Looks can be deceiving: Gaze pattern differences between novices and experts during placement of central lines

Where do ICU trainees really look? An eye-tracking analysis of gaze patterns during central venous catheter insertion

BACKGROUND

There is limited knowledge about gaze patterns of intensive care unit (ICU) trainee doctors during the insertion of a central venous catheter (CVC). The primary objective of this study was to examine visual patterns exhibited by ICU trainee doctors during CVC insertion. Additionally, the study investigated whether differences in gaze patterns could be identified between more and less experienced trainee doctors.

METHODS

In a real-life, prospective observational study conducted at the interdisciplinary ICU at the University Hospital Zurich, Switzerland, ICU trainee doctors underwent eye-tracking during CVC insertion in a real ICU patient. Using mixed-effects model analyses, the primary outcomes were dwell time, first fixation duration, revisits, fixation count, and average fixation time on different areas of interest (AOI). Secondary outcomes were above eye-tracking outcome measures stratified according to experience level of participants.

RESULTS

Eighteen participants were included, of whom 10 were inexperienced and eight more experienced. Dwell time was highest for CVC preparation table (p = 0.02), jugular vein on ultrasound image (p < 0.001) and cervical puncture location (p < 0.001). Concerning experience, dwell time and revisits on jugular vein on ultrasound image (p = 0.02 and p = 0.04, respectively) and cervical puncture location (p = 0.004 and p = 0.01, respectively) were decreased in more experienced ICU trainees.

CONCLUSIONS

Various AOIs have distinct significance for ICU trainee doctors during CVC insertion. Experienced participants exhibited different gaze behavior, requiring less attention for preparation and handling tasks, emphasizing the importance of hand-eye coordination.

Initial Experience of Using First-Person Wearable Video Recording Technology During Central Venous Catheter Placement in the Cardiac Operating Room

OBJECTIVE

The aim of this study was to use wearable video-recording technology to measure precisely the timing of discrete events during perioperative central venous catheter (CVC) placements.

DESIGN

A single-center, observational, exploratory study on the use of wearable video-recording technology during intraoperative CVC placement.

SETTING

The study was conducted at a University Hospital.

PARTICIPANTS

Clinical anesthesia residents, cardiothoracic anesthesia fellows, and attending anesthesiologists participated in this study.

INTERVENTIONS

Participants were asked to use eye-tracking glasses prior to the placement of a CVC in the cardiac operating rooms. No other instruction was given to the participants.

MEASUREMENTS AND MAIN RESULTS

The authors measured the total time to complete the CVC placement, phase-specific time, and specific times of interest. They compared these times across 3 training levels and tested differences with analysis of variance. The authors' findings indicated significant differences in total CVC placement time when the procedure included a pulmonary artery catheter insertion (1,170 ± 364, 923 ± 272, and 596 ± 226 seconds; F2,63 = 12.71, p < 0.0001). Additionally, they found differences in interval times and times of interest. The authors observed a reduction of variability with increasing experience during the CVC placement phase.

CONCLUSIONS

In this observational study, the study authors describe their experience using first-person wearable video-recording technology to precisely measure the timing of discrete events during CVC placement by anesthesia residents and anesthesiologists. Future work will leverage the eye-tracking capabilities of the existing hardware to identify areas of inefficiency to develop actionable targets for interventions that could improve trainee performance and patient safety.

Clinical Outcomes of Standardized Central Venous Catheterization Simulation Training: A Comparative Analysis

OBJECTIVE

A standardized ultrasound-guided Internal Jugular Central Venous Catheterization (US-IJCVC) using online- and simulation-based training was first designed and then large-scale deployed at a teaching hospital institution to improve CVC surgical education. To understand the impact that the standardized training might have on patient complications, this study focuses on identifying the impact of the integration of an iteratively designed US-IJCVC training on clinical complications at a teaching hospital.

DESIGN AND PARTICIPANTS

A comparative study was conducted using TriNetX, a global health research network. Using Current Procedural Terminology (CPT) codes and the International Statistical Classification of Diseases and Related Health Problems (ICD-10) codes, we identified the total number of patients with a CVC and mechanical, infectious, and thrombosis complications with and without billable ultrasound between July 1 to June 30 in 2016, 2017, and 2022.

SETTING

A teaching hospital institution in Pennsylvania.

RESULTS

Results showed a correlation between years and complications indicating, (1) mechanical complications billable ultrasound, (2) infectious complications billable ultrasound, and (3) thrombosis complications billable ultrasound were significantly lower with the large-scale deployment. Results also showed that (4) mechanical, infectious, and thrombosis complications with and without billable ultrasound are within the range that prior work has reported.

CONCLUSION

These results indicate that there has been a decrease in mechanical, infectious, and thrombosis complications, which correlates with the US-IJCVC training large-scale deployment.

Shifting Perspectives: A proposed framework for analyzing head-mounted eye-tracking data with dynamic areas of interest and dynamic scenes

Eye-tracking is a valuable research method for understanding human cognition and is readily employed in human factors research, including human factors in healthcare. While wearable mobile eye trackers have become more readily available, there are no existing analysis methods for accurately and efficiently mapping dynamic gaze data on dynamic areas of interest (AOIs), which limits their utility in human factors research. The purpose of this paper was to outline a proposed framework for automating the analysis of dynamic areas of interest by integrating computer vision and machine learning (CVML). The framework is then tested using a use-case of a Central Venous Catheterization trainer with six dynamic AOIs. While the results of the validity trial indicate there is room for improvement in the CVML method proposed, the framework provides direction and guidance for human factors researchers using dynamic AOIs.

A sensor-based framework for layout and workflow assessment in operating rooms

Due to their large sizes and impediments to personnel workflows, integrating robotic technologies into the existing operating rooms (OR) is a challenge. In this study, we developed an ultra-wideband sensor-based human-machine-environment framework for layout and workflow assessments within the OR. In addition to providing best practices for use of the framework, we also demonstrated its effectiveness in understanding layout and workflow inefficiencies in 12 robotic-assisted surgeries (RAS) across 4 different surgical specialties. We found avoidable movements as the circulating nurse covers at least twice the distance of any other OR personnel before the patient cart (robot) is docked. OR areas of congestion and undesirable personnel-pair proximities across RAS phases that impose extra non-technical skill challenges were determined. Our findings highlight several implications for the added complexity of integrating robotic technologies into the OR, which can serve as drivers for objective evidence-based recommendations to combat RAS OR layout and workflow inefficiencies.

Preparing for the lasting effects of COVID-19 on medical training: The design and pilot study of a low-fidelity virtual reality prototype for Central Venous Catheterization training

Over the last several decades we have seen a shift from in-person to online training that has been exasperated by the COVID-19 pandemic. Researchers believe that many of these effects will be lasting which makes it even more important that the Human Factors community seek to step back and understand how to best train complex skills in a virtual world. The current paper is focused on understanding the utility of Virtual Reality (VR) in medical education for a hands-on procedural heavy procedure - ultrasound-guided Internal Jugular Central Venous Catheterization. Specifically, the objective of this study is to identify the potential utility of VR in US-IJCVC training through the design of a low-fidelity prototype and user interviews with three subject-matter experts. Results showed that the VR prototype designed is useful and provides a depth of knowledge and educational value which can be used to design innovative VR training approaches.

Eye Tracking Use in Surgical Research: A Systematic Review

INTRODUCTION

Eye tracking (ET) is a popular tool to study what factors affect the visual behaviour of surgical team members. To our knowledge, there have been no reviews to date that evaluate the broad use of ET in surgical research. This review aims to identify and assess the quality of this evidence, to synthesize how ET can be used to inform surgical practice, and to provide recommendations to improve future ET surgical studies.

METHODS

In line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic literature review was conducted. An electronic search was performed in MEDLINE, Cochrane Central, Embase, and Web of Science databases up to September 2020. Included studies used ET to measure the visual behaviour of members of the surgical team during surgery or surgical tasks. The included studies were assessed by two independent reviewers.

RESULTS

A total of 7614 studies were identified, and 111 were included for data extraction. Eleven applications were identified; the four most common were skill assessment (41%), visual attention assessment (22%), workload measurement (17%), and skills training (10%). A summary was provided of the various ways ET could be used to inform surgical practice, and three areas were identified for the improvement of future ET studies in surgery.

CONCLUSIONS

This review provided a comprehensive summary of the various applications of ET in surgery and how ET could be used to inform surgical practice, including how to use ET to improve surgical education. The information provided in this review can also aid in the design and conduct of future ET surgical studies.

Skill Characterisation of Sonographer Gaze Patterns during Second Trimester Clinical Fetal Ultrasounds using Time Curves

We present a method for skill characterisation of sonographer gaze patterns while performing routine second trimester fetal anatomy ultrasound scans. The position and scale of fetal anatomical planes during each scan differ because of fetal position, movements and sonographer skill. A standardised reference is required to compare recorded eye-tracking data for skill characterisation. We propose using an affine transformer network to localise the anatomy circumference in video frames, for normalisation of eye-tracking data. We use an event-based data visualisation, time curves, to characterise sonographer scanning patterns. We chose brain and heart anatomical planes because they vary in levels of gaze complexity. Our results show that when sonographers search for the same anatomical plane, even though the landmarks visited are similar, their time curves display different visual patterns. Brain planes also, on average, have more events or landmarks occurring than the heart, which highlights anatomy-specific differences in searching approaches.

Visualising Spatio-Temporal Gaze Characteristics for Exploratory Data Analysis in Clinical Fetal Ultrasound Scans

Visualising patterns in clinicians' eye movements while interpreting fetal ultrasound imaging videos is challenging. Across and within videos, there are differences in size an d position of Areas-of-Interest (AOIs) due to fetal position, movement and sonographer skill. Currently, AOIs are manually labelled or identified using eye-tracker manufacturer specifications which are not study specific. We propose using unsupervised clustering to identify meaningful AOIs and bi-contour plots to visualise spatio-temporal gaze characteristics. We use Hierarchical Density-Based Spatial Clustering of Applications with Noise (HDBSCAN) to identify the AOIs, and use their corresponding images to capture granular changes within each AOI. Then we visualise transitions within and between AOIs as read by the sonographer. We compare our method to a standardised eye-tracking manufacturer algorithm. Our method captures granular changes in gaze characteristics which are otherwise not shown. Our method is suitable for exploratory data analysis of eye-tracking data involving multiple participants and AOIs.

Correlating Personal Resourcefulness and Psychomotor Skills: An Analysis of Stress, Visual Attention and Technical Metrics

Modern surgical education is focused on making use of the available technologies in order to train and assess surgical skill acquisition. Innovative technologies for the automatic, objective assessment of nontechnical skills are currently under research. The main aim of this study is to determine whether personal resourcefulness can be assessed by monitoring parameters that are related to stress and visual attention and whether there is a relation between these and psychomotor skills in surgical education. For this purpose, we implemented an application in order to monitor the electrocardiogram (ECG), galvanic skin response (GSR), gaze and performance of surgeons-in-training while performing a laparoscopic box-trainer task so as to obtain technical and personal resourcefulness' metrics. Eight surgeons (6 nonexperts and 2 experts) completed the experiment. A total of 22 metrics were calculated (7 technical and 15 related to personal resourcefulness) per subject. The average values of these metrics in the presence of stressors were compared with those in their absence and depending on the participants' expertise. The results show that both the mean normalized GSR signal and average surgical instrument's acceleration change significantly when stressors are present. Additionally, the GSR and acceleration were found to be correlated, which indicates that there is a relation between psychomotor skills and personal resourcefulness.

Biomechanical analysis of expert anesthesiologists and novice residents performing a simulated central venous access procedure

BACKGROUND

Central venous access (CVA) is a frequent procedure taught in medical residencies. However, since CVA is a high-risk procedure requiring a detailed teaching and learning process to ensure trainee proficiency, it is necessary to determine objective differences between the expert's and the novice's performance to guide novice practitioners during their training process. This study compares experts' and novices' biomechanical variables during a simulated CVA performance.

METHODS

Seven experts and seven novices were part of this study. The participants' motion data during a CVA simulation procedure was collected using the Vicon Motion System. The procedure was divided into four stages for analysis, and each hand's speed, acceleration, and jerk were obtained. Also, the procedural time was analyzed. Descriptive analysis and multilevel linear models with random intercept and interaction were used to analyze group, hand, and stage differences.

RESULTS

There were statistically significant differences between experts and novices regarding time, speed, acceleration, and jerk during a simulated CVA performance. These differences vary significantly by the procedure stage for right-hand acceleration and left-hand jerk.

CONCLUSIONS

Experts take less time to perform the CVA procedure, which is reflected in higher speed, acceleration, and jerk values. This difference varies according to the procedure's stage, depending on the hand and variable studied, demonstrating that these variables could play an essential role in differentiating between experts and novices, and could be used when designing training strategies.

Procedural Telementoring in Rural, Underdeveloped, and Austere Settings: Origins, Present Challenges, and Future Perspectives

Telemedicine is perhaps the most rapidly growing area in health care. Approximately 15 million Americans receive medical assistance remotely every year. Yet rural communities face significant challenges in securing subspecialist care. In the United States, 25% of the population resides in rural areas, where less than 15% of physicians work. Current surgery residency programs do not adequately prepare surgeons for rural practice. Telementoring, wherein a remote expert guides a less experienced caregiver, has been proposed to address this challenge. Nonetheless, existing mentoring technologies are not widely available to rural communities, due to a lack of infrastructure and mentor availability. For this reason, some clinicians prefer simpler and more reliable technologies. This article presents past and current telementoring systems, with a focus on rural settings, and proposes aset of requirements for such systems. We conclude with a perspective on the future of telementoring systems and the integration of artificial intelligence within those systems.

The evaluation of eye gaze using an eye tracking system in simulation training of real-time ultrasound-guided venipuncture

PURPOSE

Real-time ultrasound (RTUS)-guided central venipuncture using the short-axis approach is complicated and likely to result in losing sight of the needle tip. Therefore, we focused on the eye gaze in our evaluation of the differences in eye gaze between medical students and experienced participants using an eye tracking system.

METHODS

Ten medical students (MS group), five residents (R group) and six pediatric surgeon fellows (F group) performed short-axis RTUS-guided venipuncture simulation using a modified vessel training system. The eye gaze was captured by the tracking system (Tobii Eye Tacker 4C) and recorded. The evaluation endpoints were the task completion time, total time and number of occurrences of the eye tracking marker outside US monitor and success rate of venipuncture.

RESULT

There were no significant differences in the task completion time and total time of the tracking marker outside the US monitor. The number of occurrences of the eye tracking marker outside US monitor in the MS group was significantly higher than in the F group (MS group: 9.5 ± 3.4, R group: 6.0 ± 2.9, F group: 5.2 ± 1.6; p = 0.04). The success rate of venipuncture in the R group tended to be better than in the F group.

CONCLUSION

More experienced operators let their eye fall outside the US monitor fewer times than less experienced ones. The eye gaze was associated with the success rate of RTUS-guided venipuncture. Repeated training while considering the eye gaze seems to be pivotal for mastering RTUS-guided venipuncture.

A Training Program for Real-Time Ultrasound-Guided Catheterization of the Subclavian Vein

PURPOSE

To develop and implement a comprehensive program to train providers to place subclavian central venous catheters (CVCs) using real-time ultrasound guidance.

STUDY DESIGN

Simulation-based prospective study at an academic medical center. Of 228 anesthesia providers and intensivists eligible to participate, 106 participants voluntarily enrolled. The training program consisted of a didactic module, hands-on instruction and practice using a CVC simulator and a standardized patient. The success of the program was measured by pre and post knowledge tests and direct observation during the hands-on sessions.

RESULTS

Of 106 participants who enrolled, 70 successfully completed the program. Out of 20 possible procedure steps, an average of 17.8 ± 2.9 were correctly performed in the simulated environment. The average time to needle insertion, defined by positive aspiration of stained saline, was 3.35 ± 3.02 min and the average time to wire insertion with ultrasound confirmation was 3.85 ± 3.12 min.

CONCLUSIONS

Participants learned how to successfully perform ultrasound-guided catheterization of the subclavian vein. Since ultrasound-guided subclavian CVC placement is a useful clinical skill that many practitioners are unfamiliar with, increasing competence and comfort with this procedure is an important goal. Other centers could consider adopting an approach similar to ours to train their providers to perform this technique.

Age-Related Differences in Fixation Pattern on a Companion Robot

Recent studies have addressed the various benefits of companion robots and expanded the research scope to their design. However, the viewpoints of older adults have not been deeply investigated. Therefore, this study aimed to examine the distinctive viewpoints of older adults by comparing them with those of younger adults. Thirty-one older and thirty-one younger adults participated in an eye-tracking experiment to investigate their impressions of a bear-like robot mockup. They also completed interviews and surveys to help us understand their viewpoints on the robot design. The gaze behaviors and the impressions of the two groups were significantly different. Older adults focused significantly more on the robot's face and paid little attention to the rest of the body. In contrast, the younger adults gazed at more body parts and viewed the robot in more detail than the older adults. Furthermore, the older adults rated physical attractiveness and social likeability of the robot significantly higher than the younger adults. The specific gaze behavior of the younger adults was linked to considerable negative feedback on the robot design. Based on these empirical findings, we recommend that impressions of older adults be considered when designing companion robots.

Feasibility and Utility of an Eye-Tracking Device for Assessing Teachers of Invasive Bedside Procedures

Patient-related complications from invasive bedside procedures (IBPs) are attributed to the experience and proficiency of the operator. Furthermore, IBP complications by trainees may be due to practice variability and competency among IBP teachers. The use of gaze metrics technology to better understand the behaviors of IBP teachers may aid in the creation of faculty development checklists and, ultimately, reduce procedural complications. Prior research on gaze patterns has focused on the individual performing the procedure, but the goal of this pilot study was to assess gaze behaviors of supervising teachers of IBPs, which is a paradigm shift within procedural education. In this study, pulmonary and critical care medicine fellows placed a central venous catheter on a simulated task trainer as pulmonary and critical care medicine faculty supervised while wearing an eye-tracking device. Both quantitative and qualitative data were obtained. Gaze analysis was divided into 2 areas of interest (ultrasonography and procedure site) and 3 procedural tasks (venous puncture, dilation, and flushing the line). Study findings included the following: (1) calibration was easy and took seconds to complete, (2) the device is relatively comfortable and did not interfere with tasks, (3) a trend toward a higher fixation frequency and dwell time on the ultrasound images during the puncture segment, and (4) variations in fixation frequency on the ultrasound images among supervising IBP teachers. This study documents the feasibility of the eye-tracking device for assessing behaviors of supervisory IBP teachers. There may be a signal suggesting differences in gaze patterns among supervisory teachers, which warrants further study.