The rate of iatrogenic injuries in surgical patients appears resistant to multiple interventions: what can we learn from aviation safety?

BACKGROUND: This project analyses all iatrogenic injuries from our department over the last decade and tracks their rate against several interventions. METHODS: All patients who sustained an iatrogenic injury between 2012 and 2022 were reviewed. RESULTS: A total of 946 iatrogenic injuries occurred in 731 patients. Sixty per cent of these patients were male; the median age was 39 years. Of 946 injuries, 574 (60.7%) occurred during an operation, and 372 (39.3%) were not related to an operation. Of the operative injuries 412 (71.8%) were enteric injuries. Of the 372 non-operative iatrogenic injuries 304 (82%) were due to indwelling devices (ID), and 34 (10%) occurred during flexible endoscopy. Fifty-five per cent of the injuries due to ID were due to central venous catheters (CVC) and urinary catheters (UC). CVC contributed toward 31% of all non-operation related iatrogenic injuries. One in 54 admissions (946/51 178) and one in 47 (574 /27 342) patients undergoing an operation sustained an iatrogenic injury. The annual rate of iatrogenic injuries did not decrease over the decade despite a multifaceted approach to reduce them. Interventions included electronic database development, procedural standardisation, and checklist implementation. CONCLUSION: Despite multiple interventions over a decade, our rate of iatrogenic injury remains constant. Ongoing multifaceted efforts to reduce this rate must focus on engendering a culture of safety at all levels of healthcare if we hope to match the enviable safety record of the aeronautics industry.

Study on the temporal and spatial relationship between public health events and the development of air transport scale: A case of the Southwest China.

The spread of the COVID-19 had profoundly affected the development of the air transportation. In order to determine the changes in air transportation volume associated with the development of the epidemic, this paper takes Southwest China as the study area. Monthly data and methods, such as the coefficient of variation, rank-size analysis and spatial matching index, were applied. The results found that: (1) during 2020-2022, there was a positive relationship between passenger volume and epidemic development, while freight volume increased for most airports in the first quarter of 2020-2022, particularly in the eastern region; (2) From the perspective of changes in air transportation volume under the development of the COVID-19, among various types of airports, the changes in transportation volume of main trunk airports were more significant than those of regional feeder airports in remote areas; (3) however, under the influence of the epidemic, main trunk airports still exhibited stronger attraction in passenger volume. That is to say, the passengers who chose to travel by air still tended to choose the main trunk airports and formed the agglomeration distribution pattern which around high-level airports in the provincial capital. Whereas the freight volume had a tendency of equalization among airports in Southwest China; (4) Over the course of time, the consistency of the spatial distribution of the number of cases and the passenger or freight volume in southwest China gradually increased. Among them, the spatial matching rate of the passenger volume and the number of COVID-19 cases was always higher than that of the cases and freight volume, which might indicate that there was a stronger correlation relationship. Therefore, it is proposed that the construction of multi-center airport system should be strengthened, the resilience of the route network for passenger transportation should be moderately enhanced, and the risk-resistant capacity of mainline airports and airports in tourist cities should be upgraded, so as to provide references for the orderly recovery of civil aviation and regional development.

Scenario analysis of energy consumption and related emissions in the transportation industry-a case study of Shaanxi Province.

In the context of pursuing carbon neutrality and balancing the use of fossil fuels with renewable energy, the transportation industry faces the challenge of accurately predicting energy demand, related emissions, and assessing the effectiveness of energy technologies and policies. This is crucial for formulating energy management plans and reducing carbon dioxide (CO2) and atmospheric pollutant emissions. Currently, research on energy consumption and emission forecasting primarily relies on energy consumption quantities and emission factors, which lack precision. This study employs the low emissions analysis platform (LEAP) model, utilizing a "bottom-up" modeling approach combined with scenario analysis to predict and analyze the energy demand and related emissions in the transportation industry. Compared to previous studies, the methodological framework proposed in this research offers higher precision and can explore energy-saving and emission-reduction pathways for different modes of transport, providing a valuable energy forecasting tool for transport policy formulation in other regions. The forecast results indicate that under the business-as-usual (BAU) scenario, by 2049, the energy consumption and related emissions in Shaanxi Province's transportation industry are expected to increase by 1.15 to 1.85 times compared to the baseline year. In the comprehensive (CP) scenario, the industry is projected to reach a carbon peak around 2033. The study also finds that energy consumption and emissions predominantly originate from private passenger vehicles, highway freight, and civil aviation passenger, which have the greatest potential for emission reduction under the transport structure optimized (TSO) scenario. Therefore, policymakers should consider regional development characteristics, combine different transportation modes, and specifically analyze the emission reduction potential of the transportation industry in various regions, formulating corresponding reduction policies accordingly.

Sleep Inertia in Aviation.

INTRODUCTION: Sleep inertia is the transition state during which alertness and cognitive performance are temporarily impaired after awakening. Magnitude and time course of sleep inertia are characterized by high individual variability with large differences between the cognitive functions affected. This period of impairment is of concern to pilots, who take sleep or nap periods during on-call work hours or in-flight rest, then need to perform safety-critical tasks soon after waking. This review analyzes literature related to sleep inertia and countermeasures applicable for aviation.METHODS: The large part of scientific literature that focuses on sleep inertia is based on studies in patients with chronic sleep inertia. We analyzed 8 narrative reviews and 64 papers related to acute sleep inertia in healthy subjects.DISCUSSION: Sleep inertia is a multifactorial, complex process, and many different protocols have been conducted, with a low number of subjects, in noncontrolled laboratory designs, with questionnaires or cognitive tests that have not been replicated. Evidence suggests that waking after sleep loss, or from deeper stages of sleep, can exacerbate sleep inertia through complex interactions between awakening and sleep-promoting brain structures. Nevertheless, no meta-analyses are possible and extrapolation to pilots' performances is hypothetical. Studies in real life or simulated operational situations must be conducted to improve the description of the impact of sleep inertia and kinetics on pilots' performances. Taking rest or sleep time remains the main method for pilots to fight against fatigue and related decreases in performance. We propose proactive strategies to mitigate sleep inertia and improve alertness.Sauvet F, Beauchamps V, Cabon P. Sleep inertia in aviation. Aerosp Med Hum Perform. 2024; 95(4):206-213.

Effects of distance flown on pilot decision making in continued flight into deteriorating weather conditions.

INTRODUCTION: Continuing flight into adverse weather remains a significant problem in general aviation (GA) safety. A variety of experiential, cognitive, and motivational factors have been suggested as explanations. Previous research has shown that adverse weather accidents occur further into planned flights than other types of accident, suggesting that previous investment of time and effort might be a contributing factor. The aim of this study was to experimentally determine the effect of prior commitment on general aviation pilots' decision-making and risk-taking in simulated VFR flights. METHOD: Thirty-six licensed pilots 'flew' two simulated flights designed to simulate an encounter with deteriorating coastal weather and a developing extensive cloud base underneath the aircraft as it crossed a mountain range. After making a decision to continue or discontinue the flight, pilots completed a range of risk perception, risk taking, and situational awareness measures. RESULTS: Visual flight rules were violated in 42% of the flights. Prior commitment, in terms of distance already flown, led to an increased tendency to continue the flight into adverse weather in the coastal 'scud running' scenario. Continuing pilots perceived the risks differently and showed greater risk tolerance than others. These 'bolder' pilots also tended to be more active and better qualified than the others. CONCLUSIONS: There are undoubtedly multiple factors underlying any individual decision to continue or discontinue a flight. The willingness to tolerate a higher level of risk seems to be one such factor. This willingness can increase with time invested in the flight and also seems to be related to individual flight qualifications and experience. PRACTICAL APPLICATIONS: All pilots might benefit from carefully structured simulator sessions designed to safely teach practical risk management strategies with clear and immediate feedback.

SegX-Net: A novel image segmentation approach for contrail detection using deep learning.

Contrails are line-shaped clouds formed in the exhaust of aircraft engines that significantly contribute to global warming. This paper confidently proposes integrating advanced image segmentation techniques to identify and monitor aircraft contrails to address the challenges associated with climate change. We propose the SegX-Net architecture, a highly efficient and lightweight model that combines the DeepLabV3+, upgraded, and ResNet-101 architectures to achieve superior segmentation accuracy. We evaluated the performance of our model on a comprehensive dataset from Google research and rigorously measured its efficacy with metrics such as IoU, F1 score, Sensitivity and Dice Coefficient. Our results demonstrate that our enhancements have significantly improved the efficacy of the SegX-Net model, with an outstanding IoU score of 98.86% and an impressive F1 score of 99.47%. These results unequivocally demonstrate the potential of image segmentation methods to effectively address and mitigate the impact of air conflict on global warming. Using our proposed SegX-Net architecture, stakeholders in the aviation industry can confidently monitor and mitigate the impact of aircraft shrinkage on the environment, significantly contributing to the global fight against climate change.

An HPLC-ESI-QTOF method to analyze polar heteroatomic species in aviation turbine fuel via hydrophilic interaction chromatography.

Aviation turbine fuel is a complex mixture of thousands of compounds. An analytical method using hydrophilic interaction liquid chromatography (HILIC) coupled with electrospray ionization and quadrupole time-of-flight mass spectrometry (ESI-QTOF) was developed for the identification of heteroatomic, polar compounds in aviation turbine fuel. Although compounds containing oxygen, nitrogen, and sulfur functional groups are each found at low levels (<0.1 % by mass) in fuels, their presence can generate significant effects on fuel properties. The HILIC-ESI-QTOF method is a combined separation and detection technique that possesses many advantages including a fast and simple sample preparation-requiring no extraction step therefore ensuring no loss of compounds of interest-and the ability to acquire high-fidelity compound data for chemometric analysis of heteroatomic species in aviation turbine fuel. In the development of the method, it was found that the chromatographic conditions and nature of the injection sample had a significant effect on separation efficiency and repeatability. For a sample dataset optimized using a singular aviation turbine fuel, retention time shift was able to be reduced from 0.4 min to 2.0 % relative standard deviation (RSD) to approximately 0.1 min with RSD of 0.4 % using the newly developed method. In addition, a high number of untargeted molecular features (944) and targeted amines (121) were able to be identified when utilizing optimal method conditions. The specific benefits and limitations of utilizing HILIC techniques with HPLC-ESI-QTOF are also discussed herein. This new method is currently being expanded to include analysis of all heteroatoms and is being applied to real fuel sets. The results of these studies are forthcoming.

A chimp algorithm based on the foraging strategy of manta rays and its application.

To address the issue of poor performance in the chimp optimization (ChOA) algorithm, a new algorithm called the manta ray-based chimpa optimization algorithm (MChOA) was developed. Introducing the Latin hypercube method to construct the initial population so that the individuals of the initial population are evenly distributed in the solution space, increasing the diversity of the initial population. Introducing nonlinear convergence factors based on positive cut functions to changing the convergence of algorithms, the early survey capabilities and later development capabilities of the algorithm are balanced. The manta ray foraging strategy is introduced at the position update to make up for the defect that the algorithm is prone to local optimization, which effectively improves the optimization performance of the algorithm. To evaluate the performance of the proposed algorithm, 27 well-known test reference functions were selected for experimentation, which showed significant advantages compared to other algorithms. Finally, in order to further verify the algorithm's applicability in actual production processes, it was applied to solve scheduling problems in three flexible workshop scenarios and an aviation engine job shop scheduling in an enterprise. This confirmed its efficacy in addressing complex real-world problems.

High blood pressure and aeronautical fitness: experience at the aeromedical expertise center of Rabat.

High blood pressure is a major cardiovascular risk factor closely linked to serious cardiovascular events. A real public health problem affecting more than one in three adults. Aircrew does not escape this pathology, despite very strict medical selection and rigorous and regular medical monitoring by the aircrew doctor during revision visits. We conducted a retrospective study at the medical expertise center for aircrew in Rabat which made it possible to collect 34 hypertensive civilian aircrew for 10 years, from January 2012 to December 2022. The median age at the time of the study was 56.5. The aeronautical specialties practiced by our aircrew population were dominated by class 1. The prevalence of hypertension in Moroccan civilian aircrew: out of 2000 monitored annually at the Aeromedical Expertise Center for 10 years, 34 cases were collected, i.e.: 1.7%. The average age of discovery was 49 years and in 23 cases the diagnosis was established by systematic screening during periodic fitness visits. More than 24 aircrews had no family history of hypertension. On the therapeutic level, lifestyle and dietary measures were systematically prescribed in all our aircrew, 18 patients were put on monotherapy, 11 on dual therapy, and 2 on triple therapy. Compared to fitness decisions, they were variable according to the grade of hypertension, the control of complications, and the aeronautical function. The discovery of hypertension in aircrew can jeopardize aviation safety with the risk of subtle or sudden incapacity in flight through neurological or cardiovascular complications, which could impact the fitness decision. However, advances in medicine and the management of hypertension made in recent years have prompted the medical and aeronautical authorities to revise the standards of aptitude.

The Untapped Potential of Narrative as a Tool in Aviation Mental Health and Certification.

INTRODUCTION: Work-related stress is common in pilots, with broad implications, including the potential development of mental health symptoms and sometimes even psychiatric disease. This commentary argues for the use of narrative as a tool to promote preventive health behaviors in pilots and combat misinformation about aeromedical certification related to mental health.Hoffman WR, McNeil M, Tvaryanas A. The untapped potential of narrative as a tool in aviation mental health and certification. Aerosp Med Hum Perform. 2024; 95(3):165-166.

Safety and Effectiveness Assessment of Ultraviolet-C Disinfection in Aircraft Cabins.

INTRODUCTION: Aircraft cabins, susceptible to disease transmission, require effective strategies to minimize the spread of airborne diseases. This paper reviews the James Reason Swiss Cheese Theory in mitigating these risks, as implemented by the International Civil Aviation Organization during the COVID-19 pandemic. It also evaluates the use of airborne ultraviolet-C (UV-C) light as an additional protective measure.METHODS: Our approach involved a thorough literature review by experts and a detailed risk-vs.-benefit analysis. The review covered existing research to understand the scientific foundation, while the analysis used established techniques to assess the impact of influenza and COVID-19 in terms of infections, deaths, and economic costs.RESULTS: Integrating UV-C light in aircraft cabins, when applied with appropriate scientific understanding and engineering safeguards, has the potential to reduce in-flight disease transmission. This additional mitigation strategy can work synergistically with existing measures.DISCUSSION: The research and risk-vs.-benefit analysis present strong evidence for the safety and effectiveness of continuous UV-C disinfection in aircraft cabins. It suggests that UV-C light, maintained below exposure limits, can be a valuable addition to existing measures against disease transmission during flights.Belland K, Garcia D, DeJohn C, Allen GR, Mills WD, Glaudel SP. Safety and effectiveness assessment of ultraviolet-C disinfection in aircraft cabins. Aerosp Med Hum Perform. 2024; 95(3):147-157.

Exploring the measurement of psychological resilience in Chinese civil aviation pilots based on generalizability theory and item response theory.

Understanding and accurately measuring resilience among Chinese civil aviation pilots is imperative, especially concerning the psychological impact of distressing events on their well-being and aviation safety. Despite the necessity, a validated and tailored measurement tool specific to this demographic is absent. Addressing this gap, this study built on the widely used CD-RISC-25 to analyze and modify its applicability to Chinese civil aviation pilots. Utilizing CD-RISC-25 survey data from 231 Chinese pilots, correlational and differential analyses identified items 3 and 20 as incongruent with this population's resilience profile. Subsequently, factor analysis derived a distinct two-factor resilience psychological framework labeled "Decisiveness" and "Adaptability", which diverged from the structure found in American female pilots and the broader Chinese populace. Additionally, to further accurately identify the measurement characteristics of this 2-factor measurement model, this study introduced Generalized Theory and Item Response Theory, two modern measurement analysis theories, to comprehensively analyze the overall reliability of the measurement and issues with individual items. Results showed that the 2-factor model exhibited high reliability, with generalizability coefficient reaching 0.89503 and dependability coefficient reaching 0.88496, indicating the 2-factor measurement questionnaire can be effectively utilized for relative and absolute comparison of Chinese civil aviation pilot resilience. However, items in Factor 2 provided less information and have larger room for optimization than those in Factor 1, implying item option redesign may be beneficial. Consequently, this study culminates in the creation of a more accurate and reliable two-factor psychological resilience measurement tool tailored for Chinese civil aviation pilots, while exploring directions for optimization. By facilitating early identification of individuals with lower resilience and enabling the evaluation of intervention efficacy, this tool aims to positively impact pilot psychological health and aviation safety in the context of grief and trauma following distressing events.

Longitudinal Changes in the Body Mass Index of British Army Pilots.

INTRODUCTION: Aircraft are manufactured according to design parameters that must account for the size and physical characteristics of the pilot. While cockpit dimensions, seats, restraints, and related components do not change substantially over the airframe lifecycle, it is conceivable that the occupant may, even if initially well-suited. This investigation focused on longitudinal body mass index (BMI) changes within a cohort of British Army Air Corps pilots.METHODS: The study was a retrospective examination of electronic medical record data to assess longitudinal change within a representative cohort of Army pilots. Voluntary subjects were assigned unique subject numbers matched with individual electronic medical record data. Subject's age, service length, height, weight, and BMI were extracted from routine historical aviation medical exams.RESULTS: Among 106 British Army Air Corps pilots, the mean age was 35.3 yr (SD = 7.4) with average length of service as a pilot of 9.0 yr (SD = 5.2). Within the observed cohort, the mean change in individual weight over time was an increase of 4.6 kg (SD = 7.3). Height remained relatively stable with a mean increase of 0.6 cm (SD = 1.9). Given the increase in weight, BMI was noted to increase longitudinally with a mean of 1.3 kg · m-2 (SD = 2.4).DISCUSSION: British Army pilots experience increases in BMI over time much like the general population. Results of this study serve to inform future policy related to the body composition of aviation applicants, the retention of previously qualified pilots, and the safety concerns of crashworthiness design specifications.Porter WD, Wilde GD, Jeffery NP, Walters PL, Eke AJ, Bushby AJR, Adams MS, Gaydos SJ. Longitudinal changes in the body mass index of British Army pilots. Aerosp Med Hum Perform. 2024; 95(2):118-122.

Health-Related Factors Among Pilots in Aviation Accidents.

INTRODUCTION: Health-related factors can impact aviation safety. This study investigated the published, historical aviation accidents that have been investigated by the U.S. National Transportation Safety Board (NTSB) to understand medical conditions and medication use that have been determined to be causal to mishaps.METHODS: A two-part approach was adopted for this study: 1) a scoping review was conducted to provide an overview of the current medical literature addressing medical factors and flight safety; and 2) a comprehensive review of aviation accident reports from the NTSB database from January 2013 to October 2022.RESULTS: The literature review demonstrated that psychiatric, cardiovascular, and neurological medications were the major categories of medications reported in fatal aircraft accidents. Age was not found to be a risk factor. Review of the NTSB database demonstrated that, among 15,654 mishaps, medical factors were associated in 703 (4.5%) accidents. NTSB data showed that cardiovascular (1.3%), psychiatric (0.23%), and endocrine diseases (0.17%) were the most commonly reported diseases among pilots. In accident reports, cardiovascular medications (1.49%), sedating antihistamines (0.91%), and alcohol (0.70%) were the most commonly used medications at the time of the accidents.DISCUSSION: Health-related factors were a small yet likely underestimated proportion of the factors associated with accidents. Cardiovascular diseases and treatment were the most important factors. It is important to continue to investigate the association between health-related factors and the commission of mishaps.Zhu Y, Wolf ME, Alsibai RA, Abbas AS, Alsawaf Y, Saadi S, Farah MH, Wang Z, Murad MH. Health-related factors among pilots in aviation accidents. Aerosp Med Hum Perform. 2024; 95(2):79-83.

The impact of Chinese airport infrastructure on airline pollutant emissions: A hybrid stochastic-neural network approach based on utility functions.

With China being the world's largest emitter of greenhouse gases and its aviation sector burgeoning, the environmental performance of Chinese airlines has global significance. Amidst rising demands for eco-friendly practices from both customers and regulators, the interplay between airport infrastructure and environmental performance becomes pivotal. This research offers an innovative methodology to gauge the environmental performance of Chinese airlines, emphasizing the distance traveled between airports using weighted additive utility functions. Leveraging neural networks, the study investigates the impact of various airport infrastructural characteristics on environmental performance. Noteworthy findings indicate that ground control measures, automatic information services at origin airports, surface concrete on runways at both ends, and a centerline lighting system in destination airports positively influence environmental performance. In contrast, longer and wider runways at origin airports, increased distances to control towers, and asphalt runways at destination airports adversely affect it. These insights not only underscore the importance of strategic infrastructure enhancements for reducing carbon footprints but also hold profound policy implications. As global climate change remains at the forefront, fostering sustainable airport infrastructure in China can significantly contribute to worldwide mitigation efforts.

Life cycle assessment of novel thermochemical - biochemical biomass-to-liquid pathways for sustainable aviation and maritime fuel production.

This paper aims to carry out an integrated Life Cycle Assessment (LCA) to evaluate the environmental performance of a novel thermochemical-biochemical biomass-to-liquid pathway for sustainable aviation and maritime biofuel production. Five scenarios are defined, consideringdifferent types of biomass feedstock and biorefinery locations, in different geographically dispersed European countries. The results indicate that the replacement of conventional aviation and maritime fuels with sustainable biofuels could reduce Greenhouse Gases (GHG) by 60-86%, based on feedstock type. When the renewable share in the electricity mix reaches 100% (in 2050), the GHG emissions will experience a great decrease (26% - 68%), compared to 2022 levels. The non-renewable energy consumption will also decrease (by 56% - 83%), with results strongly affected by the electricity mix of the European country considered. This study demonstrates that the deployment of biomass-to-jet/marine fuel pathways could favor the industrial adoption of circular economy strategies for transport biofuels production.

Personal Hypoxia Symptoms Vary Widely Within Individuals.

INTRODUCTION: Exposure to high ambient altitudes above 10,000 ft (3048 m) over sea level during aviation can present the risk of hypobaric hypoxia. Hypoxia can impair sensory and cognitive functions, degrading performance and leading to mishaps. Military aircrew undergo regular hypoxia familiarization training to recognize their symptoms and understand the consequences of hypoxia. However, over the years, aviators have come to believe that individuals have a "personal hypoxia signature." The idea is that intraindividual variability in symptom experience during repeated exposure is low. In other words, individuals will experience the same symptoms during hypoxia from day to day, year to year.METHODS: We critically reviewed the existing literature on this hypothesis. Most studies that claim to support the notion of a signature only examine group-level data, which do not inform individual-level consistency. Other studies use inappropriate statistical methods, while still others do not control for accuracy of recall over the period of years. To combat these shortcomings, we present a dataset of 91 individuals who completed nearly identical mask-off, normobaric hypoxia exposures days apart.RESULTS: We found that for every symptom on the Hypoxia Symptom Questionnaire, at least half of the subjects reported the symptom inconsistently across repeated exposure. This means that, at best, 50% of subjects did not report the same symptom across exposures.DISCUSSION: These data provide compelling evidence against the existence of hypoxia signatures. We urge that hypoxia familiarization training incorporate these findings and encourage individuals to expect a wide range of hypoxia symptoms upon repeated exposure.Cox BD, McHail DG, Blacker KJ. Personal hypoxia symptoms vary widely within individuals. Aerosp Med Hum Perform. 2024; 95(1):54-58.

Sugar-Sweetened Beverage Consumption and Implications for Aviation Preflight Indoctrination Students.

BACKGROUND: Research has shown that excessive sugar-sweetened beverage (SSB) consumption has been associated with being overweight and obese and the military is not immune to this disorder. Being overweight/obese is one of the characteristics that comprise a condition known as Metabolic Syndrome (MetS). The global prevalence of MetS in the military population is estimated to be 21%, which varies depending upon the armed forces type and specialty. The purpose of this study is to identify the subset of the aviation population that may develop MetS at some future point and to put forth suggestions on how best to combat this and maintain operational readiness.METHODS: Data were collected by means of an anonymous 44-item survey administered and completed by 302 students enrolled in Aviation Preflight Indoctrination at the Naval Air Station Base in Pensacola, FL.RESULTS: Results indicated that 70.86% of students reported SSB consumption, with 95.3% preferring caffeinated to decaffeinated SSBs. 11.7% of personnel met the "at risk criteria" of consuming SSBs four times per week or greater (four 12-oz cans or more per week).DISCUSSION: Findings from this study indicate that approximately 11.7% of aviation pilots or flight officers are "at risk" of developing MetS. Given that it takes up to 4 yr to train a new fighter pilot, this could become a significant readiness issue on par with the impact seen with pilots leaving the services through natural attrition.Sather TE. Sugar-sweetened beverage consumption and implications for aviation preflight indoctrination students. Aerosp Med Hum Perform. 2024; 95(1):25-28.