Legibility of a volumetric infusion pump in a shock trauma ICU.
Reports submitted to the Federal Food and Drug Administration (FDA) indicate that legibility of infusion pump interfaces contributes to medication errors (for example, patients have been seriously injured when nurses overinfused them after reading the number 7 as a 1). Health care has experienced an influx of medical devices with small-screen interfaces, generically described as small-screen devices. Legibility is widely acknowledged as a necessary aspect of safe operation of medical devices. Contextual analysis was used to observe conditions affecting the legibility of the screen interface of a dual-channel infusion volumetric infusion pump in a shock trauma intensive care unit (STICU). Observations were made of registered nurses and physicians using the infusion pumps during a four-hour period. Results from the observations indicated that there was reduced legibility of the infusion pump screen interface because of an inherently subdued light situation, reduced screen contrast, and the small font size of the lettering. It was clear from the beginning of the observations that the screen of the infusion pump had limited legibility. In some instances, nurses attached handmade tape labels to the infusion pump to enhance and supplement the small screen. The pump was often positioned facing away from the nurses, who then had to reposition it to view the screen, contributing to interruptions in work flow and creating a potential safety hazard. A variety of strategies are recommended to ensure legibility of infusion pump interfaces and of medical-device labels. A more complete environmental approach is needed to determine the legibility and usefulness of microdisplay and small-screen devices in health care.