Statistical considerations for testing automated sphygmomanometers in special patient populations.

The International Standards Organization 81060-2:2018 is the current global Standard for the validation of automated sphygmomanometers. It specifies the requirements for clinical studies on the general population, as well as additional requirements for special populations, which might have physiologic characteristics that affect the accuracy of blood pressure measurements. This paper summarizes the statistical methodology behind the sample size required to test automated sphygmomanometers in these special populations and specifically addresses the pregnant patient population.

Industry perspectives on the global use of validated blood pressure measuring devices.

A group of experts from reputable blood pressure measuring device (BPMD) manufacturers was invited to provide industry perspectives on the global use of validated BPMD. The authors support the recommendations of (1) using the consolidated universal ISO 81060-2:2018 in all future validation studies to ensure consistent and trustworthy quality standards; (2) validation studies to be led by investigators independent from the manufacturer; (3) validation study results to be published in peer-reviewed journals with an independent investigator as the corresponding author; and (4) validated BPMDs to be listed on validated device registries such as STRIDE BP, Validated Device Listing (VDL), and others that are backed by acknowledged scientific associations. The authors call for public awareness of the existence of legally marketed consumer BPMDs that lack sufficient evidence of clinical accuracy. Other important issues and future considerations were discussed, including the need: for awareness building and promoting the use of validated BPMDs among practitioners; to identify a non-mercury sphygmomanometer based reference device to validate BPMDs; to include all cuffs available for use with each BPMD in the validation study; for the promotion of validation studies for special patient populations; for validated wrist BPMDs as an alternative for some patients; for technical innovations to help reduce limitations related to the human aspect of validation studies; for validation of cuffless BPMDs; for validation through equivalency to validated base models; and to use validated BPMD in remote patient monitoring programs. A future collaborative to find solutions to support the use of validated BPMD is envisaged.

Evaluating the impact of motion artifact on noninvasive blood pressure devices.

Most automated sphygmomanometers use oscillometric algorithms. Motion, either patient-based or environmental, will affect the ability of a device to record an accurate blood pressure (BP). Members of the Association for the Advancement of Medical Instrumentation (AAMI) Sphygmomanometer Committee have been studying this problem for more than a decade. The AAMI TIR44 was the first publication to address the challenges of motion tolerance. The concepts described in TIR44 have led to the development of a draft of ISO 81060-4, a new standard for testing devices for which the manufacturer wishes to claim motion tolerance. The current ISO 81060-2 addresses both stress testing and 24-hour ambulatory BP monitoring. Recent publications have reported on testing of devices in response to voluntary and involuntary patient motion. The ISO 81060-4 will address testing in the presence of patient transport by ground, fixed-wing, and rotary (helicopter) ambulances. The protocol will utilize noise profiles recorded under those three conditions. The profiles will be digitally stored on a library with free access. The proposed testing will be performed using patient simulators introducing the noise library files into known BP oscillometric envelopes. The specifications of the data capture and playback devices are specified, as is the evaluation statistical testing. The authors expect that the final draft will be published in 2020.