EditorialIntercontinental air travel: The cabin atmosphere and circadian realignment
Section snippets
The cabin atmosphere
Potential effects of the cabin atmosphere on well being involve the relative hypoxia and the low humidity to which may be added the possibility that the quality of the cabin air supply could be inadequate. The relative hypoxia of the cabin environment is related to the need to limit the differential pressure across the wall of the cabin. Cabin altitudes up to 8000 feet (less than 2500 m) are permitted as at this altitude the reduced partial pressure of oxygen in the cabin air has a limited
The new time zone
As far as the management of jet-lag itself is concerned the goal for those that intend to remain in the new time zone for many days is to achieve circadian realignment in the most rapid and efficient way possible, and to minimize symptoms during the interim period.1 However, there are limits to our knowledge and to what can be achieved. For instance, more information is required on the relationship between age and jet-lag, and frequent shifts to differing time zones, as with business
Emergence of chronobiotics?
The possibility that drugs could be developed that would accelerate resynchronization to a new time zone is a fascinating challenge to the clinical pharmacologist. As far as melatonin is concerned its sedative activity when endogenous levels are low is well documented, but clearly opinions differ as to its potential for chronobiotic activity.4, 5 After detailed deliberations, the United States Agency for Healthcare Research and Quality12 concluded that there was no evidence to suggest that
The way ahead
What then can be gleaned from these reviews concerning the present and future management of the fatigue and malaise associated with intercontinental journeys? Improvements in the cabin environment will depend on the aircraft industry and so, for the while, the approach of the healthy traveller must be to adopt the behavioural advice offered by the reviewers. Exposure to the light–dark cycle of a new time zone is advocated, though prescribed regimes involving artificial light may not, at
Conflicts of interest
None.
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Chest
(1988)
Cited by (5)
Occupational risk of organophosphates and other chemical and radiative exposure in the aircraft cabin: A systematic review
2021, Science of the Total EnvironmentCitation Excerpt :Increasingly, the field has become more focused on low-dose chronic exposure. To quote Nicholson (2009), “ Sub-clinical long-term effects cannot be completely ruled out, and whether contaminants in the air supply could be a factor in the malaise experienced by passengers remains uncertain.” Howard (2017) describes axonal transport damage caused by repeated low-dose exposure to OPs.
Air travel: Effects of sleep deprivation and jet lag
2013, ChestCitation Excerpt :Travel conditions within the airplane may contribute to some of the distress experienced by travelers (both travel fatigue and jet lag symptoms).31 For example, expansion of gas within the GI system (due to lowered cabin pressure) may result in discomfort/bloating, lower inspired oxygen may affect patients with respiratory conditions, motion sickness may present itself, and low relative humidity may result in dehydration, although the degree of dehydration is likely minimal.32 The diagnostic criteria for JLD are as follows: (1) there is a complaint of insomnia or excessive daytime sleepiness associated with transmeridian jet travel across at least two time zones; (2) there is associated impairment of daytime function, general malaise, or somatic symptoms such as gastrointestinal disturbance within 1 to 2 days after travel; and (3) the sleep disturbance is not better explained by another current sleep disorder, medical or neurologic disorder, mental disorder, medication use, or substance use disorder.33
Spatial orientation and disorientation
2017, The Neurosciences and the Practice of Aviation MedicineJet lag: Use of melatonin and melatonergic drugs
2014, Melatonin and Melatonergic Drugs in Clinical PracticeJet lag, circadian rhythm sleep disturbances, and depression: The role of melatonin and its analogs
2010, Advances in Therapy