Friday, March 20, 2015

Medical Helicopters Revisited

(To all: This one is fairly esoteric...some thoughts I put together while revising a chapter on Air Medical Transport for a textbook of Emergency Medicine. I wrote it like I was going to send it somewhere for publication, like actual smart people tend to do. Turns out I was going to send it to me, which undoubtedly says something...)

Twenty years ago, I wrote the first chapter on air medical transport in a major textbook of Emergency Medicine. Every few years there’s a revision, and that’s why in the second edition I asked my colleague Ira Blumen to join in the effort. I did so because Dr. Blumen is a prolific writer and a respected authority, and because his participation meant that it was my turn to revise the chapter every six years instead of every three. But the years have gone by, and now it’s my turn again.

The chapter is pretty much what you would expect. It talks briefly about the history of air medical transport, rotor wing and fixed wing vehicles, crew configurations, and the like. For me, the fun of the working with the chapter has always been the sections on indications for transport and the efficacy of air medical care. So it was with a mixture of delight and dismay that I found that it was virtually unchanged from last millennia’s work.

When I was a young academic and prone to pronouncement, pontification, and polysyllabic pontification (not to mention alliteration), I used to give lectures about rotor wing air medical transport to other health care professionals. At the time, air medical transport was…and I suspect it still is…a private club, where only those who hold membership know the secrets. So while I would talk to EMS groups and referring physicians about all the wonderful things helicopters could do for them and that just like voting in Chicago they should call us early and often, to those inside the walls I would show this slide that said everything we definitively knew about air medical transport:

Helicopters are fast.
Helicopters are expensive.
Helicopters crash.

That was it. The bottom line was that anything that seemed to be an indication for transport was related to speed, either to get the patient to definitive care or to bring needed resources, such as ALS, to the patient’s side. And I think we can accept the latter two propositions without lot of fuss.

Now it’s twenty years later. Professionally, I’ve gone from academics to private practice to public health to being a State Health Officer, and now I’m back in the ER again. I’m on child #1, wife #2, and dog #3. I wrote articles, then wrote columns, then reviewed legislation, and now I blog the ramblings of an aging mind ( But the more things change, the more they stay the same…or even more so. That’s why today’s slide would read:

Helicopters are fast.
Helicopters are expensive.
Helicopters crash.
Helicopters are even less useful today.

It gives me pains to add that last line. My first job out of residency was as the Medial Director for the ShandsCair Flight Program in Florida. (Over the years, I’ve also worked with a private, fee-for-service program in South Africa, and with a law-enforcement HEMS unit in Daytona Beach.) I loved everything about it. The flight team…pilots, nurses, paramedics, dispatchers…were the closest group of folks I’ve ever worked with, and in the tight circles of ER life that’s saying something. I miss them every day, just as I miss the adventure of jumping a flight or the thrill that comes acting the airborne angel, swooping in from above to save lives with powers and abilities far beyond those of mortal men. I miss the fact that we often left the door to the helicopter unlocked, and that I could take University of Florida coeds out there at night to see MY helicopter and make out in the back, praying that the team wouldn’t get scrambled and we’d need to run off into the bushes nearby.

But there’s no escaping the reality that the utility of air medical transport, and especially that of helicopters, is less than it was. This isn’t the fault of the industry. I truly believe that the ANT community has been doing everything it can to provide service and to find new niches were they can be of use. The issue has to do with the fact that the medical landscape has changed radically within the past two decades.

Let’s take a couple of high-profile examples. It’s always been maintained that helicopters save lives of trauma victims. This was undoubtedly true, and especially so in rural areas where field care was often BLS at best, and the diagnostic capabilities of rural hospitals was essentially non-existent. But even early on it seemed that the advantage was not so much with the helicopter itself, but with the fact that it often brought ALS care to the patient, and most specifically airway management skills. It also seemed clear that whatever advantage was accrued by HEMS was a result of the aircraft being integrated into a complete trauma system, with a Trauma Center at its core, rather than as a single, isolated asset. And there appeared to be no real logistical or clinical advantage to using rotor wing EMS in the vast majority of urban responses, essentially limiting the efficacy of air transport for trauma to the rural setting.

Fast forward to today. Many rural EMS services have now upgraded to ALS, and many of these ALS services can use advanced techniques such as rapid sequence intubation. Even BLS services now use advanced airway modalities such as the laryngeal mask airway and the Combitube, giving them the ability to hold airways open in the field. These skills in and of themselves mitigate one of the major benefits of air medical transport. In addition, the majority of small rural hospitals…even those Critical Access Hospitals (CAH)…now have CT scanners with teleradiology review of both plain films and scans. While there are clearly some unstable patients who need to get to a trauma center as fast as possible, I would argue that there is an increasing subset of patients who can be initially stabilized and evaluated at a small local facility. And while there are some injures that, after evaluation, would mandate immediate transfer to a Trauma Center, there are other injures (extremity fractures and soft tissue injuries come to mind) where I would argue that it’s nearly impossible to discern any clinical difference between patients transported by ground or air.

I believe the same phenomena to be true with acute medical emergencies such as acute myocardial infarction and stroke. There is a body of literature indicating that some acute MI patients in outlying areas can benefit more from being given a thrombolytic in the rural setting before being transported to an interventional center than they can from simply a longer before catheterization and angioplasty. (This advantage rises with greater distances to definitive care.) And once you get an initial thrombolytics, how much more myocardium is saved by air transport versus ground? Does the extra time equal any amount of tissue? Do we know?

A similar scenario is seen in those with acute stroke, where the advent of remote CT scanning allows physicians at rural hospitals to check for bleeds before administering thrombolytics. Once administered, the patient needs to be monitored for bleeding, but if the patient is stable does transport to a stroke center by air offer any further advantage than transfer by ground? Do we lose any more brain cells? Do we know?

(It’s also important to note that when we talk about time saved, we need to compare air transport to ground transport total mission times. Given that ground EMS is often nearby versus air transport, which needs to be “called in” from afar while the patient merely waits, time differences become even more negligible.)

One might point to the proliferation of published works in air medical transport as a way to counter these thoughts. But if you were to look closely at the literature (which I’ll be doing every six years or so when it’s my turn for the revision), the vast majority of clinical works are case series that can be summarized as “Look who we can safely transport by air.” (Granted, “safely” is a relative term given the accident rates for air medical transport as opposed to general and commercial aviation statistics.) Much of the remainder of the literature is devoted to studies of air medical programs, crews, and equipment…demographics, human factors studies, and the like. These are valuable, but they still don’t get us to the key question of efficacy. Efficacy can only be evaluated in comparison studies, and given the proliferation of AMT programs within this country, the opportunity to do head-to-head studies out outcomes in patients transported by air or ground may have been permanently lost. In brief, the literature is very good at illustrating what we CAN do. It does a poor job of indicating what we SHOULD do.

Let’s be honest, as members of the club. In the majority of cases, air medical transport is used mostly as a taxi service to either make a doctor’s life easier by getting a patient out of a facility or not having to see the patient at all, or to help EMS avoid a long drive. (I am willing to accept that in some cases, it’s probably in the patient’s best interests to get away from the doctor or EMS crew as well. As the old joke goes, they still call the guy who graduated last in his med school class “Doctor.”) But neither of these factors has anything to do with if the patient actually needs transport by air or would do equally well by ground. And so we enter a vicious cycle. If AMT programs were to do the academically correct thing and screen calls based only clinical efficacy, volumes drop, as do revenues, as does the viability of the flight service itself. And if objective efficacy becomes the standard for payment…which, as a former policymaker, I would certainly make a condition of reimbursement in an overhaul of government-based fiscal payment schemes…well, you get the picture.

There is no question in my mind that there will always be a role for rotor-wing and fixed wing transport in rural areas, with need rising in proportion to distance to definitive care. There will also always be a need for rapid deployment of specialty teams, such as those caring for neonates. And it should be noted that my comments are rather specific to the United States…in nations where CT scanners are not ubiquitous, roads are spotty, and ground-based EMS is few and far between, my thoughts may, and probably should, be radically different. But it seems that in many ways, air medical transport remains like hyperbaric oxygen…a “therapy in search of diseases.” The sooner we find those diseases, the better off we’ll be.

I want air medical transport to survive. I want it to thrive. But there are hard times ahead, and we may as well face it. Only by doing so can I insure that my son, should he chose to go into medicine, will have the opportunity to make out with a coed in the back of a helicopter. Gotta tell you…it’s pretty cool.

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