One-year survival of aneurysmal subarachnoid hemorrhage after airplane transatlantic transfer - a monocenter retrospective study.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) is preferentially treated by prompt endovascular coiling, which is not available in Guadeloupe. Subsequently, patients are transferred to Paris, France mainland, by commercial airplane (6751 km flight) after being managed according to guidelines. This study describes the characteristics, management and outcomes related to these patients. METHODS: Retrospective observational cohort study of 148 patients admitted in intensive care unit for a suspected aSAH and transferred by airplane over a 10-year period (2010-2019). RESULTS: The median [interquartile range] age was 53 [45-64] years and 61% were female. On admission, Glasgow coma scale was 15 [13-15], World Federation of Neurological Surgeons (WFNS) grading scale was 1 [1-3] and Fisher scale was 4 [2-4]. External ventricular drainage and mechanical ventilation were performed prior to the flight respectively in 42% and 47% of patients. One-year mortality was 16% over the study period. By COX logistic regression analysis, acute hydrocephalus (hazard ratio [HR] 2.34, 95% confidence interval [CI] 0.98-5.58) prior to airplane transfer, WFNS grading scale on admission (HR 1.53, 95% CI 1.16-2.02) and age (OR 1.03, 95% 1.00-1.07) were associated with one-year mortality. CONCLUSION: When necessary, transatlantic air transfer of patients with suspected aSAH after management according to local guidelines seems feasible and safe.

Risk of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Transmission Among Air Passengers in China.

BACKGROUND: Modern transportation plays a key role in the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and new variants. However, little is known about the exact transmission risk of the virus on airplanes. METHODS: Using the itinerary and epidemiological data of coronavirus disease 2019 (COVID-19) cases and close contacts on domestic airplanes departing from Wuhan city in China before the lockdown on 23 January 2020, we estimated the upper and lower bounds of overall transmission risk of COVID-19 among travelers. RESULTS: In total, 175 index cases were identified among 5797 passengers on 177 airplanes. The upper and lower attack rates (ARs) of a seat were 0.60% (34/5622, 95% confidence interval [CI] .43-.84%) and 0.33% (18/5400, 95% CI .21-.53%), respectively. In the upper- and lower-bound risk estimates, each index case infected 0.19 (SD 0.45) and 0.10 (SD 0.32) cases, respectively. The seats immediately adjacent to the index cases had an AR of 9.2% (95% CI 5.7-14.4%), with a relative risk 27.8 (95% CI 14.4-53.7) compared to other seats in the upper limit estimation. The middle seat had the highest AR (0.7%, 95% CI .4%-1.2%). The upper-bound AR increased from 0.7% (95% CI 0.5%-1.0%) to 1.2% (95% CI .4-3.3%) when the co-travel time increased from 2.0 hours to 3.3 hours. CONCLUSIONS: The ARs among travelers varied by seat distance from the index case and joint travel time, but the variation was not significant between the types of aircraft. The overall risk of SARS-CoV-2 transmission during domestic travel on planes was relatively low. These findings can improve our understanding of COVID-19 spread during travel and inform response efforts in the pandemic.

Genomic Evidence of In-Flight SARS-CoV-2 Transmission, India to Australia, April 2021.

Epidemiologic and genomic investigation of SARS-CoV-2 infections associated with 2 repatriation flights from India to Australia in April 2021 indicated that 4 passengers transmitted SARS-CoV-2 to >11 other passengers. Results suggest transmission despite mandatory mask use and predeparture testing. For subsequent flights, predeparture quarantine and expanded predeparture testing were implemented.

The epidemiology of airplane headache: A cross-sectional study on point prevalence and characteristics in 50,000 travelers.

BACKGROUND: The current knowledge on the epidemiology and clinical manifestation of airplane headache is mostly derived from case series and small cohort studies without evidence from large populations. METHODS: This cross-sectional study was conducted over a five-month period in the arrival area of two international airports in Germany. 50,000 disembarking passengers were addressed about headaches during their flight to determine headache prevalence, and those confirming and willing to participate underwent a structured interview. RESULTS: Headache during travel was reported by 374 passengers (0.75%), and 301 underwent a structured interview. One hundred and one (0.2%) met the diagnostic criteria of airplane headache. Six passengers suffered from migraines and 134 from tension-type headaches. The differences in the age and gender distribution between the airplane headache and non-airplane headache groups were not statistically significant. The onset (79.2%), duration (82.2%), and location (73.3%) of airplane headache mostly complied with current diagnostic criteria but pain intensity (42.6%) and quality (42.6%) did less so. CONCLUSION: Our data suggest a substantially lower prevalence of airplane headaches than previously reported. The pain intensity and quality seem less characteristic than assumed, suggesting a need to refine the current diagnostic criteria.

Airplane flights triggering spontaneous intracranial hypotension: Observations from the Danish headache centre.

OBJECTIVE: Spontaneous intracranial hypotension (SIH) manifests as orthostatic headache, which can be confirmed by radiological signs of low intracranial pressure on magnetic resonance imaging of the brain. The most common mechanisms of SIH are ruptured meningeal diverticula, ventral dural tears and CSF-venous fistulas. SIH is associated with connective tissue disorders, and cases of SIH onset after trivial trauma have been reported. As SIH is often underdiagnosed, the aim of this study is to identify possible new risk factors of SIH onset in a case series of SIH patients. MATERIALS AND METHODS: We retrospectively reviewed the medical records of 36 patients diagnosed with SIH. We reviewed and identified potential factors that led to or presented at headache onset in SIH patients. RESULTS: We identified 4/36 (11%) patients that had a close temporal relationship between the onset of SIH symptoms and airplane travel. In all four patients, the clinical and imaging features confirmed the diagnosis of SIH. CONCLUSION: This is the first report of a case series of four patients with SIH that could be related to airplane travel. Describing four cases (11%) is not proof but should alert us to a possible causal relationship, which calls for further research. We suggest that when taking medical history, thorough details about the patient's activities, such as headache onset, should be documented because of their importance in correctly diagnosing SIH, which is a debilitating, yet treatable, disease.

Airplane cabin mixing ventilation with time-periodic supply: Contaminant mass fluxes and ventilation efficiency.

Airplane cabin ventilation is essential to ensure passengers' well-being. The conventional ventilation method is mixing ventilation with a statistically steady supply, which, according to former studies, has reached its limits regarding, for example, the ventilation efficiency. However, the effect of a statistically unsteady (time-periodic) supply on the mixing ventilation efficiency has remained largely unexplored. This research uses computational fluid dynamics (CFD) with the large eddy simulation (LES) approach to study isothermal time-periodic mixing ventilation in a section of a single-aisle airplane cabin model, in which the air exhaled by the passengers functions as (passive) contaminants. Two time-periodic supply strategies are evaluated. The induced time-periodic airflow patterns promote an efficient delivery of fresh air to the passenger zone and affect the passengers' expiratory plumes. This results in increased mean contaminant mass fluxes, causing a strong reduction of the mean contaminant concentrations in the passenger zone (up to 23%) and an increased contaminant extraction from the cabin. Mean velocities increase with up to 55% but remain within the comfortable range. It is shown that the ventilation efficiency improves; that is, the contaminant removal effectiveness and air change efficiency (in the full cabin volume) increase with up to 20% and 7%, respectively.

A Neural Algorithm for the Detection and Correction of Anomalies: Application to the Landing of an Airplane.

The location of the plane is key during the landing operation. A set of sensors provides data to get the best estimation of plane localization. However, data can contain anomalies. To guarantee correct behavior of the sensors, anomalies must be detected. Then, either the faulty sensor is isolated or the detected anomaly is filtered. This article presents a new neural algorithm for the detection and correction of anomalies named NADCA. This algorithm uses a compact deep learning prediction model and has been evaluated using real and simulated anomalies in real landing signals. NADCA detects and corrects both fast-changing and slow-moving anomalies; it is robust regardless of the degree of oscillation of the signals and sensors with abnormal behavior do not need to be isolated. NADCA can detect and correct anomalies in real time regardless of sensor accuracy. Likewise, NADCA can deal with simultaneous anomalies in different sensors and avoid possible problems of coupling between signals. From a technical point of view, NADCA uses a new prediction method and a new approach to obtain a smoothed signal in real time. NADCA has been developed to detect and correct anomalies during the landing of an airplane, hence improving the information presented to the pilot. Nevertheless, NADCA is a general-purpose algorithm that could be useful in other contexts. NADCA evaluation has given an average F-score value of 0.97 for anomaly detection and an average root mean square error (RMSE) value of 2.10 for anomaly correction.

Stroke in Airplane Passengers: A Study from a Large International Hub.

INTRODUCTION: Stroke in air travelers is being increasingly recognized. We report on stroke among passengers arriving at or transiting through a busy air travel hub. METHODS: The stroke database of the sole tertiary care center for stroke in a large busy international hub was interrogated. Demographic data of transit passengers, their stroke risk factors, stroke severity, National Institutes of Health Stroke Scale (NIHSS), acute stroke interventions, discharge status and outcome utilizing the Modified Raking scale (mRS) were retrieved and compared between passengers and non-passenger controls. RESULTS: Forty-three flight-related stroke patients were compared to 2564 non-passenger stroke patients. The mean age in the flight-related stroke group was 59.53±10.83 years, 30/43 (69.8%) were males. The stroke subtypes were ischemic in 30 (69.8%) patients, hemorrhagic in 9 (20.9%), and transient ischemic attack in 3 (7.0%), with one cerebral sinus venous thrombosis (2.3%). The mean NIHSS score was 7.79±6.44 in passengers, demonstrating moderate severity. Ten patients (23.3%) received thrombolysis, one (2.3%) received thrombectomy, and one (2.3%) received both thrombolysis and thrombectomy. Outcomes, 54.8% had a good outcome (mRS 0-2), and 45.2% had dependence/death (mRS 3-6). CONCLUSION: Air passengers with stroke were found to be older with more severe strokes and a higher probability of receiving acute stroke treatment compared to non-passengers. Increased awareness with appropriate and timely recognition and triaging of transit passengers with stroke is warranted.

Travel-Associated Venous Thromboembolism.

INTRODUCTION: Long-distance travel is assumed to be a risk factor for venous thromboembolism (VTE). However, the available data have not clearly demonstrated the strength of this relationship, nor have they shown evidence for the role of thromboprophylaxis. METHODS: We performed a systematic review of the literature. We also summarized available guidelines from 5 groups. RESULTS: We found 18 studies that addressed this question. Based on the data presented in the review, we conclude that there is an association between VTE and length of travel, but this association is mild to moderate in effect size with odds ratios between 1.1 and 4. A dose-response relationship between VTE and travel time was identified, with a 26% higher risk for every 2 h of air travel (P=0.005) starting after 4 h. The quality of evidence for both travel length and thromboprophylaxis was low. However, low-risk prophylactic measures such as graduated compression stockings were shown to be effective in VTE prevention. There is heterogeneity among the different practice guidelines. The guidelines generally concur that no prophylaxis is necessary in travelers without known thrombosis risk factors and advocate for conservative treatment such as compression stockings over pharmacologic prophylaxis. CONCLUSIONS: We conclude air travel is a risk factor for VTE and that there is a dose relationship starting at 4 h. For patients with risk factors, graduated compression stockings are effective prophylaxis.

Behaviors, movements, and transmission of droplet-mediated respiratory diseases during transcontinental airline flights.

With over 3 billion airline passengers annually, the inflight transmission of infectious diseases is an important global health concern. Over a dozen cases of inflight transmission of serious infections have been documented, and air travel can serve as a conduit for the rapid spread of newly emerging infections and pandemics. Despite sensational media stories and anecdotes, the risks of transmission of respiratory viruses in an airplane cabin are unknown. Movements of passengers and crew may facilitate disease transmission. On 10 transcontinental US flights, we chronicled behaviors and movements of individuals in the economy cabin on single-aisle aircraft. We simulated transmission during flight based on these data. Our results indicate there is low probability of direct transmission to passengers not seated in close proximity to an infectious passenger. This data-driven, dynamic network transmission model of droplet-mediated respiratory disease is unique. To measure the true pathogen burden, our team collected 229 environmental samples during the flights. Although eight flights were during Influenza season, all qPCR assays for 18 common respiratory viruses were negative.

In-Flight Tests of Intruder Detection Vision System.

In the near future, the integration of manned and unmanned aerial vehicles into the common airspace will proceed. The changes taking place mean that the safety of light aircraft, ultralight aircraft and unmanned air vehicles (UAV) will become an increasing problem. The IDAAS project (Intruder Detection And collision Avoidance System) meets the new challenges as it aims to produce technically advanced detection and collision avoidance systems for light and unmanned aerial vehicles. The work discusses selected elements of research and practical tests of the intruder detection vision system, which is part the of IDAAS project. At the outset, the current formal requirements related to the necessity of installing anticollision systems on aircraft are presented. The concept of the IDAAS system and the structure of algorithms related to image processing are also discussed. The main part of the work presents the methodology developed for the needs of dedicated flight tests, its implementation and the results obtained. The initial tests of the IDAAS system carried out on an ultralight aircraft generally indicate the possibility of the effective detection of intruders in the airspace with the use of vision methods, although they also indicated the existence of conditions in which this detection may prove difficult or even impossible.

Prevalence of Headache Attributed to Airplane Travel Among Medical Students in Brazil.

BACKGROUND: Headache attributed to airplane travel is a rare form of headache that develops exclusively during airplane travel. It is characterized by occurring during takeoff, landing, or both, and improves spontaneously within 30 minutes after the ascent or descent of the airplane is completed. OBJECTIVES: Our objectives were to determine the prevalence of headache attributed to airplane travel among medical students who traveled by plane, the time of flight when it occurred, and the emotional state of passengers on new trips. METHODS: The study was prospective, cross-sectional, using a non-random sample of medical students who traveled by plane. In total, 155 passengers who traveled by plane on at least 3 flights, regardless of duration were interviewed. RESULTS: Headache during flight occurred 3 or more times in 7.5% (80/1070) of the trips and 14.2% (22/155) of the passengers, especially during takeoff or landing (17/22; 77.3%), having a stabbing character and lasting less than 30 minutes. The headache improved spontaneously at the end of the landing phase (17/22; 77.3%). When traveling again, 68.2% (15/22) of passengers traveled normally, despite previous painful experience. CONCLUSIONS: This study demonstrated that headache attributed to airplane travel is not as rare as previously thought, being predominant during takeoff or landing. In addition, despite the bothersome feeling, most passengers who experienced this headache traveled normally, despite previous painful experience.

Energy Harvesting Technologies for Structural Health Monitoring of Airplane Components-A Review.

With the aim of increasing the efficiency of maintenance and fuel usage in airplanes, structural health monitoring (SHM) of critical composite structures is increasingly expected and required. The optimized usage of this concept is subject of intensive work in the framework of the EU COST Action CA18203 "Optimising Design for Inspection" (ODIN). In this context, a thorough review of a broad range of energy harvesting (EH) technologies to be potentially used as power sources for the acoustic emission and guided wave propagation sensors of the considered SHM systems, as well as for the respective data elaboration and wireless communication modules, is provided in this work. EH devices based on the usage of kinetic energy, thermal gradients, solar radiation, airflow, and other viable energy sources, proposed so far in the literature, are thus described with a critical review of the respective specific power levels, of their potential placement on airplanes, as well as the consequently necessary power management architectures. The guidelines provided for the selection of the most appropriate EH and power management technologies create the preconditions to develop a new class of autonomous sensor nodes for the in-process, non-destructive SHM of airplane components.

Remaining Useful Life Prediction of Airplane Engine Based on PCA-BLSTM.

The accurate prediction of airplane engine failure can provide a reasonable decision basis for airplane engine maintenance, effectively reducing maintenance costs and reducing the incidence of failure. According to the characteristics of the monitoring data of airplane engine sensors, this work proposed a remaining useful life (RUL) prediction model based on principal component analysis and bidirectional long short-term memory. Principal component analysis is used for feature extraction to remove useless information and noise. After this, bidirectional long short-term memory is used to learn the relationship between the state monitoring data and remaining useful life. This work includes data preprocessing, the construction of a hybrid model, the use of the NASA's Commercial Aerodynamic System Simulation (C-MAPSS) data set for training and testing, and the comparison of results with those of support vector regression, long short-term memory and bidirectional long short-term memory models. The hybrid model shows better prediction accuracy and performance, which can provide a basis for formulating a reasonable airplane engine health management plan.

Headache Attributed to Aeroplane Travel: An Historical Outline.

INTRODUCTION: Headache attributed to aeroplane travel (AH) is one of the new nosological entries in the International Classification of Headache Disorders (ICHD) 3 beta. MATERIALS AND METHODS: This study retraces the history of headache related to flight, from the initial description to the modern reports, on the basis of original sources. RESULTS: Head pain related to flight has been reported since the beginning of flight era. However, most of those early cases are easily recognized as secondary to an exceptional barotrauma and/or a sinusitis concomitant with the flight. Instead, contemporary research identified a new nosological entity, AH, which by definition occurs in normal flying conditions and in absence of any sinus pathology. Moreover, we identified recently similar forms of headache, triggered by sudden changes of external pressure (rapid descent from mountain, mountain descent headache, MDH); and ascent from diving, diving ascent headache (DAH). CONCLUSION: Head pain related to flight has been reported since the origin of aviation, but it was caused by an exceptional barotrauma or a respiratory infection. Instead, AH occurs in normal flying conditions. Two newly identified conditions, MDH and DAH, appear to share a common pathogenetic mechanism with AH: namely the imbalance between intrasinusal and external air pressure. Therefore, we assert that an expansion of this entity of AH is something that should be considered in the next ICHD.

Sherpas, Coca Leaves, and Planes: High Altitude and Airplane Headache Review with a Case of Post-LASIK Myopic Shift.

PURPOSE OF REVIEW: High altitude headache is a common neurological symptom that is associated with ascent to high altitude. It is classified by the International Classification of Headache Disorders, 3rd Edition (ICHD-3) as a disorder of homeostasis. In this article, we review recent clinical and insights into the pathophysiological mechanisms of high altitude and airplane headache. We also report a second case of post-LASIK myopic shift at high altitude exposure secondary hypoxia. Headache attributed to airplane travel is a severe typically unilateral orbital headache that usually improves after landing. This was a relative recent introduction to the ICHD-3 diagnostic criteria. Headache pain with flight travel has long been known and may have been previously considered as a part of barotrauma. Recent studies have helped identify this as a distinct headache disorder. RECENT FINDINGS: Physiologic, hematological, and biochemical biomarkers have been identified in recent high altitude studies. There have been recent advance in identification of molecular mechanisms underlying neurophysiologic changes secondary to hypoxia. Calcitonin gene-related peptide, a potent vasodilator, has been implicated in migraine pathophysiology. Recent epidemiological studies indicate that the prevalence of airplane headache may be more common than we think in the adult as well at the pediatric population. Simulated flight studies have identified potential biomarkers. Although research is limited, there have been advances in both clinical and pathophysiological mechanisms associated with high altitude and airplane headache.

Diving Headache.

This review will focus on the most recent information regarding the ICHD-3 definition of diving headache as well as other important causes of diving headache that are not listed in the ICHD-3 classification system. The paper will discuss etiology, diagnosis, and management of these disorders, focusing, when possible, on the newest research available. ICHD-3 diving headache is due to hypercapnia and is treated accordingly with oxygen. Other causes of diving headache range from decompression sickness to external compression headache to primary headache disorders, such as migraine. Correctly determining the underlying cause of the diving headache is critical to management and relies on history taking and physical exam. The pathophysiology of newly described types of diving headache, such as diving ascent headache, remains under investigation but may be related to other homeostatic headache causes, such as airplane headache. Further investigation may yield more information regarding management as well as possible insight into other headache disorders.

Headache and Barometric Pressure: a Narrative Review.

PURPOSE OF REVIEW: Alterations in atmospheric pressure have been long associated with headaches. The purpose of this review article is to investigate the association of barometric pressure with headache, classifying into two broad categories primary headache disorders (barometric pressure triggering migraine or tension-type headache) and secondary headache disorders (barometric pressure triggering high-altitude headache and headache attributed to airplane travel), discussing the pathophysiology and possible treatments. RECENT FINDINGS: Multiple studies have been performed with inconsistent results regarding the directionality of the association between atmospheric pressure changes and triggering of primary headache disorders, chiefly headaches. Atmospheric pressure is also a trigger of two secondary headache disorders, i.e., high-altitude headache and headache attributed to airplane travel. Hypothesized mechanisms include excitation of neurons in trigeminal nucleus, central and peripheral vasoconstriction, barotrauma, and hypoxia. There are no randomized clinical trials regarding effective acute or preventive treatments. Greater understanding of pathophysiology may enable both acute and preventive treatments for headaches triggered by changes in barometric pressure. Further studies on the subject are needed.

Headache Attributed to Airplane Travel: A Review of Literature.

PURPOSE OF REVIEW: Headaches due to airplane travel are rare but documented in the literature. We aim to provide a review of diagnostic criteria and treatment for this condition. RECENT FINDINGS: Several cases of this syndrome have been reported since it was first described in 2004. Airplane headache is classified as unilateral, stabbing, orbito-frontal pain, lasting under 30 min, and occurs during ascent or descent of a plane. Patients with this condition can develop anxiety and fear of flying given the intensity and severity of the pain. The pathophysiology of this syndrome is unknown, but theories include suspected barotrauma given changes in barometric pressure during ascent and descent. There are no randomized controlled trials regarding treatment, but case reports suggest headache prevention with pre-treatment with naproxen, decongestants, and triptans prior to air travel. Some non-pharmacological therapies reported include Valsalva maneuvers, chewing, relaxation techniques, and pressure at the pain area. As more cases of headache attributed to airplane travel are reported, epidemiological data can be obtained to further understand the incidence and prevalence of this condition, which can lead to improved treatment options for patients.