Evaluating the performance of automated sphygmomanometers using a patient simulator

Area of Science:

• Biomedical Engineering
• Medical Devices
• Cardiovascular Technology

Background:

• Automated sphygmomanometers utilize the oscillometric method, relying on algorithms that link oscillometric pulse amplitude to cuff pressure.
• Current validation relies on manufacturer-specific clinical trials, leading to non-harmonized algorithms based on diverse arterial waveforms.
• This variability necessitates standardized testing to ensure accurate and consistent blood pressure measurements.

Purpose of the Study:

• To evaluate the performance of six automated sphygmomanometers using a patient simulator.
• To assess the impact of non-harmonized algorithms on blood pressure measurement accuracy.
• To identify the need for standardization in validation protocols for automated blood pressure devices.

Main Methods:

• Six automated sphygmomanometers (upper arm and wrist-based) were tested using a patient simulator.
• Simulations covered four distinct blood pressure levels (80/50, 120/80, 150/100, 200/150 mmHg).
• Devices underwent conformity assessment, and measurement repeatability variance was analyzed.

Main Results:

• All devices met metrological requirements (within ±2 mmHg for static calibration).
• Significant discrepancies (>20 mmHg) were found between upper arm and wrist-based models.
• Upper arm devices showed diastolic pressure differences up to 12.8 mmHg.

Conclusions:

• Observed discrepancies have potential clinical implications, underscoring the need for standardized algorithms and harmonized validation.
• Wrist-based device algorithms may be compromised by using brachial artery waveforms for validation.
• Current validation approaches, especially with patient simulators, require standardization.