Olongapo City – In the published manual of the WHO entitled “Treatment of Diarrhea” (2005), fluid deficits in dehydration and response to therapy need not be calculated using laboratory values but rather by straightforward physical examination.
Diarrhea with NO SIGNS of dehydration can have a fluid deficit of no greater than 5% or 50 ml per kg body weight. Thus a 15 kg child with diarrhea who is alert, drinks normally, and has normal physical exam is estimated to have at most 750ml of fluid deficit and correction of that deficit by increased oral fluid intake or ORS can be beneficial.
Diarrhea with SOME SIGNS of dehydration can have a fluid deficit of 5-10% or 50-100 ml per kilogram of body weight. For a 15 kg child with diarrhea who is restless/irritable, has sunken eyes, thirsty/drinks eagerly, and/or skin pinch that goes back slowly, his fluid deficit is estimated to be in the 750-1500 ml range. The patient should be weighed to detect clinical response as most patients begin to lose weight at this stage of dehydration. ORS, continued feeding, and zinc supplementation is recommended.
Diarrhea with SEVERE SIGNS of dehydration can have a fluid deficit of more than 10% or greater than 100 ml per kilogram body weight. Thus the same 15 kg child above, should he become lethargic or unconscious, have sunken eyeballs, drinks poorly or not able to drink, and/or with a very slow (>2 sec) skin pinch over the abdomen, is likely to have a deficit of more than 1500 ml! This patient should be admitted. IV fluids and ORS are an emergency measure. Death follows if there is no immediate fluid replacement in 24 hours.
These fluid deficit estimation can be used in many etiologies of dehydration such as hyperemesis and severe exercise. Reference used in this article was provided by WHO and can be downloaded from this link:
Dr. Mella is currently the head of the Committee on Diarrheal Diseases, Olongapo City Health Office