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LearnPaediatric CalculationsLesson overview

Lesson overview

Paediatric Maintenance Fluids

Learn how to calculate hourly and daily paediatric maintenance-fluid estimates, then separate the arithmetic from fluid composition, clinical restriction, route, monitoring and guideline-specific limits.

About 30 minutesPaediatric CalculationsNo account required

Ready when you are

Start with short teaching slides, then answer the lesson questions. Your progress is saved in this browser.

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Learning outcomes

What you will learn

  • explain what a maintenance-fluid formula result represents in this maths lesson
  • split a weight into the first 10 kg, next 10 kg and kilograms above 20
  • calculate the 4-2-1 hourly estimate one band at a time
  • calculate the 100-50-20 daily estimate one band at a time
  • recognise which bands are used at 10 kg, 20 kg and weights above 20 kg
  • keep the hourly and daily methods separate instead of forcing them to match, while recognising that they can occasionally coincide at a particular weight
  • recognise that the arithmetic result does not by itself choose a real clinical fluid plan
  • separate maintenance volume from IV-fluid composition and understand the modern isotonic-maintenance boundary in the population covered by current guidance
  • recognise that reduced maintenance and large-child maximums are guideline-specific clinical adjustments rather than extra MedMaths formulas
  • use the current authorised kilogram weight basis without letting a unit conversion silently choose the clinical weight method
  • recognise that the formula does not decide whether IV therapy is needed and that oral or enteral hydration may be preferred when clinically appropriate
  • account for reassessment, total fluid exposure and fluid creep while keeping display precision separate from prescribing or pump precision

Clinical connection

Why this matters

A common arithmetic mistake is applying one band's rate to the whole weight. A separate clinical mistake is treating a mathematically correct full-maintenance estimate as the whole fluid prescription. This lesson teaches both boundaries explicitly.

Lesson plan

How the lesson works

  1. 1

    Learn

    Short teaching slides explain one idea at a time with plain-language examples.

  2. 2

    Practise

    Answer calculation or scenario questions and receive immediate feedback.

  3. 3

    Finish

    Complete the lesson mastery check and save your progress on this browser.

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