摘要:

Astronauts lose body mass when exploring space. The mechanism was considered to be an upward fluid shift inducing diuresis and natriuresis (the Henry-Gauer mechanism) during the first few days in microgravity. However, recent space missions have shown that neither diuresis nor natriuresis occurs in space missions. In contrast, a sodium-retaining status was shown, which led to positive metabolic sodium balances without fluid retention. Energy intake was consistently reduced whereas energy needs were unchanged, resulting in a negative energy balance of 20%. The reasons for this are many, although proper studies on appetite regulation have not been carried out. Despite numerous countermeasures, bone mass is lost in microgravity situations. These are body composition changes that need to be challenged before humans can be sent to space for extra-long missions.

ISSN:1363-1950    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

In the effort to improve the long-term outcome in critically ill patients, the utilization of anabolic agents, such as human recombinant growth hormone, has been proposed in order to reduce catabolism and improve nutritional status. A recent multicentre study regarding the use of human recombinant growth hormone in intensive care unit patients showed an unexpected increase in the mortality rate in human recombinant growth hormone-treated patients. This finding is in contrast with previous literature data reporting either no differences or an even lower mortality rate with the administration of human recombinant growth hormone. This review evaluates the possible reasons for this dramatic difference in outcomes between the multicentre study and the existing literature. Articles dealing with human recombinant growth hormone administration either in intensive care unit patients (n= 26) or in postoperative patients (n= 16) have been reviewed. Our analysis suggests that the low caloric intake given to patients enrolled in the multicentre study might have been inadequate to compensate for the hypermetabolism of these patients, and could not support the prolonged and delayed administration of high doses of human recombinant growth hormone. Whether the beneficial metabolic effects of human recombinant growth hormone translate into better clinical outcomes deserves further investigation. In addition, the careful selection of patients to be treated, and close monitoring of both the adequacy of caloric support and modality of human recombinant growth hormone administration would favour the safety of human recombinant growth hormone utilization in critical care settings.

ISSN:1363-1950    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:1363-1950    

出版商:OVID    

年代:2001

数据来源: OVID