A perspective on persistent toxicants in veterans and amyotrophic lateral sclerosis: identifying exposures determining higher ALS risk

Multiple studies indicate that United States veterans have an increased risk of developing amyotrophic lateral sclerosis (ALS) compared to civilians. However, the responsible etiological factors are unknown. In the general population, specific occupational (e.g. truck drivers, airline pilots) and environmental exposures (e.g. metals, pesticides) are associated with an increased ALS risk. As such, the increased prevalence of ALS in veterans strongly suggests that there are exposures experienced by military personnel that are disproportionate to civilians. During service, veterans may encounter numerous neurotoxic exposures (e.g. burn pits, engine exhaust, firing ranges). So far, however, there is a paucity of studies investigating environmental factors contributing to ALS in veterans and even fewer assessing their exposure using biomarkers. Herein, we discuss ALS pathogenesis in relation to a series of persistent neurotoxicants (often emitted as mixtures) including: chemical elements, nanoparticles and lipophilic toxicants such as dioxins, polycyclic aromatic hydrocarbons and polychlorinated biphenyls. We propose these toxicants should be directly measured in veteran central nervous system tissue, where they may have accumulated for decades. Specific toxicants (or mixtures thereof) may accelerate ALS development following a multistep hypothesis or act synergistically with other service-linked exposures (e.g. head trauma/concussions). Such possibilities could explain the lower age of onset observed in veterans compared to civilians. Identifying high-risk exposures within vulnerable populations is key to understanding ALS etiopathogenesis and is urgently needed to act upon modifiable risk factors for military personnel who deserve enhanced protection during their years of service, not only for their short-term, but also long-term health.

125 INTRODUCING AN IN SITU SIMULATION PROGRAMME IN AN INTENSIVE CARE UNIT

This North London hospital has a 14-bed Intensive Care Unit (ICU). As a small District General ICU, staff exposure to emergency scenarios can be infrequent. Lack of practice can lead to a reduction in staff confidence and knowledge when these scenarios are encountered, especially during the COVID pandemic. The ICU had not previously undertaken in situ multi-disciplinary team (MDT) simulation sessions on the unit.The aim of the study was to introduce a novel programme of MDT simulation sessions in the ICU and provide feedback with the aim of increasing both staff confidence in managing emergency scenarios and staff understanding of the impact of human factors.A team of ICU Simulation Champions created emergency scenarios that could occur in the ICU. Pre-simulation and post-simulation questionnaires were produced to capture staff opinion on topics including benefits and barriers to simulation training and confidence in managing ICU emergencies. Members of the ICU MDT would be selected to participate in simulation scenarios. Afterwards, debrief sessions would be facilitated by Simulation Champions and Airline Pilots with a particular focus on competence in managing the emergency and human factors elements, such as communication and leadership. Participants would then be surveyed with the post-simulation questionnaire.Nine simulation sessions were conducted between October 2020 and June 2021. The sessions occurred within the ICU during the working day in a designated bay with the availability of all standard ICU resources and involved multiple MDT members to aid fidelity. Feedback by Simulation Champions mainly focussed on knowledge related to the ICU emergency, whilst the Airline Pilots provided expert feedback on human factors training. Fifty-five staff members completed the pre-simulation questionnaire and 37 simulation participants completed the post-simulation questionnaire. Prior to simulation participation, 28.3% of respondents agreed they felt confident managing emergency scenarios on ICU – this figure increased to 54.1% following simulation participation. 94.4% of simulation participants agreed that their knowledge of human factors had improved following the simulation and 100% of participants wanted further simulation teaching. Figure 1 shows a thematic analysis of the responses from 31 participants who were questioned about perceived benefits from simulation teaching. Following the success of the programme, the Hospital Trust will continue to support and develop inter-speciality and inter-professional training, and have funded the appointment of an ICU Simulation Fellow to continue to lead and enhance future in situ simulation teaching on the ICU.

Sleep Disorders Among Commercial Airline Pilots

BACKGROUND: Over the next 20 yr, international market expansion will necessitate the production of new commercial airplanes and the recruitment of additional crewmembers and technicians. Research has proven that fatigue and lack of sleep are risk factors for impaired cognitive performance and human error. Pilots frequently report fatigue to their employers, which may be related to sleep disturbance. Airline pilots, in particular, often experience circadian desynchronization and other types of sleep disorders. Shift workers have been observed to be at higher risk of fatigue that affects their performance and alertness. In Saudi Arabia, sleep disorders among airline pilots are understudied and underreported. The primary objective of this study was to screen for and determine the risk of sleep disorders, fatigue, and depression among pilots.METHODS: A cross-sectional epidemiological study with national commercial pilots was conducted from March 2019 to March 2020 using validated questionnaires to screen for the risk of sleep disorders, fatigue, and depression.RESULTS: In total, 344 pilots participated in the study. Half the sample was at risk for insomnia and fatigue. Older and more experienced pilots were less likely to suffer impaired sleep quality, insomnia, sleepiness, fatigue, and depression. In total, 59 (17.2%) pilots were at high risk for sleep apnea.CONCLUSION: The current study found that pilots were at risk of developing sleep disorders. A more robust and objective assessment is warranted for screening.Alzehairi A, Alhejaili F, Wali S, Al Qassas I, Balkhyour M, Pandi-Perumal SR. Sleep disorders among commercial airline pilots. Aerosp Med Hum Perform. 2021; 92(12):937–944.

The Effects of a Brief Lifestyle Intervention on the Health of Overweight Airline Pilots during COVID-19: A 12-Month Follow-Up Study

The aim of this study was to perform a 12-month follow-up of health parameters after a 17-week lifestyle intervention in overweight airline pilots. A parallel-group (intervention and control) study was conducted amongst 72 overweight airline pilots (body mass index > 25) over a 12-month period following the emergence of COVID-19. The intervention group (n = 35) received a personalized dietary, sleep, and physical activity program over a 17-week period. The control group (n = 37) received no intervention. Measurements for subjective health (physical activity, sleep quality and quantity, fruit and vegetable intake, and self-rated health) via an electronic survey, and objective measures of body mass and blood pressure were taken at baseline and at 12 months. Significant interactions for group × time from baseline to 12-months were found for all outcome measures (p < 0.001). Body mass and mean arterial pressure significantly decreased in the intervention group when compared to the control group (p < 0.001). Outcome measures for subjective health (physical activity, sleep quality and quantity, fruit and vegetable intake, and self-rated health) significantly increased in the intervention group when compared to the control group (p < 0.001). Results provide preliminary evidence that a brief three-component healthy sleep, diet and physical activity intervention can elicit and sustain long-term improvements in body mass and blood pressure management, health behaviors, and perceived subjective health in pilots and may support quality of life during an unprecedented global pandemic.

Improving Airline Pilots’ Visual Scanning and Manual Flight Performance through Training on Skilled Eye Gaze Strategies

Poor cockpit monitoring has been identified as an important contributor to aviation accidents. Improving pilots’ monitoring strategies could therefore help to enhance flight safety. During two different sessions, we analyzed the flight performance and eye movements of professional airline pilots in a full-flight simulator. In a pre-training session, 20 pilots performed a manual approach scenario as pilot flying (PFs) and were classified into three groups according to their flight performance: unstabilized, standard, and most accurate. The unstabilized pilots either under- or over-focused various instruments. Their number of visual scanning patterns was lower than those of pilots who managed to stabilize their approach. The most accurate pilots showed a higher perceptual efficiency with shorter fixation times and more fixations on important primary flight instruments. Approximately 10 months later, fourteen pilots returned for a post-training session. They received a short training program and performed a similar manual approach as during the pre-training session. Seven of them, the experimental group, received individual feedback on their own performance and visual behavior (i.e., during the pre-training session) and a variety of data obtained from the most accurate pilots, including an eye-tracking video showing efficient visual scanning strategies from one of the most accurate pilots. The other seven, the control group, received general guidelines on cockpit monitoring. During the post-training session, the experimental group had better flight performance (compared to the control group), and its visual scanning strategies became more similar to those of the most accurate pilots. In summary, our results suggest that cockpit monitoring underlies manual flight performance and that it can be improved using a training program based mainly on exposure to eye movement examples from highly accurate pilots.

Now you see it, now you don’t: dynamism amplifies the typicality effect

Some safety events do not stabilise in a coherent state, presenting with transient or intermittent features. Such dynamism may pose problems for human performance, especially if combined with non-typical stimuli that are rarely encountered in everyday work. This may explain undesirable pilot behaviour and could be an important cognitive factor in recent aircraft accidents. Sixty-five airline pilots tested a real-world typicality gradient, composed of two cockpit events, a typical event, and a non-typical event, across two different forms of dynamism, a stable, single system transition, and an unstable, intermittent system transition. We found that non-typical event stimuli elicited a greater number of response errors and incurred an increased response latency when compared to typical event stimuli, replicating the typicality effect. These performance deteriorations were amplified when a form of unstable system dynamism was introduced. Typical stimuli were unaffected by dynamism. This indicates that dynamic, non-typical events are problematic for pilots and may lead to poor event recognition and response. Typical is advantageous, even if dynamic. Manufacturers and airlines should evolve pilot training and crew procedures to take account of variety in event dynamics.

Noncompliance and Decision-Making of Airline Pilots: An Analysis of Narratives From the Aviation Safety Reporting System

The purpose of this study was to identify self-reported flight deck noncompliance in aviation safety reports and explore the relationship between adaptive expertise, deliberate vs. non-deliberate actions (errors), and intentional vs. unintentional noncompliance. The heuristics for assessing adaptive thinking and behavior were based on subscales of the Adaptive Expertise Survey (AES; Fisher & Peterson, 2001). We analyzed a random sample of 200 ASRS reports from 2019 and coded them with respect to (a) whether they described intentional or unintentional noncompliance by one or more flightcrew members, (b) whether the decision making was deliberate, and (c) whether the decision-making process involved correlates of adaptive or routine (non-adaptive) expertise. We found that unintentional noncompliance was associated most frequently with non-deliberate actions and non-adaptive behaviors. Adaptive behaviors were strongly associated with deliberate actions and intentional noncompliance. Our on-going research to investigate adaptive expertise and its relationship with predictors of noncompliance is discussed.