Influence of dental status on postoperative complications in major visceral surgical and organ transplantation procedures—the bellydent retrospective observational study
Authors: Spitzner Anastasia , Mieth Markus , Langan Ewan A. , Büchler Markus W. , Michalski Christoph , Billmann Franck 
Published: September 2024

Abstract
Purpose
The significance of dental status and oral hygiene on a range of medical conditions is well-recognised. However, the correlation between periodontitis, oral bacterial dysbiosis and visceral surgical outcomes is less well established. To this end, we study sought to determine the influence of dental health and oral hygiene on the rates of postoperative complications following major visceral and transplant surgery in an exploratory, single-center, retrospective, non-interventional study.

Methods
Our retrospective non-interventional study was conducted at the Department of General, Visceral, and Transplant Surgery, University Hospital Heidelberg, Germany. Patients operated on between January 2018 and December 2019 were retrospectively enrolled in the study based on inclusion (minimum age of 18 years, surgery at our Department, intensive care / IMC treatment after major surgery, availability of patient-specific preoperative dental status assessment, documentation of postoperative complications) and exclusion criteria (minor patients or legally incapacitated patients, lack of intensive care or intermediate care (IMC) monitoring, incomplete documentation of preoperative dental status, intestinal surgery with potential intraoperative contamination of the site by intestinal microbes, pre-existing preoperative infection, absence of data regarding the primary endpoints of the study). The primary study endpoint was the incidence of postoperative complications. Secondary study endpoints were: 30-day mortality, length of hospital stay, duration of intensive care stay, Incidence of infectious complications, the microbial spectrum of infectious complication. A bacteriology examination was added whenever possible (if and only if the examination was safe for the patient)for infectious complications.

Results
The final patient cohort consisted of 417 patients. While dental status did not show an influence (p = 0.73) on postoperative complications, BMI (p = 0.035), age (p = 0.049) and quick (p = 0.033) were shown to be significant prognostic factors. There was significant association between oral health and the rate of infectious complications for all surgical procedures (p = 0.034), excluding transplant surgery. However, this did not result in increased 30-day mortality rates, prolonged intensive care unit treatment or an increase in the length of hospital stay (LOS) for the cohort as a whole. In contrast there was a significant correlation between the presence of oral pathogens and postoperative complications for a group as a whole (p < 0.001) and the visceral surgery subgroup (p < 0.001). Whilst this was not the case in the cohort who underwent transplant surgery, there was a correlation between oral health and LOS in this subgroup (p = 0.040). Bacterial swabs supports the link between poor oral health and infectious morbidity.

Conclusions
Dental status was a significant predictor of postoperative infectious complications in this visceral surgery cohort. This study highlights the importance preoperative dental assessment and treatment prior to major surgery, particularly in the case of elective surgical procedures. Further research is required to determine the effect of oral health on surgical outcomes in order to inform future practice.

Trial registration
Trial registered under the ethics-number S-082/2022 (Ethic Committee of the University Heidelberg).