Glomerular filtration rate estimates decrease during high altitude expedition but increase with Lake Louise acute mountain sickness scores

AIM: Acute mountain sickness (AMS) can result in pulmonary and cerebral oedema with overperfusion of microvascular beds, elevated hydrostatic capillary pressure, capillary leakage and consequent oedema as pathogenetic mechanisms. Data on changes in glomerular filtration rate (GFR) at altitudes above 5000 m are very limited. METHODS: Thirty-four healthy mountaineers, who were randomized to two acclimatization protocols, undertook an expedition on Muztagh Ata Mountain (7549 m) in China. Tests were performed at five altitudes: Zurich pre-expedition (PE, 450 m), base camp (BC, 4497 m), Camp 1 (C1, 5533 m), Camp 2 (C2, 6265 m) and Camp 3 (C3, 6865 m). Cystatin C- and creatinine-based (Mayo Clinic quadratic equation) GFR estimates (eGFR) were assessed together with Lake Louise AMS score and other tests. RESULTS: eGFR significantly decreased from PE to BC (P < 0.01). However, when analysing at changes between BC and C3, only cystatin C-based estimates indicated a significant decrease in GFR (P = 0.02). There was a linear decrease in eGFR from PE to C3, with a decrease of approx. 3.1 mL min(-1) 1.73 m(-2) per 1000 m increase in altitude. No differences between eGFR of the two groups with different acclimatization protocols could be observed. There was a significant association between eGFR and haematocrit (P = 0.01), whereas no significant association between eGFR and aldosterone, renin and brain natriuretic peptide could be observed. Finally, higher AMS scores were significantly associated with higher eGFR (P = 0.01). CONCLUSIONS: Renal function declines when ascending from low to high altitude. Cystatin C-based eGFR decreases during ascent in high altitude expedition but increases with AMS scores. For individuals with eGFR <40 mL min(-1) 1.73 m(-2), caution may be necessary when planning trips to high altitude above 4500 m above sea level.

Internationale Kontrolle lokaler Verwaltung in einer Konfliktregion. Das Experiment „Freie Stadt Danzig“ (1920-1939)

The Free City of Danzig was founded by the Allies after World War One to settle the conflict between Poles and Germans as to which territory the town belonged. The League of Nations was designated to be the guarantor of its status. British and American experts and policy advisors saw it as an experiment on the way to new forms of statehood, by means of which nationalism as the founding principle of territorial entities could be overcome. However, the „Free City“ status was rejected by both the city’s inhabitants and German and Polish government agencies, with the result that the League and its local representative, the High Commissioner, were constantly confronted with difficulties in the interpretation of the international treaties and conventions relating to Danzig. In addition, hardly anyone in Danzig, Germany or Poland was interested in the economic and financial situation of the Free City, but were more interested in winning political battles than in the well-being of the city and its inhabitants. As a result, the situation in Danzig became more and more hopeless. The city became increasingly dependent on (illegal) German subsidies, while the High Commissioners generally cared more about their own prestige and that of their home countries than about the interests of the League of Nations. But as no political means of modifying the city’s status had been provided for, nothing changed formally in Danzig until Germany started the Second World War and annexed the city in September 1939. In retrospect, the international control of local government could not contribute to a long-term solution for Danzig. It merely postponed its violent solution for twenty years.