In-flight Oxygen Research Articles

Can resting lung function predict the response of a person living with motor neuron disease to a hypoxic challenge test?

People living with MND (PlwMND) are at risk of altitude-related hypoxia during flight. The Hypoxic Challenge Test (HCT) determines whether in-flight oxygen is required but can be expensive and inaccessible. To assist with travel recommendations, we investigated the relationship between altitude simulation-induced hypoxemia and baseline lung function. Retrospective audit of clinical database of PlwMND who had HCT and lung function. Pearson's correlation assessed relationships between oxygen saturation at altitude (AltSpO2) and lung function. Univariate logistic regression analysis and receiver operator characteristic (ROC) curves determined associations between lung function and HCT pass or fail. Between 2004-2023, 50 PlwMND were identified (median (IQR) diagnosis to HCT = 11.6 (16.9) months, mean ± SD forced vital capacity (FVC) = 2.4 ± 0.9 liters). Ten patients dropped below 85% SpO2 during testing (HCT fail). Baseline SpO2 was associated with AltSpO2 (r = 0.64) and predicted HCT pass or fail (OR 2.0 [95% CI 1.2-3.4], area under ROC curve (AUC) =0.8 [0.6-1.0]), as did FVC (AUC = 0.8 [0.6-0.9]). PlwMND with a FVC > 2.7L or a resting SpO2 > 97% are likely to pass HCT, whereas all those with FVC < 1L and SpO2 < 92% failed. PlwMND with FVC >2.7L or SpO2 >97% are unlikely to require oxygen or ventilatory supports for airline travel. A FVC below 2.7L will require a HCT to confidently determine HCT outcome, with testing still required for FVC <1L or baseline SpO2 <92%, to provide evidence to the airlines for in-flight respiratory support.

COPD patients' pre-flight check: A narrative review.

For most of the people with stable and well-controlled chronic obstructive pulmonary disease (COPD), air travel is safe and comfortable, but the flight environment may pose clinical challenges. This narrative review aims to update the requirements for allowance to fly of people with COPD without chronic respiratory failure. A literature review was performed on platforms: Pubmed, Scopus and Ovid, for citations in English from 2000 to 2021. The following key words were used: COPD AND: air-travel, in-flight hypoxemia, fitness to air travel. Official regulatory documents and guidelines were also examined. Current air travel statements recommend supplemental oxygen when in flight arterial oxygen tension (PaO2) is expected to fall below 6.6 or 7.3 kPa. Several lung function variables, prediction equations and algorithms have been proposed to estimate in-flight PaO2, the need for in-flight supplemental oxygen, and to select individuals needing more advanced pre-flight testing, such as the hypoxia-altitude simulation test. Exercise induced desaturation and aerobic capacity correlate significantly with in-flight PaO2. COPD patients with late intensification of disease, new changes in medications, recent acute exacerbation/ hospitalization or anticipated emotional and physical stress during the proposed air-travel should be carefully evaluated by the caring family or specialist physician.

Evacuation Strategies for U.S. Casualties with Traumatic Brain Injury (TBI) with and without Polytrauma.

According to the Military Health System Traumatic Brain Injury (TBI) Center of Excellence, 51,261 service members suffered moderate to severe TBI in the last 21 years. Moderate to severe TBI in service members is usually related to blast injury in combat operations, which necessitates medical evacuation to higher levels of care. Prevention of secondary insult, and mitigation of the unique challenges associated with the transport of TBI patients in a combat setting are important in reducing the morbidity and mortality associated with this injury. The primary goal of this study was a secondary analysis comparing the impact of time to transport on clinical outcomes for TBI patients without polytrauma versus TBI patients with polytrauma transported out of the combat theater via Critical Care Air Transport Teams (CCATT). Our secondary objective was to describe the occurrence of in-flight events and interventions for TBI patients without polytrauma versus TBI with polytrauma to assist with mission planning for future transports. We performed a secondary analysis of a retrospective cohort of 438 patients with TBI who were evacuated out of theater by CCATT from January 2007 to May 2014. Polytrauma was defined as abbreviated injury scale (AIS) of at least three to another region in addition to head/neck. Time to transport was defined as the time (in days) from injury to CCATT evacuation out of combat theater. We calculated descriptive statistics and examined the associations between time to transport and preflight characteristics, in-flight interventions and events, and clinical outcomes for TBI patients with and without polytrauma. We categorized patients into two groups, those who had a TBI without polytrauma (n = 179) and those with polytrauma (n = 259). Within each group, we further divided those that were transported within 1 day of injury, in 2 days, and 3 or more days. Patients with TBI without polytrauma transported in 1 or 2 days were more likely to have a penetrating injury, an open head injury, a preflight Glascow Coma Score (GCS) of 8 or lower, and be mechanically ventilated compared to those transported later. Patients without polytrauma who were evacuated in 1 or 2 days required more in-flight interventions compared to patients without polytrauma evacuated later. Patients with polytrauma who were transported in 2 days were more likely to receive blood products, and patients with polytrauma who were evacuated within 1 day were more likely to have had at least one episode of hypotension en route. Polytrauma patients who were evacuated in 2-3 days had higher hospital days compared to polytrauma with earlier evacuations. There was no significant difference in mortality between any of the groups. In patients with moderate to severe TBI transported via CCATT, early evacuation was associated with a higher rate of in-flight hypotension in polytrauma patients. Furthermore, those who had TBI without polytrauma that were evacuated in 1-2 days received more in-flight supplementary oxygen, blood products, sedatives, and paralytics. Given the importance of minimizing secondary insults in patients with TBI, recognizing this in this subset of the population may help systematize ways to minimize such events. Traumatic Brain Injury patients with polytrauma may benefit from further treatment and stabilization in theater prior to CCATT evacuation.

Physiological predictors of Hypoxic Challenge Testing (HCT) outcomes in Interstitial Lung Disease (ILD).

Pre-flight risk assessments are currently recommended for all Interstitial Lung Disease (ILD) patients. Hypoxic challenge testing (HCT) can inform regarding the need for supplemental in-flight oxygen but variables which might predict the outcome of HCT and thus guide referral for assessment, are unknown. A retrospective analysis of ILD patients attending for HCT at three tertiary care ILD referral centres was undertaken to investigate the concordance between HCT and existing predictive equations for prediction of in-flight hypoxia. Physiological variables that might predict a hypoxaemic response to HCT were also explored with the aim of developing a practical pre-flight assessment algorithm for ILD patients. A total of 106 ILD patients (69 of whom (65%) had Idiopathic Pulmonary Fibrosis (IPF)) underwent HCT. Of these, 54 (51%) patients (of whom 37 (69%) had IPF) failed HCT and were recommended supplemental in-flight oxygen. Existing predictive equations were unable to accurately predict the outcome of HCT. ILD patients who failed HCT had significantly lower resting SpO2, baseline PaO2, reduced walking distance, FEV1, FVC and TLCO, but higher GAP index than those who passed HCT. TLCO >50% predicted and PaO2 >9.42 kPa were independent predictors for passing HCT. Using these discriminators, a novel, practical pre-flight algorithm for evaluation of ILD patients is proposed.

Blood-Injection-Injury (B-I-I) Specific Phobia Affects the Outcome of Hypoxic Challenge Testing

Blood-injection-injury (B-I-I) phobia is capable of producing inaccurate hypoxic challenge testing results due to anxiety-induced hyperventilation. A 69-yr-old woman with a history of hypersensitivity pneumonitis, restrictive spirometry, exercise desaturation requiring supplementary oxygen on mobilizing, reduced DLco, and B-I-I phobia was referred for hypoxic challenge testing (HCT) to assess in-flight oxygen requirements. HCT was performed by breathing a 15% FIo2 gas mixture, simulating the available oxygen in ambient air onboard aircraft pressurized to an equivalent altitude of 8000 ft. Spo2 fell to a nadir value of 81% during HCT, although it rapidly increased to 89% during the first of two attempts at blood gas sampling. A resultant blood gas sample showed an acceptable Po2 outside the criteria for recommending in-flight oxygen and a reduced Pco2. Entering the nadir Spo2 value into the Severinghaus equation gives an estimated arterial Po2 of 6 kPa (45 mmHg), which was felt to be more representative of resting values during HCT, and in-flight oxygen was recommended. While hyperventilation is an expected response to hypoxia, transient rises in Spo2 coinciding with threat of injury are likely to be attributable to emotional stress-induced hyperventilation, characteristic of B-I-I specific phobia and expected during the anticipation of exteroceptive threat, even in normal subjects. In summary, should excessive hyperventilation be detected during HCT and coincide with transient increases in Spo2, HCT should be repeated using Spo2 only as a guide to the level of hypoxemia, and Spo2 maintained using supplementary oxygen in accordance with alternative methods described in guidelines.Spurling KJ, McGoldrick VP. Blood-injection-injury (B-I-I) specific phobia affects the outcome of hypoxic challenge testing. Aerosp Med Hum Perform. 2017; 88(5):503-506.

Hypoxic Challenge Testing for Fitness to Fly with Severe Asthma.

Commercial airline travel poses a recognized risk to patients with respiratory disease, including in those with asthma. Hypoxic challenge testing (HCT) is typically employed to mitigate this risk by dictating in-flight oxygen requirement. The role of HCT has not been formally studied in patients with severe asthma and we therefore evaluated HCT assessment in a cohort of patients with severe asthma (N = 37). Over half (57%) of patients had a positive HCT. Baseline oxygen saturation (S(p)o(2)) was poorly predictive of a recommendation for supplementary oxygen in flight; two-thirds of those deemed to require oxygen had a baseline S(p)o(2) > 95%. A combination of any two of: P(a)o(2) ≤ 10.5 kPa, FEV(1) ≤ 60% predicted, and PEF ≤ 350 L · min(-1) predicted the need for in-flight oxygen with a sensitivity of 89% and a specificity of 69%. Furthermore, no patient with an S(p)o(2) > 95% and FEV(1) > 85% predicted had a positive HCT. Overall, the findings indicate that HCT should be considered for all patients with severe asthma, regardless of resting oxygen saturation level.

Fitness to Fly Testing in Patients with Congenital Heart and Lung Disease

During commercial air travel passengers are exposed to a low ambient cabin pressure, comparable to altitudes of 5000 to 8000 ft (1524 to 2438 m). In healthy passengers this causes a fall in partial pressure of oxygen, which results in relative hypoxemia, usually without symptoms. Patients with congenital heart or lung disease may experience more severe hypoxemia during air travel. This systematic review provides an overview of the current literature focusing on whether it is safe for patients with congenital heart or lung disease to fly. The Pubmed database was searched and all studies carried out at an (simulated) altitude of 5000-8000 ft (1524-2438 m) for a short time period (several hours) and related to patients with congenital heart or lung disease were reviewed. Included were 11 studies. These studies examined patients with cystic fibrosis, neonatal (chronic) lung disease and congenital (a)cyanotic heart disease during a hypoxic challenge test, in a hypobaric chamber, during commercial air travel, or in the mountains. Peripheral/arterial saturation, blood gases, lung function, and/or the occurrence of symptoms were listed. Based on the current literature, it can be concluded that air travel is safe for most patients. However, those at risk of hypoxia can benefit from supplemental in-flight oxygen. Therefore, patients with congenital heart and lung disease should be evaluated carefully prior to air travel to select the patients at risk for hypoxia using the current studies and guidelines.

Pressure effects on the nose by an in-flight oxygen mask during simulated flight conditions

BackgroundDutch F-16 fighter pilots experience oxygen mask inflicted nasal trauma, including discomfort, pain, skin abrasions, bruises and bone remodelling. Pressure and shear forces on the nose might contribute to causing...

Exostoses of the Bony Pyramid of the Nose: A Review About an Adaptive Response to Mechanical Stimuli Exerted by In-Flight Oxygen Masks

This review addresses thickening of the bony pyramid of the nose, a condition that is caused by in-flight oxygen masks in otherwise healthy Royal Netherlands Air Force (RNLAF) F-16 pilots. The overlying skin may show temporary or permanent reddening, irritation, thickening and may become painful. Both in vitro and in vivo animal research has shown that mechanical stimuli are converted into a biochemical response through a process called mechanotransduction. Examination of the RNLAF F-16 pilots showed that the oxygen mask exerts pressure and friction on the nose. The biochemical response to chronic exposure to these stimuli results in the development of skin conditions and eventually exostoses of the bony pyramid of the nose. Painful skin conditions are most frequently observed, while the development of exostoses is rare. It lies at the extreme end of the spectrum of the pilots’ nasal conditions. The suboptimal fit of their work gear probably contributes to the pilots’ soft and bony tissue nasal conditions. Explaining the pathogenesis of the development of exostoses may aid in the development of preventive measures. Also, the obtained knowledge may be of use in similar occupational health issues that involve mechanical loading. Our conclusions are that areas containing osteocyte precursors and covered by a relatively thin cushioning layer are prone to develop a soft tissue and bony tissue response when they are chronically exposed to intermittently exerted, mechanical stimuli of sufficiently high magnitude. Modification of the suboptimally fitting oxygen mask–helmet assembly is needed to prevent symptoms associated with its use.

G397(P) Hypoxic challenge testing – which children are we assessing?

Aim Hypoxic challenge testing (HCT) is the method used to assess whether a patient with stable respiratory disease requires in-flight oxygen. A national guideline, published by British Thoracic Society in 2011, makes recommendations on which children ought to undergo HCT prior to undertaking air travel. Identified are: infants under 1 year with neonatal history of chronic lung disease, children with CF/chronic lung disease old enough for spirometry whose FEV1 This audit aimed to define which patients had undergone hypoxic challenge tests and compared this against the patient groups identified in the BTS guideline. Methods A large tertiary children’s hospital in the UK conducted a retrospective audit of hypoxic challenge tests carried out between 2012 and 2014. Information was collected on age, diagnosis, when the patient last required long-term oxygen, lung function around the time of the test and the outcome of the test. Results 31 HCTs from 25 patients were audited. The average age was 6.3 years (6 months-16.5 years). Of the 22 patients who passed the HCT, three were recommended in the guideline to have HCT. Of the nine patients who did not pass HCT, two were within the recommendations. These five patients, who were within the recommendations, were three children with CF/chronic lung disease with FEV1 Of the nine children who did not pass the HCT, seven fell outside the recommended groups. Five were ex-preterm children older than one year had history of neonatal chronic lung disease, one had SMA Type 2, one had muscular dystrophy, one had severe kyphoscoliosis and one had severe restrictive lung disease following PNET. Conclusion Results show that clinicians are choosing to preform hypoxic challenge tests on patient outside of the recommendations. A larger proportion who failed the hypoxic challenge test were not defined within the BTS guidelines. With advancing technology the demographics of our respiratory paediatric patient population is evolving. It is therefore prudent to reconsider the paediatric recommendations.

Concordance between hypoxic challenge testing and predictive equations for hypoxic flight assessment in chronic obstructive pulmonary disease patients prior to air travel

BackgroundPatients with chronic pulmonary diseases are at increased risk of hypoxemia when traveling by air. Screening guidelines, predictive equations based on ground level measurements and altitude simulation laboratory procedures have been recommended for determining risk but have not been rigorously evaluated and compared. Therefore we aimed to explore the correlation and concordance between hypoxic challenge testing and predictive equations for assessment and prediction of in-flight hypoxia in chronic obstructive pulmonary disease patients prior to air travel. DesignComparative study. MethodsThirty five chronic obstructive pulmonary disease patients were studied. Spirometry data were recorded prior to hypoxic inhalation test and blood gases were analyzed before and after hypoxic inhalation and when SpO2⩽85%. Hypoxic inhalation test was performed using the ventimask method. The PaO2 at altitude was estimated using four published predictive equations, which use values of PaO2 (ground) and lung function measurements to predict altitude PaO2. Results were interpreted using the BTS recommendations for prescription of in-flight oxygen and to assess agreement between hypoxic inhalation test results and each of the predictive equations. ResultsGround PaO2 was significantly decreased following hypoxic inhalation test. ConclusionsThe present study supports on-HCT as a reliable, on-invasive and continuous methods determining the requirement for in-flight O2 are relatively constant. Predictive equations considerably overestimate the need for in-flight O2 compared to hypoxic inhalation test. Predictive equations are cheap, readily available methods of flight assessment, but this study shows poor agreement between their predictions and the measured individual hypoxic responses during HCT.

Exerted pressure by an in-flight oxygen mask.

F-16 pilots wear an in-flight oxygen mask to prevent hypoxemia. In the contact area with the mask, the pilots experience nasal discomfort and pain, and may even develop nasal deformities. A likely cause is the pressure exerted by the mask. In this study the hypothesis was that the change in pressure exerted on the nose would be higher than on the chin, an area free of symptoms. Six F-16 pilots and five healthy former F-16 pilots volunteered to participate in this observational pilot study. At baseline the pilots donned mask and helmet. The median delta pressure (deltap) recordings at baseline were compared to the exerted deltap during the experimental head movements. At baseline, there was no significant difference between the median deltap on the nose and chin (2 vs. 1.6 mmHg, T = 2). Head movements increased the median deltap on the nose by 50 mmHg (T = 0) and on the chin by 31 mmHg (T = 0) when compared to baseline. Head movements also decreased the pressure by -20 mmHg (T = 1.75) on the nose and -11 mmHg (T = 0) on the chin. The data show that the baseline deltap is higher on the nose than on the chin. The head movements both increased and decreased the exerted pressure on the nose and the chin. These observations suggest that further evaluation of the effect of flight conditions on the exerted pressure is worthwhile to understand its contribution to the nasal symptoms.

Demonstration of Compact Air Separation Technology for In-Flight Oxygen Collection Space Launchers

In-flight oxygen collection enables a significant reduction in takeoff gross weight of space launchers, thereby allowing airplane-like operations. This paper describes the development and tests of a compact rotary air separation device that constitutes a part of a functional oxygen collection plant. The experimental results are described in detail, demonstrating a consistent and long duration operation of the device yielding a high purity of liquid enriched air (96% oxygen) while causing only very small pressure drops on the gaseous phase. The tests indicate that the height of a so-called ideal tray for the current device is around 1 to 2 cm of core foam material, which is an improvement of one order of magnitude compared with previous designs. The experimental results are scaled up and applied to two different two stage to orbit launch vehicles. It is shown that a complete oxygen collection plant for a subsonic collection phase would weigh around 4 tons and occupy approximately , which represents less than 1% of the vehicle takeoff weight and a specific mass and volume, respectively, of and of liquid oxygen generated. For a supersonic collection, a much bigger collection plant is required due to a much higher oxygen production rate, and further improvements are required to reduce its system mass and volume despite a reduction in both specific mass and volume.

Last call for the flight simulation test?

“Dear Colleague, Please see and advise on this patient with COPD who wishes to fly”. This is a common request from our non-respiratory colleagues and although we have guidelines to follow to assist in answering their queries, the evidence on which the guidelines are based is weak. The most recently published air travel recommendations are those from the British Thoracic Society (BTS) [1], which try to make some sense of the evidence and provide guidance based on expert consensus, but the recommendations for prescribing oxygen during a flight remain, at best, level C. Guidance has therefore had to remain vague in terms of which patients with chronic obstructive pulmonary disease (COPD) should be assessed for in-flight oxygen: those with previous respiratory symptoms during air travel, severe COPD (forced expiratory volume in 1 s <30% predicted) or bullous lung disease. Once these patients have been identified, there is still uncertainty on how to assess them further and the physician can chose between a simple 50-m walk test, using equations to predict the need for oxygen based on predicted partial pressure of oxygen ( P O2) at cabin pressure, or by undertaking a formal high altitude simulation test (HAST), all of which are reviewed in detail in the BTS recommendations [1]. The first test assumes that if a patient can walk 50 m then this indicates sufficient cardiopulmonary reserve to withstand a fall in inspired P O2 (to the equivalent of approximately 15% inspired oxygen at sea level) when flying in commercial aircraft. The second two methods assume that a resulting arterial P O2 ( P aO2) <6.6 kPa (50 mmHg) is a reliable indicator of the need for in-flight oxygen. This cut-off is based on expert consensus [ …

Oxygen Mask Fit Analysis in F-16 Fighter Pilots Using 3D Imaging

The majority of Dutch F-16 pilots experience in-flight oxygen mask related nasal discomfort and injury. We aimed to analyze the fit of the oxygen mask. We successfully scanned 35 pilots with a 3D scanner to measure the distance between the contact area on the nose and the oxygen mask in seven points, and the difference (delta) in angle between the nose and the mask relative to the facial midline. Ill fit was defined as > or = 4 mm distance, or delta > or = 4 degree angle. Intraclass correlation coefficients were used to objectify the reproducibility of the measurements. There were 35 pilots who had > or = 4 mm distance between the nasal dorsum and the mask and 14 pilots had delta > or = 4 degree angle. Reproducibility of the distance measurements was excellent (R > or = 0.93, CI 95% 0.86-0.96) and of the angle measurements was good (R = 0.72, CI 95% 0.5-0.8). The room for displacement that we found may be a contributor to the discomfort. It is indicative of an ill fit of the oxygen mask, since all subjects had complaints. We recommend evaluating whether improved fixation of the mask and simultaneous reduction of the pressure on the nose will improve comfort.

Hypoxic challenge test applied to healthy children: influence of body positions and exertion on pulse oximetric saturation

BackgroundCommercial aircraft are pressurised to ∼2438 m (8000 ft) above sea level that equates breathing 15% oxygen at sea level. A preflight hypoxic challenge test (HCT) is therefore recommended for...

Managing patients with stable respiratory disease planning air travel: a primary care summary of the British Thoracic Society recommendations

Air travel poses medical challenges to passengers with respiratory disease, principally because of exposure to a hypobaric environment. In 2002 the British Thoracic Society published recommendations for adults and children with respiratory disease planning air travel, with a web update in 2004. New full recommendations and a summary were published in 2011, containing key recommendations for the assessment of high-risk patients and identification of those likely to require in-flight supplemental oxygen. This paper highlights the aspects of particular relevance to primary care practitioners with the following key points: (1) At cabin altitudes of 8000 feet (the usual upper limit of in-flight cabin pressure, equivalent to 0.75 atmospheres) the partial pressure of oxygen falls to the equivalent of breathing 15.1% oxygen at sea level. Arterial oxygen tension falls in all passengers; in patients with respiratory disease, altitude may worsen preexisting hypoxaemia. (2) Altitude exposure also influences the volume of any air in cavities, where pressure x volume remain constant (Boyle's law), so that a pneumothorax or closed lung bulla will expand and may cause respiratory distress. Similarly, barotrauma may affect the middle ear or sinuses if these cavities fail to equilibrate. (3) Patients with respiratory disease require clinical assessment and advice before air travel to: (a) optimise usual care; (b) consider contraindications to travel and possible need for in-flight oxygen; (c) consider the need for secondary care referral for further assessment; (d) discuss the risk of venous thromboembolism; and (e) discuss forward planning for the journey.

Air Travel and Chronic Obstructive Pulmonary Disease: A New Algorithm for Pre-flight Evaluation: Edvardsen A, Akero A, Christensen CC, et al. Thorax 2012;67:964–9.

With chronic obstructive pulmonary disease (COPD) increasing in prevalence and air travel becoming progressively accessible, more and more elderly air passengers are at risk for developing severe hypoxemia and respiratory distress after cabin depressurization. To date, the gold-standard instrument used to predict the need for in-flight supplemental oxygen is the hypoxia-altitude simulation test (HAST). Unfortunately, HAST is time-intensive, invasive (it requires multiple arterial blood samples to determine PaO2), and not widely available.

Oxygen Mask Related Nasal Integument and Osteocartilagenous Disorders in F-16 Fighter Pilots

BackgroundA preliminary survey showed half of the participating Royal Netherlands Air Force (RNLAF) F-16 fighter pilots to have nasal integument and osteocartilagenous disorders related to wearing in-flight oxygen masks.AimTo make an inventory of these disorders and possible associated factors.MethodsAll RNLAF F-16 pilots were requested to fill out a semi-structured questionnaire for a cross-sectional survey. Additionally, one squadron in The Netherlands and pilots in operational theater were asked to participate in a prospective study that required filling out a pain score after each flight. Pilot- and flight-related variables on all participants were collected from the RNLAF database. A linear mixed model was built to identify associated factors with the post-flight pain score.ResultsThe response rate to the survey was 83%. Ninety of the 108 participants (88%, 6 missing) reported tenderness, irritation, pain, erythema, skin lesions, callous skin, or swelling of nasal bridge integument or architecture. Seventy-two participants (71%, 6 missing) reported their symptoms to be troublesome after a mean of 6±3 out of 10 flights (0;10, 54 missing). Sixty-six pilots participated in scoring post-flight pain. Pain scores were significantly higher if a participant had ≥3 nasal disorders, after longer than average flights, after flying abroad, and after flying with night vision goggles (respectively +2.7 points, p = 0.003; +0.2 points, p = 0.027; +1.8 points, p = 0.001; +1.2 points p = 0.005). Longer than average NVG flights and more than average NVG hours per annum decreased painscores (respectively −0.8 points, p = 0.017; −0.04 points, p = 0.005).ConclusionsThe majority of the RNLAF F-16 fighter pilot community has nasal disorders in the contact area of the oxygen mask, including pain. Six pilot- or flight-related characteristics influence the experienced level of pain.

Preparing patients with chronic pulmonary disease for air travel

Flying is the most important way of travelling in the continually growing international tourism. Number of passengers and those with preexisting diseases, mainly with cardiopulmonary problems, is increasing over years. One of the main tasks of the pre-travel advice is to assess tolerance to hypoxia of the traveler, and specify the necessity, as well as the type and volume of supplementary oxygen therapy. It is indispensable to know the cabin-environment and impact of that on the travelers' health. Travel medicine specialist has to be aware of the examinations which provide information for the appropriate decision on the fit-to-fly condition of the patient. The physician who prepares the patient with chronic obstructive pulmonary disease for repatriation by regular flight and the escorting doctor have to be fully aware of the possibilities, modalities, advantages and contraindications of the on-board oxygen supply and therapy. In this review, the authors give a summary of literature data, outline the tools of in-flight oxygen therapy as well as discuss possibilities for the preflight assessment of patients' condition including blood gas parameters required for safe air travel, as recommended in international medical literature. The preparation process for repatriation of patients with chronic obstructive pulmonary disease is also discussed.