My work in the outdoors began in college (circa 1996) where I would occasionally serve as an EMT for outdoor summer camps. It was a humbling start to a career in medicine, as I now work in cardiac surgery and critical care. Aside from my daily grind within the four walls of a hospital, I find myself still gravitating towards the wilderness for a sense of professional fulfillment. My greatest satisfaction has been to reach people in their critical times of need within the ranks of Portland Mountain Rescue (PMR). Since joining as a new recruit in 2012, I have worn the hat of president, vice-president, rescue-leader, medical committee chair, and now assistant medical director. Through this journey, I have learned, cried, celebrated, grown, and been challenged in so many ways. Despite all the time we spend in the remote alpine community we serve, most of us also have day jobs. We are an “all volunteer” team— each member bringing a unique skill set to, “save lives through rescue and mountain safety education.” Alongside some amazing men and women, I have been able to marry my front country practice of cardiac surgery and critical care with my backcountry practice of wilderness medicine.

One of the intrinsic challenges of the alpine environment is its remote nature and the limited resources available. Not to say this is a different trait than rescue work in other locales, but there are individual characteristics of every terrain location that demand intentionality in what you bring on-scene for the practice of wilderness medicine. If I can only fit so much in my pack, the questions arise:

• How much does this gadget weigh?

• Will I ever REALLY use this cool toy?

• Will it withstand the cold? The heat?

• How can I recharge the batteries?

Not long ago, I had the privilege of co-authoring an article, Alpine Cardiology, with my friend and climbing buddy, Gabe Webster. In this feature, we highlighted a novel product (KardiaMobile, a product of Alivecor) for obtaining remote ECGs through a device that weighs about as much my toothbrush. This device is so thin, it could almost double up as a bookmark in my personal copy of Vertical Aid, or whatever guide book I brought for the day. I still think it’s a pretty unique device and would consider throwing it in my pack on any adventure. As I write these words, a question arises: “Is there anything I wouldn’t throw in my pack?” My time with PMR as well as my Diploma in Mountain Medicine (DiMM) training with the team at the University of New Mexico, has pushed me to really consider the utility of everything I cram onto my back as I trudge uphill. One thing that I have almost never used is the ubiquitous tool of identity in front country medicine - the stethoscope. I remember the first Littmann I purchased in PA school and how proud I was the first time that I could hang it around my neck. Despite my affections for the bell and diaphragm, it never went in my rescue pack. I simply couldn’t justify the weight for its limited utility.

Over the years as my career matured, so did my auditory acuity. While I was better able to predict stenosis over regurgitation and the likely valve involved, I also found that my perception was also lessening. I had purchased a Butterfly Ultrasound to help my bedside evaluations, but something was still missing. My wife, who is amazingly patient, would repeat words to me if I couldn’t understand. The crackling voices of the rescue radio, however, were a little more challenging. Eventually, the muffled sounds of a masked voice in the OR led me to find an audiologist. I couldn’t believe what I had been missing. Hearing aids had opened up a world of acoustics I had been craving. With the help of my little Oticon buds, I could hear a cockroach fart on the other side of the hospital. The rescue radio had come alive for me. Indeed, I often found myself having to “turn down” the volume.

The stethoscope, however, was still a challenge. I couldn’t wear the hearing aids and the stethoscope at the same time. One manufacturer had implemented a stethoscope “adapter” that was a somewhat dysfunctional experience. Perhaps there was some user error, but I never figured out how to overcome the pain to hear heart and lung sounds. Cue the music of acoustic bliss - entering the ICU in a lab coat pocket was the new Eko DUO— an amplifying stethoscope that can also perform ECGs.

Was this a fancy piece of neck jewelry? Would it be a combined solution of telemetry and acoustic needs wrapped up in a sexy, sleek package? I had to know.

Looking at the device might lead one to furrow their brow. The Eko DUO is, dare I say, beautiful and robust simultaneously. It has all the appearances of a stethoscope until you take a gander at the transducer. It uses a button to adjust various filters to convert sounds from bell to diaphragm modes— all of which are amplified for the user’s fidelity needs. Volume is also adjustable. What’s more, is that the company (Eko Devices Inc.), has developed a versatile app allowing you to use all functions of the device. Information is transferred from the Eko DUO to your smartphone through LE Bluetooth technology (more on this later). Toggle through the bell/diaphragm modes and the user can not only hear the amplified sound of various pathology, but also record and share (HIPAA compliant) with colleagues for collaboration. This is also useful for educational opportunities with students. In geek language, the specs are as follows:

4 selectable audio filters:

Diaphragm 100-500Hz

Bell mode 20-200Hz

Midrange 50-500Hz

Extended 20-2000Hz

In addition to the assorted modalities, listening options are variable as well. One can use the Ekp DUO without the earpiece attached simply by wirelessly using the speakers of a smartphone, or connecting wired headphones to a smartphone.

Now, this is where things got a little peculiar as I became more oriented with the device. I was truly hoping for a device allowing me to leave my hearing aids in place. Alas, attempting to send the heart sounds back to my Bluetooth-compatible hearing aids was not a functional way of listening and produced a very low-fidelity sound. Furthermore, it contributed to an interference loop that persisted long after my iPhone was back in my pocket. In fact, I literally had to “force close” the app in order to shut off the static interference that was now constantly being sent to my hearing aids. In defense of Eko Devices’ product support, they don’t promote Bluetooth headphones as an option. I guess I was just hoping for a little more from the user interface. Using the phone speaker or wired headphones to play the anatomical sounds does produce excellent acoustics. From the standpoint of my hearing impairment, they are certainly more audible than my previous Littmann unamplified stethoscopes.

Looking at the other functions of the device, the same app that facilitates auscultating heart sounds also allows the user to make use of Einthoven’s triangle to obtain various ECG patterns. These are also able to be recorded and stored on the device. If I were to make side-by-side comparisons of the quality of the ECG in the Eko Devices Eko DUO vs. the KardiaMobile AliveCor ECG (previously reviewed here), I would certainly prefer the DUO device. The user interface and quality of the ECG is superb.

As I shift the conversation to wilderness applications, it is reasonable to investigate the durability of the Eko DUO stethoscope. The company doesn’t quote specs for drop testing or dustproof/ waterproof resilience. They describe materials as ,“6061 machined aluminum and high-impact ABS thermoplastic.” Speaking personally from experience, that translates into able to survive ground level falls on the hard surfaces of my hospital floor. I haven’t found any reported specs on temperature tolerances but can report that in the production of this article, my Eko DUO sat in the bottom of my pack, lying in the snow for multiple hours, prior to making a field debut. Another element of durability that is always important to me is battery longevity. Eko Devices thankfully designed an auto-shut off feature into the device for when I am too distracted to press a button- thus prolonging battery life. All in all, I can get through a week of rounds and afternoon clinic duties with a single charge.

So where does that leave me? Would the Eko DUO make it into my rescue pack? The Eko DUO weighs a paltry 7.3 ounces, just over an ounce more than my older unamplified Littmann stethoscope. Is either worth the weight? Should I finally start carrying a stethoscope into the vertical environment? Regardless of how I am about to answer the question, I want to preface my response as uniquely individual to my locale and practice environment. The reader will have to ask themselves the questions of weight considerations, recharging opportunities, environmental severity, etc.

I love the device for my hospital work but historically I have kept my rescue pack light, fast, and extremely focused on the demographics I might be serving. No kitchen sinks for this wilderness PA! There certainly are still some “kinks” to work out before I would call it the “perfect device” and yet, it is a fairly remarkable tool. I love the idea of having ECG/ telemetry in remote settings. As they say, a picture is worth a thousand words. I also feel the amplification of the anatomical sounds, especially considering the background noise of the wilderness rescue environment (wind, water, radios, helicopters, etc), might convince me of the potential future value of backcountry auscultation. Perhaps it is time for me to head out into the wilderness in search of a new rhythm or beat. LUB DUB… LUB DUB…