Effect of Improved Oral Hygiene to Prevent Pneumonia in Hospitalized Patients

Recent studies have found that poor oral hygiene may foster the colonization of the oropharynx by potential respiratory pathogens in mechanically-ventilated (MV), intensive care unit (ICU) patients. Thus, improvements in oral hygiene in MV-ICU patients may prevent ventilator-associated pneumonia (VAP). The specific aims of this investigation are: 1) to organize the necessary infrastructure to develop and perform a pilot clinical trial to evaluate alternative oral hygiene procedures to prevent VAP; 2) to use this organization to perform a pilot clinical trial to determine if the use of oral topical chlorhexidine gluconate (CHX) will prevent dental plaque, oropharyngeal colonization by respiratory pathogens, and VAP in MV-ICU patients.

Recent studies have found that poor oral hygiene may foster the colonization of the oropharynx by potential respiratory pathogens in mechanically-ventilated (MV), intensive care unit (ICU) patients. Thus, improvements in oral hygiene in MV-ICU patients may prevent ventilator-associated pneumonia (VAP). The Specific Aims of this investigation are: 1) to organize the necessary infrastructure to develop and perform a pilot clinical trial to evaluate alternative oral hygiene procedures to prevent VAP; 2) to use this organization to perform a pilot clinical trial to determine if the use of oral topical chlorhexidine gluconate (CHX) will prevent dental plaque, oropharyngeal colonization by respiratory pathogens, and VAP in MV-ICU patients. This pilot longitudinal, double blind intervention study will consider the appropriate frequency of delivery of CHX to improve oral hygiene in MV-ICU patients. Preliminary data from these pilot studies will also allow accurate sample size calculations to be made for a large-scale multi-center clinical trial; and 3) to perform molecular epidemiological studies to identify and genetically type bacteria cultured from lower airway secretions of MV-ICU patients with or without VAP and compare them to isolates of the same species from their dental plaque. This pilot study will enable this multidisciplinary team of investigators to organize the infrastructure, patient recruitment and methodologic protocols, and data management and analysis procedures necessary to perform a multi-center, controlled clinical trial to assess the efficacy and generalizability of this intervention to improve oral hygiene in MV-ICU and prevent VAP.

Colonization of the Oral Cavity by Respiratory Pathogens (on Teeth/Denture/Buccal Mucosa) as Determined by Quantitative Cultures Expressed as Colony Forming Units (Cfu) Per ml (CFU/mL) of the Aerobic Cultivable Flora After 48 Hours

Samples were diluted and plated on sheep's blood agar (to isolate S. aureus), and MacConkey agar (for isolation of Gram-negative bacilli) and incubated for 72 hours at 37°C in 5% carbon dioxide. Plates were assessed for growth for the following target bacteria: S. aureus, P. aeruginosa, Acinetobacter species, and enteric organisms (Klebsiella pneumoniae, Serratia marcescens, Enterobacter species, Proteus mirabilis, Escherichia coli). Results of quantitative cultures were expressed as colony forming units (cfu) per ml of sample.

The CPIS score was calculated as follows: 1) Fever: 0 (36.5 to 38.4°C), 1 (38.5 to 39), 2 (<36.0 OR >39.0); 2) Leukocytosis: 0 (4000 to 11,000 white blood cells per mm3 of blood), 1 (11,000 to 17,000), 2 (>17,000); 3) New infiltrate: 0 = None, 1 = Patchy, 2 = Localized; 4) Secretions: 0 = None to minimal, 1 = moderate, 2 = large amount; and 5) PaO2/ FiO2: 0 = more than 330 and 2 = less than 330. Total scores for the subscales can range from 0-10, with lower scores indicating better outcome.

Inclusion Criteria: Patients included in this study will be those admitted to the trauma intensive care unit (TICU) of Erie County Medical Center (ECMC) hospital. All patients admitted to the TICU who are intubated and mechanically ventilated within 24-48 hours of admission will be eligible for study admission, with the exception of those demonstrating the following exclusion criteria: a) a witnessed aspiration (to eliminate patients with chemical pneumonitis); b) a confirmed diagnosis of post-obstructive pneumonia (e.g. advanced lung cancer); c) a known hypersensitivity to CHX; d) patients for whom consent can not be obtained; e) a diagnosed thrombocytopenia (platelet count less than 40 and/or a INR above 2) or other coagulopathy; f) a do not intubate order; g) children under the age of 18 years; h) Pregnant women; i) Legal incarceration; j) If transferred from another ICU; k) Those with oral mucositis; l) Those with immunosuppression (either-HIV or drug induced [e.g. organ transplant patients or those on long term steroid therapy]); m) Patients re-admitted to the TICU Comatose and intubated patients will be included since they represent patients at greatest risk for respiratory infection. Exclusion Criteria: Patients for whom consent can not be obtained.

Scannapieco FA, Yu J, Raghavendran K, Vacanti A, Owens SI, Wood K, Mylotte JM. A randomized trial of chlorhexidine gluconate on oral bacterial pathogens in mechanically ventilated patients. Crit Care. 2009;13(4):R117. doi: 10.1186/cc7967. Epub 2009 Jul 15.

Heo SM, Haase EM, Lesse AJ, Gill SR, Scannapieco FA. Genetic relationships between respiratory pathogens isolated from dental plaque and bronchoalveolar lavage fluid from patients in the intensive care unit undergoing mechanical ventilation. Clin Infect Dis. 2008 Dec 15;47(12):1562-70. doi: 10.1086/593193.