Exploring Antipsychotic Use for Delirium Management in Adults in Hospital, Sub-Acute Rehabilitation and Aged Care Settings: A Systematic Literature Review.

Background: International guidelines discourage antipsychotic use for delirium; however, concerns persist about their continued use in clinical practice.

Objectives: We aimed to describe the prevalence and patterns of antipsychotic use in delirium management with regard to best-practice recommendations. Primary outcomes investigated were prevalence of use, antipsychotic type, dosage and clinical indication.

Methods: Eligibility criteria: studies of any design that examined antipsychotic use to manage delirium in adults in critical care, acute care, palliative care, rehabilitation, and aged care were included. Studies of patients in acute psychiatric care, with psychiatric illness or pre-existing antipsychotic use were excluded.

Information sources: we searched five health databases on 16 August, 2023 (PubMed, CINAHL, Embase, APA PsycInfo, ProQuest Health and Medical Collection) using MeSH terms and relevant keywords, including 'delirium' and 'antipsychotic'. Risk of bias: as no included studies were randomised controlled trials, all studies were assessed for methodological quality using the Mixed Methods Appraisal Tool.

Synthesis of results: descriptive data were extracted in Covidence and synthesised in Microsoft Excel.

Results: Included studies: 39 studies published between March 2004 and August 2023 from 13 countries (n = 1,359,519 patients). Most study designs were retrospective medical record audits (n = 16).

Synthesis of results: in 18 studies, participants' mean age was ≥65 years (77.79, ±5.20). Palliative care had the highest average proportion of patients with delirium managed with antipsychotics (70.87%, ±33.81%); it was lower and varied little between intensive care unit (53.53%, ±19.73%) and non-intensive care unit settings [medical, surgical and any acute care wards] (56.93%, ±26.44%) and was lowest in in-patient rehabilitation (17.8%). Seventeen different antipsychotics were reported on. In patients aged ≥65 years, haloperidol was the most frequently used and at higher than recommended mean daily doses (2.75 mg, ±2.21 mg). Other antipsychotics commonly administered were olanzapine (mean 11 mg, ±8.54 mg), quetiapine (mean 64.23 mg, ±43.20 mg) and risperidone (mean 0.97 mg, ±0.64 mg).

Conclusions: The use of antipsychotics to manage delirium is strongly discouraged in international guidelines. Antipsychotic use in delirium care is a risk for adverse health outcomes and a longer duration of delirium, especially in older people. However, this study has provided evidence that clinicians continue to use antipsychotics for delirium management, the dose, frequency and duration of which are often outside evidence-based guideline recommendations. Clinicians continue to choose antipsychotics to manage delirium symptoms to settle agitation and maintain patient and staff safety, particularly in situations where workload pressures are high. Sustained efforts are needed at the individual, team and organisational levels to educate, train and support clinicians to prioritise non-pharmacological interventions early before deciding to use antipsychotics. This could prevent delirium and avert escalation in behavioural symptoms that often lead to antipsychotic use.