An older patient becomes newly confused, with a dry mouth and dark urine. What should the nurse suspect and do?

Suspect dehydration, assess fluid status and escalate as needed

Record confusion only, with no fluid assessment

A patient's fluid chart shows much greater output than input over 24 hours. What does this suggest?

A negative fluid balance that needs review

That the patient is overloaded with fluid

Which patient is at highest risk of dehydration on a ward?

A frail older person who cannot reach or hold a drink unaided

A young independent adult with free access to water

A patient who is fully mobile and drinking well

A patient about to be discharged home well

A patient is not drinking enough. What is an appropriate first nursing action?

Offer drinks regularly, within reach, and record intake

Wait for a doctor to prescribe intravenous fluids first

Assume they will drink when thirsty

Remove the fluid chart to reduce paperwork

Part B3 of 8 Assessing Needs and Planning Care Chapter 37 of 75

Hydration and Dehydration Assessment Questions

NMC CBT hydration practice: signs of dehydration, fluid balance charts, at-risk patients, and worked scenario answers.

Start reading ← All 75 chapters ~5 min read

By JobLabs Editorial · UK healthcare reference editorial team

· July 16, 2026 · Updated Jul 17, 2026 · 2 min read

Hydration is basic care that gets missed under pressure, and the consequences fall hardest on the people least able to speak up. The CBT tests whether you can recognise dehydration, keep an accurate fluid balance chart, and know who is most at risk.

Recognising dehydration

The signs are worth knowing as a cluster: thirst, a dry mouth, reduced skin turgor, dark or reduced urine, a fast pulse, and low blood pressure. In older people, new confusion is often the first sign, before the more obvious ones, which is why a suddenly confused older patient should prompt a check of their fluid status rather than a shrug about ageing. Reduced or dark urine is one of the earliest and easiest signs to monitor, which is why urine output is tracked so closely.

The fluid balance chart

A fluid balance chart records everything in and everything out. Input covers oral drinks, intravenous fluids and feeds. Output covers urine, vomit, drains and stoma losses. The two sides are totalled, usually over 24 hours, to show whether the patient is in positive or negative balance. Questions here often check that you record each item on the correct side, and that you can read the pattern: output well above input is a negative balance that needs review.

An accurate chart is only accurate if it is actually filled in, in real time. A chart with gaps tells you nothing.

Who is at risk

Certain patients are far more likely to become dehydrated: older people, young children, and anyone who cannot drink independently or does not reliably feel thirst. A frail patient who cannot reach or hold a cup depends entirely on staff. Add vomiting, diarrhoea, fever or poorly controlled diabetes and losses rise further.

Act early

The nursing response is often simple and effective: offer drinks regularly, keep them within reach, help the person who needs it, and record what they take. You do not wait passively for intravenous fluids to be prescribed, or assume someone will drink when thirsty, when they may not feel thirst at all. Next: falls risk assessment. Five hydration scenarios first.

Sources & further reading

Key takeaway from Hydration and Dehydration Assessment Questions

Frequently asked questions

What goes on a fluid balance chart?

Everything in and everything out. Input includes oral drinks, intravenous fluids and feeds; output includes urine, vomit, drains and stoma losses. Totalled accurately over 24 hours, it shows whether a patient is in positive or negative balance.

Who is most at risk of dehydration?

Older people, young children, and anyone who cannot drink independently or does not feel thirst reliably. People with vomiting, diarrhoea, fever or poorly controlled diabetes lose fluid faster. In older people, confusion may be the first sign.

Why is reduced urine output important?

Dark, concentrated or reduced urine is an early sign the body is conserving water. A falling output can also signal that the kidneys are affected. It is one of the clearest and easiest signs to monitor, which is why urine is recorded on the balance chart.

Check your understanding

Quick quiz: Hydration and Dehydration Assessment Questions

5questions. Click an answer to see the explanation. Your score is saved on this device only.

1
An older patient becomes newly confused, with a dry mouth and dark urine. What should the nurse suspect and do?
New confusion with a dry mouth and dark urine points to dehydration, and confusion is often the first sign in older people. You assess fluid status, encourage or provide fluids, and escalate if needed. Dismissing it as ageing, or restricting fluids, would worsen the problem.
2
Which of these belongs in the output section of a fluid balance chart?
Output is fluid leaving the body: urine, vomit, drain and stoma losses. Oral drinks, IV fluids and feeds are all inputs. Mixing these up makes the chart meaningless, so recording each on the correct side matters.
3
A patient's fluid chart shows much greater output than input over 24 hours. What does this suggest?
Output well above input is a negative balance, suggesting the patient may be losing more fluid than they are taking in, which can lead to dehydration. It needs review and action, not dismissal. Overload would show the opposite pattern.
4
Which patient is at highest risk of dehydration on a ward?
A frail older person who cannot drink independently depends entirely on staff for fluids and may not feel or express thirst, making them high risk. Independent, mobile, well-hydrated patients are far less likely to become dehydrated without noticing.
5
A patient is not drinking enough. What is an appropriate first nursing action?
Encouraging and offering drinks, keeping them within reach, helping if needed, and recording intake is basic, effective nursing. You do not wait passively for IV fluids or assume thirst will prompt drinking, especially in someone who may not feel it.