National Aeronautics And Space Administration Task Load Index Scores Research Articles

Aerosol Box Use in Reducing Health Care Worker Contamination During Airway Procedures (AIRWAY) Study: Secondary Workload and Provider Outcomes in a Simulation-Based Trial.

An aerosol box aims to reduce the risk of healthcare provider (HCP) exposure to infections during aerosol generating medical procedures (AGMPs), but little is known about its impact on workload of team members. We conducted a secondary analysis of data from a prospective, multicenter, randomized controlled trial evaluating the impact of aerosol box use on patterns of HCP contamination during AGMPs. The objectives of this study are to: 1) evaluate the effect of aerosol box use on HCP workload, 2) identify factors associated with HCP workload when using an aerosol box, and 3) describe the challenges perceived by HCPs of aerosol box use. Simulation-based randomized trial, conducted from May to December 2021. Four pediatric simulation centers. Teams of two HCPs were randomly assigned to control (no aerosol box) or intervention groups (aerosol box). Each team performed three scenarios requiring different pediatric airway management (bag-valve-mask [BVM] ventilation, laryngeal mask airway [LMA] insertion, and endotracheal intubation [ETI] with video laryngoscopy) on a simulated COVID-19 patient. National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is a standard tool that measures subjective workload with six subscales. A total of 64 teams (128 participants) were recruited. The use of aerosol box was associated with significantly higher frustration during LMA insertion (28.71 vs. 17.42; mean difference, 11.29; 95% CI, 0.92-21.66; p = 0.033). For ETI, there was a significant increase in most subscales in the intervention group, but there was no significant difference for BMV. Average NASA-TLX scores were all in the "low" range for both groups (range: control BVM 23.06, sd 13.91 to intervention ETI 38.15; sd 20.45). The effect of provider role on workloads was statistically significant only for physical demand (p = 0.001). As the complexity of procedure increased (BVM → LMA → ETI), the workload increased in all six subscales (p < 0.05). The use of aerosol box increased workload during ETI but not with BVM and LMA insertion. Overall workload scores remained in the "low" range, and there was no significant difference between airway provider and assistant.

3D printing in anatomical lung segmentectomies: A randomized pilot trial

ObjectiveThis pilot study evaluated the impact of using a 3D printed model of the patient's bronchovascular lung anatomy on the mental workload and fatigue of surgeons during full thoracoscopic segmentectomy. DesignWe performed a feasibility pilot study of a prospective randomized controlled trial with 2 parallel arms. All included patients underwent digital 3D visual reconstruction of their bronchovascular anatomy and were randomized into the following two groups: Digital arm (only a virtual 3D model was available) and Digital + Object arm (both virtual and printed 3D models were available). The primary end-point was the surgeons’ mental workload measured using the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) score. SettingBetween October 28, 2020 and October 05, 2021, we successively investigated all anatomic segmentectomies performed via thoracoscopy in the Thoracic Department of the Montsouris Mutualiste Institute, except for S6 segmentectomies and S4+5 left bi-segmentectomies. ParticipantsWe assessed 102 patients for anatomical segmentectomy. Among the, 40 were randomly assigned, and 34 were deemed analysable, with 17 patients included in each arm. ResultsComparison of the two groups, each comprising 17 patients, revealed no statistically significant difference in primary or secondary end-points. The consultation of the visual digital model was significantly less frequent when a 3D printed model was available (6 versus 54 consultations, p = 0.001). Notably, both arms exhibited high NASA-TLX scores, particularly in terms of mental demand, temporal demand, and effort scores. ConclusionIn our pilot study, 3D printed models and digital 3D reconstructions for pre-operative planning had an equivalent effect on thoracoscopic anatomic segmentectomy for experienced surgeons. The originality of this study lies in its focus on the impact of 3D printing of bronchovascular anatomy on surgeons, rather than solely on the surgical procedure.

Factors influencing the mental health status of support nurses and their workload during the COVID-19 epidemic.

The authors used the National Aeronautics and Space Administration Task Load Index (NASA-TLX) and general health questionnaire to analyze the factors influencing the mental health status and the workload of support nurses during the COVID-19 epidemic. The authors conducted a cross-sectional survey of 349 support nurses in April-October 2022. Using QuestionStar, a powerful online survey tool, the authors administered surveys to the participants, collected data on the mental health status and workload of support nurses, and analyzed the influencing factors based on the collected data. A total of 316 questionnaires were successfully collected, with an effective rate of 98.75%. The proportion of support nurses with mental health problems was 25% and the value of the NASA-TLX questionnaire was: M±SD 68.91±7.28 pts. Multi-factor analysis revealed that the number of children, family support, and nursing support location were the influencing factors of mental health status, while the multivariate analysis revealed that the presence of symptoms, nursing support location, support work type, and total 12-item General Health Questionnaire (GHQ-12) score were the influencing factors of the workload of support nurses. Compared to their counterparts in the plains, nurses working in isolated plateau regions who were caring for children and lacked family support, were more likely to have mental health issues. There was a positive correlation between the changes in GHQ-12 and NASA-TLX scores of the study participants. Compared to their counterparts in the plains and the tropical regions, nurses working in plateau regions had a heavier workload. As part of the follow-up measures to prevent and treat patients impacted by the COVID-19 epidemic, it is important to improve the mental health evaluation, consultation, and treatment of the support nurses to guarantee the high quality of the first-line support work. Int J Occup Med Environ Health. 2023;36(6)761-72.

AQUACEL® Ag Advantage reduces the stress of postoperative packing removal after endoscopic sinus surgery

ObjectiveAfter Endoscopic Sinus Surgery (ESS), packing plays an important role in wound healing and hemostasis. However, the effect of the packing removal procedure on physician stress has not been evaluated. The purpose of this study was to evaluate physician stress during packing removal for patients treated with AQUACEL® Ag Advantage versus KALTOSTAT®. MethodsThis retrospective study included 15 patients who underwent packing with ESS for chronic rhinosinusitis performed at two centers; 9 were treated with AQUACEL® Ag Advantage and 6 were treated with KALTOSTAT®. Physician stress during packing removal was evaluated with the National Aeronautics and Space Administration-Task Load Index (NASA-TLX). The time required to remove the packing and the number of instruments used in the procedure were recorded. Postoperative bleeding (Boezaart bleeding score) and wound healing were graded. Patient symptoms on the day after surgery and pain during packing removal were assessed using a visual analog scale. ResultsComputed tomography scores, asthma complications, and blood eosinophil counts were significantly higher in the AQUACEL® Ag Advantage group. Patient symptoms on the day after surgery were not significantly different between the two groups. Physician stress during the task of packing removal was significantly lower in the AQUACEL® Ag Advantage group than in the KALTOSTAT® group (35.5 vs. 81.0, p=0.016) according to the NASA-TLX scores. The number of instruments used in the procedure was significantly lower in the AQUACEL® Ag Advantage group than in the KALTOSTAT® group (3.0 vs. 6.0, p=0.015). There were no significant differences in procedure time for packing removal, postoperative bleeding, wound healing, or patient pain at the time of packing removal between the groups. ConclusionPhysicians feel stressed about packing removal. In addition, AQUACEL® Ag Advantage is useful for packing after ESS, requiring fewer instruments for the procedure than KALTOSTAT® and reducing physician stress about the procedure. Level of evidenceLevel 3.

Measured task load in directed observers versus active participants undergoing high-fidelity simulation education in a critical care setting.

The use of directed observers in high-fidelity simulation education is increasingly common. While evidence suggests similar educational outcomes for directed observers compared to active participants in technical skills, it remains uncertain if this benefit also exists for senior clinicians, especially in mental workload. We sought to compare the workload between active participants and directed observers using an objective measure. We performed a prospective, repeated-measures observational study during the New South Wales Ambulance Aeromedical Operations induction training from 2019 to 2020. Participants included senior critical care doctors, paramedics, and nurses undergoing high-fidelity simulation of prehospital and interhospital aeromedical missions. Task load was measured using the National Aeronautics and Space Administration task load index (NASA-TLX) administered following each simulation debrief. Prehospital and interhospital simulations were compared separately by building a multilevel model for complete case and all study data. Post hoc comparisons of NASA-TLX score for each group were performed using estimated marginal means (EMMs). We enrolled 70 participants, comprising 49 physicians (70%), 19 paramedics (27%), and two flight nurses (3%). From the complete case analysis, statistically significant differences were observed for total NASA-TLX scores between active participants and directed observers in both prehospital (participant EMM 78, observer EMM 65, estimated difference -13, 95% confidence interval [CI] -20 to -7) and interhospital simulations (participant EMM 69, observer EMM 59, estimated difference -10, 95% CI -16 to -3). When all available data were included, the pattern of results did not change. In our sample of senior clinicians, the task load experienced by both active participants and directed observers in high-fidelity simulation education was high for both prehospital and interhospital simulation exercises. The statistically significant differences we report are unlikely to be practically significant. Our results support the use of directed observers when resource limitations do not allow all course attendees to participate in every simulation.

Mixed Reality Improves 3D Visualization and Spatial Awareness of Bone Tumors for Surgical Planning in Orthopaedic Oncology: A Proof of Concept Study.

In orthopedic oncology, computer navigation and 3D-printed guides facilitate precise osteotomies only after surgical exposure. Before surgeries start, it is challenging to mentally process and superimpose the virtual medical images onto patients' anatomy for preoperative surgical planning. Mixed Reality (MR) is an immersive technology merging real and virtual worlds, and users can interact with digital objects in real time. Through Head-Mounted Displays, surgeons directly visualize holographic models that overlaid on tumor patients. The technology may facilitate surgical planning before skin incisions. Nine bone tumor patients were included (July 2021 - Dec 2022). There were six primary bone sarcomas, two benign bone tumors, and one revision pelvic prosthesis. MR applications were created using patients' preoperative medical images. The surgeon examined each patient clinically using the conventional method of viewing 2D images and MR via HMD, Hololens 2. A Likert-Scale (LS) questionnaire and The National Aeronautics and Space Administration-Task Load Index (NASA-TLX) score were used to evaluate and compare the effectiveness of surgical planning and the surgeon's clinical cognitive workload for the two methods. The qualitative survey of the LS questionnaire suggested that the MR group had superior spatial awareness of tumors and was considered more effective as a preoperative planning tool than the conventional group. For NASA-TLX scores, the overall cognitive workload was lower in MR 3D hologram group than in the 2D Group for preoperative clinical assessment. When using MR technology with HMDs, the surgeon reported no discomfort. MR technology may improve 3D visualization and spatial awareness of bone tumors in patients' anatomies and may facilitate surgical planning before skin incisions in orthopedic oncology surgery. With less cognitive load and better ergonomics, surgeons can focus on patients and surgical tasks with MR technology. Further studies must investigate whether MR technology improves clinical outcomes.

Postprocedural Cognitive Load Measurement With Immediate Feedback to Guide Curriculum Development

BackgroundMethods to assess competency in cardiothoracic training are essential. Here, we report a system that allows us to better assess competency from the perspective of both the trainee and educator. We hypothesized that postprocedural cognitive burden measurement (by the trainee) with immediate feedback (from the educator) could aid in identifying barriers to the acquisition of skills and knowledge so that training curricula can be individualized. MethodsThe National Aeronautics and Space Administration Task Load Index (NASA-TLX), a validated instrument to measure cognitive load, was administered with an online platform after bronchoscopy, esophagogastroduodenoscopy, and video-assisted thoracoscopic surgery for 11 residents. Immediate postprocedure feedback and standardized debriefing occurred for each procedure. ResultsMean NASA-TLX scores were highest (indicating greater cognitive load) for esophagogastroduodenoscopy and video-assisted thoracoscopic surgery (P < .001). When comparing subscale measures, mental demand was significantly higher for video-assisted thoracoscopic surgery (P = .026) compared with the other procedures, whereas physical demand was highest for esophagogastroduodenoscopy (P = .018). Self-reported frustration was similar for all case types (P = .247). Cognitive burden decreased with a greater number of procedures for bronchoscopy (P = .027). Significant improvement was noted by the trainee at the end of the rotation in self-assessed procedural competency and preparedness for thoracic board topics (all P < .05). Postprocedure feedback by the attending surgeon correlated with more frequent completion of self-evaluations by the residents. ConclusionsLongitudinal assessment of cognitive load in combination with postprocedural feedback identified barriers to skill acquisition for both residents and educators. This information allows for individualized rotation development as a step toward a competency-based curriculum.

Comparison of Weighted and Unweighted Task Load Indices for Single-Site Surgery Tasks

Background: The National Aeronautics and Space Administration Task Load Index (NASA-TLX) a nd Surgery Task Load Index (SURG-TLX) are two subjective workload m easurement instruments. Both instruments provide unweighted andweightedworkload measurements. Weighted TLX m easures have seldomly been used byresearchers typically becauseof its high correlation with unweighted TLX a nd addedexperimentaltime to collect pairwise weightings. Therefore, theaim of thestudy wa s to compare weighted TLX scores with unweighted TLX scores and each’s sensitivity for demographic and experimentalfactors. Methods: Two simulated la paroscopic single site surgery tasks were completedusing four surgicalmethods by 25 participants. Pearson correlations, principle componentanalyses and mixed effect models were used to compare the unweightedandweighted TLXscores across tasks a nd methods. Results: There was a high correlation(r &gt; 0.950, p &lt; 0.001) betweentheunweighted TLXscores and the weighted TLX scores. The weighted TLX scores showed better sensitivity to both demographic and experimental factors for both TLX instruments. Conclusion: The overall weighted NASA-TLX and SURG-TLX scores differed from their respective unweighted scores even with a high correlation. The weighted TLXshowed potentialto better discriminate subjective workloadfor single-site ta sks. Future research is needed to identify and validatea more streamlinedweightingmethodparticularly for complex experimental taskslike single-site surgery.

Physiological and Cognitive Performance in F-22 Pilots During Day and Night Flying.

BACKGROUND: Many workers routinely transition between day and night shiftsincluding pilots, where night flights are commonly considered more stressful. The physiological toll from this transition is not fully understood, though fatigue is a factor in many aviation accidents. This research investigated the changes in physiological markers of stress and cognitive performance as F-22 pilots transitioned from day flying to night flying.METHODS: There were 17 fully-qualified F-22 pilots who took part in a 2-wk data collection using salivary swabs, wrist-worn activity monitors, the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) inventory, and a go/no-go (GNG) test.RESULTS: No differences were found in comparing day and night flying on the GNG reaction time/accuracy, NASA-TLX scores, or sleep quantity. Cortisol levels were significantly higher than civilian levels in all experimental conditions and control days. Participants had higher than predicted cortisol levels postflight in the day-flying condition and lower than predicted cortisol levels postflight in the night-flying condition, relative to levels from control day patterns. We also found smaller changes in cortisol (pre- to postflight) in the day-flying condition for those with more F-22 experience. Finally, we found a negative correlation between Perceived Stress Scale scores and age of pilots (r 0.72).DISCUSSION: We hypothesized that the night-flying environment would be more stressful, but our results disputed this claim. Our results suggest day flying elicits more of a stress response; however, a larger sample size is required to verify results. Preliminary findings of potential stress adaptation may suggest stress adaptation in the F-22 community needs further investigation.Combs EK, Dahlman AS, Shattuck NL, Heissel JA, Whitaker LR. Physiological and cognitive performance in F-22 pilots during day and night flying. Aerosp Med Hum Perform. 2021; 92(5):303311.

Psychometric Properties of NASA-TLX and Index of Cognitive Activity as Measures of Cognitive Workload in Older Adults.

Cognitive workload is increasingly recognized as an important determinant of performance in cognitive tests and daily life activities. Cognitive workload is a measure of physical and mental effort allocation to a task, which can be determined through self-report or physiological measures. However, the reliability and validity of these measures have not been established in older adults with a wide range of cognitive ability. The aim of this study was to establish the test–retest reliability of the National Aeronautics and Space Administration Task Load Index (NASA-TLX) and Index of Cognitive Activity (ICA), extracted from pupillary size. The convergent validity of these measures against event-related potentials (ERPs) was also investigated. A total of 38 individuals with scores on the Montreal Cognitive Assessment ranging between 17 and 30 completed a working memory test (n-back) with three levels of difficulty at baseline and at a two-week follow-up. The intraclass correlation coefficients (ICC) values of the NASA-TLX ranged between 0.71 and 0.81, demonstrating good to excellent reliability. The mean ICA scores showed fair to good reliability, with ICCs ranging between 0.56 and 0.73. The mean ICA and NASA-TLX scores showed significant and moderate correlations (Pearson’s r ranging between 0.30 and 0.33) with the third positive peak of the ERP at the midline channels. We conclude that ICA and NASA-TLX are reliable measures of cognitive workload in older adults. Further research is needed in dissecting the subjective and objective constructs of cognitive workload.

Validation of the Raw National Aeronautics and Space Administration Task Load Index (NASA-TLX) Questionnaire to Assess Perceived Workload in Patient Monitoring Tasks: Pooled Analysis Study Using Mixed Models.

BackgroundPatient monitoring is indispensable in any operating room to follow the patient’s current health state based on measured physiological parameters. Reducing workload helps to free cognitive resources and thus influences human performance, which ultimately improves the quality of care. Among the many methods available to assess perceived workload, the National Aeronautics and Space Administration Task Load Index (NASA-TLX) provides the most widely accepted tool. However, only few studies have investigated the validity of the NASA-TLX in the health care sector.ObjectiveThis study aimed to validate a modified version of the raw NASA-TLX in patient monitoring tasks by investigating its correspondence with expected lower and higher workload situations and its robustness against nonworkload-related covariates. This defines criterion validity.MethodsIn this pooled analysis, we evaluated raw NASA-TLX scores collected after performing patient monitoring tasks in four different investigator-initiated, computer-based, prospective, multicenter studies. All of them were conducted in three hospitals with a high standard of care in central Europe. In these already published studies, we compared conventional patient monitoring with two newly developed situation awareness–oriented monitoring technologies called Visual Patient and Visual Clot. The participants were resident and staff anesthesia and intensive care physicians, and nurse anesthetists with completed specialization qualification. We analyzed the raw NASA-TLX scores by fitting mixed linear regression models and univariate models with different covariates.ResultsWe assessed a total of 1160 raw NASA-TLX questionnaires after performing specific patient monitoring tasks. Good test performance and higher self-rated diagnostic confidence correlated significantly with lower raw NASA-TLX scores and the subscores (all P<.001). Staff physicians rated significantly lower workload scores than residents (P=.001), whereas nurse anesthetists did not show any difference in the same comparison (P=.83). Standardized distraction resulted in higher rated total raw NASA-TLX scores (P<.001) and subscores. There was no gender difference regarding perceived workload (P=.26). The new visualization technologies Visual Patient and Visual Clot resulted in significantly lower total raw NASA-TLX scores and all subscores, including high self-rated performance, when compared with conventional monitoring (all P<.001).ConclusionsThis study validated a modified raw NASA-TLX questionnaire for patient monitoring tasks. The scores obtained correctly represented the assumed influences of the examined covariates on the perceived workload. We reported high criterion validity. The NASA-TLX questionnaire appears to be a reliable tool for measuring subjective workload. Further research should focus on its applicability in a clinical setting.

Ergonomic Assessment of the Mental Workload Confronted by Surgeons during Laparoscopic Surgery

Although the mental workload confronted by laparoscopic surgeons is rather high, there is presently no reliable, established method for evaluating this workload. In the present study, four evaluation indices of eye movement metrics were applied to evaluate surgeons' mental workload. Correlations between these indices and National Aeronautics and Space Administration Task Load Index (NASA-TLX) scores were also explored. Sixteen participants were recruited to complete four laparoscopic procedures. Eye movement was recorded during the tasks, and NASA-TLX scales were also introduced for subjective evaluation. The data were analyzed using R 3.3.2. Significant differences in the mental workload of each task were observed. Statistically significant correlations between mean pupil diameter change and NASA-TLX scores were also observed. The correlation coefficients were 0.763, 0.675, 0.405, and 0.547, and the P values correspondingly were 0.001, 0.004, 0.12, and 0.028, respectively. The results clarify that the mental workload of laparoscopic surgeons is dependent on the specific demands of the operation. Appropriate objective physiological indices can be used to identify the mental workload state of the surgeon.

Optimizing Mental Workload by Functional Near-Infrared Spectroscopy Based Dynamic Difficulty Adjustment.

Gains of cognitive training may be eliminated due to mental fatigue. This paper reports the design and implementation of a functional near-infrared spectroscopy (fNIRS) - dynamic difficulty adjustment (DDA) system. A total of 25 healthy volunteers underwent two training sessions - one with fixed difficulty level of training (FDT) and one with neurofeedback training (NFT) using our fNIRS-DDA system. The workload in each training session was assessed using the National Aeronautics and Space Administration Task Load Index (NASA-TLX). Whilst sustaining mental task performance, the drop in oxygenation level observed in NFT subjects might indicate mental fatigue as they received higher NASA-TLX scores, especially in both mental demand and frustration subscales. In contrast, the oxygenation levels remained almost constant by NFT subjects throughout the experiment. This suggests that the proposed fNIRS-DDA system aided the participants in avoiding mental fatigue. Future studies will investigate if the system may prevent the progression of Alzheimer's disease.

Augmented real‐time navigation with critical structure proximity alerts for endoscopic skull base surgery

Image-guided surgery (IGS) systems are frequently utilized during cranial base surgery to aid in orientation and facilitate targeted surgery. We wished to assess the performance of our recently developed localized intraoperative virtual endoscopy (LIVE)-IGS prototype in a preclinical setting prior to deployment in the operating room. This system combines real-time ablative instrument tracking, critical structure proximity alerts, three-dimensional virtual endoscopic views, and intraoperative cone-beam computed tomographic image updates. Randomized-controlled trial plus qualitative analysis. Skull base procedures were performed on 14 cadaver specimens by seven fellowship-trained skull base surgeons. Each subject performed two endoscopic transclival approaches; one with LIVE-IGS and one using a conventional IGS system in random order. National Aeronautics and Space Administration Task Load Index (NASA-TLX) scores were documented for each dissection, and a semistructured interview was recorded for qualitative assessment. The NASA-TLX scores for mental demand, effort, and frustration were significantly reduced with the LIVE-IGS system in comparison to conventional navigation (P < .05). The system interface was judged to be intuitive and most useful when there was a combination of high spatial demand, reduced or absent surface landmarks, and proximity to critical structures. The development of auditory icons for proximity alerts during the trial better informed the surgeon while limiting distraction. The LIVE-IGS system provided accurate, intuitive, and dynamic feedback to the operating surgeon. Further refinements to proximity alerts and visualization settings will enhance orientation while limiting distraction. The system is currently being deployed in a prospective clinical trial in skull base surgery.

Relating physician’s workload with errors during radiation therapy planning

PurposeTo relate subjective workload (WL) levels to errors for routine clinical tasks. Methods and MaterialsNine physicians (4 faculty and 5 residents) each performed 3 radiation therapy planning cases. The WL levels were subjectively assessed using National Aeronautics and Space Administration Task Load Index (NASA-TLX). Individual performance was assessed objectively based on the severity grade of errors. The relationship between the WL and performance was assessed via ordinal logistic regression. ResultsThere was an increased rate of severity grade of errors with increasing WL (P value = .02). As the majority of the higher NASA-TLX scores, and the majority of the performance errors were in the residents, our findings are likely most pertinent to radiation oncology centers with training programs. ConclusionsWL levels may be an important factor contributing to errors during radiation therapy planning tasks.

Augmented Real-Time Navigation with Critical Structure Proximity Alerts for Endoscopic Skull Base Surgery

Objectives/Hypothesis Image-guided surgery (IGS) systems are frequently utilized during cranial base surgery to aid in orientation and facilitate targeted surgery. We wished to assess the performance of our recently developed localized intraoperative virtual endoscopy (LIVE)-IGS prototype in a preclinical setting prior to deployment in the operating room. This system combines real-time ablative instrument tracking, critical structure proximity alerts, three-dimensional virtual endoscopic views, and intraoperative cone-beam computed tomographic image updates. Study Design Randomized-controlled trial plus qualitative analysis. Methods Skull base procedures were performed on 14 cadaver specimens by seven fellowship-trained skull base surgeons. Each subject performed two endoscopic transclival approaches; one with LIVE-IGS and one using a conventional IGS system in random order. National Aeronautics and Space Administration Task Load Index (NASA-TLX) scores were documented for each dissection, and a semistructured interview was recorded for qualitative assessment. Results The NASA-TLX scores for mental demand, effort, and frustration were significantly reduced with the LIVE-IGS system in comparison to conventional navigation (P < .05). The system interface was judged to be intuitive and most useful when there was a combination of high spatial demand, reduced or absent surface landmarks, and proximity to critical structures. The development of auditory icons for proximity alerts during the trial better informed the surgeon while limiting distraction. Conclusions The LIVE-IGS system provided accurate, intuitive, and dynamic feedback to the operating surgeon. Further refinements to proximity alerts and visualization settings will enhance orientation while limiting distraction. The system is currently being deployed in a prospective clinical trial in skull base surgery. Laryngoscope, 124:853–859, 2014

Higher Mental Workload is Associated With Poorer Laparoscopic Performance as Measured by the NASA-TLX Tool

Increased workload during task performance may increase fatigue and facilitate errors. The National Aeronautics and Space Administration-Task Load Index (NASA-TLX) is a previously validated tool for workload self-assessment. We assessed the relationship of workload and performance during simulator training on a complex laparoscopic task. NASA-TLX workload data from three separate trials were analyzed. All participants were novices (n = 28), followed the same curriculum on the fundamentals of laparoscopic surgery suturing model, and were tested in the animal operating room (OR) on a Nissen fundoplication model after training. Performance and workload scores were recorded at baseline, after proficiency achievement, and during the test. Performance, NASA-TLX scores, and inadvertent injuries during the test were analyzed and compared. Workload scores declined during training and mirrored performance changes. NASA-TLX scores correlated significantly with performance scores (r = -0.5, P < 0.001). Participants with higher workload scores caused more inadvertent injuries to adjacent structures in the OR (r = 0.38, P < 0.05). Increased mental and physical workload scores at baseline correlated with higher workload scores in the OR (r = 0.52-0.82; P < 0.05) and more inadvertent injuries (r = 0.52, P < 0.01). Increased workload is associated with inferior task performance and higher likelihood of errors. The NASA-TLX questionnaire accurately reflects workload changes during simulator training and may identify individuals more likely to experience high workload and more prone to errors during skill transfer to the clinical environment.