Prevention of delirium (POD) for older people in hospital: study protocol for a randomised controlled feasibility trial

Delirium risk screening and assessment among older patients in general wards and the emergency department: a best practice implementation project

OBJECTIVES

The aim of this project was to improve compliance with evidence-based criteria regarding risk of delirium and the assessment of delirium among older patients in the general hospitalization wards and the emergency department.

INTRODUCTION

More than 50% of older hospitalized patients experience delirium. Some studies have highlighted the need to implement an orientation protocol in the emergency department and to continue this in the general wards, with the aim of decreasing the delirium rate among older patients admitted to hospital.

METHODS

The project followed the JBI evidence implementation framework. We conducted a baseline audit, a half-way audit, and final audit of 50 patients at risk of delirium admitted to the emergency department and the general wards, respectively. The audits measured compliance with eight criteria informed by the available evidence.

RESULTS

In the final audit, three of the eight criteria achieved more than 50% compliance in the general wards: pressure injury screening (96%); monitoring changes (74%); and performing interventions (76%). In the emergency department, worse results were reported because of the service conditions. The exception was the criterion on the training of nurses on the topic, with 98%. The integration of a tool to screen for delirium in older patients in the hospital's electronic clinical history records increased the percentage of compliance with audit criteria regarding the use of the scale and delirium detection (rising from 0% to 32% in the final audit in the general wards).

CONCLUSION

Through the implementation of this project, validated and evidence-based evaluation will ensure that nurses are supported through appropriate measures to reduce patient confusion and aggression resulting from delirium.

Clinical and Epidemiological Approach to Delirium in an Acute Care Unit: A Cross-Sectional Study

During hospital admissions, the union of various factors, those related to acute pathology, dependency conditions, cognitive impairment, change of habitual environment, and others, can cause delirium. Acute delirium in the elderly (ADE) occurs in around a third of patients over 70 years of age. The syndrome generates serious complications that increase hospital morbidity and mortality and a high cost for the health administration. This study aimed to determine the clinical and epidemiological profile of ADE in an internal medicine unit. A descriptive cross-sectional study was carried out using a convenience test. A total of 356 patients participated between September and November 2021. Sociodemographic variables, predisposing and precipitating factors of ADE, methods of action against ADE, and the impact on functional and cognitive deterioration were analyzed. A total of 35.1% of the patients developed ADE, mostly of the hyperactive type and of nocturnal appearance. ADE was mainly treated with psychoactive drugs and 22% required mechanical restraint, with non-pharmacological preventive strategies, support, and caregiver training being the main tools for controlling ADE during hospital admission.

Patient Profile and Management of Delirium in Older Adults Hospitalized Due to COVID-19

SARS-CoV-2 can cause neurologic symptoms, as well as respiratory ones. Older adults are at risk of developing acute delirium in older persons (ADOP). The combination of experiencing respiratory isolation due to COVID-19, as well as other associated risk factors for older adults, may have had an impact on ADOP and ADOP management in the acute hospital setting. This study aimed to analyze the characteristics of ADOP in patients admitted to a COVID-19 unit. An observational prospective study on a sample of 108 patients was carried out between November 2020 and May 2021. The following data were collected: sociodemographic characteristics, risk factors for ADOP, management of ADOP, and impact on ADOP on both functional and cognitive deterioration. A 29.6% proportion of older adults admitted to an acute COVID-19 unit presented hyperactive ADOP, mainly during the night. Management of ADOP in our sample involved mainly pharmacological treatment and had a serious impact on hospital stay and both functional and cognitive deterioration. Preventive strategies and being accompanied by a relative or a carer may be useful to manage ADOP during hospital admission due to COVID-19.

PERFECTED enhanced recovery pathway (PERFECT-ER) versus standard acute hospital care for people after hip fracture surgery who have cognitive impairment: a feasibility cluster randomised controlled trial

OBJECTIVES

Assess feasibility of a cluster randomised controlled trial (RCT) to measure clinical and cost-effectiveness of an enhanced recovery pathway for people with hip fracture and cognitive impairment (CI).

DESIGN

Feasibility trial undertaken between 2016 and 2018.

SETTING

Eleven acute hospitals from three UK regions.

PARTICIPANTS

284 participants (208 female:69 male).

INCLUSION CRITERIA

aged >60 years, confirmed proximal hip fracture requiring surgical fixation and CI; preoperative AMTS ≤8 in England or a 4AT score ≥1 in Scotland; minimum of 5 days on study ward; a 'suitable informant' able to provide proxy measures, recruited within 7 days of hip fracture surgery.

EXCLUSION CRITERIA

no hip surgery; not expected to survive beyond 4 weeks; already enrolled in a clinical trial.

INTERVENTION

PERFECT-ER, an enhanced recovery pathway with 15 quality targets supported by a checklist and manual, a service improvement lead a process lead and implemented using a plan-do-study-act model.

PRIMARY AND SECONDARY OUTCOME MEASURES

Feasibility outcomes: recruitment and attrition, intervention acceptability, completion of participant reported outcome measures, preliminary estimates of potential effectiveness using mortality, EQ-5D-5L, economic and clinical outcome scores.

RESULTS

282 participants were consented and recruited (132, intervention) from a target of 400. Mean recruitment rates were the same in intervention and control sites, (range: 1.2 and 2.7 participants/month). Retention was 230 (86%) at 1 month and 54%(144) at 6 months. At 3 months a relatively small effect (one quarter of an SD) was observed on health-related quality of life of the patient measured with EQ-5D-5L proxy in the intervention group.

CONCLUSION

This trial design was feasible with modifications to recruitment. Mechanisms for delivering consistency in the PERFECT-ER intervention and participant retention need to be addressed. However, an RCT may be a suboptimal research design to evaluate this intervention due to the complexity of caring for people with CI after hip fracture.

TRIAL REGISTRATION NUMBER

ISRCTN99336264.

Non-pharmacological interventions for preventing delirium in hospitalised non-ICU patients

BACKGROUND

Delirium is an acute neuropsychological disorder that is common in hospitalised patients. It can be distressing to patients and carers and it is associated with serious adverse outcomes. Treatment options for established delirium are limited and so prevention of delirium is desirable. Non-pharmacological interventions are thought to be important in delirium prevention.  OBJECTIVES: To assess the effectiveness of non-pharmacological interventions designed to prevent delirium in hospitalised patients outside intensive care units (ICU).

SEARCH METHODS

We searched ALOIS, the specialised register of the Cochrane Dementia and Cognitive Improvement Group, with additional searches conducted in MEDLINE, Embase, PsycINFO, CINAHL, LILACS, Web of Science Core Collection, ClinicalTrials.gov and the World Health Organization Portal/ICTRP to 16 September 2020. There were no language or date restrictions applied to the electronic searches, and no methodological filters were used to restrict the search.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of single and multicomponent non-pharmacological interventions for preventing delirium in hospitalised adults cared for outside intensive care or high dependency settings. We only included non-pharmacological interventions which were designed and implemented to prevent delirium.  DATA COLLECTION AND ANALYSIS: Two review authors independently examined titles and abstracts identified by the search for eligibility and extracted data from full-text articles. Any disagreements on eligibility and inclusion were resolved by consensus. We used standard Cochrane methodological procedures. The primary outcomes were: incidence of delirium; inpatient and later mortality; and new diagnosis of dementia. We included secondary and adverse outcomes as pre-specified in the review protocol. We used risk ratios (RRs) as measures of treatment effect for dichotomous outcomes and between-group mean differences for continuous outcomes. The certainty of the evidence was assessed using GRADE. A complementary exploratory analysis was undertaker using a Bayesian component network meta-analysis fixed-effect model to evaluate the comparative effectiveness of the individual components of multicomponent interventions and describe which components were most strongly associated with reducing the incidence of delirium.

MAIN RESULTS

We included 22 RCTs that recruited a total of 5718 adult participants. Fourteen trials compared a multicomponent delirium prevention intervention with usual care. Two trials compared liberal and restrictive blood transfusion thresholds. The remaining six trials each investigated a different non-pharmacological intervention. Incidence of delirium was reported in all studies.  Using the Cochrane risk of bias tool, we identified risks of bias in all included trials. All were at high risk of performance bias as participants and personnel were not blinded to the interventions. Nine trials were at high risk of detection bias due to lack of blinding of outcome assessors and three more were at unclear risk in this domain.  Pooled data showed that multi-component non-pharmacological interventions probably reduce the incidence of delirium compared to usual care (10.5% incidence in the intervention group, compared to 18.4% in the control group, risk ratio (RR) 0.57, 95% confidence interval (CI) 0.46 to 0.71, I2 = 39%; 14 studies; 3693 participants; moderate-certainty evidence, downgraded due to risk of bias).  There may be little or no effect of multicomponent interventions on inpatient mortality compared to usual care (5.2% in the intervention group, compared to 4.5% in the control group, RR 1.17, 95% CI 0.79 to 1.74, I2 = 15%; 10 studies; 2640 participants; low-certainty evidence downgraded due to inconsistency and imprecision).  No studies of multicomponent interventions reported data on new diagnoses of dementia.  Multicomponent interventions may result in a small reduction of around a day in the duration of a delirium episode (mean difference (MD) -0.93, 95% CI -2.01 to 0.14 days, I2 = 65%; 351 participants; low-certainty evidence downgraded due to risk of bias and imprecision). The evidence is very uncertain about the effect of multicomponent interventions on delirium severity (standardised mean difference (SMD) -0.49, 95% CI -1.13 to 0.14, I2=64%; 147 participants; very low-certainty evidence downgraded due to risk of bias and serious imprecision). Multicomponent interventions may result in a reduction in hospital length of stay compared to usual care (MD -1.30 days, 95% CI -2.56 to -0.04 days, I2=91%; 3351 participants; low-certainty evidence downgraded due to risk of bias and inconsistency), but little to no difference in new care home admission at the time of hospital discharge (RR 0.77, 95% CI 0.55 to 1.07; 536 participants; low-certainty evidence downgraded due to risk of bias and imprecision). Reporting of other adverse outcomes was limited.  Our exploratory component network meta-analysis found that re-orientation (including use of familiar objects), cognitive stimulation and sleep hygiene were associated with reduced risk of incident delirium. Attention to nutrition and hydration, oxygenation, medication review, assessment of mood and bowel and bladder care were probably associated with a reduction in incident delirium but estimates included the possibility of no benefit or harm.  Reducing sensory deprivation, identification of infection, mobilisation and pain control all had summary estimates that suggested potential increases in delirium incidence, but the uncertainty in the estimates was substantial.  Evidence from two trials suggests that use of a liberal transfusion threshold over a restrictive transfusion threshold probably results in little to no difference in incident delirium (RR 0.92, 95% CI 0.62 to 1.36; I2 = 9%; 294 participants; moderate-certainty evidence downgraded due to risk of bias).  Six other interventions were examined, but evidence for each was limited to single studies and we identified no evidence of delirium prevention.  AUTHORS' CONCLUSIONS: There is moderate-certainty evidence regarding the benefit of multicomponent non-pharmacological interventions for the prevention of delirium in hospitalised adults, estimated to reduce incidence by 43% compared to usual care. We found no evidence of an effect on mortality. There is emerging evidence that these interventions may reduce hospital length of stay, with a trend towards reduced delirium duration, although the effect on delirium severity remains uncertain. Further research should focus on implementation and detailed analysis of the components of the interventions to support more effective, tailored practice recommendations.

[Nonpharmaceutical concepts for prevention and treatment of delirium]

BACKGROUND

Cognitive impairment is common among older patients in German hospitals (40%). Dementia, other brain diseases and frailty significantly increase the risk of delirium and pose great challenges to interdisciplinary and interprofessional teams. Delirium prevention is achievable but requires complex interdepartmental strategies with specific components for timely recognition of the individual delirium risk, to carry out structured and sustained implementation of appropriate measures for delirium prevention as well as prompt etiological diagnostics and immediate treatment when delirium occurs.

OBJECTIVE

The present work aims to shed light on the role of interprofessional and interdisciplinary collaboration in evidence-based, nonpharmacological delirium prevention programs.

MATERIAL AND METHODS

Narrative review of international best practice programs.

RESULTS

Nonpharmacological prevention of delirium is effective but requires differentiated risk identification, regular delirium screening and daily targeted cognitive activation and sleep promotion. This can only be achieved in close interprofessional collaboration and is mostly carried out interdepartmentally by specialized teams.

DISCUSSION

Interprofessional multicomponent programs for delirium prevention hold the potential to reduce delirium and complication rates in older high-risk patients in regular care, thereby improving treatment and long-term quality of life. Additional interprofessional delirium prevention teams are deployed in different settings simultaneously and provide regular training on optimal delirium management. Demonstration of the effectiveness of cross-setting programs requires large multicenter studies and is therefore particularly laborious.

Non-pharmacological interventions for preventing delirium in hospitalised non-ICU patients

BACKGROUND

Delirium is an acute neuropsychological disorder that is common in hospitalised patients. It can be distressing to patients and carers and it is associated with serious adverse outcomes. Treatment options for established delirium are limited and so prevention of delirium is desirable. Non-pharmacological interventions are thought to be important in delirium prevention.  OBJECTIVES: To assess the effectiveness of non-pharmacological interventions designed to prevent delirium in hospitalised patients outside intensive care units (ICU).

SEARCH METHODS

We searched ALOIS, the specialised register of the Cochrane Dementia and Cognitive Improvement Group, with additional searches conducted in MEDLINE, Embase, PsycINFO, CINAHL, LILACS, Web of Science Core Collection, ClinicalTrials.gov and the World Health Organization Portal/ICTRP to 16 September 2020. There were no language or date restrictions applied to the electronic searches, and no methodological filters were used to restrict the search.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of single and multicomponent non-pharmacological interventions for preventing delirium in hospitalised adults cared for outside intensive care or high dependency settings. We only included non-pharmacological interventions which were designed and implemented to prevent delirium.  DATA COLLECTION AND ANALYSIS: Two review authors independently examined titles and abstracts identified by the search for eligibility and extracted data from full-text articles. Any disagreements on eligibility and inclusion were resolved by consensus. We used standard Cochrane methodological procedures. The primary outcomes were: incidence of delirium; inpatient and later mortality; and new diagnosis of dementia. We included secondary and adverse outcomes as pre-specified in the review protocol. We used risk ratios (RRs) as measures of treatment effect for dichotomous outcomes and between-group mean differences for continuous outcomes. The certainty of the evidence was assessed using GRADE. A complementary exploratory analysis was undertaker using a Bayesian component network meta-analysis fixed-effect model to evaluate the comparative effectiveness of the individual components of multicomponent interventions and describe which components were most strongly associated with reducing the incidence of delirium.

MAIN RESULTS

We included 22 RCTs that recruited a total of 5718 adult participants. Fourteen trials compared a multicomponent delirium prevention intervention with usual care. Two trials compared liberal and restrictive blood transfusion thresholds. The remaining six trials each investigated a different non-pharmacological intervention. Incidence of delirium was reported in all studies.  Using the Cochrane risk of bias tool, we identified risks of bias in all included trials. All were at high risk of performance bias as participants and personnel were not blinded to the interventions. Nine trials were at high risk of detection bias due to lack of blinding of outcome assessors and three more were at unclear risk in this domain.  Pooled data showed that multi-component non-pharmacological interventions probably reduce the incidence of delirium compared to usual care (10.5% incidence in the intervention group, compared to 18.4% in the control group, risk ratio (RR) 0.57, 95% confidence interval (CI) 0.46 to 0.71, I2 = 39%; 14 studies; 3693 participants; moderate-certainty evidence, downgraded due to risk of bias).  There may be little or no effect of multicomponent interventions on inpatient mortality compared to usual care (5.2% in the intervention group, compared to 4.5% in the control group, RR 1.17, 95% CI 0.79 to 1.74, I2 = 15%; 10 studies; 2640 participants; low-certainty evidence downgraded due to inconsistency and imprecision).  No studies of multicomponent interventions reported data on new diagnoses of dementia.  Multicomponent interventions may result in a small reduction of around a day in the duration of a delirium episode (mean difference (MD) -0.93, 95% CI -2.01 to 0.14 days, I2 = 65%; 351 participants; low-certainty evidence downgraded due to risk of bias and imprecision). The evidence is very uncertain about the effect of multicomponent interventions on delirium severity (standardised mean difference (SMD) -0.49, 95% CI -1.13 to 0.14, I2=64%; 147 participants; very low-certainty evidence downgraded due to risk of bias and serious imprecision). Multicomponent interventions may result in a reduction in hospital length of stay compared to usual care (MD -1.30 days, 95% CI -2.56 to -0.04 days, I2=91%; 3351 participants; low-certainty evidence downgraded due to risk of bias and inconsistency), but little to no difference in new care home admission at the time of hospital discharge (RR 0.77, 95% CI 0.55 to 1.07; 536 participants; low-certainty evidence downgraded due to risk of bias and imprecision). Reporting of other adverse outcomes was limited.  Our exploratory component network meta-analysis found that re-orientation (including use of familiar objects), cognitive stimulation and sleep hygiene were associated with reduced risk of incident delirium. Attention to nutrition and hydration, oxygenation, medication review, assessment of mood and bowel and bladder care were probably associated with a reduction in incident delirium but estimates included the possibility of no benefit or harm.  Reducing sensory deprivation, identification of infection, mobilisation and pain control all had summary estimates that suggested potential increases in delirium incidence, but the uncertainty in the estimates was substantial.  Evidence from two trials suggests that use of a liberal transfusion threshold over a restrictive transfusion threshold probably results in little to no difference in incident delirium (RR 0.92, 95% CI 0.62 to 1.36; I2 = 9%; 294 participants; moderate-certainty evidence downgraded due to risk of bias).  Six other interventions were examined, but evidence for each was limited to single studies and we identified no evidence of delirium prevention.  AUTHORS' CONCLUSIONS: There is moderate-certainty evidence regarding the benefit of multicomponent non-pharmacological interventions for the prevention of delirium in hospitalised adults, estimated to reduce incidence by 43% compared to usual care. We found no evidence of an effect on mortality. There is emerging evidence that these interventions may reduce hospital length of stay, with a trend towards reduced delirium duration, although the effect on delirium severity remains uncertain. Further research should focus on implementation and detailed analysis of the components of the interventions to support more effective, tailored practice recommendations.

Mitigating the stress response to improve outcomes for older patients undergoing emergency surgery with the addition of beta-adrenergic blockade

As population age, healthcare systems and providers are likely to experience a substantial increase in the proportion of elderly patients requiring emergency surgery. Emergency surgery, compared with planned surgery, is strongly associated with increased risks of adverse postoperative outcomes due to the short time available for diagnosis, optimization, and intervention in patients presenting with physiological derangement. These patient populations, who are often frail and burdened with a variety of co-morbidities, have lower reserves to deal with the stress of the acute condition and the required emergency surgical intervention. In this review article, we discuss topical areas where mitigation of the physiological stress posed by the acute condition and asociated surgical intervention may be feasible. We consider the impact of the adrenergic response and use of beta blockers for these high-risk patients and discuss common risk factors such as frailty and delirium. A proactive multidisciplinary approach to peri-operative care aimed at mitigation of the stress response and proactive management of common conditions in the older emergency surgical patient could yield more favorable outcomes.

The Prevention of Delirium system of care for older patients admitted to hospital for emergency care: the POD research programme including feasibility RCT

Background

Delirium is a distressing, common and serious condition in older people in hospital. Evidence suggests that it could be prevented in about one-third of patients using multicomponent interventions targeting delirium risk factors, but these interventions are not yet routinely available in the NHS.

Objective

The objective was to improve delirium prevention for older people admitted to the NHS.

Design

Project 1 comprised case studies employing qualitative methods (observation, interviews, workshops) in three NHS hospitals to develop the Prevention of Delirium system of care. Project 2 comprised case studies using mixed methods in five NHS hospitals to test the Prevention of Delirium implementation, feasibility and acceptability, and to modify the Prevention of Delirium system of care. Project 3 comprised a multicentre, cluster randomised, controlled, pragmatic feasibility study in eight hospitals, with embedded economic evaluation, to investigate the potential clinical effectiveness and cost-effectiveness of the Prevention of Delirium system of care, compared with standard care, among older patients admitted to hospital for emergency care. The primary objectives related to gathering information to design a definitive trial. Criteria for progression to a definitive trial were as follows: a minimum of six wards (75%) completing the Prevention of Delirium manual milestone checklist and an overall recruitment rate of at least 10% of the potential recruitment pool.

Setting

This study was set in NHS general hospitals.

Participants

In project 1, participants were staff, volunteers, and patient and carer representatives. In project 2, participants were staff, volunteers, patients and carers. In project 3, participants were older patients admitted to elderly care and orthopaedic trauma wards.

Intervention

The developed intervention (i.e. the Prevention of Delirium system of care).

Main outcome measures

For the feasibility study (project 3), the primary outcome measure was the Confusion Assessment Method. The secondary outcome measures were the Nottingham Extended Activities of Daily Living scale, the Clinical Anxiety Scale and the Geriatric Depression Scale Short Form.

Results

Project 1: understanding of delirium prevention was poor. Drawing on evidence, and working with ward teams, we developed the Prevention of Delirium system of care, which targeted 10 delirium risk factors. This multicomponent intervention incorporated systems and mechanisms to introduce and embed delirium prevention into routine ward practices. Project 2: five out of six wards implemented or partially implemented the Prevention of Delirium intervention. A prominent role for hospital volunteers was intended, but most wards were unable to recruit or sustain the numbers needed. We identified four conditions necessary to implement and deliver the Prevention of Delirium intervention: (1) commitment of senior nurse, (2) a named person to drive implementation forward, (3) dedicated time (1 day per week) of an experienced nurse to lead implementation and (4) adequate ward staffing levels. Overall, the intervention was acceptable to staff, volunteers, patients and carers, and did not increase nursing staff workload. In the light of these findings, the Prevention of Delirium system of care was modified for use in project 3. Project 3: 16 wards in eight hospitals (two wards per hospital) were recruited. Out of 4449 patients screened, 3274 (73.6%) were eligible and 713 were registered, resulting in a recruitment rate of 16.0%. Thirty-three (4.6%) participants withdrew. The screened and registered participants were similar, but some between-treatment group imbalances were noted among those registered to the trial. All eight wards allocated to the intervention group completed the Prevention of Delirium manual milestone checklist and delivered the Prevention of Delirium intervention (median time 18.6 weeks for implementation). Overall, fidelity to the intervention was assessed as being high in two wards, medium in five wards and low in one ward. Of the expected 5645 Confusion Assessment Method delirium assessments, 5065 (89.7%) were completed during the first 10 days of admission. The rates of return of the patient-reported questionnaire booklets were 98.0% at baseline, 81.8% at 30 days and 70.5% at 3 months. The return rate of the EuroQol-5 Dimensions questionnaire was 98.6% at baseline, 77.5% at 1 month and 65.3% at 3 months (94–98% fully completed). The completion rate of the resource use questionnaire was lower (48.7%). The number of people with new-onset delirium at 10 days was 24 (7.0%) in the Prevention of Delirium group and 33 (8.9%) in the control group. Multilevel logistic regression analysis showed that participants in the Prevention of Delirium group had non-significant lower odds of developing delirium (odds ratio 0.68, 95% confidence interval 0.37 to 1.26; p = 0.2225). The average cost of the Prevention of Delirium intervention was estimated as £10.98 per patient and the mean costs for the Prevention of Delirium and usual-care groups were £5332 and £4412, respectively, with negligible between-group differences in quality-adjusted life-years. There was conflicting evidence from the trial- and model-based analyses relating to the cost-effectiveness of the Prevention of Delirium intervention. Given this, and in view of issues with the data (e.g. high levels of missingness), the results from the economic evaluation are highly uncertain. The criteria for continuation to a future definitive randomised controlled trial were met. Such a trial would need to recruit 5200 patients in 26 hospital clusters (200 patients per cluster).

Conclusions

The Prevention of Delirium system of care was successfully developed, and a multicentre feasibility study showed that the intervention is capable of implementation and delivery in routine care, with acceptable intervention fidelity and preliminary estimate of effectiveness.

Limitations

A prominent role for volunteers was originally intended in the Prevention of Delirium system of care, but only three of the eight wards allocated to the trial intervention group involved volunteers.

Future work

The findings indicate that a definitive multicentre evaluation of the Prevention of Delirium system of care should be designed and conducted to obtain robust estimates of clinical effectiveness and cost-effectiveness.

Trial registration

Current Controlled Trials ISRCTN28213290 (project 1), ISRCTN65924234 (project 2) and ISRCTN01187372 (project 3).

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 9, No. 4. See the NIHR Journals Library website for further project information.

A multicentre, pragmatic, cluster randomised, controlled feasibility trial of the POD system of care

OBJECTIVE

to provide a preliminary estimate of the effectiveness of the prevention of delirium (POD) system of care in reducing incident delirium in acute hospital wards and gather data for a future definitive randomised controlled trial.

DESIGN

cluster randomised and controlled feasibility trial.

SETTING

sixteen acute care of older people and orthopaedic trauma wards in eight hospitals in England and Wales.

PARTICIPANTS

patients 65 years and over admitted to participating wards during the trial period.

INTERVENTIONS

participating wards were randomly assigned to either the POD programme or usual care, determined by existing local policies and practices. The POD programme is a manualised multicomponent delirium prevention intervention that targets 10 risk factors for delirium. The intervention wards underwent a 6-month implementation period before trial recruitment commenced. Main outcome measure incidence of new-onset delirium measured using the Confusion Assessment Method (CAM) measured daily for up to 10 days post consent.

RESULTS

out of 4449, 3274 patients admitted to the wards were eligible. In total, 714 patients consented (713 registered) to the trial, thirty-three participants (4.6%) withdrew. Adherence to the intervention was classified as at least medium for seven wards. Rates of new-onset delirium were lower than expected and did not differ between groups (24 (7.0%) of participants in the intervention group versus 33 (8.9%) in the control group; odds ratio (95% confidence interval) 0.68 (0.37-1.26); P = 0.2225).

CONCLUSIONS

based on these findings, a definitive trial is achievable and would need to recruit 5220 patients in 26 two-ward hospital clusters. Trial registration: ISRCTN01187372. Registered 13 March 2014.

Investigation of ward fidelity to a multicomponent delirium prevention intervention during a multicentre, pragmatic, cluster randomised, controlled feasibility trial

BACKGROUND

delirium is a frequent complication of hospital admission for older people and can be reduced by multicomponent interventions, but implementation and delivery of such interventions is challenging.

OBJECTIVE

to investigate fidelity to the prevention of delirium system of care within a multicentre, pragmatic, cluster randomised, controlled feasibility trial.

SETTING

five care of older people and three orthopaedic trauma wards in eight hospitals in England and Wales.

DATA COLLECTION

research nurse observations of ward practice; case note reviews and examination of documentation.

ASSESSMENT

10 health care professionals with experience in older people's care assessed the fidelity to 21 essential implementation components within four domains: intervention installation (five items; maximum score = 5); intervention delivery (12 items; maximum score = 48); intervention coverage (three items; maximum score = 16); and duration of delivery (one item; maximum score = 1).

RESULTS

the mean score (range) for each domain was: installation 4.5 (3.5-5); delivery 32.6 (range 27.3-38.3); coverage 7.9 (range 4.2-10.1); and duration 0.38 (0-1). Of the 10 delirium risk factors, infection, nutrition, hypoxia and pain were the most and cognitive impairment, sensory impairment and multiple medications the least consistently addressed. Overall fidelity to the intervention was assessed as high (≥80%) in two wards, medium (51-79%) in five wards and low (≤50%) in one ward.

CONCLUSION

the trial was designed as a pragmatic evaluation, and the findings of medium intervention fidelity are likely to be generalisable to delirium prevention in routine care and provide an important context to interpret the trial outcomes.

Prospective Evaluation of Delirium in Geriatric Patients Undergoing Emergency General Surgery

BACKGROUND

The prevalence of delirium and its impact on outcomes after emergency general surgery (EGS) remain unexplored. The aims of our study were to assess the impact of frailty on delirium and the impact of delirium on outcomes in geriatric EGS patients.

STUDY DESIGN

We performed a 1-year (2017) prospective cohort analysis of all geriatric (age ≥ 65 years) patients who underwent EGS. Frailty was calculated using the Emergency General Surgery-Specific Frailty Index (ESFI). Delirium was assessed using the Confusion Assessment Method (CAM). Patients were dichotomized as delirious or non-delirious. We performed regression analysis controlling for demographics, admission vitals, American Society of Anesthesiologists (ASA) score, comorbidity, and the diagnosis and type of surgery.

RESULTS

A total of 163 patients underwent emergency general surgery and were included. Mean age was 71 ± 7 years, and 59% were male. Overall, the incidence of postoperative delirium was 26%. Patients who developed postoperative delirium were more likely to be frail (40% vs 14%, p < 0.01), on more than 3 medications (29% vs 18%, p < 0.01), and were more likely to have 3 or more comorbidities (32% vs 21%, p < 0.01). On regression analysis, frail status (odds ratio [OR] 3.7 [2.4-4.2], p < 0.01) and receiving more than 3 medications (OR 1.3 [range 1.1-1.4], p < 0.01) were independent predictors of developing postoperative delirium. An episode of delirium was associated with longer hospital length of stay (LOS) (6 days vs 3 days, p < 0.01), higher odds of ICU admission (OR 2 [1.3-4.5], p < 0.01), longer ICU LOS (2 days vs 1 day, p < 0.01), and higher odds of unplanned intubation (OR 1.8 [1.2-3.4], p < 0.01).

CONCLUSIONS

The incidence of delirium after EGS was 26%. Frailty and polypharmacy were associated with increased risk of delirium. Delirium appears to be associated with higher rates of in-hospital adverse events.

Effect of the Tailored, Family-Involved Hospital Elder Life Program on Postoperative Delirium and Function in Older Adults: A Randomized Clinical Trial

IMPORTANCE

Postoperative delirium (POD) is a common condition for older adults, contributing to their functional decline.

OBJECTIVE

To investigate the effectiveness of the Tailored, Family-Involved Hospital Elder Life Program (t-HELP) for preventing POD and functional decline in older patients after a noncardiac surgical procedure.

DESIGN, SETTING, AND PARTICIPANTS

A 2-arm, parallel-group, single-blind, cluster randomized clinical trial was conducted from August 24, 2015, to February 28, 2016, on 6 surgical floors (gastric, colorectal, pancreatic, biliary, thoracic, and thyroid) of West China Hospital in Chengdu, China. Eligible participants (n = 281) admitted to each of the 6 surgical floors were randomized into a nursing unit providing t-HELP (intervention group) or a nursing unit providing usual care (control group). All randomized patients were included in the intention-to-treat analyses for the primary outcome of POD incidence. Statistical analysis was performed from April 3, 2016, to December 30, 2017.

INTERVENTIONS

In addition to receiving usual care, all participants in the intervention group received the t-HELP protocols, which addressed each patient's risk factor profile. Besides nursing professionals, family members and paid caregivers were involved in the delivery of many of the program interventions.

MAIN OUTCOMES AND MEASURES

The primary outcome was the incidence of POD, evaluated with the Confusion Assessment Method. Secondary outcomes included the pattern of functional and cognitive changes (activities of daily living [ADLs], instrumental activities of daily living [IADLs], Short Portable Mental Status Questionnaire [SPMSQ]) from hospital admission to 30 days after discharge, and the length of hospital stay (LOS).

RESULTS

Of the 475 patients screened for eligibility, 281 (171 [60.9%] male, mean [SD] age 74.7 [5.2] years) were enrolled and randomized to receive t-HELP (n = 152) or usual care (n = 129). Postoperative delirium occurred in 4 participants (2.6%) in the intervention group and in 25 (19.4%) in the control group, with a relative risk of 0.14 (95% CI, 0.05-0.38). The number needed to treat to prevent 1 case of POD was 5.9 (95% CI, 4.2-11.1). Participants in the intervention group compared with the control group showed less decline in physical function (median [interquartile range] for ADLs: -5 [-10 to 0] vs -20 [-30 to -10]; P < .001; for IADLs: -2 [-2 to 0] vs -4 [-4 to -2]; P < .001) and cognitive function (for the SPMSQ level: 1 [0.8%] vs 8 [7.0%]; P = .009) at discharge, as well as shorter mean (SD) LOS (12.15 [3.78] days vs 16.41 [4.69] days; P < .001).

CONCLUSIONS AND RELEVANCE

The findings suggest that t-HELP, with family involvement at its core, is effective in reducing POD for older patients, maintaining or improving their physical and cognitive functions, and shortening the LOS. The results of this t-HELP trial may improve generalizability and increase the implementation of this program.

TRIAL REGISTRATION

Chinese Clinical Trial Registry Identifier: ChiCTR-POR-15006944.

Study protocol: ASCRIBED: the impact of Acute SystematiC inflammation upon cerebRospinal fluId and blood BiomarkErs of brain inflammation and injury in dementia: a study in acute hip fracture patients

BACKGROUND

Hip fracture represents a substantial acute inflammatory trauma, which may constitute a significant insult to the degenerating brain. Research suggests that an injury of this kind can affect memory and thinking in the future but it is unclear whether, and how, inflammatory trauma injures the brain. The impact of Acute SystematiC inflammation upon cerebRospinal fluId and blood BiomarkErs of brain inflammation and injury in Dementia: a study in acute hip fracture patients (ASCRIBED) explores this relationship, to understand the effect of inflammation on the progression of dementia.

METHODS

This protocol describes a multi-centre sample collection observational study. The study utilises the unique opportunity provided by hip fracture operations undertaken via spinal anaesthesia to collect cerebrospinal fluid (CSF) and blood, to investigate the impact of acute brain inflammation caused by hip fracture on the exacerbation of dementia. We will recruit 200 hip fracture patients with a diagnosis or evidence of dementia; and 200 hip fracture patients without dementia. We will also recruit 'Suitable informants', individuals in regular contact with the patient, to provide further proxy evidence of a patient's potential cognitive decline. We will compare these 400 samples with existing CSF and blood samples from a cohort of dementia patients who had not experienced a systemic inflammatory response due to injury. This will provide a comparison between patients with and without dementia who are suffering a systemic inflammatory response; with stable patients living with dementia.

DISCUSSION

We will test the hypothesis that hip fracture patients living with dementia show elevated markers of brain inflammation, as well as neuronal injury and Alzheimer-related plaque pathology, in comparison to (1) stable patients living with dementia and (2) hip fracture patients without dementia, as measured by biomarkers in CSF and blood. The findings will address the hypothesis that systemic inflammatory events can exacerbate underlying dementia and inform the search for new treatments targeting inflammation in dementia.

TRIAL REGISTRATION

ISRCTN43803769 . Registered 11 May 2017.

Delirium risk in non-surgical patients: systematic review of predictive tools

OBJECTIVE

Delirium is a common, serious condition associated with poor hospital outcomes. Guidelines recommend screening for delirium risk to target diagnostic and/or prevention strategies. This study critically reviews multicomponent delirium risk prediction tools in adult non-surgical inpatients.

STUDY DESIGN

Systematic review of studies incorporating at least two clinical factors in a multicomponent tool predicting risk of delirium during hospital admission. Derivation and validation studies were included. Study design, risk factors and tool performance were extracted and tabulated, and study quality was assessed by CHARMS criteria.

DATA SOURCES

PubMed, Embase, PsycINFO, and Cumulative Index to Nursing Health Literature (CINAHL) to 11^th March 2018.

DATA SYNTHESIS

22 derivation studies enrolling 38,874 participants (9 with a validation component) and 4 additional validation studies were identified, from a range of ward types. All studies had at least moderate risk of bias. Older age and cognitive, functional and sensory impairment were important predisposing factors. Precipitating risk factors included infection, illness severity, renal and electrolyte disturbances. Tools mostly did not differentiate between predisposing and precipitating risk factors mathematically or conceptually Most tools showed fair to good discrimination, and identified more than half of older inpatients at risk.

CONCLUSIONS

Several validated delirium risk prediction tools can identify patients at increased risk of delirium, but do not provide clear advice for clinical application. Most recommended cut-points are sensitive but have low specificity. Implementation studies demonstrating how risk screening can better direct clinical interventions in specific clinical settings are needed to define the potential value of these tools.

Use of the confusion assessment method in multicentre delirium trials: training and standardisation

Background

Delirium occurs commonly in older adults and is associated with adverse outcomes. Multicentre clinical trials evaluating interventions to prevent delirium are needed. The Confusion Assessment Method (CAM) is a validated instrument for delirium detection. We hypothesised it would be possible for a large feasibility study to train a large number of research assistants, with varying experience levels, to conduct CAM assessments reliably in multiple hospital sites.

Methods

A standardised training programme was followed, incorporating structured training at a central location and at study sites. CAM practice sessions on both delirious and non-delirious patients by research assistants were conducted and, thereafter, there was ongoing inter-rater reliability assessment on the CAM between research assistant pairs at study sites. The setting was eight acute care hospitals in England and Wales. Participants were research assistants working on a multicentre feasibility study of delirium prevention. The measurement used was the Confusion Assessment Method.

Results

Thirty-seven research assistants were trained in CAM assessment and 33 returned training logs. The logs showed there was 100% overall agreement between research assistant pairs on 295 CAM assessments, of which 263 (89.2%) were negative for delirium and 32 (10.8%) were positive. In the course of the feasibility study, research assistants successfully completed 5065 (89.7%) of the 5645 expected CAM assessments, with minimal missing data.

Conclusion

Using the training methods described in this study, it is possible to achieve high quality delirium assessments for large numbers of patients with little missing data across geographically dispersed sites in multicentre studies. The standardisation of multisite delirium assessments is an important contribution to research methodology, and provides a much-needed advance for the field.

Trial registration

ISRCT ISRCTN01187372. Registered 13 March 2014.

The Person, Interactions and Environment Programme to improve care of people with dementia in hospital: a multisite study

Background

Improving the care of people with dementia on acute hospital wards is a policy priority. Person-centred care is a marker of care quality; delivering such care is a goal of service improvement.

Objectives

The Person, Interactions and Environment (PIE) Programme comprises an observation tool and a systematic approach to implement and embed a person-centred approach in routine care for hospitalised patients with dementia. The study aims were to evaluate PIE as a method to improve the care of older people with dementia on acute hospital wards, and develop insight into what person-centred care might look like in practice in this setting.

Methods

We performed a longitudinal comparative case study design in 10 purposively selected wards in five trusts in three English regions, alongside an embedded process evaluation. Data were collected from multiple sources: staff, patients, relatives, organisational aggregate information and documents. Mixed methods were employed: ethnographic observation; interviews and questionnaires; patient case studies (patient observation and conversations ‘in the moment’, interviews with relatives and case records); and patient and ward aggregate data. Data were synthesised to create individual case studies of PIE implementation and outcomes in context of ward structure, organisation, patient profile and process of care delivery. A cross-case comparison facilitated a descriptive and explanatory account of PIE implementation in context, the pattern of variation, what shaped it and the consequences flowing from it. Quantitative data were analysed using simple descriptive statistics. A qualitative data analysis employed grounded theory methods.

Results

The study furthered the understanding of the dimensions of care quality for older people with dementia on acute hospital wards and the environmental, organisational and cultural factors that shaped delivery. Only two wards fully implemented PIE, sustaining and embedding change over 18 months. The remaining wards either did not install PIE (‘non-implementers’) or were ‘partial implementers’. The interaction between micro-level contextual factors [aspects of leadership (drivers, facilitators, team, networks), fit with strategic initiatives and salience with valued goals] and meso- and macro-level organisational factors were the main barriers to PIE adoption. Evidence suggests that the programme, where implemented, directly affected improvements in ward practice, with a positive impact on the experiences of patients and caregivers, although the heterogeneity of need and severity of impairment meant that some of the more visible changes did not affect everyone equally.

Limitations

Although PIE has the potential to improve the care of people with dementia when implemented, findings are indicative only: data on clinical outcomes were not systematically collected, and PIE was not adopted on most study wards.

Research implications

Further research is required to identify more precisely the skill mix and resources necessary to provide person-focused care to hospitalised people with dementia, across the spectrum of need, including those with moderate and severe impairment. Implementing innovations to change practices in complex organisations requires a more in-depth understanding of the contextual factors that have an impact on the capacity of organisations to absorb and embed new practices.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

PERFECTED enhanced recovery (PERFECT-ER) care versus standard acute care for patients admitted to acute settings with hip fracture identified as experiencing confusion: study protocol for a feasibility cluster randomized controlled trial

BACKGROUND

Health and social care provision for an ageing population is a global priority. Provision for those with dementia and hip fracture has specific and growing importance. Older people who break their hip are recognised as exceptionally vulnerable to experiencing confusion (including but not exclusively, dementia and/or delirium and/or cognitive impairment(s)) before, during or after acute admissions. Older people experiencing hip fracture and confusion risk serious complications, linked to delayed recovery and higher mortality post-operatively. Specific care pathways acknowledging the differences in patient presentation and care needs are proposed to improve clinical and process outcomes.

METHODS

This protocol describes a multi-centre, feasibility, cluster-randomised, controlled trial (CRCT) to be undertaken across ten National Health Service hospital trusts in the UK. The trial will explore the feasibility of undertaking a CRCT comparing the multicomponent PERFECTED enhanced recovery intervention (PERFECT-ER), which acknowledges the differences in care needs of confused older patients experiencing hip fracture, with standard care. The trial will also have an integrated process evaluation to explore how PERFECT-ER is implemented and interacts with the local context. The study will recruit 400 hip fracture patients identified as experiencing confusion and will also recruit "suitable informants" (individuals in regular contact with participants who will complete proxy measures). We will also recruit NHS professionals for the process evaluation. This mixed methods design will produce data to inform a definitive evaluation of the intervention via a large-scale pragmatic randomised controlled trial (RCT).

DISCUSSION

The trial will provide a preliminary estimate of potential efficacy of PERFECT-ER versus standard care; assess service delivery variation, inform primary and secondary outcome selection, generate estimates of recruitment and retention rates, data collection difficulties, and completeness of outcome data and provide an indication of potential economic benefits. The process evaluation will enhance knowledge of implementation delivery and receipt.

TRIAL REGISTRATION

ISRCTN, 99336264 . Registered on 5 September 2016.

Effect of a Modified Hospital Elder Life Program on Delirium and Length of Hospital Stay in Patients Undergoing Abdominal Surgery: A Cluster Randomized Clinical Trial

Importance

Older patients undergoing abdominal surgery commonly experience preventable delirium, which extends their hospital length of stay (LOS).

Objective

To examine whether a modified Hospital Elder Life Program (mHELP) reduces incident delirium and LOS in older patients undergoing abdominal surgery.

Design, Setting, and Participants

This cluster randomized clinical trial of 577 eligible patients enrolled 377 older patients (≥65 years of age) undergoing gastrectomy, pancreaticoduodenectomy, and colectomy at a 2000-bed urban medical center in Taipei, Taiwan, from August 1, 2009, through October 31, 2012. Consecutive older patients scheduled for elective abdominal surgery with expected LOS longer than 6 days were enrolled, with a recruitment rate of 65.3%. Participants were cluster randomized by room to receive the mHELP or usual care.

Interventions

The intervention (implemented by an mHELP nurse) consisted of 3 protocols administered daily: orienting communication, oral and nutritional assistance, and early mobilization. Intervention group participants received all 3 mHELP protocols postoperatively, in addition to usual care, as soon as they arrived in the inpatient ward and until hospital discharge. Adherence to protocols was tracked daily.

Main Outcomes and Measures

Presence of delirium was assessed daily by 2 trained nurses who were masked to intervention status by using the Confusion Assessment Method. Data on LOS were abstracted from the medical record.

Results

Of 577 eligible patients, 377 (65.3%) were enrolled and randomly assigned to the mHELP (n = 197; mean [SD] age, 74.3 [5.8] years; 111 [56.4%] male) or control (n = 180; mean [SD] age, 74.8 [6.0] years; 103 [57.2%] male) group. Postoperative delirium occurred in 13 of 196 (6.6%) mHELP participants vs 27 of 179 (15.1%) control individuals, representing a relative risk of 0.44 in the mHELP group (95% CI, 0.23-0.83; P = .008). Intervention group participants received the mHELP for a median of 7 days (interquartile range, 6-10 days) and had a shorter median LOS (12.0 days) than control participants (14.0 days) (P = .04).

Conclusions and Relevance

For older patients undergoing abdominal surgery who received the mHELP, the odds of delirium were reduced by 56% and LOS was reduced by 2 days. Our findings support using the mHELP to advance postoperative care for older patients undergoing major abdominal surgery.

Trial Registration

clinicaltrials.gov Identifier: NCT01045330.

Analysis of multi-dimensional contemporaneous EHR data to refine delirium assessments

Delirium is a potentially lethal condition of altered mental status, attention, and level of consciousness with an acute onset and fluctuating course. Its causes are multi-factorial, and its pathophysiology is not well understood; therefore clinical focus has been on prevention strategies and early detection. One patient evaluation technique in routine use is the Confusion Assessment Method (CAM): a relatively simple test resulting in 'positive', 'negative' or 'unable-to-assess' (UTA) ratings. Hartford Hospital nursing staff use the CAM regularly on all non-critical care units, and a high frequency of UTA was observed after reviewing several years of records. In addition, patients with UTA ratings displayed poor outcomes such as in-hospital mortality, longer lengths of stay, and discharge to acute and long term care facilities. We sought to better understand the use of UTA, especially outside of critical care environments, in order to improve delirium detection throughout the hospital. An unsupervised clustering approach was used with additional, concurrent assessment data available in the EHR to categorize patient visits with UTA CAMs. The results yielded insights into the most common situations in which the UTA rating was used (e.g. impaired verbal communication, dementia), suggesting potentially inappropriate ratings that could be refined with further evaluation and remedied with updated clinical training. Analysis of the patient clusters also suggested that unrecognized delirium may contribute to the poor outcomes associated with the use of UTA. This method of using temporally related high dimensional EHR data to illuminate a dynamic medical condition could have wider applicability.

Interventions for preventing delirium in hospitalised non-ICU patients

BACKGROUND

Delirium is a common mental disorder, which is distressing and has serious adverse outcomes in hospitalised patients. Prevention of delirium is desirable from the perspective of patients and carers, and healthcare providers. It is currently unclear, however, whether interventions for preventing delirium are effective.

OBJECTIVES

To assess the effectiveness of interventions for preventing delirium in hospitalised non-Intensive Care Unit (ICU) patients.

SEARCH METHODS

We searched ALOIS - the Cochrane Dementia and Cognitive Improvement Group's Specialized Register on 4 December 2015 for all randomised studies on preventing delirium. We also searched MEDLINE (Ovid SP), EMBASE (Ovid SP), PsycINFO (Ovid SP), Central (The Cochrane Library), CINAHL (EBSCOhost), LILACS (BIREME), Web of Science core collection (ISI Web of Science), ClinicalTrials.gov and the WHO meta register of trials, ICTRP.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of single and multi- component non-pharmacological and pharmacological interventions for preventing delirium in hospitalised non-ICU patients.

DATA COLLECTION AND ANALYSIS

Two review authors examined titles and abstracts of citations identified by the search for eligibility and extracted data independently, with any disagreements settled by consensus. The primary outcome was incidence of delirium; secondary outcomes included duration and severity of delirium, institutional care at discharge, quality of life and healthcare costs. We used risk ratios (RRs) as measures of treatment effect for dichotomous outcomes; and between group mean differences and standard deviations for continuous outcomes.

MAIN RESULTS

We included 39 trials that recruited 16,082 participants, assessing 22 different interventions or comparisons. Fourteen trials were placebo-controlled, 15 evaluated a delirium prevention intervention against usual care, and 10 compared two different interventions. Thirty-two studies were conducted in patients undergoing surgery, the majority in orthopaedic settings. Seven studies were conducted in general medical or geriatric medicine settings.We found multi-component interventions reduced the incidence of delirium compared to usual care (RR 0.69, 95% CI 0.59 to 0.81; seven studies; 1950 participants; moderate-quality evidence). Effect sizes were similar in medical (RR 0.63, 95% CI 0.43 to 0.92; four studies; 1365 participants) and surgical settings (RR 0.71, 95% CI 0.59 to 0.85; three studies; 585 participants). In the subgroup of patients with pre-existing dementia, the effect of multi-component interventions remains uncertain (RR 0.90, 95% CI 0.59 to 1.36; one study, 50 participants; low-quality evidence).There is no clear evidence that cholinesterase inhibitors are effective in preventing delirium compared to placebo (RR 0.68, 95% CI, 0.17 to 2.62; two studies, 113 participants; very low-quality evidence).Three trials provide no clear evidence of an effect of antipsychotic medications as a group on the incidence of delirium (RR 0.73, 95% CI, 0.33 to 1.59; 916 participants; very low-quality evidence). In a pre-planned subgroup analysis there was no evidence for effectiveness of a typical antipsychotic (haloperidol) (RR 1.05, 95% CI 0.69 to 1.60; two studies; 516 participants, low-quality evidence). However, delirium incidence was lower (RR 0.36, 95% CI 0.24 to 0.52; one study; 400 participants, moderate-quality evidence) for patients treated with an atypical antipsychotic (olanzapine) compared to placebo (moderate-quality evidence).There is no clear evidence that melatonin or melatonin agonists reduce delirium incidence compared to placebo (RR 0.41, 95% CI 0.09 to 1.89; three studies, 529 participants; low-quality evidence).There is moderate-quality evidence that Bispectral Index (BIS)-guided anaesthesia reduces the incidence of delirium compared to BIS-blinded anaesthesia or clinical judgement (RR 0.71, 95% CI 0.60 to 0.85; two studies; 2057 participants).It is not possible to generate robust evidence statements for a range of additional pharmacological and anaesthetic interventions due to small numbers of trials, of variable methodological quality.

AUTHORS' CONCLUSIONS

There is strong evidence supporting multi-component interventions to prevent delirium in hospitalised patients. There is no clear evidence that cholinesterase inhibitors, antipsychotic medication or melatonin reduce the incidence of delirium. Using the Bispectral Index to monitor and control depth of anaesthesia reduces the incidence of postoperative delirium. The role of drugs and other anaesthetic techniques to prevent delirium remains uncertain.