Biomedical instrumentation & technology / Association for the Advancement of Medical Instrumentation
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Biomed Instrum Technol · May 1993
A new sodium-nitroprusside-infusion controller for the regulation of arterial blood pressure.
Automatic optimization of the infusion rate of sodium nitroprusside (SNP) is achieved by an integrated hardware-software closed-loop controller implemented as a small bedside device. A microprocessor-based blood pressure monitor controls an infusion pump. The shape of the arterial pressure wave is digitally sampled; its analysis incorporates artifact-detection and -rejection routines. ⋯ The first 240 minutes of the postoperative period were closely watched, taking into account 1) the percentage of time during which MAP was within the 10-mmHg wide frame above the target pressure (target gap); 2) the mean difference of pressure values that crossed the boundary of the target gap; 3) the mean SNP-infusion rate. With automatic control, the time mean arterial pressure values were located in the target gap during the first hour amounted to 72.8 +/- 6.7%, vs 51.2 +/- 10.3% in the manual-control group. In the second hour, it was 79.3 +/- 2.5% vs 67.4 +/- 11.7% (p < 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)