The effects of pulse rate, artefact and pulse strength on oscillometric non-invasive blood pressure measurements.

We examined the effects of pulse rate, pulse and artefact on 20 adult oscillometric non-invasive blood pressure measurements using NIBP test simulators. Over a range of pulse rates from 40 to 200 bpm the 20 NIBP monitors studied recorded little change in registered pressures. The monitors achieved consistent readings at low pulse rates by decreasing the deflation rate and hence increasing the determination time (from under 20 sec at 200 bpm to over 30 sec at 40 bpm). High levels of artefact produced artificially high systolic pressures in 12 of the 16 monitors that recorded pressures, 6 of them being over 30 mmHg above the target 120 mmHg; 4 of the monitors signalled failure to record due to excessive artefact. Pulse strengths of 25% of the nominal were coped with well by most monitors with a slight tendency for the monitors to record low systolic pressures.