READ TIME | 7 MINUTES
Exploring the Effect of Movement on the SureBP® Algorithm in a Connex® Spot Monitor
Bruce S. Alpert, David Quinn, Matthew Kinsley, Tyson Whitaker and Thomas T. John.
Key Research Goals
Voluntary and involuntary patient-induced movement can impact the acquisition and accuracy of blood pressure readings. Therefore, researchers designed and implemented a study to determine if the Welch Allyn SureBP algorithm in the Connex Spot Monitor could reliably complete successful and accurate blood pressure readings under these challenging conditions.
Acquiring an accurate blood pressure reading can be challenging for clinicians that work with certain patient populations. For pediatric and geriatric patients, along with those in pain or discomfort, sitting still in the recommended position may not always be feasible. And while testing standards are being developed for transport-induced motion artifacts in blood pressure readings,1 no studies have focused on how to confidently measure blood pressure in these patients.
Researchers developed a study to assess the accuracy of an automated vital signs device—the Welch Allyn Connex Spot Monitor—when it encountered patient-simulated movement that can be common in a clinic or hospital setting. To calculate blood pressure readings, the Connex Spot Monitor utilizes a unique, inflation-based SureBP algorithm.2, 3 Researchers were interested in determining if the Connex Spot Monitor with the SureBP algorithm could still provide precise, consistent and reliable blood pressure readings under those conditions.
Study Parameters: Over the period of two months, 40 participants volunteered to take part in the study. Researchers collected data for readings taken while the patient moved and compared that to measurements taken in stillness. Readings taken with patient-induced motion required study participants to simulate serial pronation and supination of the left arm every five seconds throughout the reading.4 For comparison, manual auscultatory measurements were taken without patient movements before and after the readings where movement was present.
Can’t Stop the Beat: 93% Success Rate in Obtaining a Reading on the First Attempt
The Welch Allyn Connex Spot Monitor with the SureBP algorithm generated a blood pressure value for 93% of patients (37 volunteers) on the first measurement attempt.5 When a second attempt was performed, the device recorded a value in 100% of patients (the remaining three volunteers).6 The automated Welch Allyn device required little to no repeat readings. Beyond reducing the frequency of repeat measurements, this level of successful first-time readings can also help improve the overall patient experience. With fewer measurements to retake, clinicians can instead focus their time on important patient interactions.
Performance Under Pressure: Accuracy in Relation to Movement
In addition to determining the percentage of successful blood pressure readings, researchers also analyzed the accuracy of readings acquired by the automated Welch Allyn device. During this study, the Connex Spot Monitor demonstrated consistency with movement, producing 85-87.5% of readings in a range of +/- 10 mmHg as compared to the manual device for the systolic and diastolic.7,9