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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Which is a feature of high altitude pulmonary edema
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The correct answer is  Ans. is 'b' i.e. associated with pulmonary hypertension [Ref: Harrison 17/e, p 1707 (16/e, p 1617); ACP Medicine ' (2006); Ganong 22/e, p 685; www.emedicine.com/MED/topicl956.htmJHigh altitude pulmonary edema (HAPE) is a life-threatening form of non-cardiogenic pulmonary edema that occurs in otherwise healthy mountaineers at altitudes above 2,500 meters (8,200 feet).HAPE belongs to a spectrum of High altitude illness. HAPE and High Altitude Cerebral Edema are most ominous forms of High altitude illness. Milder forms are - acute mountain sickness, retinal hemorrhages, and peripheral edema.The initial insult that causes HAPE is excessive hypoxia caused by the lower air pressure at high altitudes. The mechanisms by which this shortage of oxygen causes HAPE are poorly understood, but two processes are believed to be important:Increased pulmonary arterial and capillary pressures (pulmonary hypertension) secondary to hypoxic pulmonary vasoconstrictionAn idiopathic non-inflammatory increase in the permeability of the vascular endothelium.* Treatment includesDescent from altitude,BedrestOxygen " Inhaled nitric oxideNifedipine.