Difference in efficacy between antibiotic lock technique and intramuscular injec- tion for the treatment central venous catheter-related infection in rabbit model / 中国感染控制杂志

Objective To compare the efficacy of antibiotic lock technique (ALT)and systemic medication on the treatment of central venous catheter-related infection(CRI).Methods Catheters which had been formed bacterial biofilm in vitro were implanted into the central venous of rabbits,and rabbits were randomly divided into two groups,catheter group received the injection of mixture of antibiotics and heparin,systemic group received intra-muscular injection of antibiotics and intraductal injection of heparin solution.Medicine was given continuously for 10 days,catheter blood and peripheral venous blood were taken every day before replacing the medicine,bacterial colo-ny counts were detected.All rabbits stopped using antibiotics on day 11,then removed catheters after a 5-day ob-servation of catheterization.Before extubation,the catheter blood and peripheral blood were collected to perform bacterial colony counting and antimicrobial susceptibility testing,and removed catheters were performed catheter tip bacterial culture and observation of biofilm.Results During the medication period,the average bacterial counts of catheter blood in catheter group at different time were all lower than systemic group,difference was statistically sig-nificant(all P < 0.05);from the 4th day,the catheter group gradually appeared positive specimens of peripheral blood culture(a total of 6 cases),and systemic group appeared positive specimens on the second day(a total of 31 ca-ses).During medicine withdrawal period,bacterial counts of catheter blood in two groups on the day of extubation were both higher than those on the day of medicine withdrawal,differences were both statistically significant(both P<0.05).On the day of medicine withdrawl,2 cases in catheter group and 8 cases in systemic group were isolated bacteria from peripheral blood;there was no new positive specimens in catheter group on the day of extubation,but there was 1 new positive specimen in systemic group.Catheter tip bacterial count in systemic group was higher than catheter group ([8.02±0.05]log10 CFU/mL vs [3.12±0.14]log10 CFU/mL,t =26.82,P <0.05).33.33% of specimens in catheter group could be observed scattered biofilm,while all specimens of systemtic group were cov-ered by biofilm.Bacterial culture and antimicrobial susceptibility testing of catheter blood and peripheral blood be-fore extubation revealed that diameter of the zone of inhibition in catheter group ranged 19-20 mm,in systemic group ranged 15 - 16 mm,bacteria from two groups were all sensitive to commonly used antimicrobial agents. Conclusion In the treatment of central venous CRI,the effect of ALT on local clearance of bacteria is better than that of systemic administration,and it can significantly reduce systemic infection.However,if bacterial biofilm in the catheter is not completely cleared,infection can still relapse after medicine withdrawal.Therefore,accurate dos-age and medication time is worthy of further quantitative study.

Difference in efficacy between antibiotic lock technique and intramuscular injec- tion for the treatment central venous catheter-related infection in rabbit model / 中国感染控制杂志

Objective To compare the efficacy of antibiotic lock technique (ALT)and systemic medication on the treatment of central venous catheter-related infection(CRI).Methods Catheters which had been formed bacterial biofilm in vitro were implanted into the central venous of rabbits,and rabbits were randomly divided into two groups,catheter group received the injection of mixture of antibiotics and heparin,systemic group received intra-muscular injection of antibiotics and intraductal injection of heparin solution.Medicine was given continuously for 10 days,catheter blood and peripheral venous blood were taken every day before replacing the medicine,bacterial colo-ny counts were detected.All rabbits stopped using antibiotics on day 11,then removed catheters after a 5-day ob-servation of catheterization.Before extubation,the catheter blood and peripheral blood were collected to perform bacterial colony counting and antimicrobial susceptibility testing,and removed catheters were performed catheter tip bacterial culture and observation of biofilm.Results During the medication period,the average bacterial counts of catheter blood in catheter group at different time were all lower than systemic group,difference was statistically sig-nificant(all P < 0.05);from the 4th day,the catheter group gradually appeared positive specimens of peripheral blood culture(a total of 6 cases),and systemic group appeared positive specimens on the second day(a total of 31 ca-ses).During medicine withdrawal period,bacterial counts of catheter blood in two groups on the day of extubation were both higher than those on the day of medicine withdrawal,differences were both statistically significant(both P<0.05).On the day of medicine withdrawl,2 cases in catheter group and 8 cases in systemic group were isolated bacteria from peripheral blood;there was no new positive specimens in catheter group on the day of extubation,but there was 1 new positive specimen in systemic group.Catheter tip bacterial count in systemic group was higher than catheter group ([8.02±0.05]log10 CFU/mL vs [3.12±0.14]log10 CFU/mL,t =26.82,P <0.05).33.33% of specimens in catheter group could be observed scattered biofilm,while all specimens of systemtic group were cov-ered by biofilm.Bacterial culture and antimicrobial susceptibility testing of catheter blood and peripheral blood be-fore extubation revealed that diameter of the zone of inhibition in catheter group ranged 19-20 mm,in systemic group ranged 15 - 16 mm,bacteria from two groups were all sensitive to commonly used antimicrobial agents. Conclusion In the treatment of central venous CRI,the effect of ALT on local clearance of bacteria is better than that of systemic administration,and it can significantly reduce systemic infection.However,if bacterial biofilm in the catheter is not completely cleared,infection can still relapse after medicine withdrawal.Therefore,accurate dos-age and medication time is worthy of further quantitative study.

In vitro Evaluation of Antibiotic Lock Technique for the Treatment of Candida albicans, C. glabrata, and C. tropicalis Biofilms

Candidaemia associated with intravascular catheter-associated infections is of great concern due to the resulting high morbidity and mortality. The antibiotic lock technique (ALT) was previously introduced to treat catheter-associated bacterial infections without removal of catheter. So far, the efficacy of ALT against Candida infections has not been rigorously evaluated. We investigated in vitro activity of ALT against Candida biofilms formed by C. albicans, C. glabrata, and C. tropicalis using five antifungal agents (caspofungin, amphotericin B, itraconazole, fluconazole, and voriconazole). The effectiveness of antifungal treatment was assayed by monitoring viable cell counts after exposure to 1 mg/mL solutions of each antibiotic. Fluconazole, itraconazole, and voriconazole eliminated detectable viability in the biofilms of all Candida species within 7, 10, and 14 days, respectively, while caspofungin and amphotericin B did not completely kill fungi in C. albicans and C. glabrata biofilms within 14 days. For C. tropicalis biofilm, caspofungin lock achieved eradication more rapidly than amphotericin B and three azoles. Our study suggests that azoles may be useful ALT agents in the treatment of catheter-related candidemia.

Catheter-related Sepsis: Clinical and Etiologic Analysis / 中华医院感染学杂志

OBJECTIVE To investigate the clinical and etiologic characteristics and treatment of central venous catheter-related(sepsis).METHODS Forty cases of patients with central venous catheter-related sepsis and their clinical manifestation,etiologic profiles and outcome of treatment were retrospectively analyzed.RESULTS Forty six strains were isolated including 23 strains of Gram-positive cocci,19 of Gram-negative bacilli and 4 of fungi.The most frequent(isolates) were Staphylococcus epidermidis.CONCLUSIONS The most common organism causing CRS is S.epidermidis;the key preventive measure is to avoid inner and outer pollution of catheter;antibiotic lock-technique can be taken for the treatment of uncertain CRS.If it is no effect after 24-48 hours,it is necessary to remove venous catheter promptly.

Treatment of Catheter-related Bacteremia with an Antibiotic Lock Protocol in Hemodilaysis Patients / 대한신장학회잡지

BACKGROUND: Catheter-related bacteremia is a frequent complication among hemodialysis patients using a tunneled cuffed catheter. The standard therapy of catheter-related bacteremia involves both systemic antibiotics and catheter replacement. This study was performed to evaluate the effect of antibiotic lock therapy in conjugation with systemic antibiotics without catheter removal on catheter-related bacteremia. METHODS: Thirty six chronic hemodialysis patients with tunneled cuffed catheter were monitored for infection between July 2001 and July 2005. We analyzed the efficacy of antibiotic lock protocol compared with systemic antibiotics alone. RESULTS: Twenty-nine episodes of catheter-related bacteremia occurred in 27 patients during the study periods. The incidence of catheter-related bacteremia was 1.5 episodes/1000 catheter-days. A single gram-positive coccus grew in the 16 cases (55.2 %), and gram-negative organisms grew in the 69 cases (31.0%). Sixteen of 18 patients (88.9%) treated with antibiotic lock protocol had successful catheter salvage versus only 6 of the 11 patients (54.5%) treated with systemic antibiotics alone (p=0.05). Three patients with Burkholderia pickettii and a patient with Acinetobactor calcoaceticus-baumannii complex were treated with antibiotic lock protocol with systemic ciprofloxacin and imipenem, respectively. CONCLUSION: This study suggests that antibiotic lock protocol in eradicating catheter-related bacteremia is effective treatment without requiring catheter replacement.

Prevention of Uncuffed Hemodialysis Catheter-Related Bacteremia (CRB) Using Antibiotic Lock Technique (ALT): A Randomized Controlled Trial / 대한신장학회잡지

BACKGROUND: Because of the rate of infection, NKF-K/DOQI guidelines recommended that uncuffed catheter (UC) should be used for no longer than 3 weeks. However, from data of the Dialysis Outcomes and Practice Patterns Study (DOPPS), it was recognized that 48% of new HD patients in US and 75 % in Europe use UC as temporary access. ALT has been recommended as a prevention of CRB in these patients. We prospectively evaluated the efficacy of catheter-restricted filling with Antibiotic Lock Solution in preventing CRB. METHODS: One hundred twenty new hemodialysis patients requiring temporary catheter while waiting for placement and maturation of an arteriovenous fistula were enrolled. Patients were excluded if they had clinical or microbiological evidence of infection or already received antibiotics. Patients with uncuffed, right internal jugular vein catheter were randomly assigned to receive either antibiotic-heparin lock solution (cefazolin 10 mg/mL, gentamicin 5 mg/ mL, heparin 1, 000 unit/mL) or heparin lock solution (heparin 1, 000 unit/mL) as a catheter lock solution during interdialytic period. The end point of the trial was CRB. RESULTS: CRB developed in seven (11.7%) patients receiving heparin lock solution (S. aureus 2, S. epidermidis 5) whereas one patient receiving ALT had S. aureus bacteremia. CRB rates per 1, 000 catheter-days were 0.44 in the ALT group versus 3.12 in the heparin lock solution group (p=0.031). Kaplan-Meier analysis also showed CRB-free catheter survival is longer in ALT group. CONCLUSION: These results showed that ALT could be an effective strategy for the reduction of CRB rate in hemodialysis patients with UC.

Indications and contra-indications of antibiotic lock technique in central venous catheter / 肠外与肠内营养

Objectives:To study indications and contra indications of antibiotic lock technique in central venous catheter. Methods:Fifty patients with sepsis during use of central venous catheter were studied prospectively.The drug of ceftazidine(0.5 g) was instilled into the central line as a transient “lock”, together with mixed solution(5 ml) of normal saline and heparin sodium. Results:Twenty nine cases were proved to be catheter related sepsis.5 cases were treated by removal of infected catheter.Twenty four cases were treated by antibiotic lock technique.Out of 24,only 13 cases wee successful. Conclusions:Indications of antibiotic lock technique are as follows:① transient use when looking for source of infection, ② in patients with late stage tumor, ③inpatients with steady state of illness and ④patients receiving home parenteral nutrition.The contra indications include:①inpatients in unsteady state of illness,②for short term transfusion or parenteral nutrition, ③patients with compromised immune responsiveness,and ④with deteriorated state of an illness or the infections not controlled.