Preoperative and Postoperative Salivary Bacterial Counts in Infants Undergoing Cardiac Surgery: A Prospective Observational Study

Introduction: Postoperative pneumonia may develop in infants after cardiac surgery; however, only a few reports are available on perioperative oral bacteria in infants. This study aimed to examine preoperative and postoperative salivary bacterial counts in infants undergoing cardiac surgery. Materials and methods: The number of bacteria in the saliva of 105 infants (average age: 20 months) who underwent surgery for congenital heart disease was determined by culturing before and after surgery. Factors associated with changes in the bacterial count were further examined. Patients received systemic antimicrobials for an average of four days immediately before surgery. Results: Postoperative salivary bacterial counts were higher in older patients, who had erupting teeth and had longer surgical times. The average number of colonies before surgery was 10 4.53 CFU/mL; on the day after surgery, this number significantly decreased to 10 3.68 CFU/mL. The rate of reduction was especially high in infants without tooth eruption. The total number of bacterial colonies in saliva decreased after surgery, most likely because of the use of systemically administered antibiotics, and the rate of decrease was particularly high in infants without tooth eruptions. Conclusion: This study examined the preoperative and postoperative salivary bacterial counts in infants undergoing cardiac surgery. In the future, we would like to further examine bacterial flora and the effects of perioperative oral care. This study provides insights into the development of new strategies for preventing and treating surgical site infections and pneumonia in children.