The effectiveness of nursing interventions for preventing postoperative delirium in older adults undergoing major orthopedic surgery: a systematic review

BACKGROUND: Postoperative delirium (POD) frequently occurs in elderly patients after major orthopedic surgery. Nurses play a key role in delivering non-pharmacological preventive interventions, but the evidence supporting their effectiveness varies. This systematic review aims to summarize current research on nursing interventions designed to reduce POD in older adults undergoing these surgeries. METHODS: We followed PRISMA 2020 guidelines to conduct a systematic search in five databases (CINAHL, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, and Google Scholar (as a supplementary source)) for studies published from 2010 to 2025. Eligible studies evaluated nursing-led interventions targeting delirium prevention in patients aged 65 years or older after major orthopedic surgery. Two reviewers independently screened using Rayyan [10] 529 records, reviewed full texts, and extracted data on study design, participants, interventions, and outcomes. Due to heterogeneity, a narrative synthesis approach was employed to analyze the data. Quality assessment used the Cochrane RoB 2 tool for randomized controlled trials and ROBINS-I [12] for non-randomized studies. RESULTS: Eight studies met inclusion criteria, including 3,018 participants. The designs comprised two randomized controlled trials, three quasi-experimental or cohort studies, two retrospective analyses, and one before-and-after study. Nurse-led multicomponent protocols, system-level interventions such as standardized orders, and single-component approaches like sensory aid management all showed statistically significant reductions in POD incidence. Absolute risk reductions ranged from 4.0% to 24.5%. Larger trials reported modest but statistically significant effects (for example, an odds ratio of 0.59 in an orthopedic subgroup), while smaller studies observed larger decreases. Variations in intervention types and outcome measures prevented meta-analysis. CONCLUSIONS: Nursing interventions, especially multicomponent protocols and systemic changes, may reduce postoperative delirium in older adults undergoing major orthopedic surgery. Even targeted single-component interventions suggest a potential to lower delirium rates meaningfully. Standardizing outcome measures in future studies would help enable outcome measures to enable meta-analyses and explore how best to implement these interventions in clinical settings. TRIAL REGISTRATION: PROSPERO CRD420251140913. Registered 05 September 2025. https://www.crd.york.ac.uk/PROSPERO/view/CRD420251140913.