High Altitude Mountaineering after Lung Transplantation - Jebel Toubkal Peak 4167m

Purpose After successful lung transplantation, patients can potentially reach same strength and endurance as healthy individuals. Although high-altitude trekking has been reported after LuTX, data on the patient's physiological adaptation during prolonged exercise in a reduced oxygen environment remains scarce. Methods In September 2019, 14 lung transplanted patients and their accompanying doctors, climbed Mount Jebel Toubkal (4167 m; 13 671 ft), the highest peak in North Africa, High Atlas, Morocco. Participants had regular cardiopulmonary exams (lung function, polysomnography, echocardiography) as well as blood sampling (capillary blood gasses, lactate, creatinine) throughout the expedition up to 3145 m (10 318 ft). Results Patients (♀: n=3 | ♂: n=11) had a median age of 42.1 years (24.8-65.2). Their underlying diagnoses were CF (n=10), Emphysema (n=2), IPF (n=1) and PH (n=1). Median time from LuTX to this expedition was 4.1 Years (1.7-17.6). Controls (♂: n=4) were 31.3 (29.3-46.7) years old. Over 7 days, participants hiked a distance of 81km (50.3 mi) with a cumulative elevation gain of 5496 m (18,031 ft.) vertical distance. Eleven Patients (78.6%) reached the summit whereas three patients had to abort because of altitude sickness (n=1 on day 1 at 2431m) or physical exhaustion (n=2 on day 3 at 3124m and day 6 at 3800m). Blood gas analysis and vital signs did not differ significantly between the patients and four healthy controls (pO2: 59.1 ±8.9 vs. 61.8 ±14.4 mmHg | pCO2: 29.8 ±1.5 vs. 29.8 ±0.5 mmHg | lactate 0.82 vs 0.83 mmol/l). Creatinine was significantly higher in transplanted patients (1.87 vs. 0.97 mg/dl; p=0.025). Conclusion Although technically challenging, medical monitoring of lung transplanted patients is feasible during high altitude hiking. In carefully selected athletic LuTX patients, gas exchange and metabolism didn't differ compared to healthy adults.