Validation of inflationary noninvasive blood pressure monitoring in the emergency room

OBJECTIVE: The aim of this study was to compare the values of a noninvasive blood pressure (NIBP) measurement during cuff inflation (inflationary NIBP) and deflationary NIBP measurements and to verify whether inflationary NIBP is equivalent to conventional deflationary NIBP and is acceptable for clinical use in the emergency room (ER). MATERIALS AND METHODS: A total of 2981 NIBP data points were collected from 175 patients (age, 56.5±22.2 years; range, 7–92 years) who had been treated in the resuscitation area of the ER at Keio University Hospital. The data points were obtained using two alternate algorithms with a standard monitor (BSM-6000). One algorithm consisted of continuous inflationary and deflationary measurements in a single cycle (dual algorithm, 1502 data points); this algorithm was used to verify the success rate and the precision of the data. The second algorithm (1479 data points) consisted of only conventional deflationary measurements and was used to verify the duration of the measurement cycle. RESULTS: The success rate of the inflationary NIBP (completed using only the inflationary method) was 69.0%. Failures in the inflationary measurements were caused by arrhythmia and/or body motions. The mean difference and SD of the systolic pressure and the diastolic pressure between inflationary NIBP and deflationary NIBP were −0.6±8.8 and 3.5±7.5 mmHg, respectively. The confidence intervals were −0.6 (95% confidence interval=−1.1 to −0.1) and 3.5 (95% confidence interval=3.0 to 4.0) mmHg. The coefficients of correlation were 0.96 and 0.93. Inflationary NIBP was capable of determining the NIBP more quickly compared with deflationary NIBP (average of 15.9 vs. 34.2 s; P<0.05). CONCLUSION: Inflationary NIBP measurements have a reasonable accuracy and a sufficient rapidity, compared with deflationary NIBP measurements, in ER patients.