Relationships among barodontalgia prevalence, altitude, stress, dental care frequency, and barodontalgia awareness: a survey of Turkish pilots

Background

Gas expansion in body cavities due to pressure changes at high altitudes can cause barodontalgia. This condition may compromise flight safety.

Aim

To investigate relationships among barodontalgia awareness, dental visit frequency, and barodontalgia prevalence in civilian and military pilots operating at high altitudes.

Materials and Methods

Civilian pilots from Turkish Airlines and military pilots from the Turkish Air Force, flying between November 2022 and January 2023, participated in this study. A 20-question survey was administered to 750 pilots, covering topics such as barodontalgia awareness, dental visit frequency, breaks after dental treatments, in-flight pain, and pain type and severity. The voluntary surveys were distributed by email.

Results

Of the 750 pilots, 526 completed the survey; 61% were aware of barodontalgia, and 81% of pilots who had experienced it reported pain at altitudes <2000 feet. The study revealed higher barodontalgia awareness among pilots who had experienced it, with the highest prevalence among jet pilots. Pilots with barodontalgia also showed a higher frequency of dental visits (p < 0.001). Additionally, this group reported more frequent interruption of flight due to dental treatment (IFDT), more problems experienced in flights after treatment (PFAT), and higher instances of bruxism or teeth clenching during flight, suggesting stress and anxiety (p < 0.05).

Conclusions

Barodontalgia, a type of pain linked to stress, significantly impacts pilot performance, and can threaten flight safety, even at lower altitudes. Thus, there is a need to educate pilots about stress management, barodontalgia awareness, and the importance of regular dental check-ups.

Relationship between sleep quality and gravitational Tolerance

BACKGROUND

The purpose of this study was to investigate the relationship between sleep quality and gravitational tolerance because sleep could directly affect physiological variables of the human body.

METHODS

For the present study, 157 male Korea Air Force Academy cadets were recruited. They were assigned into a gravity (G)-tolerance test pass group (GP, n = 87) and a G-tolerance test fail group (GF, n = 70). All participants were assessed for G-tolerance test and Pittsburgh Sleep Quality Index (PSQI), a self-report questionnaire. Physical fitness test was performed based on the physical fitness test of the Ministry of National Defense of Korea.

RESULTS

Independent t-test showed that PSQI global score (p < 0.001), PSQI sleep quality (p < 0.001), PSQI sleep onset latency (p = 0.009), PSQI sleep disturbance (p < 0.001), and PSQI daytime dysfunction (p < 0.001) were significantly different between the two groups. Participants with PSQI score less than 5 were more likely to have a longer G-tolerance test time (OR = 4.705, 95% CI = 2.00-11.05). Additionally, associations between those with PSQI score less than 5 (OR = 4.567, 95% CI = 1.94-10.74) were after adjusting (< 30 s and ≥ 30 s) for covariates. A negative correlation was found between G-tolerance test time and PSQI global score (p < 0.001). Negative correlations were found among 3 km running, push-up (p < 0.001), and sit-up (p < 0.001). A positive correlation was found between push-up and sit-up (p < 0.001).

CONCLUSION

In conclusion, participants with good sleep quality were 4.705 times more likely to have longer G-tolerance test time. Thus, it is important for aircraft pilots to manage their sleep quality. Pre-pilots should also improve their sleep quality to pass the G-tolerance test.

Return to flight duty (RTFD) after posterior lumbar spine surgery for symptomatic lumbar disc herniation (LDH) and lumbar isthmic spondylolisthesis (LIS) in Chinese military pilots

BACKGROUND

Symptomatic lumbar disc herniation (LDH) and lumbar isthmic spondylolisthesis (LIS) present significant challenges for military pilots, which may result in grounding if not effectively managed. Surgical treatment for LDH and LIS may offer a pathway to return to flight duty (RTFD), but recent data on this crucial topic is lacking. This study seeks to address this gap by investigating the RTFD outcomes among Chinese military pilots who have undergone lumbar spine surgery for symptomatic LDH and LIS.

METHODS

A retrospective review was conducted on active-duty military pilots who underwent isolated decompressive or fusion procedures at an authorized military medical center from March 1, 2007, to March 1, 2023. The analysis utilized descriptive statistics to examine demographic, occupational, surgical, and outcome data, with a particular focus on preoperative flight status, recommended clearance by spine surgeons, and actual RTFD outcomes and time.

RESULTS

Among the identified cases of active-duty military pilots with LDH or LIS treated by lumbar surgery (n = 24), 70.8% (17 of 24) consistently maintained RTFD status without encountering surgical complications or medical issues during the follow-up period. Of the seven pilots who did not RTFD, one retired within a year of surgery, two had anterior cruciate ligament injuries, three had residual radicular symptoms, and one had chronic low back pain. Excluding pilots who retired and did not RTFD for reasons unrelated to their lumbar conditions, the RTFD rate stood at 81.0% (17 of 21). The median time for recommended clearance by spine surgeons was 143.0 days (inter-quartile range, 116.5-196.0), while the median duration for actual RTFD attainment was 221.0 days (inter-quartile range, 182.0-300.0). The median follow-up post-lumbar surgery was 1.7 years (inter-quartile range, 0.4-2.9).

CONCLUSION

Most military pilots diagnosed with symptomatic LDH and LIS can continue their careers and regain active-duty flight status following lumbar spine surgery, as reflected by the high RTFD rate. Lumbar spine surgery can successfully alleviate the physical constraints associated with spinal conditions, facilitating the return of military pilots to their demanding profession.

Are the Pilots Onboard? Equipping Radiologists for Clinical Implementation of AI

The incorporation of artificial intelligence into radiological clinical workflow is on the verge of being realized. To ensure that these tools are effective, measures must be taken to educate radiologists on tool performance and failure modes. Additionally, radiology systems should be designed to avoid automation bias and the potential decline in radiologist performance. Designed solutions should cater to every level of expertise so that patient care can be enhanced and risks reduced. Ultimately, the radiology community must provide education so that radiologists can learn about algorithms, their inputs and outputs, and potential ways they may fail. This manuscript will present suggestions on how to train radiologists to use these new digital systems, how to detect AI errors, and how to maintain underlying diagnostic competency when the algorithm fails.

Consensus on the pharmacological treatment of acute stress disorder in Chinese pilots: a Delphi study

BACKGROUND

Appropriate medication is very important for pilots with acute stress disorder. Improper medication can not only affect the physical and mental health of the pilots but can also endanger flight safety. Hence, we aimed to quickly and effectively relieve symptoms and restore cognitive function by forming a consensus of Chinese experts on the pharmacological treatment of acute stress disorder in pilots using the Delphi method.

METHODS

Relevant literature was searched to enumerate the current status of pharmacological treatment of acute stress disorder in pilots, followed by two rounds of expert consultation and discussion according to the listed status of the survey using the Delphi method. A descriptive statistical method was used to analyze the basic information, authority coefficients, concentration of opinions, and survey items of the experts to develop a consensus on the pharmacological treatment of acute stress disorder in pilots.

RESULTS

A total of 16 experts in psychiatry, pharmacology, and aerospace medicine from different provinces and cities across China were invited for consultation. The recovery rate of the two rounds of consultation was 100%, and the expert authority coefficients were 0.897 and 0.906, respectively. Kendall's coefficient of concordance of indicators at all levels was 0.564-0.594 (p < 0.01). Based on the number of votes received, alprazolam tablets (16), eszopiclone tablets (15), and lorazepam tablets (14) were recommended for the treatment of excitatory psychomotor symptoms of acute stress disorder; paroxetine tablets (15) and sertraline tablets (15) were available for psychomotor depressive symptoms; olanzapine tablets (15), olanzapine orally disintegrating tablets (14), and quetiapine fumarate tablets (14) were selected for psychotic symptoms.

CONCLUSIONS

This study formed a consensus on rapid and effective pharmacological treatment for different symptoms of acute stress disorder pilots, which provides a reference for clinical treatment.

The impact of COVID-19 on maritime pilots: Evidence and lessons

The COVID-19 pandemic led to port congestion and disruption to global logistics and supply chains. While previous research has examined the impact on port performance and economics, social issues, such as the impact on port personnel (including pilots), have been overlooked. In this context, this paper examines the challenges experienced by Chinese pilots during the pandemic through in-depth interviews with 28 pilots. It shows that the draconian pandemic control measures adopted in China, rather than the pandemic itself, impaired pilots' physical and mental health, reduced their availability, and introduced new safety hazards, which curtailed both the port's capacity and ability to provide efficient and safe pilotage and resulted in sub-standard services. The findings suggest that there is a serious issue regarding the absence of effective mechanisms for pilots to raise their health and safety concerns and how these might be addressed by port administrators and/or local authorities. Worker participation and involvement in occupational health and safety management was problematic. These findings have implications for pilot station management at both company and government administrative and legislative levels.

Designing a generic, adaptive protocol resource for the measurement of health impact in cash transfer pilot and feasibility studies and trials in high-income countries

INTRODUCTION

In the context of the COVID-19 pandemic, upstream interventions that tackle social determinants of health inequalities have never been more important. Evaluations of upstream cash transfer trials have failed to capture comprehensively the impacts that such systems might have on population health through inadequate design of the interventions themselves and failure to implement consistent, thorough research measures that can be used in microsimulations to model long-term impact. In this article, we describe the process of developing a generic, adaptive protocol resource to address this issue and the challenges involved in that process. The resource is designed for use in high-income countries (HIC) but draws on examples from a UK context to illustrate means of development and deployment. The resource is capable of further adaptation for use in low- and middle-income countries (LMIC). It has particular application for trials of Universal Basic Income but can be adapted to those covering other kinds of cash transfer and welfare system changes.

METHODS

We outline two types of prospective intervention based on pilots and trials currently under discussion. In developing the remainder of the resource, we establish six key principles, implement a modular approach based on types of measure and their prospective resource intensity, and source (validated where possible) measures and baseline data primarily from routine collection and large, longitudinal cohort studies. Through these measures, we seek to cover all areas of health impact identified in our theoretical model for use in pilot and feasibility studies.

RESULTS

We find that, in general, self-reported measures alongside routinely collected linked respondent data may provide a feasible means of producing data capable of demonstrating comprehensive health impact. However, we also suggest that, where possible, physiological measures should be included to elucidate underlying biological effects that may not be accurately captured through self-reporting alone and can enable modelling of long-term health outcomes. In addition, accurate self-reported objective income data remains a challenge and requires further development and testing. A process of development and implementation of the resource in pilot and feasibility studies will support assessment of whether or not our proposed health outcome measures are acceptable, feasible and can be used with validity and reliability in the target population.

DISCUSSION

We suggest that while Open Access evaluation instruments are available and usable to measure most constructs of interest, there remain some areas for which further development is necessary. This includes self-reported wellbeing measures that require paid licences but are used in a range of nationally important longitudinal studies instead of Open Access alternatives.

Evaluating primary care transformation: Synthesis of findings from UK pilot project reviews

BACKGROUND

Pilot "new models" of primary care have been funded across the UK since 2015, through various national transformation funds. Reflections and syntheses of evaluation findings provide an additional layer of insight into "what works" in transforming primary care.

AIM

To identify good practice in policy design, implementation and evaluation for primary care transformation.

DESIGN & SETTING

A thematic analysis of existing pilot evaluations in England, Wales and Scotland.

METHOD

Ten papers presenting evaluations of three national pilot studies - the Vanguard programme in England, the Pacesetter programme in Wales and the National Evaluation of New Models of Primary Care in Scotland, UK - were thematically analysed, and findings synthesised in order to identify lessons learned and good practice.

RESULTS

Common themes emerged across studies in all three countries at project and policy level which can support or inhibit new models of care. At project level, these include: working with all stakeholders, including communities and front-line staff; providing the time, space and support necessary for the project to succeed; agreeing on clear objectives from the outset; support for data collection, evaluation and shared learning. At policy level, more fundamental challenges relate to the parameters for pilot projects - in particular, the typically short-term nature of funding, with an expectation of results within 2-3 years. Changing expectations about outcome measures or project guidance, part-way through project implementation, was also identified as a key challenge.

CONCLUSION

Primary care transformation requires co-production and a rich, contextual understanding of local needs and complexities. However, a mismatch between policy objectives (care redesign to better meet patient needs) and policy parameters (short timeframes) is often a significant challenge to success.

Analysis of two naval pilots’ ejection injuries: Two case reports

BACKGROUND

Recently, two naval pilots in a two-seat trainer jet were forced to eject urgently due to sudden mechanical failure during night-time training. They were both successfully rescued and sent to the hospital for emergency treatment. In this study, we investigate their ejection injuries and recovery process.

CASE SUMMARY

We analyzed the clinical data of the traumatic condition and recovery process from ejection injuries of two pilots who ejected from a failed trainer jet and survived. After being successfully rescued and sent to the hospital, they were diagnosed with multiple ejection injuries, including eye trauma, limb bone and joint injury, rib and spine injury, and so on. Both cases underwent fluid replacement, acid suppression, nutritional support, hemostasis, bone metabolism improvement, phlegm elimination, psychological measurement, blood circulation promotion and detumescence, physical therapy, and external fixation with braces for 1 mo before being discharged from hospital. They then recuperated in a sanatorium for 2 mo, and the related laboratory tests and supplementary examinations show that they recovered from all the above injuries. After successfully passing the psychological test and physical examination, they returned to flight duty 3 mo after ejection.

CONCLUSION

The causes and conditions of ejection injury in the pilots were very complex. Although they finally recovered quickly and were released, it also serves as a reminder that attention should be paid to pilots’ ejection and parachute training in order to significantly reduce ejection injury and improve the ejection success rate. In addition, air defense support personnel should strengthen search and rescue and on-site emergency measures, and locate and rescue pilots in distress as early as possible to reduce subsequent injuries.

Effect of Chinese pilots carbon emission trading scheme on enterprises' total factor productivity: The moderating role of government participation and carbon trading market efficiency

Based on the tightening regulation of carbon emissions, China has launched the pilot carbon emission trading scheme (CETS) since 2013. There is growing empirical evidence of the actual effect of CETS to promote enterprises' productivity which is characterized by total factor productivity (TFP). However, most studies ignored the further analysis of influence mechanisms. This paper aims to explore the impact of CETS on the TFP of enterprises and discuss the mediating role of government participation and carbon trading market efficiency. Using data from A-share listed enterprises from CETS-covered enterprises, this paper employed a combination of the propensity score matching (PSM) and difference-in-differences (DID) strategies and found that the CETS has a statistically significant positive impact on the TFP of enterprises, and the positive effect has been maintained for six years since its inception. The moderation analysis indicated that: (1) two dimensions of government participation in terms of the market incentive and government supervision significantly moderate the positive impact of CETS on TFP of enterprises; (2) two dimensions of carbon trading market efficiency in terms of the market scale and liquidity significantly moderates the positive impact of CETS on TFP of enterprises. In light of Chinese pilots CETS policy, the study highlights the important moderating roles of government participation and high carbon trading market efficiency on enterprise's TFP.

Exposure to hypoxia impairs helicopter pilots' awareness of environment

The purpose of the present study was to determine how hypoxia effects awareness of environment (AoE) in helicopter pilots operating at high altitude. Eight helicopter crews flew two operational flights in a flight simulator while breathing gas mixtures of 20.9% (equivalent to 0 m altitude) and 11.4% (equivalent to 4572 m or 15,000 ft altitude) oxygen in a single blinded, counterbalanced, repeated measures study. Each flight included five missions, during which environment items were introduced that the crews needed to be aware of, and respond to. In the 4572 m simulation, the crews missed overall 28 AoE items compared to 12 in the 0 m simulation (Z = -1.992; p = .046). In contrast, the crews' technical skills were not significantly effected by hypoxia. Remarkably, the majority of pilots did not notice they were hypoxic or recognise their hypoxia symptoms during the simulation flight at 4572 m. Practitioner summary We show that hypoxia has a detrimental effect on helicopter pilot's AoE and alertness. This can lead to an increased risk for flight safety. To mitigate this risk we recommend performing hypoxia training in a flight simulator, developing wearable systems for physiological monitoring of pilots and re-evaluating current altitude regulations. Abbreviations: ANOVA: Analysis of variance; AoE: awareness of environment; CSV: comma-separated values; HDU: helmet display unit; HR: heart rate; IQR: interquartile range; Mdn: median; NTS: non-technical skills; RNLAF: Royal Netherlands Air Force; PPM: parts per million; SpO2: oxygen saturation; SSS: Stanford sleepiness scale; TS: technical Skills.

A new mathematical model for determining optimal workforce planning of pilots in an airline company

This study aims to model a workforce-planning problem of pilot roles which include captain and first officer in an airline company and to make an efficient plan having maximal utilization of minimum workforce requirements. To tackle this problem, a mixed integer programming based a new mathematical model is proposed. The model considers different conditions such as employing pilots with different skill types, resignations, retirements, holidays of pilots, transitions between different skills regarding needs of the demands during the planning horizon. The application of the proposed approach is investigated using a case study with real-world data from an airline company in Turkey. The results show that a company can use transitions instead of new employment and this is a more suitable medium-term production and human resource planning decision.

Determining sample size for progression criteria for pragmatic pilot RCTs: the hypothesis test strikes back!

Background

The current CONSORT guidelines for reporting pilot trials do not recommend hypothesis testing of clinical outcomes on the basis that a pilot trial is under-powered to detect such differences and this is the aim of the main trial. It states that primary evaluation should focus on descriptive analysis of feasibility/process outcomes (e.g. recruitment, adherence, treatment fidelity). Whilst the argument for not testing clinical outcomes is justifiable, the same does not necessarily apply to feasibility/process outcomes, where differences may be large and detectable with small samples. Moreover, there remains much ambiguity around sample size for pilot trials.

Methods

Many pilot trials adopt a ‘traffic light’ system for evaluating progression to the main trial determined by a set of criteria set up a priori. We construct a hypothesis testing approach for binary feasibility outcomes focused around this system that tests against being in the RED zone (unacceptable outcome) based on an expectation of being in the GREEN zone (acceptable outcome) and choose the sample size to give high power to reject being in the RED zone if the GREEN zone holds true. Pilot point estimates falling in the RED zone will be statistically non-significant and in the GREEN zone will be significant; the AMBER zone designates potentially acceptable outcome and statistical tests may be significant or non-significant.

Results

For example, in relation to treatment fidelity, if we assume the upper boundary of the RED zone is 50% and the lower boundary of the GREEN zone is 75% (designating unacceptable and acceptable treatment fidelity, respectively), the sample size required for analysis given 90% power and one-sided 5% alpha would be around n = 34 (intervention group alone). Observed treatment fidelity in the range of 0–17 participants (0–50%) will fall into the RED zone and be statistically non-significant, 18–25 (51–74%) fall into AMBER and may or may not be significant and 26–34 (75–100%) fall into GREEN and will be significant indicating acceptable fidelity.

Discussion

In general, several key process outcomes are assessed for progression to a main trial; a composite approach would require appraising the rules of progression across all these outcomes. This methodology provides a formal framework for hypothesis testing and sample size indication around process outcome evaluation for pilot RCTs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-021-00770-x.

The influence of pilot's attention allocation on instrument reading during take-off: The mediating effect of attention span

The aim of this study was to examine the relationship among attention span, instrument reading, and eye movement mode. Sixteen pilots participated in procedural tests for attention span and instrument reading ability while completing simulated flight take-offs. Different instrument types corresponded to different reaction times - as response time increased, presentation time decreased. It can also be seen from the attention distribution of the instrument area in take-off that different instruments receive different attention resources. Breadth and attention span not only have a direct impact on the ability to read the table but also have a mediating effect on eye movement pattern during flight. The study found a direct relationship between attention span and instrument reading and also verified the impact of the two on attention allocation during take-off. The results suggest that integration training for attention ability with instrument reading may enable more efficient pilot performance.

Effects of acute mild hypoxia on cerebral blood flow in pilots

BACKGROUND

Pilots often face and need to overcome a diverse range of unfavorable conditions, of which hypoxic exposure is the most common. Studies have reported that hypoxia can induce a decrease in cerebral blood flow (CBF) in the brains of both humans and animals. Hypoxia and the associated cerebral hemodynamic changes can contribute to cognitive performance deficits that may endanger flight safety and increase the risk of accidents.

AIM

In this study, we aimed to identify region-specific alterations in CBF in male pilots after exposure to hypoxia.

MATERIAL AND METHODS

We used 3D pseudo-continuous arterial spin labeling sequences in 35 healthy male pilots (mean age: 30.6 ± 4.82 years) under simulated hypoxic conditions with a 3.0-T magnetic resonance imaging scanner. The generated CBF maps were measured and averaged in several regions of interest.

RESULTS

Hypoxia decreased CBF in various brain regions, including the right temporal and bilateral occipital lobes, the anterior and posterior lobes of the cerebellum, the culmen and declive, and the inferior semilunar lobule of the cerebellum.

CONCLUSION

These changes may impact the functional activity of the brains of pilots experiencing hypoxia in flight, but the related mechanisms require further investigation.

Sleepiness among personnel in the Norwegian Air Ambulance Service

Abstract

Purpose To examine the effects of shift work and extended working hours on sleepiness among pilots and Helicopter Emergency Medical Service (HEMS) crew members in the Norwegian Air Ambulance.

Methods

This field study investigated sleepiness during 3 consecutive weeks: the week before work, the work week, and the week after work. The pilots and HEMS crew members (N = 50) kept a wake diary during all 3 weeks and completed reaction time tests during the work week.

Results

The overall sleepiness scores were low during all 3 weeks. When comparing the 3 weeks, the lowest sleepiness levels were found for the work week. There was a small difference across work days, in which subjective sleepiness scores were highest the first duty day. No change in the reaction time tests was evident during the work week. The crew members reported being most sleepy at midnight, compared to all the other timepoints over the course of a duty day. Regarding workload and total work time, having larger workload was associated with lower sleepiness scores, while having higher total work time was associated with higher sleepiness score, both compared to the medium category.

Conclusions

The findings indicate that the work schedules and setting for this distinct occupational group do not seem to negatively affect the sleepiness levels.

Use of a Medical-Alert Accessory in CKD: A Pilot Study

BACKGROUND AND OBJECTIVES

Poor disease recognition may jeopardize the safety of CKD care. We examined safety events and outcomes in patients with CKD piloting a medical-alert accessory intended to improve disease recognition and an observational subcohort from the same population.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We recruited 350 patients with stage 2-5 predialysis CKD. The first (pilot) 108 participants were given a medical-alert accessory (bracelet or necklace) indicating the diagnosis of CKD and displaying a website with safe CKD practices. The subsequent (observation) subcohort (n=242) received usual care. All participants underwent annual visits with ascertainment of patient-reported events (class 1) and actionable safety findings (class 2). Secondary outcomes included 50% GFR reduction, ESKD, and death. Cox proportional hazards assessed the association of the medical-alert accessory with outcomes.

RESULTS

Median follow-up of pilot and observation subcohorts were 52 (interquartile range, 44-63) and 37 (interquartile range, 27-47) months, respectively. The frequency of class 1 and class 2 safety events reported at annual visits was not different in the pilot versus observation group, with 108.7 and 100.6 events per 100 patient-visits (P=0.13), and 38.3 events and 41.2 events per 100 patient visits (P=0.23), respectively. The medical-alert accessory was associated with lower crude and adjusted rate of ESKD versus the observation group (hazard ratio, 0.42; 95% confidence interval, 0.20 to 0.89; and hazard ratio, 0.38; 95% confidence interval, 0.16 to 0.94, respectively). The association of the medical-alert accessory with the composite endpoint of ESKD or 50% reduction GFR was variable over time but appeared to have an early benefit (up to 23 months) with its use. There was no significant difference in incidence of hospitalization, death, or a composite of all outcomes between medical-alert accessory users and the observational group.

CONCLUSIONS

The medical-alert accessory was not associated with incidence of safety events but was associated with a lower rate of ESKD relative to usual care.

Airplane pilot flight performance on 21 maneuvers in a flight simulator under varying carbon dioxide concentrations

BACKGROUND

Recent studies suggest that carbon dioxide has an impact on cognitive function performance of office workers at concentrations previously thought to be benign (1000-2500 ppm). The only available data for CO₂ on the flight deck indicate that the average CO₂ concentrations are typically <1000 ppm, but the 95th percentile concentration can be as high as 1400 ppm, depending on airplane type.

METHODS

We recruited 30 active commercial airline pilots to fly three 3-h flight segments in an FAA-approved flight simulator with each segment at a different CO₂ concentration on the flight deck (700, 1500, 2500 ppm). CO₂ concentrations were modified by introducing ultra-pure CO₂ into the simulator; ventilation rates remained the same for each segment. The pilots performed a range of predefined maneuvers of varying difficulty without the aid of autopilot, and were assessed by a FAA Designated Pilot Examiner according to FAA Practical Test Standards. Pilots and the Examiner were blinded to test conditions and the order of exposures was randomized.

RESULTS

Compared to segments at a CO₂ concentration of 2500 ppm, the odds of passing a maneuver as rated by the Examiner in the simulator were 1.52 (95% CI: 1.02-2.25) times higher when pilots were exposed to 1500 ppm and 1.69 (95% CI: 1.11-2.55) times higher when exposed to 700 ppm, controlling for maneuver difficulty, Examiner and order of maneuvers.

DISCUSSION

Examiner rating captured a wider range of performance indicators than output from the flight simulator, which can characterize only a few quantitative aspects of the flight performance. More broadly, these findings suggest that there is a direct effect of carbon dioxide on performance, independent of ventilation, with implications for many other indoor environments that routinely experience CO₂ concentrations above 1000 ppm.

Aspects of work organization and reduced sleep quality of airline pilots

Objective

To estimate the prevalence and association of work organization associated with poor sleep quality among airline pilots.

Methods

1234 airline pilots filled out an online questionnaire. Independent variables included demographic data, work organization aspects, health, and sleep information. A question derived from the Karolinska Sleep Questionnaire was used to obtain subjective sleep quality. Poisson regression with robust variance was performed.

Results

The prevalence of poor sleep quality was 48.2%. Poor sleep quality was associated with high frequency of technical delays, ≥ 5 consecutive night shifts, moderate and great need for recovery after work, difficulty commuting to work, being insufficiently physically active and sleeping 6-8 hours and < 6 hours on days off.

Conclusion

Pilots' daily work schedules, consisting of frequent delays, long working hours and perceived high work demands preventing adequate recovery were associated with poor sleep quality.

Equal to or better than: The application of statistical non-inferiority to fatigue risk management

In December 2014, the Federal Aviation Administration (FAA) completed a major revision of the rules and regulations governing flight and duty time in commercial aviation (Federal Aviation Regulation (FAR) Part 117). Scientists were included in the revision process and provided insights into sleep, sleep loss, the circadian rhythm, and their effects on performance that were incorporated into the new rule. If a planned flight was non-compliant with the regulation, for example if it exceeded flight and duty time limits, it could only be flown under an FAA-approved Fatigue Risk Management System (FRMS) as meeting an Alternative Method of Compliance (AMOC). One method that a flight could qualify as an AMOC is if it could be demonstrated empirically that it was as safe as or safer than a similar flight, designated the Safety Standard Operation (SSO), that was compliant with the regulation. In the present paper, we demonstrate the FRMS process using a comparison between a non-compliant AMOC flight from the US west coast to Australia and a compliant SSO flight from the US west coast to Taiwan. The AMOC was non-compliant because it exceeded the flight time limits in the prescriptive rule. Once a data collection exemption was granted by the FAA, both the outbound and inbound AMOC and SSO routes were studied on four Safety Performance Indicators (SPIs). The SPIs studied were inflight sleep, cognitive performance, self-reported fatigue, and self-reported sleepiness. These measures were made at top of descent (TOD), a critical phase of flight. The study was designed as a paired comparison. Forty volunteer pilots studied flew both the AMOC and the SSO flights for a total of 80 studied flights. Using statistical non-inferiority applied to the AMOC and SSO SPIs, we demonstrated, as required by the new rule, that the US-Australia AMOC flight was "as safe as, or safer than" the US-Taiwan SSO flight. In the context of FRMS, statistical non-inferiority is a concept and technique of great utility, straightforward in application, producing clear visual representations of the findings, and providing a direct answer to the question posed by the regulation - is the AMOC flight "as safe as, or safer than" the SSO.

Selecting trainee pilots: Predictive validity of the WOMBAT situational awareness pilot selection test

The WOMBAT pilot selection test is widely used to select candidates for pilot training programs. Despite use in many countries, little information is available regarding the predictive validity of the test. This study was designed to test the ability of the WOMBAT test to predict performance outcomes in a sample of ab-initio pilots. Sixty students commenced the study in 3 cohorts, and completed the WOMBAT test before their performance in the training program was evaluated through flight time to solo, flight time to licence level achievement, and instructor ratings of performance. Higher WOMBAT total scores were significantly related to reduced time to solo, achieving flight licences, as well as some early ratings of performance by flight instructors. Further research now needs to examine the exact nature of the skills and abilities that the test indexes in order to further improve pilot selection and training procedures.

Comments on "Incidence of cancer among licensed commercial pilots flying North Atlantic routes"

Gudmundsdottir et al. in their paper entitled "Incidence of cancer among licensed commercial pilots flying North Atlantic routes" published in Environmental Health have evaluated the effects of exposure to higher levels of cosmic radiation on cancer incidence in the pilots of commercial flights. Despite its remarkable strengths, the paper authored by Gudmundsdottir et al. has some shortcomings. The shortcomings of this paper such as not determining the shape of dose-response relationship for radiation-induced cancers, limitations in flight dose calculations, the weaknesses of CARI-6 as the program used by Gudmundsdottir et al. to estimate the effective dose of galactic cosmic rays, and the problems associated with unpredictable nature of the magnitude and duration of solar particle events are discussed.

Two phosphAte taRGets in End-stage renal disease Trial (TARGET): A Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

Hyperphosphatemia is common among recipients of maintenance dialysis and is associated with a higher risk of mortality and cardiovascular events. A large randomized trial is needed to determine whether lowering phosphate concentrations with binders improves patient-important outcomes. To inform such an effort we conducted a pilot randomized controlled trial.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a randomized controlled trial of prevalent hemodialysis recipients already receiving calcium carbonate as a phosphate binder at five Canadian centers between March 31, 2014 and October 2, 2014. Participants were randomly allocated to 26 weeks of an intensive phosphate goal of 2.33-4.66 mg/dl (0.75-1.50 mmol/L) or a liberalized target of 6.20-7.75 mg/dl (2.00-2.50 mmol/L) by titrating calcium carbonate using a dosing nomogram. The primary outcome was the difference in the change in serum phosphate from randomization to 26 weeks.

RESULTS

Fifty-three participants were randomized to the intensive group and 51 to the liberalized group. The median (interquartile range) daily dose of elemental calcium at 26 weeks was 1800 (1275-3000) mg in the intensive group, and 0 (0-500) mg in the liberalized group. The mean (SD) serum phosphate at 26 weeks was 4.53 (1.12) mg/dl (1.46 [0.36] mmol/L) in the intensive group and 6.05 (1.40) mg/dl (1.95 [0.45] mmol/L) in the liberalized group. Phosphate concentration in the intensive group declined by 1.24 (95% confidence interval, 0.75 to 1.74) mg/dl (0.40 [95% confidence interval, 0.24 to 0.56] mmol/L) compared with the liberalized group. There were no statistically significant differences between the two groups in the risk of hypercalcemia, hypocalcemia, parathyroidectomy, or major vascular events.

CONCLUSIONS

It is feasible to achieve and maintain a difference in serum phosphate concentrations in hemodialysis recipients by titrating calcium carbonate. A large trial is needed to determine if targeting a lower serum phosphate concentration improves patient-important outcomes.

Aerial pesticide application causes DNA damage in pilots from Sinaloa, Mexico

The use of pesticides in agricultural production originates residues in the environment where they are applied. Pesticide aerial application is a frequent source of exposure to pesticides by persons dedicated to agricultural practices and those living in neighboring communities of sprayed fields. The aim of the study was to assess the genotoxic effects of pesticides in workers occupationally exposed to these chemicals during their aerial application to agricultural fields of Sinaloa, Mexico. The study involved 30 pilots of airplanes used to apply pesticides via aerial application and 30 unexposed controls. Damage was evaluated through the micronucleus assay and by other nuclear abnormalities in epithelial cells of oral mucosa. The highest frequency ratios (FR) equal to 269.5 corresponded to binucleated cells followed by 54.2, corresponding to cells with pyknotic nuclei, 45.2 of cells with chromatin condensation, 3.7 of cells with broken-egg, 3.6 of cells with micronucleus, and 2.0 of karyolytic cells. Age, worked time, smoking, and alcohol consumption did not have significant influence on nuclear abnormalities in the pilots studied. Pesticide exposure was the main factor for nuclear abnormality results and DNA damage. Marked genotoxic damage was developed even in younger pilots with 2 years of short working period, caused by their daily occupational exposure to pesticides.

Carotid duplex ultrasound and transcranial Doppler findings in commercial divers and pilots

The risky working environments of divers and pilots, and the possible role of extreme ambient pressure in carotid stenosis, make ischemic stroke an important occupational concern among these professionals. In this study, we aimed to evaluate the association of being exposed to hyperbaric or hypobaric conditions with carotid artery stenosis by comparing common carotid intima-media thickness (CCIMT) and blood flow velocities of cerebral arteries in divers and pilots using carotid duplex ultrasound (CDUS) and transcranial Doppler (TCD). CDUS and transtemporal TCD were performed in 29 divers, 36 pilots and 30 control participants. Medical history, blood pressure, lipid profile and blood sugar were recorded to control the previously well-known risk factors of atherosclerosis. Findings of the CDUS and TCD [including: CCIMT and blood flow velocities of internal carotid artery (ICA), common carotid artery (CCA), and middle cerebral artery (MCA)] of divers and pilots were compared with those of the control group using regression analysis models. Both right and left side CCIMT were significantly higher in divers (P < 0.05) and pilots (P < 0.05) in comparison with the control group. Carotid index [peak systolic velocity (PSV) of ICA/PSV of CCA) of divers and pilots were also higher than the control group. TCD findings were not significantly different between divers, pilots, and the control group. Increased CCIMT and carotid index in diver and pilot groups appear to be suggestive of accelerated atherosclerosis of carotid artery in these occupational groups.

Neck and shoulder muscle activity and posture among helicopter pilots and crew-members during military helicopter flight

Neck pain among helicopter pilots and crew-members is common. This study quantified the physical workload on neck and shoulder muscles using electromyography (EMG) measures during helicopter flight. Nine standardized sorties were performed, encompassing: cruising from location A to location B (AB) and performing search and rescue (SAR). SAR was performed with Night Vision Goggles (NVG), while AB was performed with (AB+NVG) and without NVG (AB-NVG). EMG was recorded for: trapezius (TRA), upper neck extensors (UNE), and sternocleido-mastoid (SCM). Maximal voluntary contractions (MVC) were performed for normalization of EMG (MVE). Neck posture of pilots and crew-members was monitored and pain intensity of neck, shoulder, and back was recorded. Mean muscle activity for UNE was ∼10% MVE and significantly higher than TRA and SCM, and SCM was significantly lower than TRA. There was no significant difference between AB-NVG and AB+NVG. Muscle activity in the UNE was significantly higher during SAR+NVG than AB-NVG. Sortie time (%) with non-neutral neck posture for SAR+NVG and AB-NVG was: 80.4%, 74.5% (flexed), 55.5%, 47.9% (rotated), 4.5%, 3.7% (lateral flexed). Neck pain intensity increased significantly from pre- (0.7±1.3) to post-sortie (1.6±1.9) for pilots (p=0.028). If sustained, UNE activity of ∼10% MVE is high, and implies a risk for neck disorders.

Brominated flame retardant exposure of aircraft personnel

The use of brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) in aircraft is the result of high fire safety demands. Personnel working in or with aircraft might therefore be exposed to several BFRs. Previous studies have reported PBDE exposure in flight attendants and in passengers. One other group that may be subjected to significant BFR exposure via inhalation, are the aircraft maintenance workers. Personnel exposure both during flights and maintenance of aircraft, are investigated in the present study. Several BFRs were present in air and dust sampled during both the exposure scenarios; PBDEs, hexabromocyclododecane (HBCDD), decabromodiphenyl ethane (DBDPE) and 1,2-bis (2,4,6-tribromophenoxy) ethane. PBDEs were also analyzed in serum from pilots/cabin crew, maintenance workers and from a control group of individuals without any occupational aircraft exposure. Significantly higher concentrations of PBDEs were found in maintenance workers compared to pilots/cabin crew and control subjects with median total PBDE concentrations of 19, 6.8 and 6.6 pmol g(-1) lipids, respectively. Pilots and cabin crew had similar concentrations of most PBDEs as the control group, except for BDE-153 and BDE-154 which were significantly higher. Results indicate higher concentrations among some of the pilots compared to the cabin crew. It is however, evident that the cabin personnel have lower BFR exposures compared to maintenance workers that are exposed to such a degree that their blood levels are significantly different from the control group.

Comparison of antioxidant status between pilots and non-flight staff of the army force: pilots may need more vitamin C

OBJECTIVE

To compare the blood antioxidant levels and dietary antioxidant intakes between pilots and non-flight staff of the Army Force in The Islamic Republic of Iran.

METHODS

Thirty-seven helicopter pilots and 40 non-flight staff were included in this study. Their general characteristics were recorded and their weight, height, and waist circumference were measured. Their daily intake of energy and nutrients including antioxidants was assessed using a semi-quantitative food frequency questionnaire. Serum levels of total antioxidant capacity (TAC), malondialdehyde (MDA), and glutathione reductase (GR), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) in red blood cells were also measured.

RESULTS

The median erythrocytes SOD, serum MDA level and the mean serum level of TAC and erythrocytes GPx were significantly higher in pilots than in non-flight staff. The median vitamin C intake was significantly lower in pilots than in non-flight staff. The serum MDA levels were similar in non-flight staff and pilots when their vitamin C intake was ⋜168 mg and significantly lower in non-flight staff than in pilots when their vitamin C intake was >168 mg.

CONCLUSION

The serum MDA level is lower in non-flight staff than in pilots when their vitamin C intake level is high, indicating that pilots need more vitamin C than non-flight staff.

Fatigue on the flight deck: the consequences of sleep loss and the benefits of napping

The detrimental effects of fatigue in aviation are well established, as evidenced by both the number of fatigue-related mishaps and numerous studies which have found that most pilots experience a deterioration in cognitive performance as well as increased stress during the course of a flight. Further, due to the nature of the average pilot's work schedule, with frequent changes in duty schedule, early morning starts, and extended duty periods, fatigue may be impossible to avoid. Thus, it is critical that fatigue countermeasures be available which can help to combat the often overwhelming effects of sleep loss or sleep disruption. While stimulants such as caffeine are typically effective at maintaining alertness and performance, such countermeasures do nothing to address the actual source of fatigue - insufficient sleep. Consequently, strategic naps are considered an efficacious means of maintaining performance while also reducing the individual's sleep debt. These types of naps have been advocated for pilots in particular, as opportunities to sleep either in the designated rest facilities or on the flight deck may be beneficial in reducing both the performance and alertness impairments associated with fatigue, as well as the subjective feelings of sleepiness. Evidence suggests that strategic naps can reduce subjective feelings of fatigue and improve performance and alertness. Despite some contraindications to implementing strategic naps while on duty, such as sleep inertia experienced upon awakening, both researchers and pilots agree that the benefits associated with these naps far outweigh the potential risks. This article is a literature review detailing both the health and safety concerns of fatigue among commercial pilots as well as benefits and risks associated with strategic napping to alleviate this fatigue.

Measuring neurophysiological signals in aircraft pilots and car drivers for the assessment of mental workload, fatigue and drowsiness

This paper reviews published papers related to neurophysiological measurements (electroencephalography: EEG, electrooculography EOG; heart rate: HR) in pilots/drivers during their driving tasks. The aim is to summarise the main neurophysiological findings related to the measurements of pilot/driver's brain activity during drive performance and how particular aspects of this brain activity could be connected with the important concepts of "mental workload", "mental fatigue" or "situational awareness". Review of the literature suggests that exists a coherent sequence of changes for EEG, EOG and HR variables during the transition from normal drive, high mental workload and eventually mental fatigue and drowsiness. In particular, increased EEG power in theta band and a decrease in alpha band occurred in high mental workload. Successively, increased EEG power in theta as well as delta and alpha bands characterise the transition between mental workload and mental fatigue. Drowsiness is also characterised by increased blink rate and decreased HR values. The detection of such mental states is actually performed "offline" with accuracy around 90% but not online. A discussion on the possible future applications of findings provided by these neurophysiological measurements in order to improve the safety of the vehicles will be also presented.