OBJECTIVETo investigate the clinical features of ventilator-associated pneumonia (VAP) caused by acinetobacter.

METHODSThe clinical manifestations of 45 cases with ventilator-associated pneumonia caused by acinetobacter between 1995 and 2002 were analyzed. Bacterial susceptibility of acinetobacter strains was determined by Kerby-Bauer method.

RESULTSThe mean age of the subjects was 58 +/- 13 years with 31 patients older than 60 years. All the patients had underlying diseases, most of which were respiratory diseases (37.8%), nervous system diseases (22.2%), and trauma (22.2%). Thirteen cases (28.9%) were mixed infections with other bacteria. The main manifestations were fever, purulent secretion, and solidification in the lung. X-ray revealed inflammatory infiltration in lower lobes of both sides. The mortality was 37.8%. The in vitro activity tests of 28 antibiotics against the acinetobacter strains showed that they were multiresistant. Polymysin B, imipenem, minocycline, ofloxacin, and amikacin were relatively active.

CONCLUSIONThe patients with VAP caused by acinetobacter usually had underlying diseases without unique features and high mortality, and the isolated strains were often mutiresistant. It is necessary to make early diagnosis, select the appropriate agents, and improve the disinfection of the breath loop in the ventilator.

Acinetobacter ; isolation & purification ; Acinetobacter Infections ; microbiology ; Aged ; Cross Infection ; etiology ; Drug Resistance, Bacterial ; Female ; Humans ; Male ; Middle Aged ; Pneumonia, Bacterial ; microbiology ; Ventilators, Mechanical ; microbiology

PURPOSE: To determine whether the practice of not routinely changing ventilator circuits in patients who require prolonged mechanical ventilation is associated with ventilator-associated pneumonia (VAP). METHODS: Patients were divided into two groups, ventilator circuits were routinely changed every 7 days for the control group (39) and every 14 days for the experimental group (40) over a period of 1 yr (April 1, 2009-March 31, 2010). Pediatric patients (age 17 yr or less) were not included. VAP was diagnosed by the criteria of the Centers of Disease Control and Prevention (CDC). Incidence of VAP and characteristics of infection were evaluated. RESULTS: In the experimental group, 2 episodes of pneumonia were observed in 40 patients and 1,322 ventilator days. The rate of VAP was 1.5 per 1,000 ventilator days. There was 1 episode of pneumonia in 39 patients and 481 ventilator days for the control group. The rate of VAP was 2.1 per 1,000 ventilator days. The difference between both groups was not significant (p=.695). CONCLUSION: Extending ventilator circuit change interval from 7 days to 14 days does not increase the risk for VAP.
Adult ; Aged ; Aged, 80 and over ; Female ; Humans ; Intensive Care Units ; Male ; Middle Aged ; Pneumonia, Ventilator-Associated/*epidemiology ; Risk Factors ; Sputum/microbiology ; Time Factors ; Ventilators, Mechanical

OBJECTIVEThe catheter-related infections caused by mechanical ventilation have become a intractable clinical problem, and it is related to the formation of bacterial biofilm (BF) on the surface of the implanted material. The majority of natural biofilms are formed by multiple bacterial species. However, there always only one or limited species were detected on tracheal tubes removed from intubated neonates by using traditional methods including bacterium culture and antigen detection. The aims of this study were to observe the bacterial communities diversity of BF on endotracheal tube (ETT), and discuss the difference between traditional bacterium culture methods and the use of molecular biology techniques on the basis of denatured gradient gel electrophoresis (DGGE), to provide new ideas for clinical prevention, diagnosis and treatment of bacterial infections.

METHODThirty-five ETTs were obtained from 26 neonates on mechanical ventilator (from October 2012 to March 2013) in Department of Neonatology of Children's Hospital. Among the patients, 18 were boys and 8 girls, and 19 patients were < 37 weeks gestational age and 7 patients ≥ 37 weeks. DGGE profiling of 16S rDNA gene amplicons was used to assess the diversity of the bacterial population by using the software of quantity one. TA Cloning Kit and sequencing were used to investigate the distribution of bacteria and common dominant bacteria in ETT-BF.

RESULTThe mean bands of 35 ETTs cases were 13.8 ± 5.4 from 16S rDNA PCR-DGGE, and the mean Shanon-Wiener indexes was 2.42 ± 0.38. The 16 ETTs were collected in different stages of diseases from the 7 patients. The indwelling days of 6/7 patients' ETTs increased, the Shanon-siener indexes were decreased. Among the 6 cases from different basic illnesses, and there were different Shanon-siener indexes. The result of molecular cloning and sequencing for 24 dominant bands showed that 35 cases (100%) contained Klebsiella SP·, 28 cases (80%) had Pseudomonas SP·, 27 cases (77%) had Streptococcus SP·, and 32 cases (91%) had Uncultured bacterium, while more than 2 bacterial species were found in 34 cases (97%). 28/35 (80%) Klebsiella SP· and 22/27(82%) Streptococcus SP· were accompanied by Pseudomonas SP·. There were 22 positive results of sputum culture from 26 newborns, including 10 strains (45%) of Klebsiella pneumoniae, 2 strains (9%) of Acinetobacter baumannii, Enterobacter cloacae and non-cultured bacterium in each patient (5%), but only one bacterium isolated from every sputum. Eight sputum samples had normal flora only, corresponding to the ETTs on which Klebsiella and other bacterial genuses were found.

CONCLUSIONThe diversity of microbiota in BF on ETT was confirmed. 16S rDNA PCR-DGGE could produce a more complete picture of bacterial community than traditional bacterium culture method. Klebsiella, Pseudomonas and Streptococcus were common dominant bacteria in ETT-BF, and there might be interactions among them in the formation of BF.

Bacteria ; classification ; genetics ; isolation & purification ; Biodiversity ; Biofilms ; Catheter-Related Infections ; microbiology ; DNA, Bacterial ; analysis ; genetics ; Denaturing Gradient Gel Electrophoresis ; Female ; Humans ; Infant, Newborn ; Intubation, Intratracheal ; adverse effects ; Klebsiella ; genetics ; isolation & purification ; Male ; Polymerase Chain Reaction ; Pseudomonas ; genetics ; isolation & purification ; RNA, Ribosomal, 16S ; genetics ; Respiration, Artificial ; adverse effects ; Sputum ; microbiology ; Streptococcus ; genetics ; isolation & purification ; Ventilators, Mechanical ; microbiology

OBJECTIVETo study the epidemiology of Acinetobacter baumannii infection in patients with ventilator-associated pneumonia (VAP).

METHODSProspective clinical study was carried out with 176 episodes of VAP with etiologic diagnosis being followed in two groups.

RESULTSTwenty-six episodes were caused by Acinetobacter baumannii and one hundred-fifty episodes were caused by "other" organisms. Using logistic regression analysis, the risk of VAP due to Acinetobacter baumannii was found to be high in patients with head trauma [odds ratio (OR) = 4.20, 95% confidence interva (CI): 2.72 to 6.48], surgery (OR = 2.88, 95% CI: 1.78 to 4.66), acute respiratory dispnea syndrome (OR = 2.81, 95% CI: 1.19 to 6.64), and large-volume pulmonary aspiration (OR = 6.71, 95% CI: 3.91 to 11.50).

CONCLUSIONSAcinetobacter baumannii pulmonary infection in incubated patients had an epidemiological pattern that different from "other" organisms. Patients with high risk identified in our study might mark the existence of cross-infection during airway manipulation.

Acinetobacter ; classification ; isolation & purification ; Acinetobacter Infections ; epidemiology ; etiology ; Aged ; Aged, 80 and over ; China ; epidemiology ; Cross Infection ; epidemiology ; etiology ; Female ; Follow-Up Studies ; Humans ; Logistic Models ; Male ; Middle Aged ; Pneumonia, Bacterial ; etiology ; microbiology ; Prospective Studies ; Respiration, Artificial ; adverse effects ; Respiratory Distress Syndrome, Adult ; complications ; Risk Factors ; Time Factors ; Ventilators, Mechanical ; adverse effects

PURPOSE: This study was conducted to identify endotracheal colonization and the incidence of ventilator-associated pneumonia related to the type of endotracheal suction system. METHODS: The participants in this study were ICU patients hospitalized between October 2009 to March 2010 who used ventilators for over 48 hr with closed (CSS, n=30) or open (OSS, n=32) suction systems. To standardize the pre-intervention suction system, a suctioning protocol was taught to the ICU nurses. Collected data were analyzed using chi2-test, Fisher's exact test, Wilcoxon rank sums test, Wilcoxon test, Log-rank test and Poisson regression. RESULTS: Endotracheal colonization was higher in OSS than CSS from day 1 to day 8 while using a ventilator and there was a significant difference between the two groups. The CSS reached 50% of endotracheal colonization by the 4th day, whereas for the OSS, it was the 2nd day (p=.04). The incidence of ventilator-associated pneumonia showed no significant difference. CONCLUSION: For patients with a high risk of pneumonia, CSS must be used to lower endotracheal colonization.
Adult ; Aged ; Aged, 80 and over ; Female ; Gram-Negative Bacteria/isolation & purification ; Gram-Positive Bacteria/isolation & purification ; Humans ; Incidence ; Intensive Care Units ; Intubation, Intratracheal/instrumentation/*methods ; Male ; Middle Aged ; Pneumonia, Ventilator-Associated/*epidemiology ; Risk ; Severity of Illness Index ; Time Factors ; Ventilators, Mechanical/*microbiology