Delirium is a serious neuropsychiatric syndrome frequently experienced by palliative care inpatients. This syndrome is under-recognized by clinicians. While screening increases recognition, it is not a routine practice. This systematic review aims to examine methods, quality, and results of delirium prevalence and incidence studies in palliative care inpatient populations and discuss implications for delirium screening. A systematic search of the literature identified prospective studies reporting on delirium prevalence and/or incidence in inpatient palliative care adult populations from 1980 to 2012. Papers not in English or those reporting the occurrence of symptoms not specifically identified as delirium were excluded. Of the eight included studies, the majority (98.9%) involved participants (1079) with advanced cancer. Eight different screening and assessment tools were used. Delirium incidence ranged from 3% to 45%, while delirium prevalence varied, with a range of: 13.3%–42.3% at admission, 26%–62% during admission, and increasing to 58.8%–88% in the weeks or hours preceding death. Studies that used the Diagnostic and Statistical Manual–Fourth Edition reported higher prevalence (42%–88%) and incidence (40.2%–45%), while incidence rates were higher in studies that screened participants at least daily (32.8%–45%). Hypoactive delirium was the most prevalent delirium subtype (68%–86% of cases). The prevalence and incidence of delirium in palliative care inpatient settings supports the need for screening. However, there is limited consensus on assessment measures or knowledge of implications of delirium screening for inpatients and families. Further research is required to develop standardized methods of delirium screening, assessment, and management that are acceptable to inpatients and families.

Delirium is a common and distressing neurocognitive condition that frequently affects patients in palliative care settings and is often underdiagnosed. Expanding on a 2013 review, this systematic review examines the incidence and prevalence of delirium across all palliative care settings. This systematic review and meta-analyses were prospectively registered with PROSPERO and included a risk of bias assessment. Five electronic databases were examined for primary research studies published between 1980 and 2018. Studies on adult, non-intensive care and non-postoperative populations, either receiving or eligible to receive palliative care, underwent dual reviewer screening and data extraction. Studies using standardized delirium diagnostic criteria or valid assessment tools were included. Following initial screening of 2596 records, and full-text screening of 153 papers, 42 studies were included. Patient populations diagnosed with predominantly cancer (n = 34) and mixed diagnoses (n = 8) were represented. Delirium point prevalence estimates were 4%–12% in the community, 9%–57% across hospital palliative care consultative services, and 6%–74% in inpatient palliative care units. The prevalence of delirium prior to death across all palliative care settings (n = 8) was 42%–88%. Pooled point prevalence on admission to inpatient palliative care units was 35% (confidence interval = 0.29–0.40, n = 14). Only one study had an overall low risk of bias. Varying delirium screening and diagnostic practices were used. Delirium is prevalent across all palliative care settings, with one-third of patients delirious at the time of admission to inpatient palliative care. Study heterogeneity limits meta-analyses and highlights the future need for rigorous studies.

Better understanding of patient and family member experiences of delirium and related distress during critical care is required to inform the development of targeted nonpharmacologic interventions. To examine and synthesize qualitative data on patient and family member delirium experiences and relieving factors in the Intensive Care Unit (ICU). We conducted a systematic review and qualitative meta-synthesis. Eligible studies contained adult patient or family quotes about delirium during critical care, published in English in a peer-reviewed journal since 1980. Data sources included PubMed, Embase, CINAHL, PsycINFO, Web of Science, Cochrane and Clinicaltrials.gov. Systematic searches yielded 3238 identified articles, of which 14 reporting 13 studies were included. Two reviewers independently extracted data into a Microsoft Excel spreadsheet. Qualitative meta-synthesis was performed through line-by-line coding of relevant quotes, organization of codes into descriptive themes, and development of analytical themes. Five patients/family members with experience of ICU delirium contributed to the thematic analysis. Qualitative meta-synthesis resulted in four major themes and two sub-themes. Key new patient and family-centric insights regarding delirium-related distress in the ICU included articulation of the distinct emotions experienced during and after delirium (for patients, predominantly fear, anger and shame); its 'whole-person' nature; and the value that patients and family members placed on clinicians' compassion, communication, and connectedness. Distinct difficult emotions and other forms of distress are experienced by patients and families during ICU delirium, during which patients and families highly value human kindness and empathy. Future studies should further explore and address the many facets of delirium-related distress during critical care using these insights and include patient-reported measures of the predominant difficult emotions.