User Related Errors
Sensing and Information Processing
Failure to perceive alarms – A study conducted by Eslamian 2010 found that nurses had a 28.3% probability of failing to perceive alarms due to distractions or ignoring signals due to frequent false positives. In order to avoid this, the device alarm and delivery settings were optimized to only alert the nurse under very specific conditions. While this should drop the chance of missing alarms, there is no data on what the exact probability is for error [1].
Misread/misinterpret the screen – Eslamian 2010 also found that 29% of nurses are prone to misreading the screen, which could result in missing irregular readings pertaining to patient oxygen uptake and sudden drops in respiratory rate. Fortunately, this is not as much of an issue since alarms will alert the nurse if any irregularities in patient conditions arise [1].
Control Capabilities
Users input wrong alarm settings – Eslamian [1] found that 28.3% of nurses surveyed intentionally raise the alarm threshold or completely disable alarms on medical devices in an effort to avoid irritation of an alarm going off with frequent false positives. In addition to the alarm on this device not being able to be turned off, there is a range at which the alarm threshold must be set in order for the device to be operational. This not only eliminates malicious users but user error as well, dropping the error potential to 0%.
Users input wrong O2 delivery settings – This is primarily due to user error, 28% of nurses surveyed by Eslamian 2010 [1] admitted to occasionally inputting incorrect settings into medical devices for patients. Once again, we have implemented threshold limits for O2 delivery settings to make the device inoperable unless a safe value is selected. The worst case scenario is a slightly elevated oxygen delivery rate, which may cause some minor discomfort to the patient. The potential for dangerous O2 delivery settings to be selected is near 0%.
References:
[1] J Eslamian, F Taheri, S Mojdeh, "Assessing the Nursing Error Rate and Related Factors from the View of Nursing Staff," Iran J Nurs Midwifery Res, 15(Suppl1): 272–277, 2010.