News & Features — 14 August 2023 at 10:25 am

Evidence Explorer: Updates and news from the academic community, Summer 2023

Dr Laura Clapham / Emergency Medicine Registrar / North Wales

Dr Lydia Potter / Junior Clinical Fellow / North Wales

Dr Holly Andrews / Anaesthetics Registrar / Evidence Explorer Lead / West of Scotland

The Red Rock Canyons, Colorado by Dr Lydia Potter

Whilst we’ve all sucessfully navigated another ‘first Wednesday of August’ and learnt that this summer is one for always co-packing GoreTex and factor 50 whilst out on adventure, the global health and expedition medicine academic publications have been flowing out.
It’s been a busy time for our team at Adventure Medic with many of us jetting off to global expeditions, supporting wilderness training and heading up global health endeavours and so we’ve drafted in two brilliant adventurous Doctors from North Wales. Drs Clapham and Potter have been scouring the academic community for interesting publications from their offices overlooking the impressive mountains of Snowdonia. Here they present a wide range of publications, from essential guideline updates from the UIAA on managing diabetes in the wilderness, to thought provoking prose on decolonising healthcare and our role in healthcare in the battle against plastic pollution.
We really have got something for everyone this issue – happy reading!

Dr Laura Clapham

Laura is in her third year of Emergency Medicine training in North Wales. She has a keen interest in Global Health and medicine in low-resource settings. During her time out of training, she has worked in rural Zambia, on board Mercy Ships in Guinea and Senegal, in Lesvos with Boat Refugee Foundation, been on expeditions to Madagascar and Honduras, worked at a ski field in New Zealand and in Darwin ED. In her spare time, she enjoys being immersed in cold water swimming or diving, and is trying to learn to some climbing skills to keep up with the North Wales crew!

Dr Lydia Potter

Lydia is a FY3 doctor living and working in Conwy, Snowdonia. She is currently doing a less than full time junior fellow job in Emergency Medicine and Paediatrics in Ysbyty Gwynedd, Bangor. In her spare time, she is part of the RNLI boat crew in Conwy and teaches on the Unique Expeditions UK courses. She has experience providing medical cover for ultra-endurance races, sports matches and festivals in the UK and abroad. She is working towards her Mountain Leader qualification in the hills of Snowdonia. When not at work, you can find her open-water swimming, hiking, climbing or bouldering in Eryri.
After her ‘F-free y
ear’ she is hoping to enter EM ACCS, continue doing expedition medicine work and eventually sub-specialise in PHEM.

Expedition and Wilderness Medicine

A group of hardy trail runners’ efforts being rewarded in Snowdonia

This quarter in wilderness and expedition medicine, we present six fascinating publications. These papers take us from Kilimanjaro, discussing the effect of menstruating on incidence of Acute Mountain Sickness (AMS) to California, looking at the dangers of endurance sports, analysing a case series that presents four runners requiring dialysis following an ultra-marathon. Detailed and practical guidelines have been produced by the UIAA (International Climbing and Mountaineering Federation) medical commission for managing diabetes in the mountain – fantastic news for any expedition medic taking a diabetic client into the wilderness. Equally, for those of us who feel rising stress when dealing with a pregnant client on expedition, Coffet et al have done our research for us, and produced a literature review detailing considerations for wilderness and remote travel for those in the first trimester. For the scientists in us, altitude physiology has been explored further, with Kammerer et al looking at the effects of hypobaric hypoxia on coagulation in healthy patients. Finally, we have been treated to more evidence-based guidelines, with an expert panel grouping together to supplement WMS clinical practice guidelines on the treatment, management and prevention of non-freezing cold injury and warm water immersion. There is plenty this quarter to inform and inspire and we hope these articles can improve your practice when you are out in the wilderness, wherever that may be.

A Preliminary Study of the Effect of Menstruation on the Incidence of Acute Mountain Sickness
Paul M, Wagner T, Tukel C et al. Emergency Medicine Journal. April 2023

Menstruating whilst on expedition…it’s a faff at best and can be a major issue at worst, but does it have any effect on physiological adjustment to altitude? For many years, women were excluded from high altitude activities and neglected from scientific studies based in such environments. Thankfully, this is now changing, with 50% of those engaging in high altitude expeditions being women(1). This study by Paul et al aimed to compare the incidence of acute mountain sickness (AMS) between women who were menstruating and those were not menstruating during an ascent of Kilimanjaro (5895m). A secondary outcome was the use of AMS prophylaxis on this relationship. AMS was defined by the Lake Louise Consensus Scale and the expedition doctor’s clinical judgement. 46 women were included in the study, all from the same expedition, with 17 women menstruating. No significant difference in AMS incidence was found between women who were and were not menstruating or any effect of prophylaxis use on this relationship. The main limitation of this study was its size and lack of rigorous controls. However, the results certainly provide the start of a more solid evidence base to use when advising female participants on expedition. Larger-scale studies are still needed to fully define the relationship between hormonal influences on AMS incidence, but the findings of this work do go some way to help address the discrimination and misinformation about female athletes operating in extreme conditions. The findings may also act to reassure those having that heart-sink feeling when they realise their cycle lines up with their high-altitude expedition!

UIAA Medical Commission Recommendations for Mountaineers, Hillwalkers, Trekkers and Rock and Ice Climbers with Diabetes
Hillebrandt D, Gurtoo A, Kupper T et al. High Altitude Medicine and Biology. June 2023

Diabetes is a huge topic with a large prevalence, so it is unsurprising the UIAA Medical Commission’s advice article is a sizeable read. Whilst diabetic emergencies in remote locations can be fatal, there is no reason a knowledgeable diabetic who is skilled in self-care cannot function well in an extreme environment. It is clear the UIAA community wishes to support diabetics to safely enjoy all aspects of mountaineering and this recommendation document is an informative read for those wishing to support mountain expeditions with diabetic participants.
The UIAA (International Climbing and Mountaineering Federation), abbreviated by its French name, Union Internationale des Associations d’Alpinisme, is the international governing body for climbing and mountaineering, advising on issues such as mountain safety, sustainability and competitive sport. This recommendation article is split into seven numbered sections. The first four sections (introduction to the guideline document, introduction to diabetes, managing diabetic emergencies and caring for diabetic competitive climbers in non-remote settings) are written in non-technical terms, for the reading of the lay person. Sections five and six are written for clinicians, with section five focusing on insulin-dependent diabetes mellitus and section six on mountaineers taking oral hypoglycaemic medication. These two sections are fantastic, laying out the evidence clearly and advising on practical aspects of diabetic care at altitude; from the effects of temperature on insulin storage to how Acetazolamide prophylaxis affects glucose regulation. Section seven discusses recent technology developments in d
iabetic care, including insulin pumps and continued glucose monitors; setting out the pros and cons of modern diabetic technology use in a remote area. Given the prevalence and popularity of such devices, this final section is highly topical and enlightening. Whilst lengthy, this recommendation document contains all the information one could need when supporting diabetic patients in the mountains and is a vital read for any medic accompanying such a patient on expedition.

Effects of Hypobaric Hypoxia on Coagulation in Health Subjects Exposed to 3,500m Altitude
Kammerer T, Walzl A, Müller T et al. High Altitude Medicine and Biology. June 2023

Trauma at altitude is thankfully rare, but in an environment of rock faces, crevasses and seracs, when trauma does occur it can be significant. Whilst major trauma ultimately requires extrication and evacuation to in-hospital care, knowledge of the effects of altitude on coagulation and trauma-induced coagulopathy can be useful for the expedition medic practicing at altitude. Hypoxia is thought to be a trigger for pro-thrombotic changes, both in critically unwell patients and in healthy people at altitude, but do patients really bleed more at altitude? This small-scale study used twelve healthy females controlled for their variables and studied their functional coagulation and blood lysis at both a hypobaric hypoxia equivalent to 3,500m and at normoxia. Plasma-based coagulation tests were also done. There were no significant changes found, with no difference between lysis ability, clotting time, clot formation, clot amplitude or clot firmness. Kammerer et al concluded that moderate hypobaric hypoxia has no influence on blood coagulation in healthy females. This is a small-scale, but highly controlled study with interesting results that dispel some commonly accepted beliefs. Whilst this study should not change extrication plans for the trauma patient at altitude, it may have implications for risk stratification and certainly for future research.

Prevention and Treatment of Non freezing Cold Injuries and Warm Water Immersion Tissue Injuries: Supplement to Wilderness Medicine Society Clinical Practice Guidelines for the Prevention and Treatment of Frostbite
Zafren K, Hollis S, Weiss E et al. Wilderness and Environmental Medicine Journal. June 2023

In our Spring Evidence Explorer, we discussed Tipton & Eglin’s article ‘Non-Freezing Cold Injury [NFCI]: A Little-Known Big Problem’, which highlighted the difficulties in assessing, preventing and treating this condition due to its unclear mechanisms. Immersion injuries including NFCI and warm water immersion injuries often affect the feet, mostly of those operating in cold and/or wet regions for prolonged periods of time. These injuries are debilitating, painful and can be expedition-ending when affecting those required to walk long distances. To supplement the current Wilderness Medical Society guidelines, a panel of experts have gathered to develop evidence-based clinical guidelines for the evaluation, differential diagnoses, treatment and prevention of NFCIs and warm water immersion injuries. This article presents the available evidence alongside clear recommendations from the expert panel. It is well worth a read for anyone likely to encounter patients with immersion injuries – anyone working in environments where feet are soggy for prolonged periods of time.

First-Trimester Pregnancy: Considerations for Wilderness and Remote Travel
Coffet CH, Casper LM, Reno EM et al. Wilderness and Environmental Medicine Journal. June 2023

Whilst heavily pregnant women are unlikely to be involved in expeditions in extreme environments, those in their first-trimester may partake in many outdoor activities with ease. Additionally, a person may discover their pregnancy during an expedition or even travel unknowingly during this period. This literature review addresses diagnostic and management considerations in multi-day expeditions during the first trimester of pregnancy. The article covers both gynaecological considerations, including vaginal bleeding, suspected ectopic pregnancy and threatened pregnancy as well as non-gynaecological considerations, including treating infections, dealing with nausea and vomiting and vaccinations recommendations. Clinicians working in extreme environments should be prepared to answer queries about travelling during first-trimester pregnancy and be comfortable prescribing, treating and determining the need for evacuation. Even if an expedition medic believes there are no pregnant participants on their trip, it may be a possibility and one should be prepared for any eventuality. This article addresses commonly encountered questions and presents available research, helping us all to advise with a solid evidence base.

Four Cases of Acute Kidney Injury Requiring Dialysis in Ultramarathoners
Pasternak AV, Newkirk-Thompson C, Howard  JH. Wilderness and Environmental Medicine Journal. June 2023

The popularity of ultra-endurance events are on the rise and it’s easy to see why. Participants can race through stunning landscapes with a ‘run when you can, walk when you want’ attitude, focusing on the journey, not the completion time. With a huge range of ultra-endurance race providers operating in almost every environment possible, there is a magnitude of events to choose from. Clinicians working in event medicine, particularly in ultra-marathons, will be used to advising athletes to keep hydrated and avoid non-steroidal anti-inflammatories (NSAIDs) such as ibuprofen. This advice comes from a desire to avoid a pre-renal acute kidney injury (AKI) and exertional rhabdomyolysis, but are we and our clients truly aware of how serious this can become? This interesting case series by Pasternak et al presents four cases of AKI requiring haemodialysis following ultra-endurance footraces. The four runners discussed had all run the Western States 100-mile Endurance Race (WS100) in sunny California over a three year span. Importantly, the race day temperatures were high, ranging from 36.6-38.3 degrees Celsius. All four runners presented to secondary care 17-32 hours following their race with biochemical findings of rhabdomyolysis, hyponatraemia and AKI. All four had symptoms of nausea, vomiting, dark urine and muscle cramping during their race and their presenting symptoms on arrival at hospital were ongoing fatigue, myalgia, nausea and vomiting, with one runner experiencing haematemesis. One participant had taken 200mg Ibuprofen, but all others had avoided any medications. Typically, AKI and exertional rhabdomyolysis is transient and does not require dialysis; however, all four of these runners required haemodialysis for between 10 days to 6 weeks. Despite the seriousness of their presentations, all four patients did recover fully and returned to endurance running with no chronic kidney disease. This case series is a really interesting read and provides some great evidence to take renal issues in endurance sport seriously. For budding wilderness medics, endurance races may be the first exposure to expedition medicine and this study highlights how vital it is to advise athletes on hydration, electrolyte intake and the avoidance of NSAIDs.

Global Health and Humanitarian Medicine

Laura Clapham sharing her breakfast with the hippos in South Luangwa national park, Zambia

This quarter’s global health publications present many thought provoking topics that provide an evidence base for instigating essential discussions within our communities and give inspiration for meaningful action and change.
The first two articles discuss the inter-relationships between artificial intelligence and plastic pollution to our healthcare systems and not only explain the problem but also provide helpful ways in which we might take steps to improving both. Decolonisation throughout the world has been a hot topic over the past year and its importance within health systems is incredibly important in the drive to promote heath equity. Laura presents two excellent articles below related to this giving advice on how we as individuals can take steps to helping improve global health equality.
Over the past decades we’ve seen an ever increasing flow of UK doctors drawn to Australia to work. Such an opportunity is exciting but it is important to pause amidst drowning in visa admin to consider our potential impact on the native communities there prior to arrival. Crocetti et al describe the problems with alcoholism within Aboriginal communities and highlights the potentially disastrous impact that global companies can have on this.
And finally, in a previous evidence explorer edition we talked about the bi-directional benefit of working in LMICs highlighting the article by Walpole et al and here we present another providing evidence of the skills gained during global health placements.

Threats by artificial intelligence to human health and human existence
Federspiel F, Mitchell R, Asokan A et al. BMJ Global Health. May 2023

Artificial intelligence (AI) has enormous potential to benefit healthcare. Yet most of us are immediately drawn to horror films where AI destroys the planet and the human race forever. This paper takes a more logical approach and examines the potential threat to human health and wellbeing through social, political, economic and security-related factors. If “narrow AI” (a learning algorithm designed to perform a single task) is misused, it could threaten human health by controlling and manipulating people, enhancing lethal weapon capacity and rendering human labour obsolete. And maybe those movies weren’t fantastical after all; the development of self-improving artificial general intelligence (AGI) could pose an existential threat to humanity. The authors call for effective regulation and the prohibition of certain AI types and applications, and even suggest a moratorium on self-improving AGI development. It is a rapidly evolving technology and perhaps the medical community should be advocating for social and economic policies which advocate for safe AI to protect future generations?

Supplement: Plastic pollution: how can the global health community fight the growing problem?
Bidashimwa D, Hoke T, Ba Huynh T et al. BMJ Global Health. June 2023

From AI to plastics, the threat to human health is real. The UN defines the principle of “One Health” as “an integrated, unifying approach… to sustainably balance and optimise the health of people, animals and ecosystems.” (2) This paper details how plastic pollution negatively impacts all three. It goes on to argue that the global health community has not been very vocal on the issue. Despite the global crisis and the burden it poses, the authors’ literature search found only 65 articles on plastic pollution in 15 out of the top 50 global health journals in the past 5 years. They include a call to action and suggest: 1) filling the evidence gap, 2) employing a multi-disciplinary approach with environmentalists and animal health specialists, 3) using a circular economy for medical plastic waste, and 4) engaging with global, national and local health leaders to advocate for effective interventions. Perhaps next time we throw away the waste from a cannula, we can pause and ponder what part we can play in the big picture?

Global health has deep roots in colonialism and these structures still persist today. These two papers provide insight into the problem and consider the future of deconstruction.

Colonization and decolonization of global health: which way forward?
Hussain M, Sadigh M, Sadigh M et al. Global Health Action. Nov 2022

This article is a sobering reminder how ingrained colonialist ideas have birthed and molded global health as we know it today. It highlights historical examples of the negative health impacts these structures have had and challenges whether we can begin to change them while operating within them. It demonstrates how medical progress has benefited people of the colonial powers and exploited vulnerable groups. Still today, global health partnerships “that aim to help often mirror colonial relationships with members of high-income countries being given greater opportunities (mentorship, employment opportunities, leadership positions, compensation) in low income countries than the other way around”. The “Next Steps” section will leave you with much food for thought as the authors present some tough questions on the future of decolonising global health.

Drivers of health workers’ migration, intention to migrate and non-migration from low/middle-income countries, 1970–2022: a systematic review
Toyin-Thomas P, Ikhurionan P, Omoyibo EE et al. BMJ Global Health. May 2023

Following on from decolonising global health, this study aimed to understand the factors driving healthcare workers’ migration from low/middle-income countries (LMICs). They analysed 107 studies published between 1970 and 2022, focusing on doctors and nurses from 26 countries. The key drivers were found to be remuneration, security problems, career prospects, working environment and job satisfaction. These factors remained consistent over the last five decades and were similar across geographical regions in LMICs. With evidence now to guide action we hope that better progress can be made to support LMICs in retaining their health worker populations. 

Surgery: a crucial ally for universal palliative care access
Rosa WE, Lumati JS, Alatise OI et al. The Lancet Global Health. May 2023

Surgery is all about cutting, right? But what happens when cutting can no longer cut it? Pun absolutely intended. This paper reminds us of the inequalities in access to palliative care globally, and argues that collaboration between surgical and palliative care teams could help bridge health gaps. Globally, 5 billion people lack surgical care while 61 million suffer for want of palliative care. 64% of countries lack palliative care access, mainly low-income ones. A multidisciplinary approach involving surgeons is crucial, particularly in low-income countries, to address unmet needs. If you are thinking of working or have worked in surgery in a low-income country, integrated palliative care is perhaps something to consider when planning your resource allocation. 

‘A recipe for cultural disaster!’– a case study of Woolworths Group’s proposal to build an alcohol megastore in Darwin, Northern Territory
Crocetti A, Cubillo B, Walker T et al. Globalization and Health. June 2023

If you have spent time in the Northern Territory (NT) of Australia, you will know what a beautiful and culturally important place it is. Aboriginal culture is one of the oldest on the planet and yet they have been treated appalling in recent history. [I recommend reading Dark Emu for more on this]. In order to alleviate some of the problems caused by alcohol, so-called ‘dry’ communities have banned alcohol. This study delves into the impact of commercial activity on Indigenous populations, focusing on the effects of the alcohol industry in Australia. The supermarket chain Woolworths aimed to build a large alcohol store near ‘dry’ Aboriginal communities in the NT. Through interviews and data analysis, the study reveals Woolworths’ tactics, including lobbying and divisive rhetoric, disregarding existing evidence of harm. Advocacy efforts, emphasising unity and Aboriginal leadership, countered these tactics. It is inspiring to read how these strategies can protect Indigenous health against powerful commercial interests.

Applicability of working abroad for physicians with a specialization in Global Health and Tropical Medicine
Ozcan H, Overeem L, Bakker M et al. Globalisation and Health. April 2023

“So please tell us how your experience overseas has helped you in your work in the NHS…” This may be a familiar question in interviews or even in casual conversation at work. Sometimes it is hard to put it into words. Well, this study may provide a useful talking point. In the Netherlands, the Global Health and Tropical Medicine training programme involves 27 months of training in Obs & Gynae, Surgery and/or Paediatrics followed by a six month internship in a low-middle income country (LMIC). The study explores the competencies developed by physicians specialising in Global Health and Tropical Medicine during their work in low-resource settings (LRS) and their applicability in high-resource settings (HRS). Using qualitative methods, the study identifies 15 themes including cultural awareness, communication skills, public health, teamwork, and many others. These competencies enhance physicians’ professional, personal and cultural perspectives, potentially improving healthcare delivery in both LRS and HRS. A really useful read whilst reflecting on your own experiences working in low resource settings. 

Thank to our collaborators this quarter, we’ve really enjoyed having you on board.
As always, do get in contact if you’d like to be involved with contributing to future releases of this feature – we always look forward to hearing from you.


  1. Twombly  SE, Schussman  LC. Gender differences in injury and illness rates on wilderness backpacking TRIPS. Wilderness Environ Med 1995;6:363–76.