Increase in volume of airline passenger traffic is leading to an increase in number of in-flight medical incidents [1, 2]. A large number of such incidents are, in fact, “identified, managed and documented by cabin crew without the involvement of medically trained persons” [3]. Common in-flight medical conditions are fainting or syncope (incidence 10-53.5%); gastrointestinal incidents like nausea, vomiting, diarrhea or flatus and bloating sensation (incidence 8-28%); and injuries (incidence 3-40%) [4, 5, 6].
A study by Mahony et al. reported “passenger medical incidents” after establishing “the reliability of cabin crew records” in an Oceania based airline [3]. This retrospective study from 1996 to 2004 evaluated a total of 11,326 incidents, using three round Delphi analysis [7]. There were 258.4 incidents per year (mean relative frequency) for 7.93 million passengers carried per year for 57.5 billion revenue passenger miles (paxmiles). Stated in another way, it was found that 159 incidents occurred per million passengers carried, equivalent to 113.3 incidents per million paxmiles. An interesting finding was that 14 (5%) of 276 aircraft diversion reported by the airline occurred due to passenger medical incidents during that period [3].
It was encouraging to note that except for 1359 (12%) incidents, the cabin crew handled the majority of incidents without medical assistance. Interestingly since 2000, this airline has a telemedicine provider for such incidents, and there too medical assistance was sought in case of 23 (1.7%) incidents only. Besides the likelihood of medical incidents being minor or self-correcting in nature, such statistics reflect highly on the preparedness and professional competence of the cabin crew. This is amply illustrated by 96% agreement (concordance [8]) for a matched sample of passenger medical incidents (n = 324) between “cabin crew records and those of medically trained persons” [3].
Various symptoms found in this cohort of passenger medical incidents, in order of relative frequencies, were [3]:-
- Unconscious: rapidly recovered – 41.1%
- Nausea/vomiting/diarrhoea – 19.5%
- Breathing difficulty – 15.9%
- Pain, without any other symptom – 5.0%
- Behavioural – 3.2%
- Injuries – 2.5%
- Chest pain – 2.3%
- Allergic/skin – 2.3%
- Unconscious: no recovery – 1.9%
- Unconscious: slow or delayed recovery – 1.5%
- Congested/fever – 1.2%
- Seizure – 1.1%
- Advice/undetermined – 1%
- Pregnant/in labour – <0.1% (n = 4)
Due to the nature of flight, it is likely be that “most frequent incidents are potentially associated with stresses of flight” [9], like “loss of consciousness may be associated by mild hypoxia and immobility” [1, 2, 10]. On the other hand, hyperventilation due to anxiety could be responsible for symptoms like shortness of breath or nausea and vomiting, particularly those cases which respond to reassurance and oxygen administration for short duration. Symptoms of pain were related to in-flight pressure changes, like toothache; or due to immobilization during flight leading to muscular or joint pains [3].
This study by Mahony et al. serves the vital purpose of providing the evidence base for first-aid training of the cabin crew, besides help modify “medical and first-aid kits to meet the changing needs” of the passengers [3].
Reference
1. Ruskin KJ. Hernanadez KA, Barash PG. Management of In-flight medical emergencies. Anaesthesiology 2008; 108: 749-55.
2. Silverman D, Gendreau M. Medical issues associated with commercial flights. Lancet 2009; 373: 2067-77.
4. DeJohn CA, Veronneau SJH, Wolbrink AM, Larcher JG, Smith DW, Garrett JS. An evaluation of the U.S. in-flight medical kit. Aviat Space Environ Med 2002; 73: 496-500.
5. Delaune EF, Lucas RH, Illig P. In-flight medical events and aircraft diversions: one airline’s experience. Aviat Space Environ Med 2003; 74: 62-8.
6. Lyznicki JM, Williams MA, Deitchman SD, Howe 3rd JP. Council on Scientific Affairs, American Medical Association: Inflight medical emergencies. Aviat Space Environ Med 2000; 71: 832-8.
8. Concordance correlation coefficient
9. Ruckman RF. ER in the skies. J Air Law Commerce 1999; 65: 77-123.
10. Bourell L, Turner MD. Management of In-flight medical emergencies. J Oral Maxillofac Surg 2010; 68: 1377-83.
Acknowledgement Image courtesy freedigitalphotos.net