Letters to the Editor
Re: Self-Rescue During High Altitude Ascent
Tom Murphy MA (Cantab) MPhil MBBS FRCA, Consultant Anaesthetist, Aintree Hospital, Liverpool, UK
Paul Spackman, Expedition Leader, SummitClimb
Adrian North, PhD Candidate, University of California, Berkeley
February 4th, 2025
High Altitude Pulmonary Edema (HAPE) is a common but potentially catastrophic consequence of ascent to high altitude. Current guidelines* suggest nifedipine as first-line treatment, alongside descent and/or oxygen therapy. Sildenafil may also be used, but is considered to be less effective and as such is a second-line treatment.
On a recent expedition up Ama Dablam, Nepal (6812m), a 32 year old client who had no pre-existing health problems and had previously been entirely symptom-free of the effects of altitude, became suddenly unwell near Camp 3 (6300m), with extreme shortness of breath on minimal exertion. This took place at around 3AM Nepali Standard Time, with no realistic prospect of immediate rescue. Recalling a similar incident the previous year in which a client showed symptoms of postural hypotension following nifedipine administration, necessitating alternative means of rescue, the expedition leader gave him 50mg sildenafil on the basis that this could allow the client to descend safely to a lower altitude. The client subsequently descended to base camp and his symptoms cleared up completely within 48 hours.
Nifedipine, a calcium-channel blocker, is routinely used in the management of hypertension. In naive, normotensive patients, it can cause rebound hypotension. It is however, very effective in the management of pulmonary hypertension and thus is useful in the treatment of HAPE, believed to be mediated by hypoxic pulmonary vasoconstriction. In contrast, sildenafil, a phosphodiesterase-5 inhibitor, is less effective in the treatment of HAPE but does have a well-established use in pulmonary hypertension. While sildenafil can also cause hypotension, its enormous success in the treatment of erectile dysfunction emphasizes that it can safely be used in anticipation of moderate-level physical activity. Other factors such as hydration status should be optimized where possible, given that during a high-altitude summit push, dehydration is common.
We suggest that while further work is required to compare the efficacy of nifedipine and sildenafil in HAPE, in the dynamic and multi-factorial world of expedition medicine, logistical and environmental concerns may sometimes mean that sildenafil is a wiser choice than nifedipine. Given that these decisions are often made by non-medically trained professionals, we suggest that sildenafil should be considered as first-choice management when logistics favor self-extraction over alternative means such as helicopter rescue, with the option of adding nifedipine in refractory cases.
* WMS Summary Recommendation for treatment of HAPE: “We suggest that tadalafil or sildenafil be used for HAPE treatment if descent is impossible or delayed, access to supplemental oxygen or portable hyperbaric therapy is impossible, and nifedipine is unavailable. Weak recommendation, low-quality evidence.”
Re: Battlefield Ukraine
Jamison Geracci, BS
Kyle Carr, M.Sc
September 14, 2024
Original article: Battlefield Ukraine
The purpose of this letter is neither to argue the statements of Gordon Giesbrecht, but to amend with updated information. The tactics and experiences on the Ukrainian battlefield have led to specific medical adaptations. Of note, three items of growing importance are the use of drones on the battlefield, the effects of unmitigated hypothermia, and the consequences of having a diminished number of educated and capable first responders available at point of injury.
1. Use of consumer-quality drones with relatively high effectiveness in locating and tracking opponents on the battlefield has a clear carryover to wilderness medicine and Search and Rescue tactics. The speed and relative ease with which simple store-bought drones can locate enemy Soldiers on a battlefield shows that they may be at least as effective in a non-combat environment with less signal noise.
2. Hypothermia and cold injury have proven to be a large threat even to healthy troops, thus it has been found that the decision to make a combat casualty “trauma naked” must be weighed against environmental and/or tactical factors. This is not a foreign idea to wilderness medicine.
3. To expand upon challenge number 5 as listed in the original article, the Ukrainian Army is faced with the challenge of trying to continuously update and improve the quality of care at and near the frontline with an ever-dwindling supply of previously trained medical professionals. An American serving with Ukrainian forces claimed the life expectancy of a new soldier on the frontlines had a life expectancy of just four hours. As a consequence of this brutal and prolonged warfare, the forces in Ukraine must rely on larger numbers of inexperienced medics. This is also pertinent to one of the great wilderness medicine conundrums of (often) relying on layperson first aid over a prolonged time before reaching, or being reached by, higher levels of care.
References
Curry, C. (2023, February 13). Nonstop shelling: Former US Marine fighting in Bakhmut describes intensity of fighting. ABC News. https://abcnews.go.com/International/nonstop-shelling-former-us-marine-fighting-bakhmut-fighting/story?id=97324824
Quinn, J., Panasenko, S. I., Leshchenko, Y., Gumeniuk, K., Onderková, A., Stewart, D., Gimpelson, A. J., Buriachyk, M., Martinez, M., Parnell, T. A., Brain, L., Sciulli, L., & Holcomb, J. B. (2024). Prehospital lessons from the war in Ukraine: Damage control resuscitation and surgery experiences from point of injury to role 2. Military Medicine, 189(1–2), 17–29. https://doi.org/10.1093/milmed/usad253
Re: Rescue Dogma in the Age of Evidence-Based Medicine
Alison Sheets, MD
September 19th, 2020
To the Editor-
I read the article about "dogma" by Corey Winstead. While I am happy that he is getting updated information about spinal injury and suspension syndrome out to WMS members, replacing one dogma for another is not in anyone's best interest. There are many variables that determine when amid-wall litter load might or should occur. Simply picking off a patient with pelvic or femur fractures, for example, could definitely cause harm. With a combative patient, when multiple pitches need to be negotiated or when complex terrain is present, among other factors, a litter may be the best choice.
In the Rocky Mountain Region of the Mountain Rescue Association (MRA) we test teams in mid-wall litter loads for team accreditations, and re-accreditations. While my team performs this technique on actual rescues at least once a year, many SAR teams never do mid-wall litter loads. Our region teams and leadership have had this discussion about pickoffs instead of mid-wall litter load many times over the years. Bottom line is that a high angle rescue team should be practiced in this technique and when it is the best thing for the patient, they should be able to perform it smoothly and efficiently. While I agree that pickoffs are often more efficient, it is not the only way, or necessarily the best way, to evacuate a patient from vertical terrain.
Respectfully,
Alison Sheets MD
WMS SAR committee chair
MRA Vice President
ICAR MEDCOM Vice President
Medical Director Rocky Mountain Rescue Group
University of Colorado Wilderness and Environmental Medicine Fellowship Technical Adviser