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Maintenance fluids (NG29)
What a person who cannot drink needs in 24 hours, from NICE NG29. Maintenance only — it does not replace losses and it is not resuscitation, and giving maintenance to someone who is volume-depleted is a common way to under-resuscitate slowly.
Before you use it
Use IDEAL body weight in obesity and consider capping the total at about 2.5 litres a day — 30 ml/kg of an actual weight of 140 kg is not a maintenance prescription, it is an overload. Prescribe against today's U&E, not yesterday's: the potassium figure below is a starting requirement and is wrong the moment the potassium is abnormal. Reassess daily and write a stop date.
Source: NICE CG174 / NG29 — IV fluid therapy in adults in hospital
Checked, and shown
Every threshold on this page was checked against its primary source by a practising doctor. Here is what that involved, and what it found.