Relationships Of Preoperative Gut Microbiota And Postoperative Nausea And Vomiting In Female Patients Undergoing Thyroid Cancer Surgery

ObjectiveThis study mainly explored the relationships of preoperative and postoperative nausea and vomiting（PONV）in female patients undergoing thyroid cancer surgery,and the possible relationship between the composition of gut microbiota and PONV,so as to provide a new theoretical basis for the prevention of the occurrence and development of PONV.MethodsThis is a prospective observational clinical study.76 patients selected from Fujian Provincial Hospital were scheduled for elective thyroidectomy under general anesthesia from June 2020 to December 2020.Baseline data of patients were collected,including Age,BMI,ASA grade,smoking history,surgical history,PONV history,history of motion sickness,history of morning sickness,PONV risk assessment（Apfel score）,Self-Rating Anxiety Scale（SAS）,Pittsburgh Sleep Quality Index（PSQI）,ST.Mary’s Hospital sleep questionnaire 24 hours before surgery,PONV grade and visual analog scale of pain（VAS）.Fecal samples were collected the day before the surgery.All patients were anesthetized with standardized anesthesia plan.The PONV condition 24h after operation was observed.PONV were evaluated according to WHO nausea and vomiting rating.As long as the patient’s 24h postoperative nausea and vomiting rating was more than 1,the patient was considered to have PONV,and according to this result,the patients were divided into PONV group and non-PONV group.The gut microbiota community structure of PONV group and non-PONV group was analyzed by absolute quantitative sequencing of intestinal microorganism 16S amplica,and the important microorganisms related to the occurrence and development of PONV were explored by bioinformatics method,and the correlation between preoperative gut microbiota and PONV was further explored.ResultsThis study initially recruited 76 patients,10 of whom did not receive preoperative stool samples and were excluded.In the end,a total of 66 patients were included in the study.Among the 66 patients,31 patients（46.97%）developed PONV 24 hours after surgery,and 35 patients（53.03%）did not develop PONV.1.Baseline data of PONV group and non-PONV group were analyzed.There were no statistically significant differences in age,BMI,PONV risk score（Apfel score）,PSQI rating,duration of surgical anesthesia,total amount of sufentanil and postoperative pain VAS score between the two groups（P>0.05）.SAS anxiety rating of PONV group was higher than that of non-PONV group,and the difference was statistically significant（P=0.044）.2.There were significant differences in gut microbiota structure between PONV group and non-PONV group.There was no significant difference in gut microbiota diversity between PONV group and non-PONV group（P>0.05）.The abundance of fecal microorganisms in the PONV group was significantly reduced.At the order level,while the relative abundance of Bifidobacteriales in the PONV group was reduced（P=0.040）.At the family level,the relative abundance of Bifidobacteriaceae in the PONV group was reduced（P=0.040）.At the genus level,Anaerovorax、Butyricimonas、Gardnerella with higher relative abundance（P=0.031,0.039,0.045）and Bifidobacterium with lower relative abundance（P=0.040）.3.Correlation analysis was conducted between gut microbiota and clinical data of patients.Correlation analysis of gut microbiota and clinical data showed that age,BMI,SAS rating,ST.Mary’s sleep questionnaire score and abundance of Bifidobacteriales were not correlated（P>0.05）.The abundance of Bifidobacteriales was negatively correlated with the PSQI rating（r=-0.256,P=0.047）.4.Correlation analysis was performed on the influencing factors of PONV.It was found that there was no correlation between the occurrence of PONV and BMI APFEL score,total amount of sufentanil and postoperative pain VAS and PONV.The evaluation level of SAS was positively correlated with the occurrence of PONV（r=0.305,P=0.022）.The abundance of Bifidobacteriales was negatively correlated with the occurrence of PONV（r=-0.325,P=0.016）,and was negatively correlated with the severity of nausea and vomiting（r=-0.308,P=0.021）.5.Multivariate regression analysis of the possible influencing factors of PONV.It showed that age,SAS rating was independent risk factors for PONV（OR=0.9388,P=0.045;OR=1.109,P=0.017）,and the following prediction equation was obtained:p/（1-p）=e^{-1.345-0.064*age+0.103*SAS},which predict PONV occurrence rate in non-smoking female patients during thyroidectomy in Fujian Provincial Hospital.Conclusions1.In this study,16S absolute quantitative sequencing was used to comprehensively analyze the preoperative gut microbiota structure of patients in PONV group and non-PONV group,and it was found that Bifidobacteriales was the main species leading to differences between the PONV group and the non-PONV group.The abundance of Bifidobacteriales was negatively correlated with the occurrence and severity of PONV.The results of our study provide a theoretical basis for the prevention of PONV by regulating gut microbiota.2.Age and anxiety rating may be independent risk factors for PONV in female patients undergoing thyroid cancer surgery,which be one of the predictors of PONV in female patients undergoing thyroid cancer surgery.According to the results Logistic multivariate regression analysis,the following prediction equations are obtained:p/（1-p）=e^-1.345-0.064*Age+0.103*SAS),which predict PONV occurrence rate in non-smoking female patients during thyroidectomy in Fujian Provincial Hospital.