Evaluation of the effectiveness of an aromatherapy treatment with lavender essential oil to reduce post-operative nausea and vomiting: study protocol of a randomised controlled trial

Background: The most common post-operative symptoms are nausea and vomiting. Aromatherapy has been shown to reduce post-operative nausea and vomiting and thus could be used as a complementary therapy to antiemetic drugs; however, no studies have considered the exclusive use of Lavender in these patients. The study’s aim is to assess aromatherapy in reducing nausea and vomiting in post-operative patients. Materials and Methods: A 2-arm randomised controlled interventional study was carried out in the Neurosurgery, General Surgery, Vascular Surgery, and Gynaecology facilities of the SS Antonio e Biagio e Cesare Arrigo Hospital of Alessandria. Study inclusion criteria: patients over the age of 18, who sign an informed consent form, have had an anaesthesiologic examination, have had general anaesthesia, and are clinically stable with a nausea score of NRS>0. Multiple instruments will be used, including a numerical rating scale, a Likert rating scale, and a Likert rating scale to assess Vomiting and the degree of satisfaction. Conclusions: The use of complementary non-pharmacological methods such as aromatherapy may help patients feel more comfortable in the post-operative period.