Validierung der kontinuierlichennicht-invasiven Blutdruckmessung mittels Puls-Transit-Zeit

BACKGROUND AND OBJECTIVE: Arterial bloodpressure measured by pulse transit time (PTT) can be used as analternative to the gold standard of invasive measurement. It wasthe aim of this study to compare these two methods in order to validatePTT in patients with cardiac diseases. PATIENTS AND METHODS: In 40 patients(29 males; mean age 68.7 ± 15 years)in a cardiac intensive care unit, blood pressures were continuouslymeasured by PTT and the standardized invasive method for one hour.Values were analysed and compared in 30-second intervals (9,600values for each method). RESULTS: Blood pressures obtained witheither method were not statistically different, neither in the wholegroup nor in subgroups. However, the number of analysable data wassignificantly higher using the invasive method, by which appropriate signalswere obtained in 99.2 % of systolic and in 99.1 % ofdiastolic blood pressure measurements. In contrast, using the PTT-method,appropriate signals were seen in 85.8 % of systolicand 85.9 % of diastolic pressure measurements. CONCLUSION: Blood pressures measuredby PTT in patients in cardiac intensive care units provide reliablevalues over a period of at least one hour. However, the PTT methodseems to be more susceptible to errors as evidenced by the numberof failed measurements.