A poor correlation exists between oscillometric and radial arterial blood pressure as measured by the Philips MP90 monitor
- 191 Downloads
In anesthesia and critical care, invasive arterial blood pressure monitoring is the gold standard against which other methods of monitoring are compared. In this assessment of the Philips MP90 monitor, the objective was to determine whether or not oscillometric measurements were within the accuracy standards set by the Association for the Advancement of Medical Instrumentation (AAMI) and the British Hypertension Society (BHS). Three hundred and one invasive and noninvasive paired measurements were obtained from eleven adult patients on the neurosurgical service at Stanford University Medical Center. Bland–Altman plots were created to assess agreement between the two measurement systems. Paired correlation analysis, bias and precision calculations were performed. Oscillometric blood pressure measurements correlated with arterial measurements yielding Pearson r values of 0.68, 0.67 and 0.62 for systolic, diastolic and mean pressures, respectively (P < 0.01.) Mean differences with 95% confidence intervals were −3.8 mmHg ± 13.6, −2.4 mmHg ± 10.0, and 4.0 mmHg ± 13.1 for systolic, diastolic and mean pressures, respectively. The mean difference for these measurements was ≤5 mmHg as stipulated by the AAMI guidelines, but the standard deviation was greater than the 8 mmHg allowed by the AAMI guidelines. When the BHS guidelines were applied, the device merited a grade “D” for systolic and mean arterial pressure, and a grade “C” for diastolic pressure, with the highest possible grade level being “A.” There was a poor correlation between noninvasive and invasive measurements of arterial blood pressure as measured with a cuff and radial arterial cannula using the Philips MP90 monitor. These inaccuracies could lead to unnecessary interventions, or lack of appropriate interventions in anesthetic management. Further study is needed to specify the absolute inaccuracy of the monitor, and to determine if accuracy between the two methods varies with patient co-morbidities, surgical procedures, or anesthetic management.
Keywordsinvasive monitoring blood pressure monitoring anesthesia monitoring blood pressure accuracy
Unable to display preview. Download preview PDF.
- 1.American Society of Anesthesiologists. ASA standards, guidelines and statements; standards for basic anesthesia monitoring: ASA (2005). http://www.asahq.org/publicationsAndServices/sgstoc.htm.
- 8.Association for the Advancement of Medical Instrumentation. American National Standard. Manual, electronic or automated sphygmomanometers ANSI/AAMI SP10-2002/A1. 3330 Washington Boulevard, Suite 400, Arlington, VA 22201-4598, USA: AAMI; 2003.Google Scholar
- 9.O’Brien E, Petrie J, Littler WA, de Swiet M, Padfield PL, Altman D, et al. The British Hypertension Society Protocol for the evaluation of blood pressure measuring devices. J Hypertens. 1993;11(Suppl 2):S43–63.Google Scholar
- 15.Amoore JN, Lemesre Y, Murray IC, Mieke S, King ST, Smith FE, et al. Automatic blood pressure measurement: the oscillometric waveform shape is a potential contributor to differences between oscillometric and auscultatory pressure measurements. J Hypertens. 2008;26(1):35–43.PubMedCrossRefGoogle Scholar
- 16.Amoore JN, Vacher E, Murray IC, Mieke S, King ST, Smith FE, et al. Effect of the shapes of the oscillometric pulse amplitude envelopes and their characteristic ratios on the differences between auscultatory and oscillometric blood pressure measurements. Blood Press Monit. 2007;12(5):297–305.PubMedCrossRefGoogle Scholar
- 17.O’Brien E, Pickering T, Asmar R, Myers M, Parati G, Staessen J, Mengden T, Imai Y, Waeber B, Palatini P with the statistical assistance of Atkins N and Gerin W on behalf of the Working Group on Blood Pressure Monitoring of the European Society of Hypertension. International protocol for validation of blood pressure measuring devices in adults. Blood Press Monit 2002; 7: 3–17.Google Scholar