Recommendations for resuscitation after ascent to high altitude and in aircrafts

Human exposure to high altitude is increasing, through inhabitation of areas of high altitude, expansion of tourism into more remote areas, and air travel exposing passengers to typical altitudes equivalent to 8005 ft (2440 m). With ascent to high altitude, a number of acute and chronic physiological changes occur, influencing all systems of the human body. When considering that cardiac arrest is the second most common cause of death in the mountains and that up to 60% of the elderly have significant heart disease or other health problems, these changes are of particular importance as they may have a significant impact on resuscitation efforts. Current guidelines for resuscitation lack specific recommendations regarding treatment of cardiac arrest after ascent to high altitude or in aircraft. Therefore, we performed a comprehensive search in PubMed, CINAHL, Cochrane Library, and Scopus databases for studies relevant to resuscitation at high altitude. As no randomized trials evaluating the effects of physiological changes after ascent to high altitude on cardiopulmonary resuscitation were identified, our search was expanded to include all studies addressing important aspects on high altitude physiology which could have a potential impact on the resuscitation of cardiac arrest victims. The aim of this review is to discuss the major physiological changes occurring after ascent to high altitude and their potential effects on cardiopulmonary resuscitation. Based on the available data, specific suggestions are proposed regarding resuscitation at high altitude.