High-altitude illnesses: Physiology, risk factors, prevention, and treatment

Abstract

High-altitude illnesses encompass the pulmonary and cerebral syndromes that occur in non-acclimatized individuals after rapid ascent to high altitude. The most common syndrome is acute mountain sickness (AMS) which usually begins within a few hours of ascent and typically consists of headache variably accompanied by loss of appetite, nausea, vomiting, disturbed sleep, fatigue, and dizziness. With millions of travelers journeying to high altitudes every year and sleeping above 2,500 m, acute mountain sickness is a wide-spread clinical condition. Risk factors include home elevation, maximum altitude, sleeping altitude, rate of ascent, latitude, age, gender, physical condition, intensity of exercise, pre-acclimatization, genetic make-up, and pre-existing diseases. At higher altitudes, sleep disturbances may become more profound, mental performance is impaired, and weight loss may occur. If ascent is rapid, acetazolamide can reduce the risk of developing AMS, although a number of high-altitude travelers taking acetazolamide will still develop symptoms. Ibuprofen can be effective for headache. Symptoms can be rapidly relieved by descent, and descent is mandatory, if at all possible, for the management of the potentially fatal syndromes of high-altitude pulmonary and cerebral edema. The purpose of this review is to combine a discussion of specific risk factors, prevention, and treatment options with a summary of the basic physiologic responses to the hypoxia of altitude to provide a context for managing high-altitude illnesses and advising the non-acclimatized high-altitude traveler.

Physiochemical and Sensory Evaluation of Developed Herbal Bars

“…A person suffers from various symptoms of Headache, Fatigue, Gastrointestinal disorders, Insomniac and disorientation (Taylor, 2011).…”

Acute mountain sickness

“…By inhibiting carbonate anhidrosis in kidneys, acetazolamide induces metabolic acidification, which results in quicker reactions of chemoreceptors to hypoxia associated with high altitudes. Moreover, the drug has been shown to stimulate ventilation by decreaseing the concentration of bicarbonates reducing pH in the cerebrospinal fluid [5]. The most common side effects of the drug include nausea and lack of appetite.…”

“…Such doses were continued for three subsequent days and gradually reduced during the next days [6]. At present, dexamethasone is recommended during evacuation to improve cooperation or when the descent is impossible [5]. Considering numerous adverse side effects, the administration of the drug is presently restricted and it is replaced by acetazolamide or combination of both drugs [13].…”

“…The findings of the study carried out in a 21-year-old healthy skier and subsequently in a large population of soldiers stationed in Himalayas were one of the sources to determine the diagnostic criteria of high altitude illnesses [1]. The criteria were established in 1991 by the group of experts and named the Lake Louis Score [1,4,5].…”

Transient Non-Suppressible Cough at Altitude Occurring With Cessation of Exercise

“…As an individual ascends to ever increasing heights, the risk of high-altitude illnesses including the potentially fatal syndrome of high-altitude pulmonary edema (HAPE) also increases. Early diagnosis of HAPE may be difficult since many of the early symptoms (shortness of breath, tachypnea, tachycardia, reduced arterial saturation, fatigue and dry cough) are often present in unaffected climbers at higher altitudes, particularly in cold, dry or dusty environments [1][2][3]. Nevertheless, early diagnosis is critical.…”