RESUMO
OBJECTIVES: Tube feeding might increase gastric burden of pathogenic bacteria and predispose patients to ventilator-associated pneumonia. We sought to determine whether a tube feeding formula acidified using potassium sorbate could reduce gastric burden of potentially pathogenic bacteria. DESIGN: Prospective, randomized, double-blind trial. SETTING: RML Specialty Hospital, a facility with expertise in weaning patients from prolonged mechanical ventilation. PATIENTS: Thirty patients recovering from prolonged mechanical ventilation. INTERVENTION: Patients were randomized to receive either a standard tube feeding formula (n=14) or a formula acidified using potassium sorbate to a pH of 4.25 (n=16). MEASUREMENTS AND RESULTS: Weekly quantitative cultures of gastric aspirates. The number of colony-forming units (CFUs) per patient was higher in the control than in the treatment group (53%+/-11% vs 9%+/-3.4%, threshold of >or=100,000 CFU/mL fluid, P=.003). The number of organisms isolated in each patient per week was higher among patients receiving standard tube feeding formula than among patients receiving acidified formula (0.91 +/- 0.20 vs 0.13 +/- 0.05 organisms per patient per week, threshold of >or=100,000 CFU/mL fluid, P=.0014). There was no difference in the incidence of gastrointestinal bleeding or ventilator-associated pneumonia between study groups. CONCLUSION: Tube feeding formula acidified using potassium sorbate was well tolerated and reduced gastric bacterial burden in patients recovering from prolonged mechanical ventilation.
