Fluid balance range for human

I am working on clinical data analysis with patients from icu who are mechanically ventilated and in ICU for 4 or more days.

Currently I tried to calculate their fluid balance based on the input and output items.

I summed up all their input and output items and finally did a subtraction to find the fluid balance.

Can you let me know if there is any range for fluid balance? I mean is it something like -5000 to +9000?

Can you please provide me the range which is possible?

For example a range like -30000 to +45000 is even possible?

• I don't understand what you're asking. Are you looking for normal ranges or acceptable ranges or what? The necessary fluid intake is going to depend on many individual patient factors but in general input needs to match output. If there's a large difference over a prolonged period the patient would eventually experience electrolyte disturbances. – Carey Gregory Jan 1 '20 at 16:57
• Am. Looking for Acceptable difference – The Great Jan 1 '20 at 20:54
• Yes, currently I see differences of more than 10k, So I would like to know whether it is even a valid value or not? Hence I was looking for acceptable ranges of fluid balance – The Great Jan 2 '20 at 2:50
• Do I understand correctly that your measurement units are milliliters? So you're seeing differences of more than 10 liters in a single day from real patient data? – Carey Gregory Jan 2 '20 at 5:06
• Yes. It is in ml. you are right – The Great Jan 2 '20 at 5:09

In the Intensive Care Unit (ICU), water gain and loss in 24 h can be measured from:

• Water gain: drinking, tube feeding or intravenous infusion
• Water loss: urine

There can be substantial additional loses via excessive sweating, vomiting and diarrhea, and those are not usually measured, but only estimated and may or may not be recorded.

If the question is, what can be a possible difference between total water gain and loss in 24 hours, I'd say roughly 10 liters in each direction, but this is just what is physiologically possible and not likely what they would allow to occur in the ICU, where +2 to -2 liters would be more realistic.

If we are talking about absolute amounts of water gain and loss in 24 hours, they could be both up to about 30 liters.

Example 1: Treatment of severe dehydration. A patient who loses 30 liters of water per day by diarrhea due to cholera, would be treated by 30+ liters of fluid in that day.

Example 2: Excessive urine loss (polyuria). A person gets 5 liters of fluid in a day, but due to excessive urination caused by diabetes mellitus, he loses 10 liters of fluid. Again, in the ICU they would not likely allow that such great negative water balance would develop.

Example 3: Water intoxication. Water intoxication can happen, for example, when dehydration is treated by excessive amounts of water, let's say, by 5 liters in 2-3 hours - such mistakes should be rare in the ICU, but occasionally occur in everyday life... In one case, a 22-years-old man drank 6 liters of water in 2-3 hours and developed severe hyponatremia. It's probably not survivable to drink 10 liters of water in 2-3 hours for a person who is already well hydrated at the beginning of drinking.

Example 4: Hyperhydration with edema. In kidney or liver patients with impaired water balance regulation, water can accumulate in the body (which otherwise doesn't in significant amounts), which can result in generalized edema with 10+ liters of excessive fluid in the body, or in case of ascites (accumulation of fluid in the abdominal cavity), up to about 30 liters, as mentioned in this article. Anyway, such big amounts of water do not likely accumulate within 24 hours.

• Thanks for the response. Upvoted.. Can someone acquire infections when in ICU or die in ICU because of fluid overload? Fluid overload may not the direct cause of death but is it possible that fluid overload leads to some disease and the patient passes away. If someone is approaching death, how much would their fluid balance be? – The Great Jan 3 '20 at 13:05
• Yes, fluid overload is possible and is called water intoxication - the official cause would be "dilutional hyponatremia" and can be a direct cause of death. If you want I can say few things about that in the answer. – Jan Jan 3 '20 at 13:07
• Yes please. And what would be there range for people suffering from fluid overload? Very much appreciate your time and inputs – The Great Jan 3 '20 at 13:10
• Thank you for the help – The Great Jan 3 '20 at 13:24
• I realized, you asked about possible absolute amounts of water gain and loss (not only the differences between the two), so I added the info, that in cholera with severe diarrhea, it can be 30 liters of water loss treated by 30 liters of fluid. Then again, in the context of your question (already being treated in the ICU for 4 or more days), such high values are still more likely due to an error. – Jan Jan 4 '20 at 11:51