In order to identify the incidence of nosocomial pulmonary infection in surgical critical care patients in our hospital, we studied 800 patients discharged from surgical intensive care unit between May 1992 to Dec. 1994. One hundred and six episodes of pulmonary infection were found in 96 cases, in which 20 cases had been re-infected. The infection rate was 12.0%. The age of patients, APACHE- Ⅱ score and duration in ICU were closely related to the incidence of pulmonary infection. Tracheal intubation, tracheotomy and mechanical ventilation were the predisposing factors. The prevalent pathogens were pseudomonas aeruginosa, acinetobacter, staphylococcus aureus and candida albicans. 54.7% of cases were infected with more than one pathogens, and 36.8% of cases had fungal infection. The prevention and treatment are also discussed.
Objective To establish a rat model of chronic pulmonary infection by inoculating Pseudomonas aeruginosa to Sprague-Dawley(SD) rats.Metods Sixty SD rats were divided into 2 groups,ie.the P.aeruginosa group and the control group. Silicone tube precoated with P.aeruginosa was placed into the main bronchus. For the control group, sterile silicon tube was intubated. Results P ． aeruginosa was detected from lung tissue of rats in infected groups.Bacterial number was higher than 103cfu ／ g 28 days after inoculation.The pathological study showed fibrinous proliferation and granulomas formation in the lungs of infected rats 28 days after inoculation.Microscopy examination showed a inflammation predominantly with lymphocyte infiltration.In control group, no bacterial and pathological changes could be detected. Conclusions The animal model with P.aeruginosa chronic pulmonary infection can be established successfully by silicone tubes precoated with P.aeruginosa intubated into the main bronchus.
Objective To explore the clinical epidemiological characteristics of the lung infection after orthotopical liver transplantation. Methods The clinical data included infection morbidity, mortality, infectious times and relative factors, clinical manifestations, the bacterial strains and distributions of the pathogens, the bacterial resistances of the 53 liver transplantation recipients from 2003.3～2006.12 were summarized and analyzed retrospectively. Results Among 53 recipients, 33 developed lung infectious and 6 died .The mobidity was 62.3% and mortality was 18.2%, with a OR of 1.0. Lung infection predominantly occurred in the first month, especially in the first week after transplantation.There were many factors related to lung infections.Various pathogens, especially Klebsialla, Escherichia Coli and Staphylococus Hominis were isolated from sputum, airway suction drainages and throat swabs. Most of the G- bacteria were sensitive to aminoglycosides,β lactam and lactamase compounds and carbapenems while G+ bacteria were sensitive only to glycopeptides. All the bacteria were resistant to quinolones, β lactams of third and forth generation. Conclusions After liver transplantation, the morbidity and mortality of the lung infections are high.The infections develope at earlier stage, manifest nontypical clinical features.Many factors are revealed to be relevant to the lung infections,meanwhile, various drug-resistant pathogen strains are isolated.
抗生素的降阶梯治疗（de-escalation therapy）是近年来提出的用于治疗重症肺部感染的一个策略，在临床研究和实践中能够有效地提高重症感染治疗的成功率，降低病死率，同时降低住院时间和费用，是感染治疗策略的一大进展。本文就这一策略的概念演变和应用时机作一介绍
Objective To compare the systematic and lung pharmacokinetic parameters of moxifloxacin hydrochloride and explore a feasible tool to monitor drug concentration and evaluate therapeutic efficacy of respiratory fluoroquinolones. Methods Ten adult patients with community-acquired pneumonia or acute exacerbation of chronic bronchitis were enrolled.The subjects received a single dose of oral moxifloxacin hydrochloride 400 mg. Serum specimens were sampled at 0，1，2，3，4，8，24 h and sputum specimens were collected 0，1，2，4，8，20，24 h after administration，respectively.The serum and sputum concentrations of moxifloxacin hydrochloride were assayed by means of high-performance liquid chromatography. Standard pharmacokinetic parameters including peak concentrations(Cmax) and area under the concentration-time curve (AUC0-24 h) were assessed. Results Serum C(max) was（5.95±1.35）mg/L at 2 hours and serum AUC0-24 h was (58.72±8.11）mg·h-1·L-1 while sputum Cmax and AUC0-24 h were （16.18±6.47）mg/L at 3 hours and （138.04±78.29）mg·h-1·L-1 respectively，which were significantly higher than those in serum. Conclusion Oral administration of moxifloxacin hydrochloride to patients with respiratory infections results in rapid penetration into lung and maintain a one-fold drug concentration compared to blood concentration within 24 hours.Sputum drug concentration analysis demonstrates a superior pharmacokinetic profile of moxifloxacin in respiratory tract.
Objective To explore the role of CD4+CD25+ Treg cells in chronic pulmonary infection caused by Pseudomonas aeruginosa(PA).Methods Sixty SD rats were randomly divided into a PA group and a control group(n=30 in each group).Chronic lung infection model was established by implantation of silicone tube precoated with PA into the main bronchus.Twenty-eight days later Treg cells in peripheral blood were measured by fluorescence-activated cell sorting（FACS）.Levels of IL-10 and TGF-β in serum were assayed by ELISA.The expression of Foxp3 mRNA in spleen was measured by RT-PCR.Pathological changes of lung tissue were studed by HE staining.Results Treg/CD4+ T cells in the PA group were significantly more than those in the control group[（19.79±6.45）% vs （5.15±0.47）%，Plt;0.05].The levels of IL-10 and TGF-β were (231.52±54.48)pg/mL and （121.05±7.98）pg/mL in the PA group respectively，which were significantly higher than those in the control group[（35.43±23.56）pg/mL and （36.02±8.94）pg/mL].The expression of Foxp3 mRNA in the PA group was significantly higher compared with the control group(0.80±0.044 vs 0.25±0.054，Plt;0.05）.HE staining revealed that PA caused a intensive inflammatory reaction with lymphocytes infiltration.Conclusion CD4+CD25+ Treg cell is up-regulated and plays an important role in chronic lung infection caused by Pseudomonas aeruginosa.
Objective To explore the correlation between the levels of nitrite / nitrate( NO2 /NO3) in exhaled breath condensate ( EBC) and pulmonary infection in mechanically ventilated patients. Methods The clinical data from ventilated patients in critical care units of Peking University People’s Hospital from November 2006 to August 2007 were collected and analyzed. The patients’clinical pulmonary index score ( CPIS) were calculated. EBC of those patients were collected via endotracheal tube or tracheostomy cannula,and the concentrations of NO2 /NO3 were assayed. The level of NO2 /NO3 in different CPIS patients in 24 hours’ventilation, weaning proportion in 3 days and mortality in different NO2 /NO3 level patients were compared. The correlation of the CPIS and level of NO2 /NO3 were explored between survival and non-survival patients. Results A total of 76 patients were enroled. The NO2 /NO3 levels in patients of CPIS≤3, CPIS 3-6 and CPIS gt;6 in 24 hours of ventilation were ( 23. 31 ±5. 79) , ( 28. 72 ±9. 10) and ( 35. 42 ±12. 10) μmol / L respectively, with significantly differences between each other ( P lt; 0. 01) . The lower the patients’concentration of NO2 /NO3 was, the earlier the weaning and the lower the mortality were. The NO2 /NO3 levels on 4th and 7th day were detected in 24 survival patients and 23 non-survival patients. The difference of NO2 /NO3 levels between the survival patients and non-survival patients became significant on 7th day [ ( 29. 32 ±9. 52) μmol / L vs. ( 37. 22 ±12. 03) μmol / L, P lt; 0. 01] . Linear correlation analysis showed that the NO2 /NO3 level was positively correlated with CPIS ( r = 0. 76, P lt; 0. 01) . Conclusions The NO2 /NO3 level of EBC in ventilated patients is positively correlated to the severity of pulmonary infection, thus may be used as a new predictor for weaning and prognosis.
对临床上一个拟诊肺部感染的患者, 临床医生通常依据症状、白细胞总数和分类计数, 以及胸部影像学检查作出诊断, 以期尽早开始治疗, 此时抗生素的选择只能是经验性的, 等治疗后随访观察胸片上的浸润影有无吸收才能确定此浸润影是否为感染性的。换言之, 临床症状及影像学检查对于鉴别感染性和非感染性肺部疾病缺乏特异性, 而肺部感染的诊断多属于回顾性的。 目前, 有一些生物标志物用于帮助判断肺部浸润影为感染性或非感染性, 主要包括C 反应蛋白( C-reactive protein,CRP) 、降钙素原( procalcitonin, PCT) 和可溶性髓样细胞触发受体1( soluble triggering receptor expressed onmyeloid cells-1,sTREM-1) 等。