Ask an answerable question (PICO)：
About 80% of patients have experienced Chemotherapy-induced nausea and vomiting (CINV) through chemotherapy. 44% of patients used routine antiemetic drugs still experience CINV, despite the antiemetic prophylaxis. Serious CNIV has influenced the patient's appetite and leads to interruption or delay of treatment, affecting the treatment situation and quality of life.
Peppermint oil contains menthol, which releases serotonin through sniffing to inhibit vomiting, and inhibits substance P in the gastrointestinal tract to relaxes the smooth muscle to improve nausea and vomiting. The purpose of this study was to determine the effectiveness of the use of inhaled peppermint oil on CINV.
The Method and Analysis of Literature Review：
Tackling the clinical problems using Problem, Intervention, Comparison, and Outcome (PICO), respectively P is Chemotherapy; I is Peppermint Aromatherapy、Mentha Piperita Aromatherapy; O is Nause*Vomit*, Queasiness, "throw up", and CINV. The analysis uses Boolean algebra to search through Cochrane Library, Clinical Key, Embase, PubMed, DynaMed, JBI Database, CINAHL, MEDLINE, Google Scholar, and Chinese Electronic Periodical Services (CEPS). After analysis, two published studies are appraised ,each from SR and RCT.
Critical Appraisal：
After reviewing the studies for the benefit of inhaling peppermint oil, we included Toniolo et al. (2021) SR study which checked by CASP-Systematic-Review-Checklist-2018 critical appraisal score was 10/8 which had 80% coincidence rate and Ertürk et al. (2021) checked by JBI Critical Appraisal Checklist for quasi-experimental studies in the version of 2020 critical appraisal score was 9/9 which had 100% coincidence rate. Concerning the two studies, drip one to three drops of peppermint oil with cotton balls and inhale for 5-20 minutes can improve chemotherapy-induced nausea and vomiting. In order to know the effect of inhaling peppermint oil on CINV, 2 RCTs of inhaling peppermint oil in literature 1 and literature 2 were extracted for meta-analysis which three studies showed 95%CI [-0.70, -0.44],I2 =0%, p< 0.001 statistically significant and confirmed that inhaled peppermint oil aromatherapy could relieve nausea and vomiting caused by chemotherapy. According to the GRADE in the version of 2016, the quality of evidence was rated as 'moderate' and the recommended strength was 'strong'.
Clinical Application of Evidence：
The inclusion criteria for participation in the study were that the patients had to be 1.at least two remaining chemotherapy treatments, 2. experienced nausea of any severity during chemotherapy, 3.sense of smell function were normal. Exclusion criteria of the study:1. had any record of respiratory diseases, 2. Pregnancy, 3. no history of peppermint oil allergies or rejection.
In order to maintain the safety of subjects, peppermint oil allergy and olfactory evaluation before execution. All patients who received chemotherapy treatment inhaled for 10 minutes three times a day ; dropping three drops of peppermint oil into a cotton ball or a cotton piece with Aroma facemask Clip stuck to mask. After sniffing were to take the Visual Analog Scale (VAS) and the Index of Nausea, Vomiting, and Retching (INVR) survey.
Evaluation of Effectiveness：
Thirty-two subjects completed the study and were analyzed: 18 in the intervention group and 14 in the control group. In the VAS score, the mean value of the intervention group was 3.72, and the mean value of the control group was 7.14, with a statistically significant (p = 0.001). The mean value of the INVR scale in the intervention group was 5.11, and the mean value in the control group was 10.29, with a statistically significant effect (p = 0.003). According to the statistics, a total of 82 cases were accepted until November 2022. The average score of VAS was 3.52 ± 1.47, and the average score of INVR was 5.00 ± 3.29 to maintain the effect. This program's average satisfaction survey score was 97%, which gained recognition from subjects.
Conclusions and Recommendations：
According to the empirical literature, peppermint oil inhalation can relieve chemotherapy-induced nausea and vomiting with fewer side effects than antiemetic drugs. Sensitivity tests can rule out peppermint oil allergic reactions. Therefore, peppermint oil is safer and more economical, and it is also easier to get. In summary, while patient implements chemotherapy ,peppermint oil inhalation for CINV should be incorporated into health education measures by suggestion to reduce patients' physical discomfort and provide a comfortable environment.
