Dehydration is when body water content is reduced causing dry skin, headaches, sunken eyes, dizziness, confusion, and sometimes death. Children with dehydration due to gastroenteritis need rehydrating either by liquids given by mouth or a tube through the nose, or intravenously. The review of 17 trials (some funded by drug companies) found that the trials were not of high quality; however the evidence suggested that there are no clinically important differences between giving fluids orally or intravenously. For every 25 children treated with fluids given orally, one child would fail and require intravenous rehydration. Further, the results for low osmolarity solutions, the currently recommended treatment by the World Health Organization, showed a lower failure rate for oral rehydration that was not significantly different from that of intravenous rehydration. Oral rehydration should be the first line of treatment in children with mild to moderate dehydration with intravenous therapy being used if the oral route fails. The evidence showed that there may be a higher risk of paralytic ileus with oral rehydration while intravenous therapy carries the risk of phlebitis (ie inflammation of the veins).
Hartling, L.; Bellemare, S.; Wiebe, N.; Russell, K.F.; Klassen, T.P.; Craig, W.R. Oral versus intravenous rehydration for treating dehydration due to gastroenteritis in children. Cochrane Database of Systematic Reviews (2006) (Issue 3) Art. No.: CD004390. [DOI: 10.1002/14651858.CD004390.pub2]