Companion Rescue and Risk Management of Trekkers on the Everest Trek, Solo Khumbu Region, Nepal

Background: Trekking to high-altitude locations presents inherent health-related hazards, many of which can managed with specific first aid (FA) training. This study evaluates the trip preparation, FA knowledge, and FA self-assessment of trekkers (organized by tour operators vs. individually planned tours). Data obtained shall be used for specific FA trip preparation and management of emergencies en route for this population. Methods: A total of 366 trekkers on the Everest Base Camp Trek, Nepal, were interviewed using a questionnaire specifically designed to evaluate their FA knowledge and management of emergencies. Data evaluation was performed using descriptive statistics. Results: A total of 40.5% of trekkers experienced at least one medical incident during their trip, of which almost 50% were due to acute mountain sickness (AMS). There was more AMS in commercially organized groups than in individually planned ones (55% vs. 40%). For more than 50%, no medical care was available during their trip. A total of 80% could answer only 3/21 FA questions completely correctly. Only 1% showed adequate knowledge concerning FA strategies. A total of 70% were willing to enroll in an FA class specialized towards the needs of trekkers. Conclusions: The importance of high-altitude FA knowledge and trip preparation is widely underestimated. There is an unmet demand amongst trekkers for specific wilderness FA classes

The impact of sleeping in an elevated upper body position during acclimatization to high altitude on acute mountain sickness and pulmonary artery systolic pressure

Background: The effect of sleeping positions during acclimatization to high altitude on Acute Mountain Sickness (AMS) and High Altitude Pulmonary Edema (HAPE) is unknown. We tested whether sleeping with the upper body raised by 5° reduces prevalence and severity of symptoms of AMS as well as of elevated pulmonary artery systolic pressure (PASP) values as a risk factor of HAPE. Methods: Randomly assigning trekking tourist volunteers n = 44 (25 m, 19 f; mean age 42.9 yr) sleeping at 4280 m or 5170 m to the experimental group (upper body elevated by 5°), or to the control group. After exclusion of other reasons for AMS-like symptoms those assumed to be related to AMS were rated by Lake Louise Score questionnaire in the evening and the following morning of the study. Transthoracic echocardiography was performed on both occasions to estimate PASP. Results: In the study group, symptoms of AMS were significantly reduced in younger subjects (p = 0.021), prevalence of AMS was reduced in women (p = 0.156), and PASP values were significantly reduced in older subjects and men (p = 0.032; p = 0.031 respectively). Conclusion: Results suggest that sleeping with the upper body in elevated position during a high altitude ascent may benefit those suffering from AMS or at risk of HAPE due to elevated PASP values

Variables Influencing the Pressure and Volume of the Pulmonary Circulation as Risk Factors for Developing High Altitude Pulmonary Edema (HAPE)

Background: At altitudes above 2500 m, the risk of developing high altitude pulmonary edema (HAPE) grows with the increases in pulmonary arterial pressure. HAPE is characterized by severe pulmonary hypertension, though the incidence and relevance of individual risk factors are not yet predictable. However, the systolic pulmonary pressure (SPAP) and peak in tricuspid regurgitation velocity (TVR) are crucial factors when diagnosing pulmonary hypertension by echocardiography. Methods: The SPAP and TVR of 27 trekkers aged 20–65 years en route to the Solu Khumbu region of Nepal were assessed. Echocardiograph measurements were performed at Lukla (2860 m), Gorak Shep (5170 m), and the summit of Kala Patthar (5675 m). The altitude profile and the participants’ characteristics were also compiled for correlation with the measured data. Results: The results showed a highly significant increase in SPAP and TVR after ascending Kala Patthar. The study revealed a lower increase of SPAP and TVR in the group of older participants, although the respective initial measurements at Gorak Shep were significantly higher for this group. A similar finding occurred in those using Diamox® as prophylaxis. There was an inverse relationship between TVR and SPAP, the peripheral capillary oxygen saturation, and heart rate. Conclusions: The echocardiograph results indicated that older people are an at-risk group for developing HAPE. A conservative interpretation of the basic tactical rules for altitudes should be followed for older trekkers or trekkers with known problems of altitude acclimatization (“slow acclimatizer”) as SPAP elevates with age. The prophylactic use of Acetazolamide (Diamox®) should be avoided where not necessary for acute medical reasons. Acetazolamide leads to an increase of SPAP, and this may potentially enhance the risk of developing HAPE. Arterial oxygen saturation measurements can provide an indicator for the self-assessment for the risk of developing HAPE and a rule of thumb for the altitude profile, but does not replace a HAPE diagnosis. Backpack weight, sex, workload (actual ascent speed), and pre-existing diseases were not statistically significant factors related to SPAP and TVR (p ≤ 0.05)

Cardiovascular Risk Profiles and Pre-Existing Health Conditions of Trekkers in the Solu-Khumbu Region, Nepal

Background: High-altitude tourist trekking continues to grow in popularity on the Everest Trek in Nepal. We examined which pre-existing cardiovascular and health conditions these global trekkers had and what health issues they encountered during the trek, be it exacerbations of pre-existing conditions, or new acute ones. Method: Trekkers (n = 350) were recruited from guesthouses along the Everest Trek, mostly at Tengboche (3860 m). After completing a questionnaire on their health and travel preparation, they underwent a basic physical examination with an interview. Results: Almost half (45%) had pre-existing conditions, mostly orthopaedic and cardiovascular diseases. The average age was 42.7 years (range 18–76). The average BMI was 23.4 kg/m2, but 21% were overweight. A third were smokers (30%), and 86% had at least one major cardiovascular risk factor. A quarter (25%) were suffering from manifest acute mountain sickness (AMS), and 72% had at least one symptom of AMS. Adequate pre-travel examination, consultation, and sufficient personal preparation were rarely found. In some cases, a distinct cardiovascular risk profile was assessed. Hypertensive patients showed moderately elevated blood pressure, and cholesterol levels were favourable in most cases. No cardiovascular emergencies were found, which was fortunate as timely, sufficient care was not available during the trek. Conclusion: The results of earlier studies in the Annapurna region should be revalidated. Every trekker to the Himalayas should consult a physician prior to departure, ideally a travel medicine specialist. Preventative measures and education on AMS warrant special attention. Travellers with heart disease or with a pronounced cardiovascular risk profile should be presented to an internal medicine professional. Travel plans must be adjusted individually, especially with respect to adequate acclimatisation time and no physical overloading. With these and other precautions, trekking at high altitudes is generally safe and possible, even with significant pre-existing health conditions. Trekking can lead to invaluable personal experiences. Since organized groups are limited in their flexibility to change their itinerary, individual trekking or guided tours in small groups should be preferred