Evidence-Based Medicine, inflight-emergencies, and the responsibility of airlines

By Prathap Tharyan

Posted on October 3, 2011

Akshay Sharma, in a courageous first person account in the National Medical Journal of India, details his experience of dealing with a medical emergency in a four year old child who was unresponsive and dehydrated due to  repeated vomiting after a pre-boarding airport snack, while on a trans-Atlantic flight 30,000 feet above sea level.¹
As an itinerant traveler, and having been caught in similar predicaments, I commend Akshay for his courage in responding to the medical emergency and upholding the integrity and ideals of the medical profession so far removed  from the safe confines of a well-equipped hospital. 
I also admire his candor in admitting his initial reluctance to get involved in a potentially critical situation, fraught as it was with potential medico-legal implications and the possibility of public embarrassment. 
In the real world, heroic acts are often spawned from fear or compulsion, but completion of the act in the manner that Akshay did, in taking a carefully considered decision that led to the safe recovery of the ill child, speaks of quiet confidence in his own abilities and awareness of his limitations, given the constraints imposed by his situation, and his level of experience as an intern in training. 


Was Akshay’s response “evidence-based”?

Akshay suggests that his action, of securing intravenous access and providing intravenous fluids to the child contrary to the advice provided by the Medilink ground team contacted by the aircrew by tele-link to initially try a conservative approach, was not “evidence-based”. 
I submit that this is not necessarily true and is based on a common mis-perception that evidence-based medicine only concerns the incorporation of external evidence (ideally from systematic reviews of interventional trials) as the sole basis for medical interventions. 
The true linchpin of Evidence-Based Medicine, or more appropriately “Evidence-Informed Healthcare” is the astute clinician who has the skills to rapidly and accurately diagnose the clinical condition and consider prognostic issues; the expertise to access and interpret the reliability of the best available evidence; and to assess the applicability of the evidence within the context and constraints of healthcare provision. The wishes of the patient and his or her family would also be important, ²though less pressingly so in a medical emergency.³

In his report Askhay demonstrated all the essential attributes of evidence-informed health decision making byassessing various interventional options based on the uncertain probability (unstated in the report) of oral promethazine acting rapidly enough to prevent further vomiting, worsening dehydration, and leading to a situation where securing intravenous access in the four-year old could pose difficulties. 

In clinical situations, particularly in emergencies, one tends to use Bayesian logic based on one’s assessment of multiple parameters, their probabilities of occurrence, and the likelihood of success with different interventions to decide on options, rather than the more linear approach often followed in classical evidence-based medical teaching. 


In-flight emergencies and the availability of adequate medical cover

What might have reassured Akshay in this crisis was the opportunity to discuss his reasoning and to have this approved by the Medlink ground team. This facility is not always available on all airlines. 
In the three instances I was reluctantly thrust in to responding to in-flight emergencies, fellow “medical” passengers turned out to be laboratory personnel, or those who pleaded inexperience, leaving me, a psychiatrist, to deal with the emergencies! Fortunately the emergencies were self-limiting.


The good, the not so good, and the plain ugly facts about in-flight emergencies

The first involved food poisoning in an adult that settled with conservative management; the second an epileptic seizure in an adult on a transatlantic flight caused by sleep deprivation and irregular anti-epileptic medication that required only masterly inactivity and advancement of the scheduled antiepileptic dose. In the third,an unresponsive elderly gentleman came around from a syncope after a few minutes of ensuring airway patency with an Ambu-bag. 

In all three situations, the aircrew did not have access to more experienced help. They also seemed uncomfortable with my abilities to deal with the situation when my interventions were not immediately successful, since I had declared I was a psychiatrist. 
In all three instances, my internal turmoil was inversely proportional to my external calm and sense of control I endeavored to convey, while silently issuing volleys of prayers for divine intervention and hoping the height we were at would ensure better communication with the Almighty. 
In all three situations, I too, like Akshay, was a reluctant ‘volunteer”, whose decision to volunteer was taken for me by nosy, but well-meaning, co-passengers who had “discovered” my profession and sought free medical advice for their ailments,at the expense of my forfeiting the privilege of settling down to watch in-flight movies with some liquid refreshments! 
Also in all three instances, the aircrew rewarded my contributions by bumping me up to business class, or providing me with voucher upgrades, or by a long chat with a charming air-hostess!

A more disastrous outcome occurred in Mumbai airport in 2002, when on arrival from a tiring overseas trip, and while awaiting a domestic transit flight, a middle aged gentleman dropped unconscious with a cardiac arrest in the transit terminal at around three am. A fellow passenger and I attempted cardiopulmonary resuscitation unsuccessfully and gave up after 25-30 minutes. There were no medical facilities or medical emergency equipment that we could access on site, and emergency medical personnel summoned arrived too late to do any good. 

The responsibility of airlines

The next time you take a long-haul flight, it might be prudent to enquire to the readiness of your chosen airline to deal with in-flight medical emergencies. 
In today’s world of increasing global travel, airlines and airports that rely on the fortuitous presence in their passenger lists of trained medical personnel willing to help in emergencies, and with the competence to do so, is simply not good enough. 

Airlines need to ensure that their aircrews are adequately trained to deal with medical emergencies, the relevant emergency equipment and supplies are on board, evidence-based emergency manuals are available for reference, and tele-links to emergency medical help are routinely available. 

Passengers should be provided with precautions to be followed to prevent medical mishaps on long-haul flights, and the facilities available to deal with them, should they occur. 

Medically trained passengers who are willing to help in medical emergencies could be identified a-priori, or at the time of booking tickets, and provided with additional training and information about emergency equipment available on board. They could be provided frequent flyer benefits for enrollment and for services rendered, as these are not considered as compensation.⁵

All airports should have emergency help available round the clock, response times checked, contact numbers prominently displayed and clinical audits undertaken on adequacy of responses, response times, and outcomes. 

Finally, the institution of these measures, and additional ones, on the reduction in undesirable outcomes after in-flight and in-transit medical emergencies should be properly evaluated, and a common registry created. 

This issue is clearly topical and some other suggestions that airlines ought to follow to deal with in-flight emergencies are provide in a recent JAMA article.⁴

Emergency measure for those responding to in-flight emergencies to institute in particular emergencies are detailed in a Lancet report.⁵


What is the evidence regarding managing in-flight emergencies?
I could not find a Cochrane Systematic review in The Cochrane Library on “Interventions to prevent adverse outcomes during in-flight or in-transit medical emergencies”. 
There is a Cochrane systematic review on the use of “Compression stockings for preventing deep-vein thrombosis in airline passengers”, ⁶and another on, “Melatonin for the prevention and treatment of jet lag”.⁷ Both interventions are recommended by the reviews.
There are possibly other systematic reviews dealing with individual medical emergencies on long-haul flights in The Cochrane Library, and it would help if the publishers could also provide a collection of reviews pertaining to travel medicine in addition to the current collections they display on their home page.


Not a one-off event
As an aside, Akshay Sharma is one of the founding members of Informer, an initiative of medical students that seek to improve the ability of medical students to understand, and to contribute to, research. Akshay is also one of the guiding lights behind the Cochrane Student’s Journal Club. 
If more of “tomorrow’s doctors” display the kind of initiative and enthusiasm towards the medical profession and the use of reliable evidence that Akshay and his young colleagues do, then the rest of us can rest easy that the ideals of our profession will be nurtured and health outcomes improved; and also enjoy more fully the benefits of international air travel. 

References:

1. Sharma A. In the air. National Medical Journal of India 2011;24(4):231-2. 
2. Straus, S., Richardson, W.S., Glasziou, P. & Haynes, R.B. (2005). Evidence-based medicine: How to practice and teach EBM (3rd ed.). Edinburgh: Churchill Livingstone.4th Ed.: 2011
3.  Roberts I, Prieto-Merino D, Shakur H, Chalmers I, Nicholl J. Effect of consent rituals on mortality in emergency care research. Lancet. 2011;377(9771):1071-2.
4. Mattison ML, Zeidel M. Navigating the challenges of in-flight emergencies. JAMA. 2011;305(19):2003-4.
5. Silverman D, Gendreau M. Medical issues associated with commercial flights. Lancet. 2009;373(9680):2067-77.
6. Clarke MJ, Hopewell S, Juszczak E, Eisinga A, Kjeldstrøm M. Compression stockings for preventing deep vein thrombosis in airline passengers. Cochrane Database of Systematic Reviews 2006, Issue 2. Art. No.: CD004002. DOI: 10.1002/14651858.CD004002.pub2.
7. Herxheimer A, Petrie KJ. Melatonin for the prevention and treatment of jet lag. Cochrane Database of Systematic Reviews 2002, Issue 2. Art. No.: CD001520. DOI: 10.1002/14651858.CD001520.