The Correlation Between The Respiratory Aerobic Pathogen Colonization In The Oral Cavity And The Hospital-acquired Pneumonia In Elderly Patients:Clinical Sthdy

Objective: The purpose of this study was to investigate the effects of differentoral interventions to the incidence of the oropharygeal respiratory aerobic pathogenicbacterial colonization and the morbidity of hospital-acquired pneumonia(HAP) in thelong-term hospitalized elderly people.The other aim of this research was to study thehomology of oral aerobic pathogenic colonization bacteria and pathogens of HAP inthe long-term elderly inpatients on molecular level.Methods:62elderly patients (>65years)in our hospital were randomly dividedinto the treatment group(n=31) and the controll group(n=31). The treatment groupand the controll group were given compound chlorhexidine gargle and sterile salinerespectively to clean the oral cavity twice daily.Collecting the oral specimens(throatswab,supragingival plaque) of every objects at the first day(before intervention) and30th day (after intervention)after enrolled.Compared the incidence of theoropharygeal respiratory aerobic pathogenic bacterial colonization and the morbidityof HAP between the two groups. Sputum samples were obtained from HAPpatients.Repetitive element polymerase chain reaction(rep-PCR)was used todetermine the genetic relatedness of strains obtained from oral samples acquired atthe first day and sputum samples.Results:1.the effects of different oral interventions to the incidence of the oropharygealrespiratory aerobic pathogenic bacterial colonization and the morbidity ofhospital-acquired pneumonia(HAP): (1) The incidence of the pharygeal respiratory aerobic pathogenic bacterialcolonization in the treatment group after oral intervention(32.26%) was lower thanbefore (58.06%).And the incidence of the supragingival plaque colonization afteroral intervention(27.59%) was much lower than before (55.17%).The differenceswere all statistically significant(P<0.05).(2) The incidence of the pharygeal respiratory aerobic pathogenic bacterialcolonization in the controll group after oral intervention(32.26%) was lower thanbefore (54.84%).And the incidence of the supragingival plaque colonization afteroral intervention(28.57%) was lower than (53.57%).But the differences don`t havestatistically significance(P>0.05).(3) The morbidities of HAP between the treatment group and the controll groupwere10.20/1000hospitalizations and14.12/1000hospitalizations respectively.Thedifference was statistically significant(P<0.05).2. the homology of oral aerobic pathogenic colonization bacteria and pathogensof HAP on molecular level:(1)The rate of aerobic pathogenic colonization from pharyngeal was56.45%.The colonization rate of dental plaque was54.39%. Gram-negative bacilli accountedfor66.27%and Gram-positive cocci accounted for33.73%. Pseudomonasaeruginosa,Staphylococcus aureus and Acinetobacter baumannii occurredsignificantly more frequent among the oral colonization bacteria.(2)26strains among the36strains HAP pathogenic bacteria had100%similarityof rep-PCR patterns.Conclusions:(1) The oral intervention of using compound chlorhexidine gargle or sterilesaline daily both decrease the incidence of the oropharyngeal respiratory aerobicpathogenic bacterial colonization.But rinsing the mouth using compound chlorhexidine gargle for a long term could decrease the morbidity of HAP thansterile saline.(2)The rate of oral aerobic pathogenic colonization is highly in the long-termelderly inpatients，especially Gram-negative bacilli.(3)The oral bacteria colonization serves as an important reservoir for HAPpathogens.