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LearnIV CalculationsLesson overview

Lesson overview

IV Volume, Time & Rate Basics

Learn the volume, time and rate relationship used in basic IV arithmetic.

About 18 minutesIV CalculationsNo account required

Ready when you are

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

Practise this lesson

Choose Foundation, Beginner, Intermediate or Advanced for this lesson topic.

Learning outcomes

What you will learn

  • explain IV and infusion in plain English
  • tell volume, time and rate apart
  • read mL/hr as millilitres per hour or millilitres each hour
  • calculate rate when volume and time are known
  • calculate time when volume and rate are known
  • calculate volume when rate and time are known
  • match minutes or hours to the time unit used in the rate
  • convert the fractional part of decimal hours back to clock minutes
  • recognise that the three equations describe one constant-rate interval
  • distinguish mL/hr pump arithmetic from gravity gtt/min calculations
  • stop when two connected values from the same interval are not available

Clinical connection

Why this matters

Volume, time and rate use different units and do different jobs. The simple equations also assume one constant-rate interval and a specified practice volume or verified volume to be infused. If you mix the jobs or combine values from different intervals, correct arithmetic can still answer the wrong question.

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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