Effectiveness of Bundle Interventions on ICU Delirium: A Meta-Analysis*

Objective: To evaluate the impact of bundle interventions on ICU delirium prevalence, duration, and other patients’ adverse outcomes. Data Sources: The Cochrane Library, PubMed, CINAHL, EMBASE, PsychINFO, and MEDLINE from January 2000 to July 2020. The protocol of the study was registered in International prospective register of systematic reviews (CRD42020163147). Study Selection: Randomized clinical trials or cohort studies that examined the following outcomes were included in the current study: ICU delirium prevalence and duration, proportion of patient-days with coma, ventilator-free days, mechanical ventilation days, ICU or hospital length of stay, and ICU or inhospital or 28-day mortality. Data Extraction: Using a standardized data-collection form, two authors screened the studies and extracted the data independently, and assessed the studies’ quality using the Modified Jadad Score Scale for randomized clinical trials and the Newcastle-Ottawa Scale for cohort studies. Data Synthesis: Eleven studies with a total of 26,384 adult participants were included in the meta-analysis. Five studies (three randomized clinical trials and two cohort studies) involving 18,638 patients demonstrated that ICU delirium prevalence was not reduced (risk ratio = 0.92; 95% CI, 0.68–1.24). Meta-analysis showed that the use of bundle interventions was not associated with shortening the duration of ICU delirium (mean difference = –1.42 d; 95% CI, –3.06 to 0.22; two randomized clinical trials and one cohort study), increasing ventilator-free days (mean difference = 1.56 d; 95% CI, –1.56 to 4.68; three randomized clinical trials), decreasing mechanical ventilation days (mean difference = –0.83 d; 95% CI, –1.80 to 0.14; four randomized clinical trials and two cohort studies), ICU length of stay (mean difference = –1.08 d; 95% CI, –2.16 to 0.00; seven randomized clinical trials and two cohort studies), and inhospital mortality (risk ratio = 0.86; 95% CI, 0.70–1.06; five randomized clinical trials and four cohort studies). However, bundle interventions are effective in reducing the proportion of patient-days experiencing coma (risk ratio = 0.47; 95% CI, 0.39–0.57; two cohort studies), hospital length of stay (mean difference = –1.47 d; 95% CI, –2.80 to –0.15; four randomized clinical trials and one cohort study), and 28-day mortality by 18% (risk ratio = 0.82; 95% CI, 0.69–0.99; three randomized clinical trials). Conclusions: This meta-analysis fails to support that bundle interventions are effective in reducing ICU delirium prevalence and duration, but supports that bundle interventions are effective in reducing the proportion of patient-days with coma, hospital length of stay, and 28-day mortality. Larger randomized clinical trials are needed to evaluate the impact of bundle interventions on ICU delirium and other clinical outcomes.