Figures
- FIGURE 1
World Bank Data for numbers of passengers who travelled by air between 1970 and 2016. Reproduced from [4] with permission.
- FIGURE 2
Oxyhaemoglobin dissociation curve for healthy individuals and patients with chronic obstructive pulmonary disease (COPD) at high altitude. PO2: oxygen tension. Reproduced from [26] with permission.
- FIGURE 3
Pathophysiological changes in chronic obstructive pulmonary disease during air travel. PIO2: inspired oxygen tension; PAO2: alveolar oxygen tension; PaO2: arterial oxygen tension; PaCO2: arterial carbon dioxide tension; PEEP: positive end-expiratory pressure; RV: right ventricle.
- FIGURE 4
Algorithm for the assessment of fitness to fly in chronic obstructive pulmonary disease patients. LTOT: long-term oxygen therapy; PaO2: arterial oxygen tension; SpO2: arterial oxygen saturation measured by pulse oximetry; 6MWT: 6-min walk test. #: if dyspnoea on exertion, forced expiratory volume in 1 s <1.5 L or <30% predicted, a pre-existing requirement of oxygen/ventilatory support, bullous lung disease, comorbid conditions that may worsen hypoxaemia like cardiac disease and significant symptoms during previous air travel.
Tables
- TABLE 1
Studies comprising patients with chronic obstructive pulmonary disease (COPD) for prediction of hypoxaemia during air travel
Author [ref.] Year Patients Test/condition used Results Gong [33] 1984 22 moderate COPD HCT Sea level PaO2 predicted acute resting altitude PaO2 Dillard [51] 1989 18 severe COPD Hypobaric chamber Ground PaO2 correlated with expected altitude PaO2, combination of FEV1 and ground PaO2 improved prediction of PaO2 at 8000 ft Schwartz [52] 1984 13 severe COPD Inflight ABGs at 1650 m and 2250 m PaO2 measured <2 h before the flight in room air or a 17.2% oxygen mixture correlated with PaO2 at 1650 m. PaO2 measured several weeks before flight did not correlate with any in-flight measurements Berg [31] 1992 18 severe COPD Hypobaric chamber Oxygen supplementation via nasal cannula or Venturi mask corrects altitude hypoxaemia Christensen [30] 2000 15 severe COPD HCT Pre-flight PaO2 >70 mmHg, FEV1 or TLCO values do not predict altitude hypoxaemia. Light exercise may provoke hypoxaemia and there was a correlation between aerobic capacity and altitude PaO2 Robson [53] 2000 20 COPD (15 severe)
and 8 other RDHCT Altitude PaO2 could not be predicted from either FEV1 or pre-test SpO2 Seccombe [35] 2004 10 COPD and 15 ILD HCT with 50-m walk test Resting sea level PaO2 is poor for predicting the hypoxaemic response in both COPD and ILD groups. Means of PaO2 of both groups fell below recommended levels at both resting and when walking during HCT Akero [34] 2005 18 COPD In-flight ABG Significant desaturations were observed during flight, which were worsened with activity. A pre-flight PaO2 >70 mmHg did not predict in-flight hypoxaemia. Aerobic capacity showed the strongest correlation with in-flight PaO2 Chetta [54] 2007 15 COPD and 15 ILD HCT and 6MWT SpO2 in 6MWT can predict oxygen desaturation during HCT Kelly [55] 2008 13 severe COPD In-flight SpO2, post-flight HCT and 6MWT Significant desaturations were observed during flight, which were worsened with activity. HCT SpO2 was well correlated with in-flight SpO2. Resting PaO2 and the post-flight 6MWT result did not correlate with in-flight SpO2 Akero [50] 2008 100 COPD HCT Pre-flight SpO2 does not help to discriminate patients adequately for in-flight O2 supplementation. 30% of patients with pre-flight SpO2 >95% and 67% of patients with pre-flight SpO2 between 92–95% and without additional risk factors dropped PaO2 below 50 mmHg during HCT Robson [49] 2008 74 COPD and 44 other RD HCT Desaturation during HCT cannot be predicted reliably from either FEV1 or sea level SpO2. All patients with sea level SpO2 >95% maintained O2 saturation >90% during HCT. One-third of patients with sea level SpO2 between 92–95% and with no risk factor desaturated during HCT Kelly [56] 2009 18 severe COPD Mount Hutt (2086 m altitude) Ascent from sea level to altitude caused significant hypoxaemia (PaO2 75±9 versus 51±6 mmHg, respectively), and worsened during walk test (41±7 mmHg) which was partially reversed by supplemental oxygen (64±9 mmHg). KCO correlated both with resting altitude SaO2 and exercise PaO2 Edvardsen [57] 2012 100 severe COPD HCT and 6MWT An algorithm was constructed using a combination of resting and 6MWT SpO2. Resting SpO2 >95% combined with 6MWT SpO2 >84% had a sensitivity of 100% and specificity of 80% for fitness to fly Edvardsen [58] 2013 82 moderate-to-severe COPD HCT and pre- and post-flight symptom questionnaire Post-flight questionnaire results showed that there was no difference in HCT PaO2 between patients with and without symptoms; however, planned use of in-flight supplemental oxygen in patients with HCT PaO2 <50 mmHg resulted in a lower frequency of respiratory symptoms RD: respiratory disease; ILD: interstitial lung disease; HCT: hypoxic challenge test; ABG: arterial blood gas; 6MWT: 6-min walk test; SpO2: arterial oxygen saturation measured by pulse oximetry; PaO2: arterial oxygen tension; FEV1: forced expiratory volume in 1 s; TLCO: transfer factor of the lung for carbon monoxide; KCO: transfer coefficient of the lung for carbon monoxide.
- TABLE 2
Useful information websites for air travel
Organisation Website Contents Aerospace Medical Association www.asma.org Health tips for passengers and health professionals British Lung Foundation www.blf.org.uk Information and support website British Thoracic Society www.brit-thoracic.org.uk Patient information leaflet Centers for Disease Control wwwnc.cdc.gov/travel Travellers' health website for individuals and healthcare providers Civil Aviation Authority www.caa.co.uk/Passengers Medical information for passengers and healthcare providers European Lung Foundation www.europeanlung.org Information and medical tips for air travel European Federation of Allergy and Airways Diseases Patients' Associations www.efanet.org Enabling air travel with oxygen in Europe (an EFA booklet for patients with chronic respiratory disease); EFA booklet for steps for passengers flying with medical oxygen International Air Transport Association www.iata.org Medical manual for air travel International Civil Aviation Organization www.icao.int Manual of civil aviation medicine for flying personnel and healthcare providers International Society of Travel Medicine www.istm.org Online learning programmes for healthcare providers
Jump To
- Article
- Abstract
- Abstract
- Introduction
- General risk of flying
- The environment inside the aircraft: alterations in gas exchange and haemodynamics at high altitude
- The risk of flying with COPD
- Symptoms
- Assessment for in-flight hypoxaemia in COPD
- Tests used for pre-flight assessment
- How should COPD patients be prepared for flying?
- Oxygen supplementation
- Other problems
- Conclusion
- Footnotes
- References
- Figures & Data
- Info & Metrics