Altitude-Related Disorders on Mount Kilimanjaro, Tanzania: Two-Year Survey in a Local Referral Center.

INTRODUCTION: A significant number of climbers on Mount Kilimanjaro are affected by altitude-related disorders. The aim of this study was to determine the main causes of morbidity and mortality in a representative cohort of climbers based on local hospital records. METHODS: We conducted a 2-y retrospective chart review of all patients presenting to the main referral hospital in the region after a climb on Mount Kilimanjaro, including all relevant records and referrals for postmortem studies. RESULTS: We identified 62 climbers who presented to the hospital: 47 inpatients and 15 outpatients. Fifty-six presented with high altitude illness, which included acute mountain sickness (n=8; 14%), high altitude pulmonary edema (HAPE) (n=30; 54%), high altitude cerebral edema (HACE) (n=7; 12%), and combined HAPE/HACE (n=11; 20%). The mean altitude of symptom onset ranged from 4600±750 m for HAPE to 5000±430 m for HAPE/HACE. The vast majority of inpatients (n=41; 87%) were improved on discharge. Twenty-one deceased climbers, most having died while climbing (n=17; 81%), underwent postmortem evaluation. Causes of death were HAPE (n=16; 76%), HAPE/HACE (n=3; 14%), trauma (1), and cardiopulmonary (1). CONCLUSIONS: HAPE was the main cause of death during climbing as well as for hospital admissions. The vast majority of climbers who presented to hospital made a full recovery.

The Death Zone: Lessons from History.

This Lessons from History article about the naming of the extreme altitude "Death Zone" explores the historical mountaineering and medical literature relevant to the topic. Swiss alpinist and radiologist Edouard Wyss-Dunant (1897-1983) authored several reports and books about expeditions to arctic regions, deserts, and the Himalaya. Encouraged by the success of a Swiss expedition to the Garhwal Himalaya in 1947, Wyss-Dunant joined his fellow climbers from Geneva on a 1949 expedition to several peaks in the Kanchenjunga region. Wyss-Dunant was then invited to lead the spring 1952 Swiss Everest expedition. Despite this being the first Swiss attempt on Everest and on an untried route, Raymond Lambert and Tenzing Norgay nearly summitted Everest from the Nepal side. Wyss-Dunant earned mountaineering immortality by coining the phrase the Death Zone during the expedition's foray into the upper regions of Everest. Wyss-Dunant went on to become a president of the Swiss Alpine Club and the International Climbing and Mountaineering Federation. His writings and that of others provide an evocative supporting narrative to illustrate some of the problems of living (or dying) at extreme altitude.

Sudden Cardiac Arrest and Cardiopulmonary Resuscitation with Automated External Defibrillator in the Austrian Mountains: A Retrospective Study.

Background: Few data exist on the likelihood of surviving sudden cardiac arrest in the mountains. The aim of this study was to analyze the epidemiology and outcomes of patients suffering sudden cardiac arrest and undergoing cardiopulmonary resuscitation (CPR) with automated external defibrillator (AED) in the Austrian mountains. Materials and Methods: We analyzed all cardiac arrest cases in the Austrian mountains reported in the nationwide Austrian Alpine Police database from October 26, 2005, to December 31, 2015. To obtain information on outcomes, these patient data were manually merged with patient data from the main Austrian referral center for mountain emergencies, Innsbruck Medical University Hospital. Results: Overall, 781 cases of sudden cardiac arrest in the Austrian mountains were recorded. In 136 cases (17%), CPR with AED was attempted. The most frequent activities at the time of sudden cardiac arrest were hiking (n = 63, 46%) and skiing or snowboarding (n = 44, 32%). In the nationwide Austrian Alpine Police database, only 4 (3%) patients survived, whereas in the Innsbruck Medical University Hospital database, there were seven survivors who received CPR and AED. All survivors had received immediate CPR with an AED. Five patients had good neurological outcome (cerebral performance category 1-2). Conclusions: In the Austrian mountains, CPR was attempted in less than 20% of sudden cardiac arrest cases. The few that survived had received immediate CPR with an AED. To better understand the circumstances and outcome of sudden cardiac arrest in the mountains, out-of hospital and in-hospital data should be linked.

High altitude hypoxia as a factor that promotes tibial growth plate development in broiler chickens.

Tibial dyschondroplasia (TD) is one of the most common problems in the poultry industry and leads to lameness by affecting the proximal growth plate of the tibia. However, due to the unique environmental and geographical conditions of Tibet, no case of TD has been reported in Tibetan chickens (TBCs). The present study was designed to investigate the effect of high altitude hypoxia on blood parameters and tibial growth plate development in chickens using the complete blood count, morphology, and histological examination. The results of this study showed an undesirable impact on the overall performance, body weight, and mortality of Arbor Acres chickens (AACs) exposed to a high altitude hypoxic environment. However, AACs raised under hypoxic conditions showed an elevated number of red blood cells (RBCs) and an increase in hemoglobin and hematocrit values on day 14 compared to the hypobaric normoxia group. Notably, the morphology and histology analyses showed that the size of tibial growth plates in AACs was enlarged and that the blood vessel density was also higher after exposure to the hypoxic environment for 14 days, while no such change was observed in TBCs. Altogether, our results revealed that the hypoxic environment has a potentially new role in increasing the blood vessel density of proximal tibial growth plates to strengthen and enhance the size of the growth plates, which may provide new insights for the therapeutic manipulation of hypoxia in poultry TD.

Deaths at high altitude: Reducing the risk. A preliminary field study.

BACKGROUND AND AIMS: Altitude-related medical literature provides very few simple clinical studies relating to those on 'adventure holidays'. Systemic blood pressure has seldom been studied closely in relation to altitude. This study aimed to address both these issues and to assist GPs approached by patients for pre-trek advice. METHODS AND RESULTS: A total of 17 hillwalkers, evenly distributed for gender and age, trekked gradually from moderate to extreme altitude on Mera Peak in the Himalaya, noting any altitude sickness symptoms. Heart rate, blood pressure, oxygen saturation, peak expiratory flow and core temperature were measured daily. Altitude was double-checked hourly and synchronised with each set of measurements. On each day, two individuals wore 24-h ambulatory blood pressure monitors for assessment of altitude effects. Two principal findings emerged. Firstly, none of our 17 developed altitude-related symptoms below 4000 m, consistent with the recognised protective effect of slow rate of ascent; at 3500-4000 m all showed a sharp fall on O2sat and above 4500 m symptoms arose unpredictably. Secondly, hourly blood pressure monitoring showed no altitude effect below 3500 m, but above 5000 m a marked yet asymptomatic rise with delayed and prolonged peak. CONCLUSION: There may be a critical altitude above which extra vigilance is required; blood pressure here needs further research.

Sleeping altitude and sudden cardiac death.

BACKGROUND: Mountain activities characterized by strenuous exercise in a hypoxic setting place unique demands on the body. The mortality rate associated with mountain activities is high, with sudden cardiac death (SCD) representing the most frequent of all nontraumatic deaths. We evaluated the possible effect of acclimatization in reduction of SCD during high-altitude sojourns. METHODS: This was a retrospective cohort study involving all deaths (N = 559) that occurred during mountain activities in Austria from 1985 through 1993. Baseline patient demographics, cardiovascular comorbidities, smoking history, family history of SCD, sleeping altitude, annual mountaineering frequency, and physical activity on the day of SCD were included in a questionnaire previously used in a pilot study. RESULTS: Data from 301 of 599 individuals without prespecified exclusions were available for analysis (79% of eligible cohort). Sudden cardiac deaths happened mostly around noon (29%), and mean altitude at which SCDs occurred was 1,710 ± 501 m. When sleeping altitude was divided into quartiles (<700 m, 700-999 m, 1,000-1,299 m, and >1,299 m), the odds ratio for SCD on the first day at altitude when sleeping below 700 m was 5.7 (95% CI 2.8-11.6) as compared with sleeping above 1,299 m. CONCLUSION: For males >34 years, those with history of coronary artery disease and/or prior infarction, and those unaccustomed to physical activity at altitude, sleeping at moderate altitude before exercising at altitude may reduce the risk of SCD.

No todo es diversión: papiledema y montana rusa / Not everything is fun: papilledema and roller coaster

Presentamos el caso de una paciente de 30 años de edad previamente saludable, quien desarrolló luego de numerosos viajes en una montaña rusa un hematoma subdural espontáneo y un higroma contralateral. La estroma velocidad y despliegue de fuerza G, la sucesión de momentos de aceleración y desaceleración, los bruscos movimientos cefálicos con tironeo lateral del cerebro y el número de veces que permitió el viaje, constituyeron un riesgo significativo de ruptura de venas puente, siendo posible que las reiteradas caídas de una boya remolcada hayan constituido el último trauma y desencadenamiento final

We present the case of a 30-year-old previously healthy patient, who developed ofter numerous trips on a roller coaster a spontaneous hematoma subdural and a contralateral hygroma. Extreme speed and G-force deployment, the succession of moments of acceleration and deceleration, sudden cephalic movements with snarling side of the brain and the number of times that he repeated the trip, they constituted a significant risk of rupture of veins bridge, being possible that repeated falls from a towed buoy have produced the latest trauma and final trigger

Living at altitude adversely affects survival among patients with a Fontan procedure.

OBJECTIVES: This study sought to determine whether survival in this cohort of patients was adversely affected by increased residential altitude. BACKGROUND: The success of the Fontan procedure depends in large part on low pulmonary vascular resistance (PVR). Factors that increase PVR, including an increase in residential altitude, may adversely affect long-term outcome. Higher altitude has been shown to affect functional well-being in patients with a Fontan circulation. METHODS: Databases from a tertiary cardiac care center in the Intermountain West (elevation 5,000 feet) were analyzed for patients born with single-ventricle anatomy who would now be of adult age. Complete data were then collected on all identified patients who subsequently underwent the Fontan operation. Correlates of, and time to, adverse outcome, defined as death, cardiac transplantation, or clinical decompensation requiring a move to sea level, were determined. RESULTS: Of 149 patients with single-ventricle anatomy, 103 underwent the Fontan procedure, with 70 surviving to adulthood at moderate altitude. Adverse outcome occurred in 55, with death in 24 (23%), cardiac transplantation in 18 (17%), and clinical decompensation requiring move to sea level in 13 (13%). There was no relationship between type, age at, or era of Fontan procedure and long-term outcome. Correlates of long-term, transplant-free survival at moderate altitude included lower residential altitude (4,296 vs. 4,637 feet, p < 0.001), and lower pulmonary artery pressures before the Fontan procedure (13 vs. 15 mm Hg, p = 0.01), and after (14 vs. 18 mm Hg, p = 0.01). CONCLUSIONS: Long-term outcome after the Fontan procedure is adversely impacted by higher residential altitude.

Mountain mortality: a review of deaths that occur during recreational activities in the mountains.

The growing popularity of activities such as hiking, climbing, skiing and snowboarding has ensured that the number of visitors to mountain environments continues to increase. Since such areas place enormous physical demands on individuals, it is inevitable that deaths will occur. Differences in the activities, conditions and methods of calculation make meaningful mortality rates difficult to obtain. However, it is clear that the mortality rate for some mountain activities is comparable to hang gliding, parachuting, boxing and other pastimes that are traditionally viewed as dangerous. Deaths in the mountains are most commonly due to trauma, high altitude illness, cold injury, avalanche burial and sudden cardiac death. This review describes the mortality rates of those who undertake recreational activities in the mountains and examines the aetiology that lies behind them.

Mortality on Mount Everest, 1921-2006: descriptive study.

OBJECTIVE: To examine patterns of mortality among climbers on Mount Everest over an 86 year period. DESIGN: Descriptive study. SETTING: Climbing expeditions to Mount Everest, 1921-2006. PARTICIPANTS: 14,138 mountaineers; 8030 climbers and 6108 sherpas. MAIN OUTCOME MEASURE: Circumstances of deaths. RESULTS: The mortality rate among mountaineers above base camp was 1.3%. Deaths could be classified as involving trauma (objective hazards or falls, n=113), as non-traumatic (high altitude illness, hypothermia, or sudden death, n=52), or as a disappearance (body never found, n=27). During the spring climbing seasons from 1982 to 2006, 82.3% of deaths of climbers occurred during an attempt at reaching the summit. The death rate during all descents via standard routes was higher for climbers than for sherpas (2.7% (43/1585) v 0.4% (5/1231), P<0.001; all mountaineers 1.9%). Of 94 mountaineers who died after climbing above 8000 m, 53 (56%) died during descent from the summit, 16 (17%) after turning back, 9 (10%) during the ascent, 4 (5%) before leaving the final camp, and for 12 (13%) the stage of the summit bid was unknown. The median time to reach the summit via standard routes was earlier for survivors than for non-survivors (0900-0959 v 1300-1359, P<0.001). Profound fatigue (n=34), cognitive changes (n=21), and ataxia (n=12) were the commonest symptoms reported in non-survivors, whereas respiratory distress (n=5), headache (n=0), and nausea or vomiting (n=3) were rarely described. CONCLUSIONS: Debilitating symptoms consistent with high altitude cerebral oedema commonly present during descent from the summit of Mount Everest. Profound fatigue and late times in reaching the summit are early features associated with subsequent death.

Clinical features of patients with severe altitude illness in Nepal.

BACKGROUND: Trekking in Nepal is a popular adventure travel activity involving more than 80,000 people of all ages annually. This study focuses on the demographic characteristics and clinical course of altitude illness patients evacuated to Kathmandu and estimates the rates of evacuation in different regions of Nepal. METHODS: During the years 1999 to 2006, all patients who presented with altitude illness to the CIWEC clinic in Kathmandu were evaluated and included in the study if the final diagnosis was compatible with high-altitude cerebral edema (HACE), high-altitude pulmonary edema (HAPE), or acute mountain sickness (AMS). Altitude illness-related deaths were reported according to death certificates issued by selected embassies in Kathmandu. RESULTS: A total of 406 patients were evaluated, among them 327 retrospectively and 79 prospectively. HACE was diagnosed in 21%, HAPE in 34%, combined HAPE and HACE in 27%, and AMS in 18%. Mean patient age was older than trekker controls (44 +/- 13.5 vs 38.6 +/- 13.9 y, p < 0.0001). Everest region trekkers were more likely to be evacuated for altitude illness than trekkers in other regions. The estimated incidence of altitude illness-related death was 7.7/100,000 trekkers. Most altitude illness symptoms resolved completely within 2 days of evacuation. CONCLUSIONS: Altitude illness that results in evacuation occurs more commonly among trekkers in the Everest region and among older trekkers. The outcome of all persons evacuated for altitude illness was uniformly good, and the rate of recovery was rapid. However, the incidence of altitude illness-related death continued to rise over past decade.

[Risks in mountaineering and trekking]. / Risiken beim Bergwandern und Trekking.

Mass tourism in the mountains is on the increase. The climbers often do not know much about the possible risks which include death, invalidity and sickness. In this article, risks such as AMS (acute mountaine sickness), HACE (high altitude cerebral edema) and HAPE (high altitude pulmonale edema) are shown. These facts should be taken into account for risk assessment in the private insurance industry.

Mountaineering in thin air. Patterns of death and of weather at high altitude.

An 8000-m peak bring challenges of extremes of hypoxia and weather as well as the normal hazards of climbing itself. These challenges have taken a severe toll: 604 mountaineers have died on those great peaks since 1950. Little is known about whether mountain height, use of supplemental oxygen, or team size might influence rates of death or of success. However, such information may provide insights not only to our understanding of the limits of human performance, but also to mountaineers in making decisions on these peaks. We present several examples from a research program that is attempting to analyze factors that potentially influence success or death rates on the 8K peaks. (1) Apparent risk of death in the notorious Khumbu Icefall on Mt. Everest has declined dramatically in recent years. This decline could reflect improved route finding and technique, but might also reflect climate warming, which has caused the Khumbu glacier to shrink and slow in recent decades. (2) Risk of death during descent from an 8000-m peak increases with the height of the peak. (3) Risk of death during descent from the summit of Everest or of K2 is elevated for climbers not using supplemental oxygen. (4) We outline some new studies that are exploring how convective heat loss, which influences wind chill, changes with altitude as well as the incidence of storms: both factors will impact the probability success and death of Himalayan mountaineers.