Mahalanabis D
Society for Applied Studies, Calcutta.
Indian J Med Res. 1996 Jul;104:115-24.
For more than two decades, WHO and UNICEF have recommended a single formulation of oral rehydration salts (ORS) solution based on glucose and three salts. This product has proven safe and highly effective in treating and preventing dehydration from diarrhoea of all causes and in all age groups in worldwide use and has substantially contributed to the saving of lives in developing countries. However, oral rehydration therapy (ORT) using this formulation does not make diarrhoea any less severe or stop it sooner; which is what is required. During the last 16 yr numerous studies were undertaken to develop an improved ORS that could, in addition to being effective therapy to treat and prevent dehydration, reduce severity and duration of diarrhoea. Controlled clinical trials of ORS formulations containing aminoacids showed that, while they were substantially more absorption efficient in cholera, they were no more effective than standard ORS in infants and children with noncholera diarrhoea; none of these formulations are considered a suitable replacement for standard ORS. Rice-based ORS, in a number of studies, was found superior to standard ORS in adults and children with cholera and its use in such patients is recommended. However, the benefit of using rice-based ORS in infants and small children was either small or insignificant compared to standard ORS, when feeding during ORT was actively pursued. Rice-based ORS was also as effective as standard ORS in infants under 6 months of age and in severely malnourished children. Recently, several studies evaluated glucose-based ORS made hypoosmolar by reducing the concentration of glucose and sodium (with glucose concentration of 75-90 and sodium 60-75 mmol/l and osmolarity of 225-250 mosm/l). These hypoosmolar solutions showed clinically significant benefit in reducing the severity of diarrhoea and the need for supplemental i.v. therapy in infants and children. In limited studies, similar results were obtained in adults with cholera; however, marked hyponatraemia was noted in a small proportion of high purging cholera patients. Two multicentric trials of a hypoosmolar solution, one in adults with cholera and one in children with non-cholera diarrhoea, are ongoing; results of these trials should help us decide whether such a solution could be a practical replacement for standard ORS.
二十多年来，世界卫生组织（WHO）和联合国儿童基金会（UNICEF）一直推荐使用一种基于葡萄糖和三种盐类的单一配方口服补液盐（ORS）溶液。该产品在全球范围内被用于治疗和预防各种原因引起的腹泻导致的脱水，已证明其安全性高且效果显著，为发展中国家挽救生命做出了重大贡献。然而，使用这种配方进行口服补液疗法（ORT）并不能减轻腹泻的严重程度，也不能更快地止泻，而这才是我们所需要的。在过去的16年里，人们进行了大量研究，以开发一种改进的ORS，使其除了能有效治疗和预防脱水外，还能减轻腹泻的严重程度并缩短腹泻持续时间。含氨基酸的ORS配方的对照临床试验表明，虽然它们在霍乱治疗中吸收效率显著更高，但在患有非霍乱腹泻的婴幼儿中并不比标准ORS更有效；这些配方均未被视为标准ORS的合适替代品。在多项研究中，发现米基ORS在患有霍乱的成人和儿童中优于标准ORS，因此建议在这类患者中使用。然而，在积极进行ORT喂养时，与标准ORS相比，米基ORS在婴幼儿中的益处要么很小，要么不显著。米基ORS在6个月以下婴儿和重度营养不良儿童中与标准ORS同样有效。最近，几项研究评估了通过降低葡萄糖和钠浓度（葡萄糖浓度为75 - 90 mmol/l，钠浓度为60 - 75 mmol/l，渗透压为225 - 250 mosm/l）制成的低渗葡萄糖基ORS。这些低渗溶液在减轻婴幼儿腹泻严重程度和减少补充静脉输液治疗需求方面显示出显著的临床益处。在有限的研究中，患有霍乱的成人也得到了类似结果；然而，一小部分严重腹泻的霍乱患者出现了明显的低钠血症。正在进行两项关于低渗溶液的多中心试验，一项针对患有霍乱的成人，另一项针对患有非霍乱腹泻的儿童；这些试验的结果应有助于我们确定这种溶液是否可以实际替代标准ORS。
