Lessons Learned on a High-Altitude Expedition to Mount Kilimanjaro.

High-altitude expeditions expose teams to particular medical, environmental, and social challenges that can have unintended and severe consequences for crew members. In June 2017, the 9-d Equal Playing Field (EPF) expedition to Mount Kilimanjaro to set a world record for the highest-altitude soccer match ever played demonstrated the variety of challenges that may arise during these types of trips. This trip included a full-length soccer match at 5714 m (18,746 ft), leading to additional challenges for expedition members participating in the athletic event. The EPF medical team identified the challenges that occurred during the expedition and documented the methods used to resolve these challenges in real time. From the challenges faced during the expedition, we describe the lessons learned for future expeditions to Mount Kilimanjaro and other high-altitude environments. Challenges arose with medical tent visibility, medical disqualification, underreporting of medical events, and acute pain management, while anticipated challenges with interpersonal conflict did not occur. The rigorous preparation and anticipation by the EPF medical team prior to expedition departure may have helped mitigate this conflict as well as prevented unintended severe medical events from occurring.