International Journal of Pediatrics
Volume 2018 (2018), Article ID 6596490, 8 pages
https://doi.org/10.1155/2018/6596490

Review Article

A Systematic Review of Pediatric and Adult In-Flight Medical Emergencies

Christina Sul¹ and Sherif M. Badawy1,2

¹Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
²Division of Hematology, Oncology and Stem Cell Transplant, Ann & Robert H. Lurie Children’s Hospital, Chicago, Illinois, USA

Correspondence should be addressed to Sherif M. Badawy; sbadawy@luriechildrens.org

Received 21 July 2018; Accepted 24 October 2018; Published 25 November 2018

Academic Editor: Han-Ping Wu

Copyright © 2018 Christina Sul and Sherif M. Badawy. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract.

In-flight medical emergencies (IMEs) are acute onboard events of illnesses or injuries with potential immediate risk to a passenger’s short- or long-term health, or life. IMEs are significant events that are related to public safety concerns. With the increasing amount of annual air travel every year, it is expected that the number of encountered IMEs will continue to grow. Thus, it will be critical to develop and implement appropriate measures to manage IMEs with the best possible outcome. Despite the fact that most IMEs are self-limited with no serious adverse events, serious IME can lead to death, disability, or other unfavorable health outcomes, particularly as a result of suboptimal medical care. In this article, we systematically reviewed the published up-to-date evidence on the subject of in-flight emergencies with a specific focus on pediatric population.

1. Introduction

Almost 4 billion passengers fly worldwide each year on commercial airlines [1]. While the medical field looks to aviation for key concepts of quality control and safety, ironically medical emergencies that occur on board of commercial aircraft are often chaotic events compounded by noise and vibration, limited space, lack of privacy, and language barriers. It is estimated that approximately 44,000 in-flight medical emergencies occur worldwide annually [2, 3], a number likely to increase as more passengers travel by air each year. In-flight medical emergencies (IME) are rare events; however when they do occur, access to medical care is limited by the distance to a nearest medical center, contents of an emergency medical kit, training of the onboard personnel, and availability of medically trained volunteers among other factors. Further, lack of standardized reporting of IMEs makes it difficult to perform epidemiologic research to identify areas for improvement. With increasing number of travelers overall, pediatric passenger population is also increasing; however very little is known about pediatric IMEs. Despite comprising almost 10% of the IMEs, there are only two studies to date that have been dedicated solely to pediatric IMEs [4, 5]. Our objective was to systematically review the published most recent evidence on the subject of in-flight emergencies with a specific focus on pediatric population.

2. Methods

2.1. Literature Search

This systematic review covered literature published until 2018 with no language limits. The search strategy looked for all articles on in-flight medical emergencies. We searched MEDLINE (through PubMed) from inception to May 15, 2018. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in the reporting of evidence across the studies reviewed herein [6]. Two independent reviewers (CS and SMB) assessed abstracts and articles against the eligibility criteria. Disagreements were resolved by discussion.

2.2. Eligibility Criteria

Eligible studies were original research articles, medical emergencies occurring while in-flight and on board of commercial aircraft, and articles that included pediatric patients from the analysis. We excluded studies that focused on medical education, telemedicine techniques for air-to-ground data transmission, role of medical volunteers in flight diversion decision-making, and in-airport medical emergencies.

2.3. Data Synthesis

We used a standardized form for data extraction. Data items in the extraction form included the following: first author’s name; publication year; country; aim of the study; data source; participants’ age and sex; study design and setting; sample size; selection criteria; and follow-up.

3. Results

3.1. Literature Search

A total of 170 articles were identified and retrieved. Two authors (CS and SB) independently screened the article titles and abstracts. A total of 33 records met the predefined inclusion criteria. Two authors (CS and SB) then independently reviewed the full text of these articles in detail against the exclusion criteria, and 8 items were excluded. A total of 25 articles met the predefined criteria to be included with only two articles that focused solely on pediatric in-flight emergencies. We did not identify any non-English articles that met our inclusion criteria. The selection process and reason of excluding full-text publications are outlined in an adapted PRISMA study flowchart (Figure 1) [6].

Figure 1: Flow of studies through the review according to the PRISMA guidelines.

3.2. Study Characteristics

While our search identified articles published prior to 1980s, only articles published in 1989 and after met the predefined inclusion criteria; 4 out of 28 included studies that were published in 1989, 1 in 1990s, 14 in 2000s, and 9 in the current decade. Over half of the included studies have been performed in the United States (in whole or in part), 13/25 [2–5, 7–15], 4 in Germany [16–19], 3 in UK [20–22], 1 form Australia [23], 1 in Canada [24], 1 from China [25], 1 from France [26], and 1 in Turkey [27]. Most studies focused on characterizing IMEs on commercial aircraft. Collected and reported data commonly included patients’ demographic information, type of medical or surgical complaint, utilization of the medical kits, presence of medical volunteers, and rates of diversion of the aircraft. Few studies have focused on a specific subset of patient population such as pediatric [4, 5], neurologic [15], and psychiatric [7]. 12 out of 25 included studies reporting data on both pediatric and adult patients [2, 3, 7–10, 16, 17, 20, 25–27]; ten studies either did not specify the age range of the patients’ whose records were analyzed or did not include data on age altogether [11–15, 18, 21–24]; for these studies the population column in Table 1 is marked as unknown. Two articles explored pediatric-only in-flight emergencies [4, 5]. Age data was not applicable for reporting in one study; thus the population column in Table 1 is marked as N/A [19]. Overwhelming majority of the included studies are retrospective reviews that obtained data from either medical records directly reported by the commercial airlines [10, 13, 14, 17–19, 22, 23, 27], medical records kept by the airports and nearby emergency rooms and hospitals [8, 9, 14], or records collected by the air-to-ground medical support broadly categorized as telemedicine services [2–5, 7, 11, 12, 15, 20, 21, 24–26]. Two studies obtained all or part of data from questionnaires [14, 16]. Sample size ranged from 10 to 11,920, with a median of 424 and mean of 1,750 records reviewed.

Table 1: Summary of included studies that focused on in-flight medical emergencies.

Source (country)
Purpose of the study
Study design
Population
Age, sex
Group (n)
Source of data
Duration

Moore et al. (USA)
To determine the incidence and character of pediatric emergencies on commercial airline and to evaluate current in-flight medical kits.
Observational retrospective review
Pediatric
Mean patient age
6.8 years,
Sex unknown
222
Telemedicine database
7 years

Rotta et al. (USA)
To characterize in-flight pediatric fatalities onboard commercial airlines
Retrospective cohort study
Pediatric
Median patient age 3.5 months
(range 1mo-15 yrs)
Female 50%
10
Telemedicine database
3.5 years

Hinkelbein et al. (Germany)
To gather data on incidence, nature, and medical equipment use for in-flight emergencies
Retrospective analysis of secondary data (survey)
Adult and Pediatric
Mean patient age 54.1 years
(range 15-79 yrs)
Female 40.7%
54
Physician members of an aerospace medical society
1 month

Szmajer et al. (France)
To analyze the causes and outcomes of in-flight emergency calls from a commercial airline
Retrospective study
Adult and Pediatric
Mean patient age 41.12 years
(range 1- 84 yrs)
Female 37.7%
380
Telemedicine database
1 year

Matsumoto et al. (USA)
To ascertain the incidence of in-flight psychiatric emergencies, their associated factors, and outcomes.
Retrospective study
Adult and Pediatric
Mean patient age
39.6 years
(range 10- 80 yrs)
Female 73%
1,375
Telemedicine database
1 year

Kesapli et al. (Turkey)
To evaluate the incidence and status of urgent medical conditions, the attitudes of health professionals, the adequacy of medical kits and training of cabin crew
Retrospective cohort study
Adult and Pediatric
Median patient age 45 years
(range 0- >=86 yrs)
Female 53.2%
1,312
Commercial airline database
3 years

Peterson et al. (USA)
To describe in-flight medical emergencies and the outcomes of these events.
Retrospective cohort study
Adult and Pediatric
Mean patient age
48 years
(range 14 days-100 yrs)
Sex unknown
11,920
Telemedicine database
2.8 years

Weinlich et al. (Germany)
To identify which patients require diversion due to a medical incident on a commercial flight
Prospective study
Adult and Pediatric
Mean patient age
58 years
(range <1 – 91 yrs)
Sex unknown
3,364
Commercial airline database
3 years

Urwin et al. (UK)
To characterize medical emergencies on board of commercial flights
Retrospective review
Adult and Pediatric
Mean patient age
42 years
(range 1- 87 yrs)
Female 56%
273
Telemedicine database
5 years

Chan et al. (USA)
To determine incidence, post-flight treatments, outcomes, morbidity, and mortality of in-flight medical emergencies
Retrospective study
Adult and Pediatric
Mean patient age
46.6 years
Female 54.7%
744
EMS, ED, and inpatient hospital records of in-flight medical emergencies from a major international airport
1 year

Speizer et al. (USA)
To evaluate the potential usefulness of any emergency medical kit
Retrospective study
Adult and Pediatric
Age unknown
Female 50.8%
260
ER, hospital, airport first-aid station medical records
6 months

Delaune et al. (USA)
To determine the incidence of each type of in-flight medical complaint, the appropriateness of medical kit contents, which factors lead to aircraft diversion, and which factors affect the appropriateness of the decision to divert
Observational retrospective review
Adult and Pediatric
Not reported
2,279
Telemedicine database
1 year

Baltsezak (China)
To characterize medical emergencies on board of commercial flights
Retrospective study
Adult and Pediatric
Not reported
191
Telemedicine database
1 year

Hordinsky (USA)
To characterize in-flight medical emergencies and efficacy of medical kit usage
Retrospective review
Adult and Pediatric
Not reported
1,016
Commercial airline database
1 year

Alves et al. (USA)
To gather data on outcomes and prognostic factors for victims of in-flight cardiac arrest
Retrospective cohort study
Adult
Mean patient age 61.9 years
(SD 15.62)
Female 36.5%
394
Telemedicine database
10 years

Brown et al. (USA)
To describe the characteristics and outcomes of AED use during in-flight emergencies
Retrospective descriptive study
Adult
Mean patient age
58 years
Female 36%
169
Telemedicine database
4.7 years

Hung et al. (UK)
To provide description of in-flight medical emergencies and systematically examine predictors of medical flight diversions and deaths
Retrospective cohort study
Adult
Age unknown,
Female 53.9%
4,068
Telemedicine database
5 years

Page et al. (USA)
To analyze the AED use on board of a commercial flight
Retrospective cohort study
Adult
Mean patient age
58 years
Female 34%
200
Commercial airline database
2 years

Cottrell et al. (USA)
To analyze the effectiveness of enhanced medical kit in treating in-flight emergencies on board of a commercial flight
Retrospective review and survey study
Adult
Mean patient age
54 years (males)
48 years (females)
Female 43%
362
Commercial airline database, hospital records, and patient and health care providers questionnaires
1 year

Valani et al. (Canada)
To determine the causes of in-flight medical diversions from a commercial airline
Retrospective review
Not reported
Not reported
220
Telemedicine and commercial airline databases
5 years

Quereshi et al. (UK)
To analyze medical emergencies on board of single commercial airline
Retrospective review
Not reported
Not reported
507
Commercial airline database
6 months

Sirven et al. (USA)
To analyze the frequency of neurologic events during commercial airline flights and to assess whether onboard emergency medical kits are adequate for such events
Retrospective study
Not reported
Not reported
2,042
Telemedicine database
5 years

Donaldson et al. (Australia)
To analyze the types of medical emergencies encountered during commercial air travel
Retrospective study
Not reported
Not reported
454
Commercial airline database
1 year

Sand et al. (Germany)
To document medically relevant emergencies in airline passengers
Retrospective study
Unknown
Unknown
10,189
Commercial airline database
6 years

Sand et al. (Germany)
To analyze different forms of documentation for in-flight medical emergencies use by commercial airlines
Documentation analysis
N/A
N/A
10 airlines
In-flight medical emergency documentation forms from commercial airlines
Unknown

3.3. Characteristics of Pediatric In-Flight Emergencies

Rotta et al. reported that pediatric IMEs comprise 9.3% of all in-flight emergencies or 2.24 events per 1 million passengers [4]. This number is close to 12.04% reported by Baltsezak et al. [25], 9.15% reported by Moore et al. [5], and 9% reported by Weinlich et al. [17]. Average age for pediatric in-flight emergency patient was 6.8 years reported by Moore et al. [5] and 7.3 years reported by Weinlich et al. [17]. Median age for a pediatric patient suffering a fatal event on board of commercial aircraft was 3.5 months [4]. The most common pediatric medical complains were infectious (27%), neurological (15%), and respiratory (13%) [5]. Weinlich et al. reported similar findings where infectious disease comprised 28% of pediatric in-flight emergencies, epilepsy (7%), and respiratory problems (4%) [17]. Emergency medical kit was used in 27% of pediatric in-flight emergencies, with antipyretics being the most commonly administered medication [5]. Automated external defibrillator (AED) was applied in 4 out of 10 pediatric in-flight fatalities; none of the four cases were found to have an indication for a shock [4]. In the study exploring telemedicine service for IMEs, Urwin et al. reported that the fewest air-to-ground calls were received for children 5 years and under, with only 5% calls taken for this age group [20].

3.4. Reporting of In-Flight Medical Emergencies

Sand et al. reported that after querying 32 commercial airlines for medical flight reports, only four (12.5%) were able to provide the required data [18]. From the included 25 studies, 6 (24%) have mentioned lack of industry-wide standardized reporting system as a factor limiting the ability to effectively access and analyze data on IMEs [3, 10, 16, 18–20].

4. Discussion

As the number of passengers who travel by air continues to grow, so does the incidence of IMEs. Additionally longer flight duration exposes passengers to physiologic stressors such as relative hypoxia and decreased humidity of circulating air [28]. Based on the reported data, pediatric in-flight emergencies comprise approximately 9.9% of all IMEs. Pediatric conditions that lead to diversions are neurological (due to seizures) and respiratory (due to asthma) [5], prompting a careful consideration of inclusion in emergency medical kits the weight-based seizure-aborting agents [15] and bronchodilators that can be effectively administered to young children [14]. Even when bronchodilator is available in a medical kit, the absence of appropriate delivery mechanism such as nebulizer machine or a valved holding chamber, also referred to as a spacer, makes delivery of aerosolized bronchodilator inefficient in young children [29, 30]. Presence of the nebulized bronchodilator may not be necessary on board of the aircraft as evidence has shown no significant benefit in use of the nebulizer over a metered dose inhaler (MDI) with spacer; however presence of a spacer device and appropriately sized mask is crucial to the effective delivery of the bronchodilator to the lungs [31]. Half of the passengers with respiratory symptoms suffered from an asthma exacerbation, and a third of the patients suffering an asthma attack have forgotten to bring their medication on board of the aircraft [22]. Thus, for example, a verbal or written reminder during the baggage check-in and drop-off process could be a useful tool to reduce the risk of forgetting to bring the medications on board. Further, bag-mask ventilation is a safe and effective lifesaving intervention for patients who experience critical cardiorespiratory events and require short-term ventilation support. Nevertheless, for bag-mask ventilation to be effective, the mask needs to be with the right size with the airway maintained in the optimum position and tight seal is secured around mouth and nose for effective ventilation. Although medical flight kits (MFKs) usually include bag-masks, they are usually adult-sized, making bag-mask ventilation for infants and young children not possible, if not harmful with over ventilation. So, without the right age and size-appropriate equipment onboard, available healthcare providers may not be able to provide the best case possible in these IMEs situations.

Rotta et al. focused on pediatric fatalities on board of commercial aircraft. They reported that 6 out of 10 (60%) patients suffering in-flight death did not have any preexisting medical conditions and 9 out 10 (90%) were patients under the age of 2 years, so called lap infants. Their study revealed a previously unrecognized vulnerable group of children under 2 years who share seating and/or sleeping arrangement with a potentially fatigued adult during long haul flights. Therefore, it may be helpful to have dedicated age-appropriate seats for infants under 2 years old, similar to car seats concepts, though that would come with extra cost for families.

Not enough data is available to draw objective conclusions for AED use in pediatric IMEs. However, data in adult population strongly supports presence of AED on board of commercial aircraft [13, 32]. AED use was a factor most strongly associated with diversion [2], and an installment of AEDs on a commercial aircraft has been found to be cost-effective by the conventional standards of cost-effectiveness [33].

Aside from defibrillator, the contents of the emergency medical kits are mainly determined by the consensus opinion of different airlines rather than evidence. Thus an opportunity exists to study and develop evidence-based emergency medical kits. The contents of MFKs vary significantly across different airlines, and some airlines were found to be poorly equipped to manage IMEs. While MFKs usually contain bag-masks, these are often adult-sized masks only, limiting the benefits of bag-mask ventilation for infants and children during IMEs. Given that IMEs are more likely to happen during the long haul flights, even with timely diversion, and that the arrival to a ground emergency care facility may be significantly delayed, expanding the contents of the MFKs to be suitable for Trans-Atlantic and Trans-Pacific flights is worth considering.

Further, the commercial air travel industry lacks a standardized industry-wide approach to reporting IMEs. Sand et al. argue that this lack of standardization in reporting hampers epidemiologic research [18, 19]. This notion is supported by multiple other articles included in this review [3, 10, 16, 20]. Epidemiologic research of in-flight emergencies is necessary to establish preflight screening guidelines, standardize the contents of the emergency medical kit, establish guidance for air-to-ground medical consultation, and standardize reporting of IMEs.

Our systematic review has a few strengths. First, we followed the recommendations for rigorous systematic review methodology [6, 34–37]. Second, we conducted a review with a prespecified search strategy and no language restrictions so as to minimize publication bias and identify the largest possible number of relevant studies. Third, 2 authors completed the review process independently at all stages of the systematic review. Our systematic review has two possible methodological limitations. First, similar to other systematic literature reviews, it is possible that we could have missed few relevant articles. Second, to identify the strongest most up-to-date available evidence, we included articles that were published in peer-reviewed journals, which could have introduced publication bias [38, 39].

5. Conclusions

IMEs are significant events that are related to public safety concerns. There is wide variability in the available services, expertise, and supplies required for the optimal management of infants and children with different IMEs. Additional help or access to resources needed onboard is often limited, which makes the situation of pediatric IMEs more complex. Having an enhanced MFK onboard could benefit pediatric patients with IMEs, particularly infants and young children, which could lead to less frequent flight diversions of flights and might have some cost benefit to airlines as well. Most flight crewmembers and staff are trained in first aid and basic life support, but lack skills needed for pediatric emergencies. This lack of preparedness further highlights the challenge of managing pediatric IME. Given the lack of standard reporting of IMEs, the problem of IMEs could be more significant since the currently used methods may have underestimated the true incidence and burden of IMEs. Central registries and documentation protocols are warranted to facilitate aeromedical research of IMEs. Well-equipped MFKs should be available in all commercial airlines onboard to optimize the management of IMEs, particularly pediatric ones. Standard regulations on the content of MFKs, supported by national and international authorities and organizations, are essential to ensure passenger safety, in particular for infants and young children.

Disclosure

The content is solely the responsibility of the authors and does not necessarily represent the official views of the Agency for Healthcare Research and Quality.

Conflicts of Interest

The authors declare that they have no conflicts of interest.

Acknowledgments

Sherif M. Badawy was supported by grant number K12HS023011 from the Agency for Healthcare Research and Quality.

References

“The World Bank Airtransport, passengers carried,” https://data.worldbank.org/indicator/IS.AIR.PSGR.

D. C. Peterson, C. Martin-Gill, F. X. Guyette et al., “Outcomes of medical emergencies on commercial airline flights,” The New England Journal of Medicine, vol. 368, no. 22, pp. 2075–2083, 2013.

E. F. Delaune, R. H. Lucas, and P. Illig, “In-flight medical events and aircraft diversions: One airline's experience,” Aviation, Space, and Environmental Medicine, vol. 74, no. 1, pp. 62–68, 2003.

A. T. Rotta, P. M. Alves, K. E. Mason et al., “Fatalities above 30,000 feet: Characterizing pediatric deaths on commercial airline flights worldwide,” Pediatric Critical Care Medicine, vol. 15, no. 8, pp. e360–e363, 2014.

B. R. Moore, J. M. Ping, and D. W. Claypool, “Pediatric emergencies on a US-based commercial airline,” Pediatric Emergency Care, vol. 21, no. 11, pp. 725–729, 2005.

L. Shamseer, D. Moher, M. Clarke et al., “Preferred reporting items for systematic review and meta-analysis protocols (prisma-p) 2015: Elaboration and explanation,” British Medical Journal, vol. 349, Article ID g7647, 2015.

K. Matsumoto and D. Goebert, “In-flight psychiatric emergencies,” Aviation, Space, and Environmental Medicine, vol. 72, no. 10, pp. 919–923, 2001.

S. B. Chan, T. M. Hogan, and J. C. Silva, “Medical emergencies at a major international airport: in-flight symptoms and ground-based follow-up,” Aviation Space and Environmental Medicine, vol. 73, no. 10, pp. 1021–1024, 2002.

C. Speizer, C. J. Rennie, and H. Breton, “Prevalence of in-flight medical emergencies on commercial airlines,” Annals of Emergency Medicine, vol. 18, no. 1, pp. 26–29, 1989.

J. R. Hordinsky and M. H. George, “Response capability during civil air carrier inflight medical emergencies,” Aviation, Space, and Environmental Medicine, vol. 60, no. 12, pp. 1211–1214, 1989.

P. M. Alves, C. A. DeJohn, E. M. Ricaurte, and W. D. Mills, “Prognostic factors for outcomes of in-flight sudden cardiac arrest on commercial airlines,” Aerospace Medicine and Human Performance, vol. 87, no. 10, pp. 862–868, 2016.

A. M. Brown, J. C. Rittenberger, C. M. Ammon, S. Harrington, and F. X. Guyette, “In-flight automated external defibrillator use and consultation patterns,” Prehospital Emergency Care, vol. 14, no. 2, pp. 235–239, 2010.

R. L Page, J. A. Joglar, R. C. Kowal et al., “Use of automated external defibrillators by a U.S. airline,” New England Journal of Medicine, vol. 343, no. 17, pp. 1210–1216, 2000.

J. J. Cottrell, J. T. Callaghan, G. M. Kohn, E. C. Hensler, and R. M. Rogers, “In-flight Medical Emergencies: One Year of Experience With the Enhanced Medical Kit,” Journal of the American Medical Association, vol. 262, no. 12, pp. 1653–1656, 1989.

J. I. Sirven, D. W. Claypool, K. L. Sahs et al., “Is there a neurologist on this flight?” Neurology, vol. 58, no. 12, pp. 1739–1744, 2002.

J. Hinkelbein, C. Neuhaus, L. Böhm, S. Kalina, and S. Braunecker, “In-flight medical emergencies during airline operations: A survey of physicians on the incidence, nature, and available medical equipment,” Open Access Emergency Medicine, vol. 9, pp. 31–35, 2017.

M. Weinlich, N. Nieuwkamp, U. Stueben, I. Marzi, and F. Walcher, “Telemedical assistance for in-flight emergencies on intercontinental commercial aircraft,” Journal of Telemedicine and Telecare, vol. 15, no. 8, pp. 409–413, 2009.

M. Sand, F.-G. Bechara, D. Sand, and B. Mann, “Surgical and medical emergencies on board European aircraft: A retrospective study of 10189 cases,” Critical Care, vol. 13, no. 1, 2009.

M. Sand, S. Morrosch, D. Sand, P. Altmeyer, and F. G. Bechara, “Medical emergencies on board commercial airlines: is documentation as expected?” Critical Care, vol. 16, no. 2, p. R42, 2012.

A. Urwin, J. Ferguson, R. McDonald, and S. Fraser, “A five-year review of ground-to-air emergency medical advice,” Journal of Telemedicine and Telecare, vol. 14, no. 3, pp. 157–159, 2008.

K. K. Hung, E. Y. Chan, R. A. Cocks, R. M. Ong, T. H. Rainer, and C. A. Graham, “Predictors of flight diversions and deaths for in-flight medical emergencies in commercial aviation,” JAMA Internal Medicine, vol. 170, no. 15, pp. 1401-1402, 2010.

A. Qureshi and K. M. Porter, “Emergencies in the air,” Emergency Medicine Journal, vol. 22, no. 9, pp. 658-659, 2005.

E. Donaldson and J. Pearnt, “First Aid in the Air,” ANZ Journal of Surgery, vol. 66, no. 7, pp. 431–434, 1996.

R. Valani, M. Cornacchia, and D. Kube, “Flight diversions due to onboard medical emergencies on an international commercial airline,” Aviation, Space, and Environmental Medicine, vol. 81, no. 11, pp. 1037–1040, 2010.

S. Baltsezak, “Clinic in the air? A retrospective study of medical emergency calls from a major international airline,” Journal of Travel Medicine, vol. 15, no. 6, pp. 391–394, 2008.

M. Szmajer, P. Rodriguez, P. Sauval, M.-P. Charetteur, A. Derossi, and P. Carli, “Medical assistance during commercial airline flights: Analysis of 11 years experience of the Paris emergency medical service (SAMU) between 1989 and 1999,” Resuscitation, vol. 50, no. 2, pp. 147–151, 2001.

M. Kesapli, C. Akyol, F. Gungor, A. J. Akyol, D. S. Guven, and G. Kaya, “Inflight Emergencies during Eurasian Flights,” Journal of Travel Medicine, vol. 22, no. 6, pp. 361–367, 2015.

B. Shepherd, D. Macpherson, and C. M. B. Edwards, “In-flight emergencies: Playing The Good Samaritan,” Journal of the Royal Society of Medicine, vol. 99, no. 12, pp. 628–631, 2006.

R. C. Ahrens, “The role of the MDI and DPI in pediatric patients: “Children are not just miniature adults”,” Respiratory Care, vol. 50, no. 10, pp. 1323–1328, 2005.

S. M. Badawy, A. A. Thompson, and M. Sand, “In-flight emergencies: medical kits are not good enough for kids,” Journal of Paediatrics and Child Health, vol. 52, no. 4, pp. 363–365, 2016.

N. Mitselou, G. Hedlin, and C.-A. Hederos, “Spacers versus nebulizers in treatment of acute asthma – a prospective randomized study in preschool children,” Journal of Asthma & Allergy Educators, vol. 53, no. 10, pp. 1059–1062, 2016.

R. O. Cummins and J. A. Schubach, “Frequency and Types of Medical Emergencies Among Commercial Air Travelers,” Journal of the American Medical Association, vol. 261, no. 9, pp. 1295–1299, 1989.

P. W. Groeneveld, “Cost-effectiveness of Automated External Defibrillators on Airlines,” Journal of the American Medical Association, vol. 286, no. 12, p. 1482, 2001.

D. Moher, A. Liberati, and J. Tetzlaff, “Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement,” Journal of Clinical Epidemiology, vol. 62, no. 10, pp. 1006–1012, 2009.

J. Higgins and S. Green, “Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0,” in The Cochrane Collaboration, 2011, http://www.cochrane-handbook.org.

E. Tacconelli, “Systematic Reviews: CRD’s Guidance for Undertaking Reviews in Health Care,” in The Lancet Infectious Diseases, vol. 10, p. 226, University of York, Centre for Reviews and Dissemination, York, UK, 2010.

D. Moher, L. Shamseer, and M. Clarke, “Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement,” Systematic Reviews, vol. 4, no. 1, article 1, 2015.

H.-H. Dubben and H.-P. Beck-Bornholdt, “Systematic review of publication bias in studies on publication bias,” British Medical Journal, vol. 331, no. 7514, pp. 433-434, 2005.

AA. Bartolucci and WB. Hillegass, “Overview, strengths, and limitations of systematic reviews and meta-analyses,” in Evidence-Based Practice: Toward Optimizing Clinical Outcomes, F. Chiappelli, X. M. Caldeira, N. Neagos, O. O. Oluwadara, M. H. Ramchandani, and O. O. Ramchandani MH, Eds., pp. 17–34, Springer, Berlin, Germany, 2010.