Identifying activity level related movement features of children with ASD based on ADOS videos.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that affects about 2% of children. Due to the shortage of clinicians, there is an urgent demand for a convenient and effective tool based on regular videos to assess the symptom. Computer-aided technologies have become widely used in clinical diagnosis, simplifying the diagnosis process while saving time and standardizing the procedure. In this study, we proposed a computer vision-based motion trajectory detection approach assisted with machine learning techniques, facilitating an objective and effective way to extract participants' movement features (MFs) to identify and evaluate children's activity levels that correspond to clinicians' professional ratings. The designed technique includes two key parts: (1) Extracting MFs of participants' different body key points in various activities segmented from autism diagnostic observation schedule (ADOS) videos, and (2) Identifying the most relevant MFs through established correlations with existing data sets of participants' activity level scores evaluated by clinicians. The research investigated two types of MFs, i.e., pixel distance (PD) and instantaneous pixel velocity (IPV), three participants' body key points, i.e., neck, right wrist, and middle hip, and five activities, including Table-play, Birthday-party, Joint-attention, Balloon-play, and Bubble-play segmented from ADOS videos. Among different combinations, the high correlations with the activity level scores evaluated by the clinicians (greater than 0.6 with p < 0.001) were found in Table-play activity for both the PD-based MFs of all three studied key points and the IPV-based MFs of the right wrist key point. These MFs were identified as the most relevant ones that could be utilized as an auxiliary means for automating the evaluation of activity levels in the ASD assessment.

Changes in vital signs, ventilation mode, and catecholamine use during intensive care aeromedical evacuation flights.

Introduction: Especially after (natural) disasters, local health systems are also destroyed or their ability to work is massively restricted. The transport of injured patients is therefore often necessary for further care. Numerous nations keep fixed-wing aircraft with intensive-care capabilities available for secondary transport, but little data on the transport is available to date. Methods: An analysis of all flights with the German Air Force's intensive care fixed-wing-aircraft carried out in the context of humanitarian aid missions since 2002 with a focus on intubated patients was done. Results: A total of 38 patients were transported. Two patients had to be intubated on or during transport. There were significant changes in the necessary positive end-expiratory pressure (PEEP) and the fraction of inspired oxygen. Circulatory parameters did not change. Discussion: Overall, there are no clinically relevant deteriorations due to secondary transport with corresponding air transfers. Due to the hypobaric hypoxic conditions on board of all aircrafts, intubation in clinically borderline patients should be performed electively on the ground before flight.

[Management of helicopter medical transport in 36 patients with critical cardiac disease].

OBJECTIVE: To summarize the management experience of helicopter medical transport in patients with critical heart disease, so as to provide reference for transport of patients with critical heart disease under the background of major natural disasters. METHODS: The clinical and transport data of 36 critically ill cardiac patients in Fuwai Central China Cardiovascular Hospital from 16:30 on July 21 to 19:30 on July 22, 2021 due to historically rare heavy rainstorms were collected. All 36 critically ill cardiac patients were transported by helicopter. The safe transportation was implemented under the measures of quickly forming a transport leadership and coordination group, clarifying responsibilities and division of labor, doing a good job in the pretreatment of the patient's condition, pipeline assessment and mechanical circulation support (MCS) equipment, simulating and practicing the transfer process, improving the safety of the transfer implementation process, and effectively handing over with the target hospital. The gender, age, disease type, MCS, transport and outcome of patients were collected. RESULTS: Thirty-six patients with cardiac critical illness were from adult extracardiac intensive care unit (ICU), adult cardiac care unit (CCU), children's CCU, comprehensive ICU and department of neurology. There were 24 males and 12 females; age (50.93±20.86) years old. There were 12 patients using respirator, 7 patients needing MCS, 2 of whom needed both extracorporeal membrane oxygenation (ECMO) and intra-aortic balloon pump (IABP), and 7 patients with post-cardiac surgery. The total distance of transportation of 36 patients was 1 638.4 km, the transit time was 10.5 hours, one way flight time of helicopter was about 8 minutes, and the average transport time per patient was about 17.5 minutes. The vital signs of 36 patients during transport were basically stable, without complications, and all of them reached the target hospital safely. CONCLUSIONS: Under the seamless connection of the rapid establishment of the transfer leadership coordination group, assessment of the patient's condition and pretreatment, the simulation of the transfer process, and the effective handover with the receiving hospital, the use of helicopter for medical transport for critically ill heart patients is feasible and safe, which can buy valuable time for saving patients' lives and further treatment.

Multiobjective Gate Assignment Model Considering Carbon Emissions.

It has been a main concern for governments to reduce the carbon emission of the aviation industry. The paper proposes a multiobjective gate assignment model that considers the carbon emission at the airport surface to facilitate environmental-friendly airport construction. Three objectives are considered in the model to reduce carbon emissions, including the proportion of flights assigned to the contact gate, aircraft taxiing fuel consumption, and gate assignment robustness. In order to achieve better performance on all objectives, a Non-dominated Sorting Genetic Algorithm-II (NSGA-II) is used to obtain the optimal results. The operation data from a domestic airport is deployed to validate the model. The optimal results of the gate assignment model are compared with the original scheme. It indicates that the proposed model can effectively reduce carbon emissions. The study can provide a strategy for gate assignment to reduce carbon emissions and improve the management of the airport.

The effect of COVID-19 on self-reported safety incidents in aviation: An examination of the heterogeneous effects using causal machine learning.

INTRODUCTION: Disruptions to aviation operations occur daily on a micro-level with negligible impacts beyond the inconvenience of rebooking and changing aircrew schedules. The unprecedented disruption in global aviation due to COVID-19 highlighted a need to evaluate emergent safety issues rapidly. METHOD: This paper uses causal machine learning to examine the heterogeneous effects of COVID-19 on reported aircraft incursions/excursions. The analysis utilized self report data from NASA Aviation Safety Reporting System collected from 2018 to 2020. The report attributes include self identified group characteristics and expert categorization of factors and outcomes. The analysis identified attributes and subgroup characteristics that were most sensitive to COVID-19 in inducing incursions/excursions. The method included the generalized random forest and difference-in-difference techniques to explore causal effects. RESULTS: The analysis indicates first officers are more prone to experiencing incursion/excursion events during the pandemic. In addition, events categorized with the human factors confusion, distraction, and the causal factor fatigue increased incursion/excursion events. PRACTICAL APPLICATIONS: Understanding the attributes associated with the likelihood of incursion/excursion events provides policymakers and aviation organizations insights to improve prevention mechanisms for future pandemics or extended periods of reduced aviation operations.

Use of flight tracking data to inform safety deficiencies for general aviation cross-country operations in challenging flying environments.

BACKGROUND: Air carriers, but not general aviation, have long employed in-flight data to identify risks/implement corrective measures for improved safety. Herein, using in-flight data, aircraft (in non-instrument-rated private pilots (PPLs) ownership) operations in two potentially hazardous environments (mountains, degraded visibility) were researched for safety practice deficiencies. Four questions were posed, the first two related to mountainous terrain operations: were aircraft (a) flown with hazardous ridge-level winds, (b) within gliding distance of level terrain? Regarding degraded visibility, did aviators (c) depart with low cloud ceilings (≤3,000 ft.), (d) fly at night away from urban lighting? METHODS: The study cohort comprised: (a) single engine aircraft in sole PPL proprietorship (b) registered in Automatic Dependent Surveillance-Broadcast (ADS-B-Out) equipage-required locations prone to low cloud ceilings in three mountainous states. ADS-B-Out data for cross-country flights (>200 nm) were collected. RESULTS: 250 flights (50 airplanes) were tracked (spring/summer 2021). For aircraft transiting areas subject to mountain winds influences, 65% completed one/multiple flights with potentially hazardous ridge-level winds. Two thirds of airplanes traversing mountainous topography would have, for at least one flight, been unable to glide to level terrain with a powerplant failure. Encouragingly, flight departures for 82% of the aircraft were with >3,000 ft. cloud ceilings. Likewise, flights for >86% of the study cohort were undertaken during daylight. Employing a risk scale, operations for 68% of the study cohort did not exceed low-risk (i.e., ≤1 unsafe practice) and high-risk flight(s) (three concurrent unsafe practices) were rare (4% of airplanes). In log-linear analysis, no interactions were evident between the four unsafe practices (p = 0.602). DISCUSSION: Hazardous winds and inadequate engine failure planning were identified as safety deficiencies for general aviation mountain operations. PRACTICAL APPLICATION: This study advocates for the expanded use of ADS-B-Out in-flight data to inform safety deficiencies/implement corrective measures toward improving general aviation safety.

Bakri Balloon for Treatment of Postpartum Hemorrhage: A Real-World 2016-2020 Study in 279 Women from a Single Center.

BACKGROUND Postpartum hemorrhage (PPH) may be primary or secondary and is defined as the loss of 500 ml or more of blood within the first 24 h after birth. The Bakri balloon tamponade (BBT) is an intrauterine device used as an adjunctive treatment for refractory PPH. The aim of this study was to present the real-world experience from a single center on the effectiveness of the BBT for the treatment of PPH. MATERIAL AND METHODS This cohort study of 279 women was conducted in a real-world setting. Patients' characteristics and clinical outcomes between the BBT Success group and BBT Failure group were analyzed by t test or chi-square test. The primary outcome was the success rate of BBT. The secondary outcomes were the perinatal outcomes. RESULTS The success rate of BBT was 88.89% (248/279). A blood transfusion rate of 65.95% (184/279) was observed. After using the BBT, significant differences were observed in intervention (P<0.001), blood loss (P<0.001), indwelling time of BBT (P<0.001), and blood transfusion (P<0.001) between the Success group and Failure group. The Success group showed greater range of descent in blood loss (991.56.15±13.65 mL in Success group vs 816.23±7.57 mL in Failure group). Of the 31 women with BBT failure, 87.10% (27/31) received uterine artery embolization (UAE), 96.77% (30/31) received blood transfusion, and none required a hysterectomy. CONCLUSIONS The findings from this study from a single center in China supported those from previous studies showing that the BBT was an effective treatment to control PPH.

Typical Cockpit Ergonomics Influence on Cervical Motor Control in Healthy Young Male Adults.

INTRODUCTION: Neck pain and injury are common problems in military high-performance aircraft and helicopter aircrews. A contributing factor may be the reclined sitting position in cockpits. This study aimed to determine the effect of typical cockpit ergonomics on cervical proprioception, assessed by using the cervical joint position error (cJPE).METHODS: A total of 49 healthy male military employees (mean age 19.9 ± 2.2 yr) were examined. Measurements of the cJPE were obtained in the flexion, extension, and rotation directions in an upright and in a 30°-reclined sitting position. Each condition comprised three trials, with an additional 3-kg head load to mimic real world working conditions.RESULTS: A smaller cJPE was noted in the 30°-reclined sitting position (mean cJPE = 3.9 cm) than in the upright sitting position (mean cJPE = 4.6 cm) in the flexion direction. The cJPE decreased significantly in all movement directions across the three trials; for example, in the flexion direction in the 30°-reclined sitting position: Trial 1/2/3 mean cJPE = 5.0/3.8/3.1 cm.CONCLUSION: It seems that a reclined seating position has a positive influence on cJPE. However, the result is weak. In both sitting positions and all three directions, the first tests of the cJPE showed the highest values. Already after one or two further measurement runs, a significantly reduced cJPE was observed. This rapid improvement might indicate that an exercise similar to the cJPE test may improve the pilots' cervical proprioception and possibly reduce the risk of injury or pain.Heggli U, Swanenburg J, Hofstetter L, Häusler M, Schweinhardt P, Bron D. Typical cockpit ergonomics influence on cervical motor control in healthy young male adults. Aerosp Med Hum Perform. 2023; 94(3):107-112.

BASE Jumping in the Lauterbrunnen Valley: A Retrospective Cohort Study from 2007 to 2016.

BACKGROUND: BASE jumping, and especially BASE jumping with the help of wingsuits, is considered one of the most dangerous airborne sports. The valley of Lauterbrunnen in Switzerland has become infamous for the large number of BASE jumps and the high rate of accidents and fatalities. The aim of this study was to evaluate the morbidity and mortality of BASE jumping, to determine the severity of injuries and injury patterns of BASE jumping accidents and to compare preclinical assessment with clinical diagnoses to detect under- or overtriage. METHODS: This retrospective, descriptive cohort study covers a period of 10 years (2007-2016). The evaluation covered all BASE jumping incidents in the valley of Lauterbrunnen that required either a helicopter mission by the local HEMS (Helicopter Emergency Medical Service) company of Lauterbrunnen, Air Glaciers, or medical care in the regional hospital, the level I trauma centre or the medical practice of the local general practitioner. Besides demographic data, experience in BASE jumping and skydiving as well as BASE jumping technique(s) and details about the rescue missions were collected. The medical data focused on the severity of injuries, as expressed by the National Advisory Committee of Aeronautics (NACA) score in the prehospital assessment as well as the Abbreviated Injury Scale (AIS) and Injury Severity Score (ISS) retrieved from the clinical records in the hospital or medical practice setting. RESULTS: The patients were predominantly young, experienced male BASE jumpers. Morbidity (injury risk) ranged from 0.05% to 0.2%, and fatality risk from 0.02% to 0.08%. Undertriage was low, with only two cases. Overtriage was significant, with 73.2% of all NACA 4-6 cases not qualifying for major trauma. CONCLUSIONS: BASE jumping remains a high-risk sport and is associated with significant rates of injuries and fatalities. Comparison with previous studies indicated that the injury rate may have decreased, but the fatality rate had not. In this known BASE jumping environment, prehospital assessment appears to be good, as we found a low undertriage rate. The high overtriage rate might be an expression of physicians' awareness of high-velocity trauma mechanisms and possible deceleration injuries.

The effect of flight phase on electrodermal activity and gaze behavior: A simulator study.

Current advances in airplane cockpit design and layout are often driven by a need to improve the pilot's awareness of the aircraft's state. This involves an improvement in the flow of information from aircraft to pilot. However, providing the aircraft with information on the pilot's state remains an open challenge. This work takes a first step towards determining the pilot's state based on biosensor data. We conducted a simulator study to record participants' electrodermal activity and gaze behavior, indicating pilot state changes during three distinct flight phases in an instrument failure scenario. The results show a significant difference in these psychophysiological measures between a phase of regular flight, the incident phase, and a phase with an additional troubleshooting task after the failure. The differences in the observed measures suggest great potential for a pilot-aware cockpit that can provide assistance based on the sensed pilot state.

Mitotic outcomes and errors in fibrous environments.

During mitosis, cells round up and utilize the interphase adhesion sites within the fibrous extracellular matrix (ECM) as guidance cues to orient the mitotic spindles. Here, using suspended ECM-mimicking nanofiber networks, we explore mitotic outcomes and error distribution for various interphase cell shapes. Elongated cells attached to single fibers through two focal adhesion clusters (FACs) at their extremities result in perfect spherical mitotic cell bodies that undergo significant 3-dimensional (3D) displacement while being held by retraction fibers (RFs). Increasing the number of parallel fibers increases FACs and retraction fiber-driven stability, leading to reduced 3D cell body movement, metaphase plate rotations, increased interkinetochore distances, and significantly faster division times. Interestingly, interphase kite shapes on a crosshatch pattern of four fibers undergo mitosis resembling single-fiber outcomes due to rounded bodies being primarily held in position by RFs from two perpendicular suspended fibers. We develop a cortex-astral microtubule analytical model to capture the retraction fiber dependence of the metaphase plate rotations. We observe that reduced orientational stability, on single fibers, results in increased monopolar mitotic defects, while multipolar defects become dominant as the number of adhered fibers increases. We use a stochastic Monte Carlo simulation of centrosome, chromosome, and membrane interactions to explain the relationship between the observed propensity of monopolar and multipolar defects and the geometry of RFs. Overall, we establish that while bipolar mitosis is robust in fibrous environments, the nature of division errors in fibrous microenvironments is governed by interphase cell shapes and adhesion geometries.

Does 2x2 airplane passenger contact tracing for infectious respiratory pathogens work? A systematic review of the evidence.

We critically appraised the literature regarding in-flight transmission of a range of respiratory infections to provide an evidence base for public health policies for contact tracing passengers, given the limited pathogen-specific data for SARS-CoV-2 currently available. Using PubMed, Web of Science, and other databases including preprints, we systematically reviewed evidence of in-flight transmission of infectious respiratory illnesses. A meta-analysis was conducted where total numbers of persons on board a specific flight was known, to calculate a pooled Attack Rate (AR) for a range of pathogens. The quality of the evidence provided was assessed using a bias assessment tool developed for in-flight transmission investigations of influenza which was modelled on the PRISMA statement and the Newcastle-Ottawa scale. We identified 103 publications detailing 165 flight investigations. Overall, 43.7% (72/165) of investigations provided evidence for in-flight transmission. H1N1 influenza A virus had the highest reported pooled attack rate per 100 persons (AR = 1.17), followed by SARS-CoV-2 (AR = 0.54) and SARS-CoV (AR = 0.32), Mycobacterium tuberculosis (TB, AR = 0.25), and measles virus (AR = 0.09). There was high heterogeneity in estimates between studies, except for TB. Of the 72 investigations that provided evidence for in-flight transmission, 27 investigations were assessed as having a high level of evidence, 23 as medium, and 22 as low. One third of the investigations that reported on proximity of cases showed transmission occurring beyond the 2x2 seating area. We suggest that for emerging pathogens, in the absence of pathogen-specific evidence, the 2x2 system should not be used for contact tracing. Instead, alternate contact tracing protocols and close contact definitions for enclosed areas, such as the same cabin on an aircraft or other forms of transport, should be considered as part of a whole of journey approach.

Cabin Pressure Altitude Effect on Acceleration Atelectasis After Agile Flight Breathing 60% Oxygen.

INTRODUCTION: A flight trial was conducted to determine whether breathing 60% oxygen during high performance flight maneuvers using contemporary pilot flight equipment induces atelectasis and to explore whether cabin altitude had any influence on the extent of atelectasis identified.METHODS: On 2 separate days, 14 male aircrew flew as passengers at High [14,500-18,000 ft (4420-5486 m)] and Low [4000-6000 ft (1219-1829 m)] cabin pressure altitude in a Hawk T Mk1 aircraft breathing 60% oxygen. Sorties comprised 16 maneuvers at +5 Gz, each sustained for 30 s. Lung volumes (spirometry), basal lung volume (electrical impedance tomography, EIT), and peripheral oxygen saturation during transition from hyperoxia to hypoxia (pulmonary shunt fraction) were measured in the cockpit immediately before (Pre) and after (Post) flight.RESULTS: Forced inspiratory vital capacity (FIVC) was significantly lower Postflight after High (-0.24 L) and Low (-0.38 L) sorties, but recovered to Preflight values by the fourth repeat (FIVC4). EIT-derived measures of FIVC decreased after High (-3.3%) and Low (-4.4%) sorties but did not recover to baseline by FIVC4. FIVC reductions were attributable to decreased inspiratory capacity. Spo2 was lower Postflight than Preflight in High and Low sorties.DISCUSSION: Breathing 60% oxygen during flight results in a 3.8-4.9% reduction in lung volume associated with a small decrease in blood oxygenation and an estimated pulmonary shunt of up to 5.7%. EIT measures suggest persisting airway closure despite repeated FIVC maneuvers. There was no meaningful influence of cabin pressure altitude. The operational consequence of the observed changes is likely to be small.Tank H, Kennedy G, Pollock R, Hodkinson P, Sheppard-Hickey R-A, Woolford J, Green NDC, Stevenson A. Cabin pressure altitude effect on acceleration atelectasis after agile flight breathing 60% oxygen. Aerosp Med Hum Perform. 2023; 94(1):3-10.

Test Pilot and Airline Pilot Differences in Facing Unexpected Events.

BACKGROUND: Unexpected events in flight might decrease the transparency of the flying process and weaken the pilot's perception of the current state, or even erode manipulating skills. However, during the flight test of a new or modified aircraft, to verify the boundaries of aircraft aerodynamic performance and handling stability, unexpected events may be encountered that need to be handled by the test pilot. Therefore, studying the differences between test pilots and airline pilots could help improve flight safety.METHODS: Two kinds of physiological parameters, eye blink rate and average fixation duration and task-related performance of test pilots and airline pilots, were analyzed in three abnormal scenarios. A total of 16 pilots participated. The study was carried out in an A320 flight simulator.RESULTS: The differences were significant for both test pilots and airline pilots in eye blink rate and average fixation duration. Furthermore, the reaction time of test pilots (Mean = 23.38 s) was significantly shorter than airline pilots (Mean = 42.63 s) in Unreliable Airspeed condition, and the pitch angle deviations between them were significant in both Wind Shear and Unreliable Airspeed condition.DISCUSSION: The uncertainty of environmental change could create more severe pressure and mental workload influence than actual system failure. For airline pilots, compared with test pilots, the importance of practicing manual flight should still be emphasized. Improving reactions to unexpected ambient conditions and unannounced fault status could also contribute to flight safety.Zheng Y, Lu Y, Jie Y, Zhao Z, Fu S. Test pilot and airline pilot differences in facing unexpected events. Aerosp Med Hum Perform. 2023; 94(1):18-24.

A Regional Approach to Aviation Accident Analysis in Hawaii.

BACKGROUND: The geographical circumstances, such as mountains and ocean, and specific aviation operations, especially sightseeing, make the state of Hawaii stand out in aviation. These conditions support a regional approach to aviation accident analysis.METHODS:Accident reports of aviation accidents collected from the online National Transportation Safety Board database were used to study a 10-yr time period between 2008 and 2017.RESULTS: There was a significantly higher proportion of fatal accidents during night, dawn, and dusk (6 out of 13) than during daytime (13 out of 74). In addition, a significantly higher proportion of accidents occurred in diminished light conditions among fixed wing airplanes (11 out of 48) as opposed to other aircraft (2 out of 39), and among twin-engine aircraft (6 out of 12) as opposed to single-engine aircraft (7 out of 74). Out of seven weight-shift control aviation accidents, four were reported to be fatal; the latter all took place during instruction.DISCUSSION: Light conditions are the main environmental concern in Hawaiian aviation that particularly affect twin-engine fixed wing aircraft and warrant specific attention in advanced training exercises. Helicopter operations have not exhibited a diminished safety record since the 1990s, showing a lasting effect of a previous safety intervention. A relatively high number of fatal weight-shift control aircraft accidents requires further research in other parts of the United States.de Voogt AJ, Brause J. A regional approach to aviation accident analysis in Hawaii. Aerosp Med Hum Perform. 2023; 94(3):131-134.

Methane Venting at Cold Heavy Oil Production with Sand (CHOPS) Facilities Is Significantly Underreported and Led by High-Emitting Wells with Low or Negative Value.

Cold Heavy Oil Production with or without Sand, CHOP(S), facilities produce a significant portion of Canada's conventional oil. Methane venting from single-well CHOPS facilities in Saskatchewan, Canada was measured (i) using Bridger Photonics' airborne Gas Mapping LiDAR (GML) at 962 sites and (ii) on-site using an optical mass flux meter (VentX), ultrasonic flow meter, and QOGI camera at 11 sites. The strong correlation between ground measurements and airborne GML supported subsequent detailed analysis of the aerial data and to our knowledge is the first study to directly test the ability of airplane surveys to accurately reproduce mean emission rates of unsteady sources. Actual methane venting was found to be nearly four times greater than the industry-reported levels used in emission inventories, with ∼80% of all emissions attributed to casing gas venting. Further analysis of site-total emissions revealed potential gaps in regulations, with 14% of sites appearing to exceed regulated limits while accounting for 61% of measured methane emissions. Finally, the concept of marginal wells was adapted to consider the inferred cost of methane emissions under current carbon pricing. Results suggest that almost a third of all methane is emitted from environmentally marginal wells, where the inferred methane cost negates the value of the oil produced. Overall, the present results illustrate the importance of independent monitoring, reporting, and verification (MRV) to ensure accuracy in reporting and regulatory compliance, and to ensure mitigation targets are not foiled by a collection of disproportionately high-emitting sites.

Using machine learning methods and EEG to discriminate aircraft pilot cognitive workload during flight.

Pilots of aircraft face varying degrees of cognitive workload even during normal flight operations. Periods of low cognitive workload may be followed by periods of high cognitive workload and vice versa. During such changing demands, there exists potential for increased error on behalf of the pilots due to periods of boredom or excessive cognitive task demand. To further understand cognitive workload in aviation, the present study involved collection of electroencephalogram (EEG) data from ten (10) collegiate aviation students in a live-flight environment in a single-engine aircraft. Each pilot possessed a Federal Aviation Administration (FAA) commercial pilot certificate and either FAA class I or class II medical certificate. Each pilot flew a standardized flight profile representing an average instrument flight training sequence. For data analysis, we used four main sub-bands of the recorded EEG signals: delta, theta, alpha, and beta. Power spectral density (PSD) and log energy entropy of each sub-band across 20 electrodes were computed and subjected to two feature selection algorithms (recursive feature elimination (RFE) and lasso cross-validation (LassoCV), and a stacking ensemble machine learning algorithm composed of support vector machine, random forest, and logistic regression. Also, hyperparameter optimization and tenfold cross-validation were used to improve the model performance, reliability, and generalization. The feature selection step resulted in 15 features that can be considered an indicator of pilots' cognitive workload states. Then these features were applied to the stacking ensemble algorithm, and the highest results were achieved using the selected features by the RFE algorithm with an accuracy of 91.67% (± 0.11), a precision of 93.89% (± 0.09), recall of 91.67% (± 0.11), F-score of 91.22% (± 0.12), and the mean ROC-AUC of 0.93 (± 0.06). The achieved results indicated that the combination of PSD and log energy entropy, along with well-designed machine learning algorithms, suggest the potential for the use of EEG to discriminate periods of the low, medium, and high workload to augment aircraft system design, including flight automation features to improve aviation safety.

Fatal Air Medical Accidents in the United States (2000-2020).

INTRODUCTION: Currently, many airplanes and helicopters are used as air ambulances to transport high-acuity patients. Unfortunately, civilian air medical transport in the United States has experienced a significant number of serious and fatal accidents. At the moment, additional research is needed to identify what factors affect air medical safety. METHODS: Accident reports from the National Transportation Safety Board (NTSB) were queried. Accident reports were analyzed if the accident occurred from 2000 through 2020, involved a helicopter or airplane on an air medical flight (as identified by the NTSB), and had at least one fatality. The date of the accident, the model of aircraft involved, and NTSB-determined probable causes of the accident were examined. RESULTS: Eighty-seven (87) accidents and 239 fatalities took place from January 2000 through December 2020. Nearly three-fourths (72.4%) of fatalities occurred on helicopters, while just 27.6% occurred on airplanes. Interpreting the NTSB findings, various human factors probably contributed to 87.4% of fatalities. These include pilot disorientation, pilot errors, maintenance errors, impairment, fatigue, or weather misestimation. Nighttime-related factors probably contributed to 38.9% of fatalities, followed by weather-related factors (35.6%), and various mechanical failures (17.2%). CONCLUSION: These data show that the probable causes of fatal air medical accidents are primarily human factors and are, therefore, likely preventable. Developing a safety-first culture with a focus on human factors training has been shown to improve outcomes across a wide range of medical specialties (eg, anesthesia, surgery, and resuscitation). While there have been fewer fatal accidents in recent years, a continued emphasis on various training modalities seems warranted.

Stress of emergency physicians during helicopter operations: impact of patients' diagnoses, severity of diagnoses, and physicians' work experience.

PURPOSE: Emergency physicians are in danger of developing illnesses due to stress in their demanding work environment. Until today, scholars have not identified stressors or resilience factors that qualify to promote the preservation of emergency physicians' well-being. Therefore, potential influencing variables such as patients' diagnoses, the severity of diagnoses, as well as physicians' work experience have to be considered. The present study aims at investigating emergency physicians in the Helicopter Emergency Medical Service (HEMS)' autonomic nervous system activity during emergency operations in one shift with respect to patients' diagnoses, severity of diagnoses, and physicians' work experience. METHODS: Measurement of HRV (employing the parameters RMSSD and LF/HF) for 59 EPs (age: M = 39.69, SD = 6.19) was performed during two complete air-rescue-days, the alarm and landing phase being investigated in particular. Besides patients' diagnoses, the National Advisory Committee for Aeronautics Score (NACA) was included as an indicator for severity. Diagnoses' and NACA's effect on HRV were examined using a linear mixed model. RESULTS: Both HRV parameters indicate a significant decrease of the parasympathetic nervous system as a function of the diagnoses. Furthermore, high NACA scores (≥ V) predicted a significantly lower HRV. In addition, a lower HRV/RMSSD with increasing work experience was observed as well as a positive association between physicians' work experience and sympathetic activation (LF/HF). CONCLUSION: The present study showed that pediatric diagnoses as well as time-critical diagnoses are most stressful and have the highest impact on the physicians' ANS. This knowledge allows the development of specific training to reduce stress.