Background

Acute pulmonary edema, a potentially fatal condition, represents a major complication of so-called “Acute mountain sickness ” (AMS), that may also involve cerebral edema. Acute mountain sickness is a clinical syndrome usually character-ized by the presence of headache, nausea, exces-sive fatigue, irritability and insomnia [1]. The clin-ical picture of high altitude pulmonary edema (HAPE), as it appears in subjects exposed to alti-tude, is characterized by clinical signs, serious hy-poxemia, increase in the alveolar-arterial oxygen gradient, pulmonary hypertension, and alveolar edema on chest radiography. The syndrome spec-trum also includes less serious and subclinical forms. More than 25 years ago a paper on the Lancet examined the incidence and the relevance of AMS studying 278 unacclimatised hikers at 4,243 me-tres altitude in the Himalayas of Nepal (Asia). AMS global incidence was 53%, and it was higher in younger subjects, in those who had performed a more rapid climb and in those who had had a smaller number of acclimatisation nights. Seven individuals with AMS suffered a pulmonary ede-ma and 5 had a cerebral edema; among these 12 people, 9 had spent only one night in altitude. The Authors concluded suggesting, so as to prevent and limit HAPE, a slow and fractioned ascent, careful attention to clinical signs and symptoms, and a rapid descent in order to avoid the develop-ment of the clinical picture [1]. Historical survey Altitude medicine is a discipline with defined historical root. Already in 1890 Joseph Vallot (1854-1925) built an observatory on Mont Blanc (Alps, Europe), at an altitude of 4,358 metres, to act as a centre for astronomy, meteorology, geolo-gy, botanics, physiology and medical studies. Dur-ing the preparation for the construction of a new observatory on Mont Blanc in 1891 (by Xaver Im-A historical perspective on high altitude pulmonary edema Storia ed attualità dell’edema polmonare acuto da alta quot