The first minutes of assessment are about the causes that kill or maim quickly: low glucose, sepsis, hypoxia, intracranial bleeding, meningitis, toxic states and withdrawal. A glucose, a full set of observations and a short neurological examination screen for most of them, which is why they come before any cognitive test. Confusion alone does not automatically mean 999: in suspected infection, an objective new altered mental state is a NICE high-risk sepsis feature and a collateral report of new altered behaviour is a moderate-to-high-risk feature, so apply the complete NICE criteria with clinical judgement [1]. NICE recommends NEWS2 in specified acute settings and advises considering an early warning score in community settings; in primary care, use full observations, the NICE community sepsis criteria and clinical judgement rather than a single NEWS2 threshold [1]. Subdural haematoma is the classic trap: the fall may have been days ago and unwitnessed, and the only sign may be fluctuating drowsiness in someone on an anticoagulant.

Onset and fluctuation are the two features that separate delirium from dementia, and both come from the history rather than a test score. That is why the 4AT gives 4 points to the acute-change item and why the collateral account matters so much: without it the test cannot be scored properly. A patient too drowsy or agitated to be tested still scores 4 or more, so the most unwell are not falsely reassured. Hypoactive delirium is under-recognised because the patient causes no trouble; a carer who says "she's just not herself, sleeping all day" is describing it. Record the 4AT score so that the trajectory can be tracked at review.

PINCH ME is not a guideline tool, but it matches the precipitants NICE asks clinicians to look for [4] and keeps the search systematic. A structured sweep stops the first abnormal result being accepted as the whole answer — bacteria in the urine or a low sodium may be one contributor among several. Total anticholinergic load, added up with an anticholinergic burden scale, is a modifiable contributor to both delirium and longer-term cognitive impairment: oxybutynin, tricyclics and sedating antihistamines all cross into the brain. Constipation and retention cause confusion through discomfort and are easily missed in people who cannot describe their symptoms.

Urinary retention and faecal impaction are easily missed causes, especially in older men and people taking opioids or anticholinergics, and are found only by examining the abdomen; palpate the bladder or use a bladder scanner. Pneumonia in frail older people can present with confusion and a raised respiratory rate but little fever or cough. Asterixis and myoclonus shift the differential towards metabolic or toxic causes. Unexplained bruising should prompt thought about falls on anticoagulation and, where the story does not fit, about safeguarding. Checking the medicines physically in the home often reveals double-dosing from old and new boxes or a recently started sedative that is not on the repeat template.

Bedside glucose is mandatory in every confused patient because hypoglycaemia is both dangerous and instantly reversible. Blood tests find the silent causes — hyponatraemia, hypercalcaemia, AKI, hepatic dysfunction and hypothyroidism rarely announce themselves on examination. Bacteriuria without infection is common in older people, so a positive dipstick in a confused patient often leads to an unnecessary antibiotic while the true cause is missed; send culture selectively [5]. CT head has a low yield when there is a clear medical cause and no focal signs, head injury, anticoagulation or reduced consciousness. An ECG provides the baseline QTc needed before haloperidol, because both the drug and the electrolyte disturbances of delirium can prolong it. Hypercalcaemia may be the first sign of myeloma or metastatic cancer, which is why it maps to NG12.

Community management of delirium is appropriate only when the cause is identified and treatable at home, the person is safe, and someone can supervise and monitor; any uncertainty favours admission. Carer strain often precipitates a crisis, so asking the carer how they are coping is part of managing the patient. Capacity is decision-specific; confusion alone does not mean a person lacks capacity, and GPs are often best placed to assess it and to record best-interests decisions made with the family.

Haloperidol does not treat delirium; it only reduces dangerous distress while the cause is treated, which is why NICE limits it to short-term use when de-escalation has failed [4]. Antipsychotics can cause severe sensitivity reactions in Lewy body disease, and haloperidol is contraindicated in Parkinson's disease and dementia with Lewy bodies [8], so knowing the dementia subtype before prescribing is essential. Alternative antipsychotics are not offered as standalone GP choices: when haloperidol is contraindicated, seek specialist input or follow a local protocol. Acetylcholinesterase inhibitors are not an acute treatment for delirium; dementia diagnosis and treatment belong to the memory-service pathway once delirium has resolved.

Non-drug measures are safe and target the same factors that precipitate and prolong delirium — sensory impairment, sleep disruption, immobility, dehydration and unfamiliar surroundings. They apply to every patient, whether or not medication is also needed, and carers can deliver most of them at home or in a care home. Explaining delirium to carers as the brain's reaction to illness reduces their distress and helps them recognise deterioration.

Delirium is associated with higher mortality, later institutionalisation and new dementia, so follow-up does not end when the acute episode settles. Cognitive tests during delirium are unreliable, so the dementia question is answered only after recovery [9]. A named stop date stops a short-term antipsychotic drifting onto the repeat list. For the SCA, the examiner will be listening for explicit, plain-language safety-netting for the carer, a named review plan, and an acknowledgement of carer strain.