Evaluations of Physiological Monitoring Displays: A Systematic Review

Staff perspectives on the influence of patient characteristics on alarm management in the intensive care unit: a cross-sectional survey study

BACKGROUND

High rates of clinical alarms in the intensive care unit can result in alarm fatigue among staff. Individualization of alarm thresholds is regarded as one measure to reduce non-actionable alarms. The aim of this study was to investigate staff's perceptions of alarm threshold individualization according to patient characteristics and disease status.

METHODS

This is a cross-sectional survey study (February-July 2020). Intensive care nurses and physicians were sampled by convenience. Data was collected using an online questionnaire.

RESULTS

Staff view the individualization of alarm thresholds in the monitoring of vital signs as important. The extent to which alarm thresholds are adapted from the normal range varies depending on the vital sign monitored, the reason for clinical deterioration, and the professional group asked. Vital signs used for hemodynamic monitoring (heart rate and blood pressure) were most subject to alarm individualizations. Staff are ambivalent regarding the integration of novel technological features into alarm management.

CONCLUSIONS

All relevant stakeholders, including clinicians, hospital management, and industry, must collaborate to establish a "standard for individualization," moving away from ad hoc alarm management to an intelligent, data-driven alarm management. Making alarms meaningful and trustworthy again has the potential to mitigate alarm fatigue - a major cause of stress in clinical staff and considerable hazard to patient safety.

TRIAL REGISTRATION

The study was registered at ClinicalTrials.gov (NCT03514173) on 02/05/2018.

Requirements for a Bespoke Intensive Care Unit Dashboard in Response to the COVID-19 Pandemic: Semistructured Interview Study

BACKGROUND

Intensive care units (ICUs) around the world are in high demand due to patients with COVID-19 requiring hospitalization. As researchers at the University of Bristol, we were approached to develop a bespoke data visualization dashboard to assist two local ICUs during the pandemic that will centralize disparate data sources in the ICU to help reduce the cognitive load on busy ICU staff in the ever-evolving pandemic.

OBJECTIVE

The aim of this study was to conduct interviews with ICU staff in University Hospitals Bristol and Weston National Health Service Foundation Trust to elicit requirements for a bespoke dashboard to monitor the high volume of patients, particularly during the COVID-19 pandemic.

METHODS

We conducted six semistructured interviews with clinical staff to obtain an overview of their requirements for the dashboard and to ensure its ultimate suitability for end users. Interview questions aimed to understand the job roles undertaken in the ICU, potential uses of the dashboard, specific issues associated with managing COVID-19 patients, key data of interest, and any concerns about the introduction of a dashboard into the ICU.

RESULTS

From our interviews, we found the following design requirements: (1) a flexible dashboard, where the functionality can be updated quickly and effectively to respond to emerging information about the management of this new disease; (2) a mobile dashboard, which allows staff to move around on wards with a dashboard, thus potentially replacing paper forms to enable detailed and consistent data entry; (3) a customizable and intuitive dashboard, where individual users would be able to customize the appearance of the dashboard to suit their role; (4) real-time data and trend analysis via informative data visualizations that help busy ICU staff to understand a patient's clinical trajectory; and (5) the ability to manage tasks and staff, tracking both staff and patient movements, handovers, and task monitoring to ensure the highest quality of care.

CONCLUSIONS

The findings of this study confirm that digital solutions for ICU use would potentially reduce the cognitive load of ICU staff and reduce clinical errors at a time of notably high demand of intensive health care.

Defining information needs in neonatal resuscitation with work domain analysis

OBJECTIVE

To gain a deeper understanding of the information requirements of clinicians conducting neonatal resuscitation in the first 10 min after birth.

BACKGROUND

During the resuscitation of a newborn infant in the first minutes after birth, clinicians must monitor crucial physiological adjustments that are relatively unobservable, unpredictable, and highly variable. Clinicians' access to information regarding the physiological status of the infant is also crucial to determining which interventions are most appropriate. To design displays to support clinicians during newborn resuscitation, we must first carefully consider the information requirements.

METHODS

We conducted a work domain analysis (WDA) for the neonatal transition in the first 10 min after birth. We split the work domain into two 'subdomains'; the physiology of the neonatal transition, and the clinical resources supporting the neonatal transition. A WDA can reveal information requirements that are not yet supported by resources.

RESULTS

The physiological WDA acted as a conceptual tool to model the exact processes and functions that clinicians must monitor and potentially support during the neonatal transition. Importantly, the clinical resources WDA revealed several capabilities and limitations of the physical objects in the work domain-ultimately revealing which physiological functions currently have no existing sensor to provide clinicians with information regarding their status.

CONCLUSION

We propose two potential approaches to improving the clinician's information environment: (1) developing new sensors for the information we lack, and (2) employing principles of ecological interface design to present currently available information to the clinician in a more effective way.

Avatar-based versus conventional vital sign display in a central monitor for monitoring multiple patients: a multicenter computer-based laboratory study

BACKGROUND

Maintaining adequate situation awareness is crucial for patient safety. Previous studies found that the use of avatar-based monitoring (Visual Patient Technology) improved the perception of vital signs compared to conventional monitoring showing numerical and waveform data; and was further associated with a reduction of perceived workload. In this study, we aimed to evaluate the effectiveness of Visual Patient Technology on perceptive performance and perceived workload when monitoring multiple patients at the same time, such as in central station monitors in intensive care units or operating rooms.

METHODS

A prospective, within-subject, computer-based laboratory study was performed in two tertiary care hospitals in Switzerland in 2018. Thirty-eight physician and nurse anesthetists volunteered for the study. The participants were shown four different central monitor scenarios in sequence, where each scenario displayed two critical and four healthy patients simultaneously for 10 or 30 s. After each scenario, participants had to recall the vital signs of the critical patients. Perceived workload was assessed with the National Aeronautics and Space Administration Task-Load-Index (NASA TLX) questionnaire.

RESULTS

In the 10-s scenarios, the median number of remembered vital signs significantly improved from 7 to 11 using avatar-based versus conventional monitoring with a mean of differences of 4 vital signs, 95% confidence interval (CI) 2 to 6, p < 0.001. At the same time, the median NASA TLX scores were significantly lower for avatar-based monitoring (67 vs. 77) with a mean of differences of 6 points, 95% CI 0.5 to 11, p = 0.034. In the 30-s scenarios, vital sign perception and workload did not differ significantly.

CONCLUSIONS

In central monitor multiple patient monitoring, we found a significant improvement of vital sign perception and reduction of perceived workload using Visual Patient Technology, compared to conventional monitoring. The technology enabled improved assessment of patient status and may, thereby, help to increase situation awareness and enhance patient safety.

Critical care information display approaches and design frameworks: A systematic review and meta-analysis

OBJECTIVE

To systematically review original user evaluations of patient information displays relevant to critical care and understand the impact of design frameworks and information presentation approaches on decision-making, efficiency, workload, and preferences of clinicians.

METHODS

We included studies that evaluated information displays designed to support real-time care decisions in critical care or anesthesiology using simulated tasks. We searched PubMed and IEEExplore from 1/1/1990 to 6/30/2018. The search strategy was developed iteratively with calibration against known references. Inclusion screening was completed independently by two authors. Extraction of display features, design processes, and evaluation method was completed by one and verified by a second author.

RESULTS

Fifty-six manuscripts evaluating 32 critical care and 22 anesthesia displays were included. Primary outcome metrics included clinician accuracy and efficiency in recognizing, diagnosing, and treating problems. Implementing user-centered design (UCD) processes, especially iterative evaluation and redesign, resulted in positive impact in outcomes such as accuracy and efficiency. Innovative display approaches that led to improved human-system performance in critical care included: (1) improving the integration and organization of information, (2) improving the representation of trend information, and (3) implementing graphical approaches to make relationships between data visible.

CONCLUSION

Our review affirms the value of key principles of UCD. Improved information presentation can facilitate faster information interpretation and more accurate diagnoses and treatment. Improvements to information organization and support for rapid interpretation of time-based relationships between related quantitative data is warranted. Designers and developers are encouraged to involve users in formal iterative design and evaluation activities in the design of electronic health records (EHRs), clinical informatics applications, and clinical devices.

Association of Data Integration Technologies With Intensive Care Clinician Performance: A Systematic Review and Meta-analysis

IMPORTANCE

Sources of data in the intensive care setting are increasing exponentially, but the benefits of displaying multiparametric, high-frequency data are unknown. Decision making may not benefit from this technology if clinicians remain cognitively overburdened by poorly designed data integration and visualization technologies (DIVTs).

OBJECTIVE

To systematically review and summarize the published evidence on the association of user-centered DIVTs with intensive care clinician performance.

DATA SOURCES

MEDLINE, Embase, Cochrane Central Register of Controlled Trials, PsycINFO, and Web of Science were searched in May 2014 and January 2018.

STUDY SELECTION

Studies had 3 requirements: (1) the study tested a viable DIVT, (2) participants involved were intensive care clinicians, and (3) the study reported quantitative results associated with decision making in an intensive care setting.

DATA EXTRACTION AND SYNTHESIS

Of 252 records screened, 20 studies, published from 2004 to 2016, were included. The human factors framework to assess health technologies was applied to measure study completeness, and the Quality Assessment Instrument was used to assess the quality of the studies. PRISMA guidelines were adapted to conduct the systematic review and meta-analysis.

MAIN OUTCOMES AND MEASURES

Study completeness and quality; clinician performance; physical, mental, and temporal demand; effort; frustration; time to decision; and decision accuracy.

RESULTS

Of the 20 included studies, 16 were experimental studies with 410 intensive care clinician participants and 4 were survey-based studies with 1511 respondents. Scores for study completeness ranged from 27 to 43, with a maximum score of 47, and scores for study quality ranged from 46 to 79, with a maximum score of 90. Of 20 studies, DIVTs were evaluated in clinical settings in 2 studies (10%); time to decision was measured in 14 studies (70%); and decision accuracy was measured in 11 studies (55%). Measures of cognitive workload pooled in the meta-analysis suggested that any DIVT was an improvement over paper-based data in terms of self-reported performance, mental and temporal demand, and effort. With a maximum score of 22, median (IQR) mental demand scores for electronic display were 10 (7-13), tabular display scores were 8 (6.0-11.5), and novel visualization scores were 8 (6-12), compared with 17 (14-19) for paper. The median (IQR) temporal demand scores were also lower for all electronic visualizations compared with paper, with scores of 8 (6-11) for electronic display, 7 (6-11) for tabular and bar displays, 7 (5-11) for novel visualizations, and 16 (14.3-19.0) for paper. The median (IQR) performance scores improved for all electronic visualizations compared with paper (lower score indicates better self-reported performance), with scores of 6 (3-11) for electronic displays, 6 (4-11) for tabular and bar displays, 6 (4-11) for novel visualizations, and 14 (11-16) for paper. Frustration and physical demand domains of cognitive workload did not change, and differences between electronic displays were not significant.

CONCLUSIONS AND RELEVANCE

This review suggests that DIVTs are associated with increased integration and consistency of data. Much work remains to identify which visualizations effectively reduce cognitive workload to enhance decision making based on intensive care data. Standardizing human factors testing by developing a repository of open access benchmarked test protocols, using a set of outcome measures, scenarios, and data sets, may accelerate the design and selection of the most appropriate DIVT.

A Usability Study of 3 Radiotherapy Systems: A Comparative Evaluation Based on Expert Evaluation and User Experience

BACKGROUND The complex user interface design of radiotherapy treatment delivery systems can lead to use error and patient harm. In this study, we present the results of a comparison of 3 radiotherapy treatment delivery systems now used in China. MATERIAL AND METHODS We conducted a comprehensive usability study of 3 radiotherapy treatment delivery systems. Expert evaluation was performed through heuristic evaluation with 3 human-factors experts and 1 experienced radiation therapist for each system. User experience was assessed through perceived system usability and workload, using the National Aeronautics and Space Administration Task Load Index and the Post-Study System Usability Questionnaire. RESULTS For the expert evaluation, 47 usability problems were identified for Varian Trilogy, 75 for Elekta Precise, and 37 for Shinva XHA600E. Most problems were classified as major and minor usability problems, and were found in the process of patient setup and setup verification. For the user experience, radiation therapists presented a lower workload for Varian Trilogy compared to Elekta Precise (P<0.01) and Shinva XHA600E (P<0.01), and a lower workload for Elekta Precise compared to Shinva XHA600E (P=0.020). Radiation therapists perceived a higher system usability for Varian Trilogy compared to Shinva XHA600E (P<0.01), and a higher system usability for Elekta Precise compared to Shinva XHA600E (P<0.01). CONCLUSIONS This research provides valuable data on how 3 radiotherapy treatment delivery systems compare. The results of this study may be useful for hospital equipment procurement decisions, and designing next-generation products to improve patient safety.

Comprehensive Evaluation of User Interface for Ventilators Based on Respiratory Therapists' Performance, Workload, and User Experience

Background

Poor ergonomic design of ventilators can result in human errors. In this study, we evaluated the ergonomics of ventilators through respiratory therapists’ performance, workload, and user experience.

Material/Methods

Sixteen respiratory therapists were recruited to this usability study of 3 ventilators. Participants had to perform 7 tasks on each ventilator. Respiratory therapists’ performance was measured by task errors of all tasks for each participant. Workload was measured by objective measurement (blink rate and duration) and by subjective measurement (NASA-TLX). User experience was assessed by the USE Questionnaire.

Results

For task errors, significant differences were found among ventilators (p<0.05) and the Evital 4 received higher task errors when compared to the Servo I (p<0.05). For blink rate, significant differences were found in tasks of starting the ventilator, ventilator monitoring values recognition, ventilator setting parameters modification, alarm parameter recognition, and resetting among ventilators (p<0.05). Furthermore, blink duration was also found to be significant differently in tasks of starting the ventilator, mode and setting parameters recognition, ventilator monitoring values recognition, ventilator mode modification, and alarm parameter recognition and resetting, as well as in the average of all tasks (p<0.05). For perceived workload, the Evital 4 received higher NASA-TLX scores among ventilators. For user experience, the Servo I received the highest scores on the USE Questionnaire among the ventilators.

Conclusions

The study provides a comprehensive evaluation method of user interface based on respiratory therapists’ performance, workload, and user experience. In addition, this study suggests that the ergonomic design of the Evital 4 is poor. Finally, we found that eye motion (blink rate and duration) may be useful to assess the ergonomics of a user interface.

Pediatric Early Warning Score Systems, Nurses Perspective - A Focus Group Study

PURPOSE

Pediatric early warning score (PEWS) systems are used to monitor pediatric patients' vital signs and facilitate the treatment of patients at risk of deteriorating. The aim of this study was to gain knowledge about nurses' experiences with PEWS and to highlight factors facilitating and impeding the use of PEWS tools in clinical practice.

DESIGN AND METHODS

An exploratory qualitative design was chosen using focus group interviews to gain a deeper understanding of nurses' experiences with PEWS. A total of five focus group interviews were conducted at three hospitals, and a qualitative meaning condensation analysis as described by Kvale and Brinkmann was performed.

RESULTS

Seven themes were identified, including i) lack of interdisciplinary awareness, ii) clinical judgment and PEWS-a multi-faceted approach, iii) PEWS supports a professional language, iv) monitoring the patient's - a challenge, v) PEWS helps to visualize the need for escalating care, vi) an inflexible and challenging tool, and vii) supportive tools enhance the nurses' experiences of PEWS positively.

CONCLUSIONS

Our findings suggest that attention should be given to nurses' perceptions of how both clinical judgment and PEWS should be seen as essential in providing nurses with information about the patients' conditions. If not, the risk of failing to recognize patients' deteriorating conditions will remain as this can have an impeding influence on nurses' use of PEWS. From the nurses' perspective, medical doctors seemed unaware of their role in using PEWS.

Clinician-Driven Design of VitalPAD-An Intelligent Monitoring and Communication Device to Improve Patient Safety in the Intensive Care Unit

The pediatric intensive care unit (ICU) is a complex environment, in which a multidisciplinary team of clinicians (registered nurses, respiratory therapists, and physicians) continually observe and evaluate patient information. Data are provided by multiple, and often physically separated sources, cognitive workload is high, and team communication can be challenging. Our aim is to combine information from multiple monitoring and therapeutic devices in a mobile application, the VitalPAD, to improve the efficiency of clinical decision-making, communication, and thereby patient safety. We observed individual ICU clinicians, multidisciplinary rounds, and handover procedures for 54 h to identify data needs, workflow, and existing cognitive aid use and limitations. A prototype was developed using an iterative participatory design approach; usability testing, including general and task-specific feedback, was obtained from 15 clinicians. Features included map overviews of the ICU showing clinician assignment, patient status, and respiratory support; patient vital signs; a photo-documentation option for arterial blood gas results; and team communication and reminder functions. Clinicians reported the prototype to be an intuitive display of vital parameters and relevant alerts and reminders, as well as a user-friendly communication tool. Future work includes implementation of a prototype, which will be evaluated under simulation and real-world conditions, with the aim of providing ICU staff with a monitoring device that will improve their daily work, communication, and decision-making capacity. Mobile monitoring of vital signs and therapy parameters might help improve patient safety in wards with single-patient rooms and likely has applications in many acute and critical care settings.

A Review of Visual Representations of Physiologic Data

Background

Physiological data is derived from electrodes attached directly to patients. Modern patient monitors are capable of sampling data at frequencies in the range of several million bits every hour. Hence the potential for cognitive threat arising from information overload and diminished situational awareness becomes increasingly relevant. A systematic review was conducted to identify novel visual representations of physiologic data that address cognitive, analytic, and monitoring requirements in critical care environments.

Objective

The aims of this review were to identify knowledge pertaining to (1) support for conveying event information via tri-event parameters; (2) identification of the use of visual variables across all physiologic representations; (3) aspects of effective design principles and methodology; (4) frequency of expert consultations; (5) support for user engagement and identifying heuristics for future developments.

Methods

A review was completed of papers published as of August 2016. Titles were first collected and analyzed using an inclusion criteria. Abstracts resulting from the first pass were then analyzed to produce a final set of full papers. Each full paper was passed through a data extraction form eliciting data for comparative analysis.

Results

In total, 39 full papers met all criteria and were selected for full review. Results revealed great diversity in visual representations of physiological data. Visual representations spanned 4 groups including tabular, graph-based, object-based, and metaphoric displays. The metaphoric display was the most popular (n=19), followed by waveform displays typical to the single-sensor-single-indicator paradigm (n=18), and finally object displays (n=9) that utilized spatiotemporal elements to highlight changes in physiologic status. Results obtained from experiments and evaluations suggest specifics related to the optimal use of visual variables, such as color, shape, size, and texture have not been fully understood. Relationships between outcomes and the users’ involvement in the design process also require further investigation. A very limited subset of visual representations (n=3) support interactive functionality for basic analysis, while only one display allows the user to perform analysis including more than one patient.

Conclusions

Results from the review suggest positive outcomes when visual representations extend beyond the typical waveform displays; however, there remain numerous challenges. In particular, the challenge of extensibility limits their applicability to certain subsets or locations, challenge of interoperability limits its expressiveness beyond physiologic data, and finally the challenge of instantaneity limits the extent of interactive user engagement.

The usability of ventilators: a comparative evaluation of use safety and user experience

Background

The design complexity of critical care ventilators (CCVs) can lead to use errors and patient harm. In this study, we present the results of a comparison of four CCVs from market leaders, using a rigorous methodology for the evaluation of use safety and user experience of medical devices.

Methods

We carried out a comparative usability study of four CCVs: Hamilton G5, Puritan Bennett 980, Maquet SERVO-U, and Dräger Evita V500. Forty-eight critical care respiratory therapists participated in this fully counterbalanced, repeated measures study. Participants completed seven clinical scenarios composed of 16 tasks on each ventilator.

Use safety was measured by percentage of tasks with use errors or close calls (UE/CCs). User experience was measured by system usability and workload metrics, using the Post-Study System Usability Questionnaire (PSSUQ) and the National Aeronautics and Space Administration Task Load Index (NASA-TLX).

Results

Nine of 18 post hoc contrasts between pairs of ventilators were significant after Bonferroni correction, with effect sizes between 0.4 and 1.09 (Cohen’s d). There were significantly fewer UE/CCs with SERVO-U when compared to G5 (p = 0.044) and V500 (p = 0.020). Participants reported higher system usability for G5 when compared to PB980 (p = 0.035) and higher system usability for SERVO-U when compared to G5 (p < 0.001), PB980 (p < 0.001), and V500 (p < 0.001). Participants reported lower workload for G5 when compared to PB980 (p < 0.001) and lower workload for SERVO-U when compared to PB980 (p < 0.001) and V500 (p < 0.001). G5 scored better on two of nine possible comparisons; SERVO-U scored better on seven of nine possible comparisons. Aspects influencing participants’ performance and perception include the low sensitivity of G5’s touchscreen and the positive effect from the quality of SERVO-U’s user interface design.

Conclusions

This study provides empirical evidence of how four ventilators from market leaders compare and highlights the importance of medical technology design. Within the boundaries of this study, we can infer that SERVO-U demonstrated the highest levels of use safety and user experience, followed by G5. Based on qualitative data, differences in outcomes could be explained by interaction design, quality of hardware components used in manufacturing, and influence of consumer product technology on users’ expectations.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1431-1) contains supplementary material, which is available to authorized users.

Hemodynamic monitoring in the era of digital health

Digital innovations are changing medicine, and hemodynamic monitoring will not be an exception. Five to ten years from now, we can envision a world where clinicians will learn hemodynamics with simulators and serious games, will monitor patients with wearable or implantable sensors in the hospital and after discharge, will use medical devices able to communicate and integrate the historical, clinical, physiologic and biological information necessary to predict adverse events, propose the most rationale therapy and ensure it is delivered properly. Considerable intellectual and financial investments are currently made to ensure some of these new ideas and products soon become a reality.

Evaluation of a configural vital signs display for intensive care unit nurses

OBJECTIVE

The objective was to evaluate a configural vital signs (CVS) display designed to support rapid detection and identification of physiological deterioration by graphically presenting patient vital signs data.

BACKGROUND

Current display technology in the intensive care unit (ICU) is not optimized for fast recognition and identification of physiological changes in patients. To support nurses more effectively, graphical or configural vital signs displays need to be developed and evaluated.

METHOD

A CVS display was developed based on findings from studies of the cognitive work of ICU nurses during patient monitoring. A total of 42 ICU nurses interpreted data presented either in a traditional, numerical format (n = 21) or on the CVS display (n = 21). Response time and accuracy in clinical data interpretation (i.e., identification of patient status) were assessed across four scenarios.

RESULTS

Data interpretation speed and accuracy improved significantly in the CVS display condition; for example, in one scenario nurses required only half of the time for data interpretation and showed up to 1.9 times higher accuracy in identifying the patient state compared to the numerical display condition.

CONCLUSION

Providing patient information in a configural display with readily visible trends and data variability can improve the speed and accuracy of data interpretation by ICU nurses.

APPLICATION

Although many studies, including this one, support the use of configural displays, the vast majority of ICU monitoring displays still present clinical data in numerical format. The introduction of configural displays in clinical monitoring has potential to improve patient safety.

Human Factors in Critical Care Medical Environments

The purpose of this chapter on human factors in critical care medical environments is to provide a systematic review of the human factors and ergonomics contributions that led to significant improvements in patient safety over the last five decades. The review will focus on issues that contributed to patient injury and fatalities and how human factors and ergonomics can improve performance of providers in critical care. Given the complexity of critical care delivery, a review needs to cover a wide range of subjects. In this review, I take a sociotechnical systems perspective on critical care and discuss the people, their technical and nontechnical skills, the importance of teamwork, technology, and ergonomics in this complex environment. After a description of the importance of a safety climate, the chapter will conclude with a summary on how human factors and ergonomics can improve quality in critical care delivery.

Decision support for hemodynamic management: from graphical displays to closed loop systems

The way hemodynamic therapies are delivered today in anesthesia and critical care is suboptimal. Hemodynamic variables are not always understood correctly and used properly. The adoption of hemodynamic goal-directed strategies, known to be clinically useful, is poor. Ensuring therapies are delivered effectively is the goal of decision support tools and closed loop systems. Graphical displays (metaphor screens) may help clinicians to better capture and integrate the multivariable hemodynamic information. This may result in faster and more accurate diagnosis and therapeutic decisions. Graphical displays (target screens) have the potential to increase adherence to goal-directed strategies and ultimately improve patients' outcomes, but this remains to be confirmed by prospective studies. Closed loop systems are the ultimate solution to ensure therapies are delivered. However, most therapeutic decisions cannot be based on a limited number of output variables. Therefore, one should focus on the development of systems designed to relieve clinicians from very simple and repetitive tasks. Whether intraoperative goal-directed fluid therapy may be one of these tasks remains to be evaluated.

Evaluation of the effect of information integration in displays for ICU nurses on situation awareness and task completion time: A prospective randomized controlled study

OBJECTIVE

The study measured whether nurses' situation awareness would increase and task completion time decrease when they used an integrated information display compared to traditional displays for medication management, patient awareness and team communication.

SETTING

The Burn Trauma Intensive Care Unit (BTICU) at the University Hospital, University of Utah Health Science Center, Salt Lake City, Utah, USA.

PARTICIPANTS

12 experienced BTICU nurses.

MEASURES

Situation awareness (accuracy of the participants' answer) and task completion time (response time from seeing the question to submitting the answer) were measured using paper prototypes of both displays.

STUDY DESIGN

Counter-balanced (on display order), repeated-measures design.

MAIN RESULTS

Nurses had a higher situation awareness when using the integrated display, with an overall accuracy of 85.3% compared to 61.8% with the traditional displays (odds ratio 3.61, P<.001, 95% CI=2.34…5.57). Task completion times were nearly half with integrated displays compared to traditional displays (median 26.0 and 42.1s, hazard ratio 2.31, P<.001, CI=1.83…2.93).

CONCLUSIONS

An integrated ICU information display increased nurses' situation awareness and decreased task completion time. Information integration has the potential to decrease errors, increase nurses' productivity and may allow nurses to react faster to a patient's clinical needs. Bidirectional device communication is needed for these displays to achieve full potential in improving patient safety.

Evaluation of an integrated intensive care unit monitoring display by critical care fellow physicians

In the past two far-view displays, which showed vital signs, trends, alarms, infusion pump status, and therapy support indicators, were developed and assessed by critical care nurses (Görges et al. in Dimens Crit Care Nurs. 30(4):206-17, 2011). The aim of the current study is to assess the generalizability of these findings to physicians. The first aim is to test whether an integrated far-view display, designed to be readable from 3 to 5 m, enables critical care physicians to more rapidly and accurately (1) recognize a change in patient condition; (2) identify alarms; and (3) identify near-empty infusion pumps, than a traditional patient monitor and infusion pump. A second aim is to test if the new displays reduce the mental workload required for this decision making. Fifteen critical care fellow physicians (median age of 34 years, with 2-8 years of ICU experience) were asked to use the three displays to compare the data from two patients and decide which patient required their attention first. Each physician made 60 decisions: 20 with each of the two far-view displays and 20 decisions with a standard patient monitor next to an infusion pump. A 41 and 26 % improvement in decision accuracy was observed with the bar and clock far-view displays, respectively. Specifically, the identification of near empty infusion pumps, a task normally performed by nurses, and patients with a single alarm were better with the new displays. Using the bar display physicians made their decision 12 % faster than when using the control display, a median improvement of 2.1 s. No significant differences were observed in measured workload. Displays that present patient data in a redesigned format enables critical care clinicians to more rapidly identify changes in patient conditions and to more accurately decide which patient needs their attention. In a clinical setting, this could improve patient safety. In future work, an evaluation of the display using live patient data from an ICU should be performed.

Informing the design of hemodynamic monitoring displays

In the ICU, an extensive array of variables from the hemodynamic monitoring display is routinely analyzed. However, the development of new display technologies is proceeding without adequate study of the monitoring tasks and behaviors of a primary user group--critical-care nurses. Semistructured interviews focusing on the cognitive aspects of the hemodynamic monitoring task were conducted with 14 critical-care nurses. A systematic content analysis of qualitative data identified cognitive tasks that had applicability to the design of monitoring displays. The cognitive tasks of hemodynamic monitoring were (1) selective data acquisition, (2) applying meaning to the variables and understanding relationships between parameters, (3) controlling hemodynamics by titrating medications and intravenous fluids, and (4) monitoring complex trends of multiple interacting variables and patient response to interventions. Recommendations include designing the monitoring display to match the mental constructs and cognitive tasks of the user by applying conceptual meaning to the variables, highlighting relationships between variables, and presenting a "big picture" view of the patient's condition. Monitoring displays must also present integrated trends that illustrate the dynamic relationship between interventions and patient response.

Evaluation of an integrated graphical display to promote acute change detection in ICU patients

OBJECTIVE

The purpose of this study was to evaluate ICU nurses' ability to detect patient change using an integrated graphical information display (IGID) versus a conventional tabular ICU patient information display (i.e. electronic chart).

DESIGN

Using participants from two different sites, we conducted a repeated measures simulator-based experiment to assess ICU nurses' ability to detect abnormal patient variables using a novel IGID versus a conventional tabular information display. Patient scenarios and display presentations were fully counterbalanced.

MEASUREMENTS

We measured percent correct detection of abnormal patient variables, nurses' perceived workload (NASA-TLX), and display usability ratings.

RESULTS

32 ICU nurses (87% female, median age of 29 years, and median ICU experience of 2.5 years) using the IGID detected more abnormal variables compared to the tabular display [F(1, 119)=13.0, p<0.05]. There was a significant main effect of site [F(1, 119)=14.2], with development site participants doing better. There were no significant differences in nurses' perceived workload. The IGID display was rated as more usable than the conventional display [F(1, 60)=31.7].

CONCLUSION

Overall, nurses reported more important physiological information with the novel IGID than tabular display. Moreover, the finding of site differences may reflect local influences in work practice and involvement in iterative display design methodology. Information displays developed using user-centered design should accommodate the full diversity of the intended user population across use sites.

Intensive care unit nurses' information needs and recommendations for integrated displays to improve nurses' situation awareness

OBJECTIVE

Fatal errors can occur in intensive care units (ICUs). Researchers claim that information integration at the bedside may improve nurses' situation awareness (SA) of patients and decrease errors. However, it is unclear which information should be integrated and in what form. Our research uses the theory of SA to analyze the type of tasks, and their associated information gaps. We aimed to provide recommendations for integrated, consolidated information displays to improve nurses' SA.

MATERIALS AND METHODS

Systematic observations methods were used to follow 19 ICU nurses for 38 hours in 3 clinical practice settings. Storyboard methods and concept mapping helped to categorize the observed tasks, the associated information needs, and the information gaps of the most frequent tasks by SA level. Consensus and discussion of the research team was used to propose recommendations to improve information displays at the bedside based on information deficits.

RESULTS

Nurses performed 46 different tasks at a rate of 23.4 tasks per hour. The information needed to perform the most common tasks was often inaccessible, difficult to see at a distance or located on multiple monitoring devices. Current devices at the ICU bedside do not adequately support a nurse's information-gathering activities. Medication management was the most frequent category of tasks.

DISCUSSION

Information gaps were present at all levels of SA and across most of the tasks. Using a theoretical model to understand information gaps can aid in designing functional requirements.

CONCLUSION

Integrated information that enhances nurses' Situation Awareness may decrease errors and improve patient safety in the future.

High concordance between expert anaesthetists' actions and advice of decision support system in achieving oxygen delivery targets in high-risk surgery patients

BACKGROUND

Goal-directed therapy has a secure place in perioperative care. Algorithms are based on Starling's law of the heart, notwithstanding that this does not numerically define volume or heart performance variables. These have been developed based on a Guytonian view of the circulation and are implemented in a computerized decision support system (Navigator™). We studied the feasibility and performance of the graphical display of the system in an intervention and a control group of patients undergoing major abdominal surgery.

METHODS

Patients were randomized to either graphically (intervention) or numerically (control) guided administration of therapy. Goals were set and treatments and concordance with guidance noted, where applicable. Anaesthesia was provided by one of three experienced anaesthetists well acquainted with Navigator™. The primary objective was to determine whether the use of graphical display decision support more efficiently enables the achievement of oxygen delivery targets. This was quantitated as percentage time in the target zone and averaged standardized distance from the target centre.

RESULTS

The mean percentage time in the target zone was 36.7% for control and 36.5% for intervention. The averaged standardized difference was 1.5 in control and 1.6 in intervention. There was no significant difference in fluid balances. There was a high level of concordance between decision support recommendation and anaesthetist action (84.3%).

CONCLUSIONS

In experienced hands, the addition of a graphical display for haemodynamic guidance resulted in a similar time in target and averaged standardized difference. The haemodynamic guidance system should be explored in a comparative study to anaesthesia management without guidance.

Continuously informing vibrotactile displays in support of attention management and multitasking in anesthesiology

OBJECTIVE

A novel vibrotactile display type was investigated to determine the potential benefits for supporting the attention and task management of anesthesiologists.

BACKGROUND

Recent research has shown physiological monitoring and multitasking performance can benefit from displaying patient data via alarm-like tactile notifications and via continuously informing auditory displays (e.g., sonifications). The current study investigated a novel combination of these two approaches: continuously informing tactile displays.

METHOD

A tactile alarm and two continuously informing tactile display designs were evaluated in an anesthesia induction simulation with anesthesiologists as participants. Several performance measures were collected for two tasks: physiological monitoring and anesthesia induction. A multitask performance score equivalently weighted components from each task, normalized across experimental scenarios. Subjective rankings of the displays were also collected.

RESULTS

Compared to the baseline (visual and auditory only) display configuration, each tactile display significantly improved performance in several objective measures, including multitask performance score. The continuously informing display that encoded the severity of patient health into the salience of its signals supported significantly better performance than the other two tactile displays. Contrasting the objective results, participants subjectively ranked the tactile alarm display highest.

CONCLUSION

Continuously informing tactile displays with alarm-like properties (e.g., salience mapping) can better support anesthesiologists' physiological monitoring and multitasking performance under the high task demands of anesthesia induction. Adaptive display mechanisms may improve user acceptance.

APPLICATION

This study can inform display design to support multitasking performance of anesthesiologists in the clinical setting and other supervisory control operators in work domains characterized by high demands for visual and auditory resources.

The effect of a graphical interpretation of a statistic trend indicator (Trigg's Tracking Variable) on the detection of simulated changes

Anaesthesia involves processing large amounts of information over time. One task of the anaesthetist is to detect substantive changes in physiological variables promptly and reliably. It has been previously demonstrated that a graphical trend display of historical data leads to more rapid detection of such changes. We examined the effect of a graphical indication of the magnitude of Trigg's Tracking Variable, a simple statistically based trend detection algorithm, on the accuracy and latency of the detection of changes in a micro-simulation. Ten anaesthetists each viewed 20 simulations with four variables displayed as the current value with a simple graphical trend display. Values for these variables were generated by a computer model, and updated every second; after a period of stability a change occurred to a new random value at least 10 units from baseline. In 50% of the simulations an indication of the rate of change was given by a five level graphical representation of the value of Trigg's Tracking Variable. Participants were asked to indicate when they thought a change was occurring. Changes were detected 10.9% faster with the trend indicator present (mean 13.1 [SD 3.1] cycles vs 14.6 [SD 3.4] cycles, 95% confidence interval 0.4 to 2.5 cycles, P = 0.013. There was no difference in accuracy of detection (median with trend detection 97% [interquartile range 95 to 100%], without trend detection 100% [98 to 100%]), P = 0.8. We conclude that simple statistical trend detection may speed detection of changes during routine anaesthesia, even when a graphical trend display is present.

A far-view intensive care unit monitoring display enables faster triage

Although nurses perform the majority of the clinical tasks in an intensive care unit, current patient monitors were not designed to support a nurse's workflow. Nurses constantly triage patients, deciding which patient is currently in the most need of care. To make this decision, nurses must observe the patient's vital signs and therapeutic device information from multiple sources. To obtain this information, they often have to enter the patient's room. This study addresses 3 hypotheses. Information provided by far-view monitoring displays (1) reduces the amount of time to determine which patient needs care first, (2) increases the accuracy of assigning priority to the right patient, and (3) reduces nurses mental workload. We developed 2 far-view displays to be read from a distance of 3 to 5 m without entering the patient's room. Both display vital signs, trends, alarms, infusion pump status, and therapy support indicators. To evaluate the displays, nurses were asked to use the displays to decide which of 2 patients required their attention first. They made 60 decisions: 20 with each far-view display and 20 decisions with a standard patient monitor next to an infusion pump. Sixteen nurses (median age of 27.5 years with 2.75 years of experience) participated in the study. Using the 2 far-view displays, nurses more accurately and rapidly identified stable patients and syringe pumps that were nearly empty. Median decision times were 11.3 and 12.4 seconds for the 2 far-view displays and 17.2 seconds for the control display. The 2 far-view displays reduced median decision-making times by 4.8 to 5.9 seconds, increased accuracy in assignment of priority in 2 of 7 patient conditions, and reduced nurses' frustration with the triaging task. In a clinical setting, the proposed far-view display might reduce nurses' mental workload and thereby increase patient safety.

Graphical arterial blood gas visualization tool supports rapid and accurate data interpretation

A visualization tool that integrates numeric information from an arterial blood gas report with novel graphics was designed for the purpose of promoting rapid and accurate interpretation of acid-base data. A study compared data interpretation performance when arterial blood gas results were presented in a traditional numerical list versus the graphical visualization tool. Critical-care nurses (n = 15) and nursing students (n = 15) were significantly more accurate identifying acid-base states and assessing trends in acid-base data when using the graphical visualization tool. Critical-care nurses and nursing students using traditional numerical data had an average accuracy of 69% and 74%, respectively. Using the visualization tool, average accuracy improved to 83% for critical-care nurses and 93% for nursing students. Analysis of response times demonstrated that the visualization tool might help nurses overcome the "speed/accuracy trade-off" during high-stress situations when rapid decisions must be rendered. Perceived mental workload was significantly reduced for nursing students when they used the graphical visualization tool. In this study, the effects of implementing the graphical visualization were greater for nursing students than for critical-care nurses, which may indicate that the experienced nurses needed more training and use of the new technology prior to testing to show similar gains. Results of the objective and subjective evaluations support the integration of this graphical visualization tool into clinical environments that require accurate and timely interpretation of arterial blood gas data.

Graphical arterial blood gas visualization tool supports rapid and accurate data interpretation

A visualization tool that integrates numeric information from an arterial blood gas report with novel graphics was designed for the purpose of promoting rapid and accurate interpretation of acid-base data. A study compared data interpretation performance when arterial blood gas results were presented in a traditional numerical list versus the graphical visualization tool. Critical-care nurses (n = 15) and nursing students (n = 15) were significantly more accurate identifying acid-base states and assessing trends in acid-base data when using the graphical visualization tool. Critical-care nurses and nursing students using traditional numerical data had an average accuracy of 69% and 74%, respectively. Using the visualization tool, average accuracy improved to 83% for critical-care nurses and 93% for nursing students. Analysis of response times demonstrated that the visualization tool might help nurses overcome the "speed/accuracy trade-off" during high-stress situations when rapid decisions must be rendered. Perceived mental workload was significantly reduced for nursing students when they used the graphical visualization tool. In this study, the effects of implementing the graphical visualization were greater for nursing students than for critical-care nurses, which may indicate that the experienced nurses needed more training and use of the new technology prior to testing to show similar gains. Results of the objective and subjective evaluations support the integration of this graphical visualization tool into clinical environments that require accurate and timely interpretation of arterial blood gas data.