Methods
We retrospectively reviewed the medical records of tracheotomised children who were followed between 1 July 2012 and 31 May 2019 at Medipol University, Division of Pediatric Pulmonology. Children with tracheostomy and persistent bacterial colonization who were started on nebulized antibiotic therapy after a lower respiratory tract infection were included to the study. Demographic findings, comorbidities, indications for tracheostomy, age at tracheostomy, duration of tracheostomy were recorded. The number of oral antibiotic treatment, the number of hospitalizations, and the length of stay at the intensive care unit and the bacterial load (determined as the number of colony count per ml) were recorded from one year before and for 12 months after initiating nebulized antibiotic treatment. Antimicrobial resistance one year before and during the nebulized antibiotic treatment were obtained from patients’ medical records.
Following systemic antibiotic treatment for lower respiratory infections, patients with persistent bacterial colonization were started on nebulized antibiotics (gentamycin or colomycin) via inhalation through tracheostomy by a jet nebulizer according to the antimicrobial resistance results of tracheal aspirate cultures (gentamycin; 20 mg for children aged <2 years, 40 mg for children aged 2-8 years, and 80 mg for children aged >8 years old twice daily; colomycin; one million IU twice daily). Lower respiratory tract infections were defined as infections with lower airway symptoms (eg, need for intensified ventilator settings, increased oxygen supplementation, tachypnea, increased airway secretions)12.
Tracheal aspirate cultures were routinely obtained every three months during clinical visits and in the presence of signs of respiratory infections. Persistent colonization was defined as the isolation of the same bacteria in three or more consecutive tracheal aspirate cultures (at least one month apart) in the last year based on studies in the literature13,14. Nebulized antibiotic treatment was continued until the patients’ respiratory symptoms improved and the colony count decreased to 105 CFU/ml or lower in tracheal aspirate, which is the threshold value for the definition of infection15,16 .
Effect of current age, age at the time of tracheostomy and the duration of tracheostomy on the number of oral antibiotic treatment, hospitalizations, and the length of stay at the intensive care unit were evaluated. Kidney function tests were recorded to monitor the adverse effects of nebulized antibiotics.