pressure transducers were compared with a mercury column manometer, and low-pressure transducers were compared with a water column manometer at three pressure levels. Data were collected initially after installation of the pressure transducer, at 3 hrs, and at 6 hrs. Data collections were repeated on subsequent days.

MEASUREMENTS AND MAIN RESULTS

a) The majority of pressure transducers are accurate; b) there is no drift in the accuracy of pressure transducers over several hours; c) the accuracy of pressure transducers does not decline over subsequent days. Some transducers over-estimated standard pressures by 10 mm Hg and/or underestimated standard pressure by 17 mm Hg.

CONCLUSIONS

The majority of pressure transducers used in the critical care setting are accurate, although there are some transducers that may compromise patient care. Blood pressure transducers should be checked against a standard manometer upon installation, and daily during use.