Delirium

Delirium is a clinical diagnosis. The core diagnostic phenotype is a disturbance in attention and awareness developing over hours to days, representing a change from baseline, fluctuating during the day, and accompanied by an additional cognitive disturbance. The syndrome cannot be better explained solely by a pre-existing neurocognitive disorder and should not be diagnosed in coma or markedly reduced arousal. PubMed+2PubMedDelirium in Older Persons: Advances in Diagnosis and Treatment - PMCPubMedDelirium diagnosis, screening and managementPubMedICU Delirium - StatPearls - NCBI Bookshelf

Obtain collateral history from family, caregivers, outpatient records, nursing staff, and the prior clinical team. In older adults, pre-existing dementia complicates assessment but does not exclude delirium; the clinically decisive feature is an acute change from the patient's usual cognition, attention, arousal, or behavior. Lewy body dementia may itself fluctuate and therefore requires especially careful baseline characterization. PubMed+1PubMedDifferentiating Delirium Versus Dementia in Older Adults - StatPearls - NCBI BookshelfPubMedDelirium in Older Persons: Advances in Diagnosis and Treatment - PMC

Hypoactive presentations are easily missed. New drowsiness, reduced interaction, diminished ability to follow conversation, or failure to sustain attention warrants the same evaluation as agitation. In ICU populations, delirium is a common manifestation of acute brain dysfunction and may affect up to 83% of mechanically ventilated patients. PubMed+1PubMedDelirium in Older Persons: Advances in Diagnosis and Treatment - PMCPubMedICU Delirium - StatPearls - NCBI Bookshelf

DSM-5 and ICD criteria are reference standards, but routine identification depends on repeated bedside observation and brief cognitive assessment. The CAM is widely used and has four features: acute onset with fluctuating course, inattention, disorganized thinking, and altered level of consciousness. A CAM-positive result requires the first two features plus either disorganized thinking or altered consciousness. PubMed+3PubMedDelirium in Older Persons: Advances in Diagnosis and Treatment - PMCPubMedApproach to Altered Mental Status and Inpatient DeliriumPubMedDiagnostic accuracy of the 4AT - The 4 ‘A’s test for detecting delirium in acute medical patients: a diagnostic accuracy study - NCBI BookshelfPubMedDelirium diagnosis, screening and management

The 4AT is a brief assessment designed for general clinical settings and includes alertness, orientation using the Abbreviated Mental Test-4, attention using months backward, and acute change or fluctuation. It can be performed in less than 2 minutes and does not require specialized training. PubMed+1PubMedDifferentiating Delirium Versus Dementia in Older Adults - StatPearls - NCBI BookshelfPubMedApproach to Altered Mental Status and Inpatient Delirium

In ICU patients, CAM-ICU and the Intensive Care Delirium Screening Checklist are extensively validated and can be used when patients cannot speak because of endotracheal intubation. Screening should inform a clinical assessment and precipitant search; it is not a substitute for etiologic evaluation. PubMedPubMedICU Delirium - StatPearls - NCBI Bookshelf

The mental-status examination may establish delirium, but the subsequent task is to identify its cause or causes. A thorough evaluation for reversible contributors is warranted even when no single etiology is immediately apparent. If the presumed precipitant is removed and delirium does not improve, expand or revisit the evaluation. PubMed+1PubMedApproach to Altered Mental Status and Inpatient DeliriumPubMedICU Delirium - StatPearls - NCBI Bookshelf

Focus testing on findings from the history and examination rather than ordering a uniform laboratory or imaging panel. The assessment should account for medication exposure, pain, oxygenation, hydration and nutrition, infection or other systemic illness, metabolic disturbance, bowel and bladder problems, sensory impairment, sleep deprivation, immobility, and recent surgery or critical illness. NEJM+2NEJMA Multicomponent Intervention to Prevent Delirium in ...PubMedApproach to Altered Mental Status and Inpatient DeliriumPubMedNon-pharmacological interventions for preventing delirium ...

Perform a focused neurologic examination and maintain a differential diagnosis for other causes of altered mental status. Delirium is a diagnosis of exclusion in ICU-focused references, and new confusion should not be presumed benign or attributed solely to chronic neurocognitive disease. PubMed+1PubMedApproach to Altered Mental Status and Inpatient DeliriumPubMedICU Delirium - StatPearls - NCBI Bookshelf

Multicomponent prevention addresses modifiable vulnerabilities and hospital exposures. In a seminal intervention study, cognitive impairment, sleep deprivation, immobility, visual impairment, hearing impairment, and dehydration were identified as delirium risk factors targeted by the intervention. NEJMNEJMA Multicomponent Intervention to Prevent Delirium in ...

A systematic review found that attention to nutrition and hydration, oxygenation, medication review, mood assessment, and bowel and bladder care was probably associated with prevention benefit. These measures are operationally useful because they also identify potentially reversible drivers in patients with established delirium. PubMedPubMedNon-pharmacological interventions for preventing delirium ...

For high-risk surgical patients, the American College of Surgeons identifies age, alcohol use, poor cognitive or physical function, and abnormal laboratory findings as risk factors, and states that targeted interventions may prevent or lessen postoperative delirium. facsfacsStrong for Surgery | ACS

Delirium is associated with longer hospital stay, lower six-month survival in ICU-focused evidence, and long-term cognitive impairment among critical illness survivors. PubMedPubMedICU Delirium - StatPearls - NCBI Bookshelf In older adults, delirium has also been associated with postdischarge mortality, institutionalization, and dementia independent of important confounders in a meta-analysis. NatureNatureDelirium | Nature Reviews Disease Primers

Postoperative delirium is associated with subsequent adverse cognitive trajectories, and delirium is linked to functional decline, readmissions, institutionalization, cognitive decline, dementia, and mortality in broader clinical literature summaries. NEJM+1NEJMCognitive Trajectories after Postoperative DeliriumchestnetAccurately representing the complications and impact of delirium - American College of Chest Physicians These associations do not establish that every outcome is directly caused by delirium, but they justify explicit discharge communication and follow-up planning.

At discharge, document the delirium episode, suspected or confirmed precipitants, baseline cognitive uncertainty, residual cognitive or functional deficits, and needed supervision or support. For patients with persistent symptoms or incomplete recovery, arrange reassessment rather than assuming return to baseline. PubMed+2PubMedApproach to Altered Mental Status and Inpatient DeliriumPubMedICU Delirium - StatPearls - NCBI BookshelfchestnetAccurately representing the complications and impact of delirium - American College of Chest Physicians