The bedside tool
Using ACE-T
You have just done a 4AT, or another delirium screen, and the result is positive. Or you are worried that a patient has delirium. Start ACE-T now, and work through the three domains in parallel.
Four hours, and urgent concerns first
Aim to complete, start or escalate the actions that apply within four hours of the positive screen. Act on urgent concerns immediately, using your local escalation pathway.
Four hours is a practical target for the whole initial response. Several actions can happen at the same time.
Within your role, with the team
ACE-T covers the nursing part of the first response. Diagnosis, investigations and prescribing stay with the team members whose role covers them, under local policy.
Use your judgement: some prompts will not apply to every patient, and others may need adding.
Acute Triggers
What might be causing or worsening the delirium?
Check observations
Pulse, blood pressure, oxygen saturation, respiratory rate, temperature and conscious level.
Why: Abnormal observations can point to acute illness, such as infection, low oxygen levels or dehydration, that may be causing or worsening the delirium.Check capillary blood glucose
Why: Low or high blood glucose can cause delirium, and it is quick to check at the bedside.Check that routine blood tests have been sent
Why: Blood tests help the team look for causes such as infection, dehydration and electrolyte problems. Follow local policy on who requests and reviews them.Assess for urinary retention and constipation
Why: Both are common, uncomfortable and easily missed, and both can contribute to delirium.Assess hydration status
Why: Dehydration is a common contributor to delirium and can often be corrected.Assess nutrition status
Why: Poor nutrition is a recognised risk factor for delirium, and people with delirium often need help to eat and drink.Start or review an infection work-up, as appropriate
For example, urinalysis or a wound check.
Why: Infection is a common trigger. Be guided by symptoms and signs, and by local guidance on which tests to use.Assess pain
Record it as none, mild, moderate or severe.
Why: Pain can cause or worsen delirium, and people with delirium may not report it. Look for non-verbal signs, particularly if the person has communication difficulties.Check whether a medication review has been completed
Why: Medicines are a common contributor, including new sedating drugs and regular medicines that have been missed or stopped. Raise any concerns with the prescriber.
Patient Experience
How is the person feeling, and what would help?
Check for distress
Use the Quick Distress Assessment Tool (QDAT) where appropriate.
Why: Distress is common in delirium, and a quiet or drowsy person may still be distressed.Note any agitation
Why: Describe what you see and when it happens. Agitation can reflect pain, fear or another need that the team can address.Provide reassurance and reorientation
Explain who you are, where the person is and what is happening.
Why: Calm, clear explanation helps people make sense of their surroundings. Repeat it as often as needed.Consider the patient’s environment
For example, whether a single room is needed.
Why: Noise, poor lighting and moves between wards or rooms can add to confusion.Make sure glasses, hearing aids and other communication aids are available
Why: People are less disorientated when they can see and hear clearly. Check that aids work and are within reach.Consider involving relatives, friends or carers
Why: People who know the patient can describe their usual self, offer familiar reassurance and help the team notice change.
Optional score
Quick Distress Assessment Tool (QDAT)
Observe the person, then ask:
“How are you feeling? Is anything bothering you?”
Appears settled, lying or sitting comfortably, with no signs of pain or distress.
Verbalises mild distress and/or appears mildly concerned or worried (for example, furrowed brow).
Verbalises moderate distress and/or displays physical signs of distress (for example, restlessness).
Verbalises severe distress and/or is visibly in distress throughout the assessment, needing ongoing reassurance.
Quick Distress Assessment Tool (QDAT), as described in the ACE-T manuscript; see McCartney H et al. Age Ageing 2025;54(6):afaf166.
Treatment: Nursing treatment and communication
What does the person need now, and who needs to know?
Consider falls risk
Why: Delirium increases the risk of falls. Review the person’s risk and use local falls prevention measures.Consider whether fluids, oxygen or other immediate supportive measures are needed
Why: Some people need these straight away. They are not automatic for everyone with delirium: decide within your scope of practice and local policy.Document “delirium” or “? delirium” and the 4AT score in the clinical record
If your service uses a different screening tool, record its score.
Why: Writing it down makes the delirium visible to everyone who reads the record, and gives a starting point for tracking change.Communicate the screening score and relevant findings to the clinical team
Why: The team needs this information to complete a clinical assessment and plan treatment.Inform the family, where appropriate
Why: Families are often worried by sudden change in someone they know well. They can also tell you what is new.Offer the delirium information leaflet to the patient and family, where appropriate
Why: Written information helps people understand delirium and remember what they were told.Discuss the treatment plan with the multidisciplinary team
Why: Agree who does what next. Delirium care continues beyond the first four hours.
After the first four hours
Keep the plan going
ACE-T is the start of delirium treatment. Revisit relevant prompts as the person’s condition changes, and follow the treatment plan agreed with the team.
Hand over clearly
At handover, include the delirium or suspected delirium, the screening score, what has been done, and anything still outstanding or escalated.
Adapted from Table 1 of the ACE-T development and pilot manuscript (Cours et al., submitted for publication 2026). The web version names the 4AT as the screening tool; ACE-T can be used after any locally used delirium screen. The “Why” lines are teaching notes for this website, consistent with NICE guideline CG103. Source and citation.