The accuracy of rapid oscillometric blood pressure determination

The Dinamap 1846SX (DIN) offers a "stat mode" (SM) for rapid repetitive blood pressure determinations, but its accuracy has not been reported. Thirty patients who required an intra-arterial catheter (IAC) for management of anesthesia underwent induction with concomitant noninvasive blood pressure measurement provided by a DIN set in SM. Computerized automated data acquisition recorded digital outputs from both monitors at the time of new SM readings. Systolic pressure mean absolute error (MAE) was 13.3 +/- 5.7 mmHg (mean +/- SEM) and the mean error (bias) was -8.7 +/- 9.8 mmHg. Mean pressure MAE was 6.8 +/- 3.4 mmHg and bias was -0.5 +/- 6.3 mmHg. Diastolic pressure MAE was 7.0 +/- 3.3 mmHg and bias was -0.3 +/- 6.5 mmHg. There was a tendency for systolic pressure readings to underestimate IAC pressures at higher pressures. These findings echo results reported previously for DIN operating in its normal mode. Rapid arterial pressure determination by SM does not appear to compromise accuracy.