Nurses’ usage of validated tools to assess for delirium in general acute care settings: A scoping review protocol

Introduction

Delirium is an acute syndrome, characterised by altered levels of cognition, awareness, and attention (Diagnostic and statistical manual of mental disorders: DSM-5. Fifth edition, 2013). It is a major concern for public health as it is associated with a number of adverse effects, including a twofold increased risk of mortality, and a variety of cognitive and functional impairments. These include an increased risk of dementia, memory and concentration problems, sleep disturbances, institutionalisation, and need for long-term care (Bickel et al., 2008; Davis et al., 2012; Koster et al., 2009; Witlox et al., 2010). Additionally, there are negative impacts on the hospital macroeconomics, as delirium is associated with longer hospital stays, an increased chance of readmission and increased financial costs (Kinchin et al., 2021; Lim et al., 2023). There is no one defined pathophysiology for delirium, however it is hypothesised that there are numerous pathological factors that interact with each other and it is the specific types of interactions that result in the various presentations of delirium (Maldonado, 2018). There are, however, a number of well-established risk factors for delirium that have been identified within the literature. Increased age, dementia, and comorbid physical illnesses are known predisposing risk factors for delirium (Lim et al., 2023; MacLullich & Shenkin, 2019; Tieges et al., 2021). There are also a number of precipitating risk factors; urinary catheterisation, polypharmacy, and surgery (MacLullich & Shenkin, 2019; Tieges et al., 2021). These factors often can occur in general acute hospital settings. Additionally, hospitalisation itself and prolonged hospital stays are associated with the development of delirium (MacLullich & Shenkin, 2019).

Prevalence rates of delirium vary greatly within the literature depending on the population of the study. However, the estimated occurrence rate in hospitalised adults is 10–30% (Bellelli et al., 2014; Tieges et al., 2021; Titlestad et al., 2024; Waszynski et al., 2024). A prospective cohort study found that 17.7% of patients aged 70 and over had delirium upon admission to the hospital and an additional 11.6% of patients aged 70 and over developed delirium during their stay at the hospital (Dolan et al., 2023). Early detection of delirium, both for patients who arrive at a general acute care setting and for those who develop it in a general acute care setting, is crucial. Patients with unrecognised delirium are at a much higher risk for mortality upon discharge than patients with recognised delirium (Lee et al., 2022) and early diagnosis is a vital step in the treatment of delirium and is necessary in order to achieve the best outcomes (Zoremba & Coburn, 2019). However, despite the high occurrence of delirium and the importance of swift diagnosis, it is estimated that 50–75% cases are missed in such general acute care settings (Pezzullo et al., 2019).

Delirium can be detected through the use of assessment tools or instruments. There are a variety of different assessment tools that have been designed that can screen for delirium in different environments and for different purposes. Many of these aim to be rapid and require little training, with the goal of being used multiple times a day (Liu et al., 2023). Guidelines regarding what validated assessment tools to use will vary by country and care setting. Wales and England follow NICE guidelines, a comprehensive set of guidelines that document general acute care setting protocol from the admission of a patient to the treatment of delirium. They support the 4AT assessment, unless a patient is in critical care or the recovery room when the CAM-ICU is recommended (National Institute for Health and Clinical Excellence, 2023). However, the existence of guidelines does not necessarily equate to consistent assessments. Ankravs et al. (2020) found that while the majority of general acute care settings in Australia and New Zealand have documented protocols, policies, or guidelines regarding the daily assessment for delirium, only just over half of patients received a delirium assessment. Nurses are a key component to delirium diagnosis in general acute care settings. As they provide around-the-clock care for the patient they are in a position to identify any fluctuations that indicate the need for a validated delirium assessment (Brooke & Manneh, 2018). Additionally, many validated delirium assessment tools are designed to be administered by nurses (Grover & Kate, 2012), or designed not to require specialised training (Bellelli et al., 2014). However, as previously stated, delirium cases are frequently missed in general acute care settings which can have extremely negative outcomes for the patient. One explanation for this could be the underutilisation of validated delirium assessment tools in hospital wards. Azizi et al. (2024) found that almost 60% of Irish wards used personal judgement as the method of assessment for delirium. The 4AT, an assessment tool that is recommended for use in Irish and British general acute care settings, has a sensitivity of 89.7% and specificity 84.1% (Bellelli et al., 2014). Validated assessment tools are far more reliable than personal judgement when assessing delirium, and this was demonstrated in Azizi et al. (2024) study as patients that were assessed with validated tools had a higher chance of being diagnosed with delirium than patients that were assessed with personal judgment. An increase in the usage of validated assessment tools has the potential to reduce the number of missed delirium cases seen in hospitals.

Despite delirium being recognised as a neurological condition for millennia, research on the topic is still relatively novel (Slooter, 2017). Therefore, there is limited work done on understanding the utilisation of validated delirium assessment tools. Much of the literature that exists focuses exclusively on intensive care units, postoperative delirium, or other specific contexts. There has been little done to have a broad overview of the phenomenon and that is what this scoping review aims to address. This review will build on what is already known about nurses' use of validated assessment tools and attempt to ascertain what is being done, what is not being done, and the reasons behind both.

Review question

This scoping review will identify how validated assessment tools are used by nurses in general acute care settings to assess for delirium, and the barriers and enablers for said tools’ use.

The questions that will contribute to the stated aim are:

Methods

A scoping review was considered to be most suitable for this research for a variety of reasons. Firstly, the aim of this research is to map the existing knowledge base. Secondly, the area of interest is novel. Finally, the research question includes a broad population, concept, and context. Therefore, a scoping review is most appropriate. (Arksey & O’Malley, 2005). This scoping review will be conducted in accordance with the Joanna Briggs Institute (JBI) methodology for scoping reviews (Peters et al., 2020). The Preferred Reporting Items for Systematic reviews Meta-Analysis extension for Scoping Reviews (PRISMA-ScR) will be used to guide the reporting of this review (Tricco et al., 2018). This review will follow the nine stages of conducting a scoping review as outlined by the JBI methodology. The first three stages have been complete; determine the objectives and questions of the research; create an inclusion criteria; and develop a strategy for the searching, selection, extraction, and presentation of the evidence. Stages four to eight will involve the evidence search, selection, extraction, analysis, and presentation. Finally, stage nine will summarise the evidence in the context of the research question, draw conclusions, and address any implications of the findings. (Peters et al., 2020). A preliminary search of CINAHL, PubMed (MEDLINE), Scopus, and Web of Science was conducted and there are no existing scoping reviews on the topic. This scoping review protocol was registered on the 15th of January 2025 on Open Science Framework. Registration DOI: https://doi.org/10.17605/OSF.IO/6QEGB

Discussion

This protocol outlines the structure of a scoping review that will identify how validated assessment tools are used by nurses in general acute care settings to assess for delirium, and the barriers and enablers for said tools’ use. The scoping review will do so by investigating what validated assessment tools are most commonly used to assess for delirium, if there is any evidence of widespread usage of said tools, and what prevents or enables nurses’ using the tools. Should the scoping review differ from this protocol in any way, the ways in which and the reasons for will be acknowledged in the scoping review. The scoping review also aims to identify research gaps that can guide future researchers in the area of delirium.

Ethics and consent

Ethical approval and consent are not required.