Effect of Lavender Oil on Preoperative Anxiety: Systematic Review and Meta-analysis.

PURPOSE: Surgical interventions are known to induce anxiety in patients due to the associated risks and potential complications. Various methods are employed to alleviate preoperative anxiety. This study aimed to investigate the impact of lavender oil application on the anxiety levels of patients scheduled for surgical procedures. DESIGN: Systematic review and meta-analysis. METHODS: Studies were accessed using the keywords "preoperative and lavender oil and stress" in Turkish and English between July 1 and 30, 2022, through PubMed (including MEDLINE), Cochrane, EBSCOhost, Web of Science, YÖK National Thesis Center, and Google Scholar. The standardized mean difference was calculated using random-effects models, and the Cochrane Collaboration tool was used to assess the risk of bias in each study. The study was prepared according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis checklist. FINDINGS: Twenty studies were included in the analysis. The anxiety level of the experimental group to which lavender oil was applied before the surgical intervention was significantly lower than that of the control group (standardized mean difference:-5.40; 95% CI: -8.76 to -2.04). CONCLUSION: Preoperative lavender oil application was found to be an effective method for relieving patients' anxiety. Lavender oil is thought to be a potential standalone treatment for preoperative anxiety.