Evaluation of an instrument for noninvasive blood pressure monitoring in the forearm.

Attempts have been made to improve noninvasive clinical blood pressure (BP) monitoring by using monitoring sites more easily accessible than the traditional brachium. The purpose of the current study was to evaluate the performance of an automatic, noninvasive BP monitoring instrument that measures BP at the forearm. The only forearm BP monitoring instrument found on the market was the BP/Clinic (CardioAnalysis Systems). Blood pressure and heart rate (HR) measurements from the BP/Clinic were compared with sequentially recorded BPs determined by the auscultatory method and HRs determined by palpation of the radical artery. Accuracy, precision, and failure rates were determined for the BP/Clinic using linear regression, correlation coefficients, and standard error of the estimates. The accuracy and precision of the BP/Clinic approximated those of the standard methods. Systolic BP (r = 0.82) and HR (r = 0.85) correlated more closely with the standard than did diastolic BP (r = 0.75). It appears from this study that the forearm is an acceptable site for clinically useful systemic BP and HR measurements. In addition, the BP/Clinic performed sufficiently easily, accurately, and reliably to be useful for monitoring BP and HR.