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1.
CONTEXT: Central venous catheters impregnated with chlorhexidine and silver sulfadiazine have recently been introduced for the prevention of catheter-related infections. However, there remains some uncertainty regarding the efficacy of these catheters because of conflicting reports in the literature. OBJECTIVE: To evaluate the efficacy of chlorhexidine-silver sulfadiazine-impregnated central venous catheters in the prevention of catheter-related bloodstream infection. DATA SOURCES: Studies identified from a computerized search of the MEDLINE database from January 1966 to January 1998, reference lists of identified articles, and queries of principal investigators and the catheter manufacturer. STUDY SELECTION: Randomized trials comparing chlorhexidine-silver sulfadiazine-impregnated central venous catheters with nonimpregnated catheters were included. The outcomes assessed were catheter colonization and catheter-related bloodstream infection confirmed by catheter culture. DATA EXTRACTION: Twelve studies met the inclusion criteria for catheter colonization and included a total of 2611 catheters. Eleven studies with a total of 2603 catheters met the inclusion criteria for catheter-related bloodstream infection. Most patients in these studies were from groups considered to be at high risk for catheter-related infections. Summary statistics were calculated using Mantel-Haenszel methods under a fixed-effects model. DATA SYNTHESIS: The summary odds ratio for catheter colonization was 0.44 (95% confidence interval [CI], 0.36-0.54; P<.001), indicating a significant decrease in catheter colonization associated with impregnated catheters. The studies examining the outcome of primary interest, catheter-related bloodstream infection, had a summary odds ratio of 0.56 (95% CI, 0.37-0.84; P = .005). CONCLUSIONS: Central venous catheters impregnated with a combination of chlorhexidine and silver sulfadiazine appear to be effective in reducing the incidence of both catheter colonization and catheter-related bloodstream infection in patients at high risk for catheter-related infections.  相似文献   

2.
We evaluated the antithrombogenicity of 4F-catheters coated with the new antithrombogenic material fluorine-acryl- styrene-urethane-silicone (FASUS) graft-block copolymer by dissecting microscopic and scanning electron microscopic observations. These catheters were temporarily used for the infusa-A-port, which was prepared for the treatment of four patients with bladder cancer. Two heparin-coated catheters were also evaluated. All FASUS-coated catheters contained thrombi consisting of red thrombi and/or fibrin thrombi. Massive red thrombus was seen at the site of curvature of the catheters, 1 cm distal to the tip of the catheter. However, the portion 20 cm distal to the tip of the catheter had no red thrombus, but contained minimal fibrin thrombus or plasma protein. The heparin-coated catheters showed the same findings as the FASUS catheters. The FASUS-coated catheters were not superior in antithrombogenicity to the heparin-coated catheters. It was concluded that the FASUS-coated catheters used in this study seemed to have problems in regard to their preshaped curvature and the material used in catheter. These aspects need to be improved.  相似文献   

3.
TR Kohler  TR Kirkman 《Canadian Metallurgical Quarterly》1998,28(1):59-65; discussion 65-6
PURPOSE: Thrombosis associated with central venous catheters is a significant cause of device failure, morbidity, and loss of access sites. We hypothesized that central vein thrombosis is caused by catheter injury to the vein wall and that it can be reduced by stabilizing the catheter tip. To test these hypotheses, we studied central vein catheters in a porcine model. Test catheters had a silicone-encased stainless steel loop at the indwelling end that contacted the vein wall and stabilized the catheter tip in the center of the vessel. METHODS: Sealed silicon elastic (Silastic) catheters (3.2 mm outer diameter) with and without a stabilizing loop were inserted via the external jugular vein into the superior vena cava just above the right atrium. Animals were killed at 1, 2, 4, and 8 weeks, and the vena cava was inspected for the presence of thrombus and entrapment of the catheter tip. RESULTS: In control animals mural thrombus developed at the site of the catheter tip. This thrombus organized by invasion of macrophages and smooth muscle cells, eventually forming a lesion similar to intimal hyperplasia. Lesion cross-sectional area was significantly smaller in animals with loop catheters than in control animals at 2 weeks (1.2 +/- 1.3 vs 34.5 +/- 23.9 mm2; p = 0.05) and 4 weeks (2.8 +/- 0.3 vs 13.9 +/- 5.8 mm2; p < 0.05). By 8 weeks the vena cava was nearly occluded in most animals and the catheter tip was entrapped in this lesion in all cases. Test catheters eliminated the injury process for up to 8 weeks (p < 0.01, chi2 control vs loop catheter entrapment). Very little injury response was found where the loop contacted the vein wall, and the catheter tip was free of thrombus in all cases. CONCLUSIONS: Mural thrombosis at the tip of indwelling central catheters is caused by chronic mechanical venous wall injury. Vessel injury and the resulting thrombosis can be prevented by a catheter modification that stabilizes the tip. Such a catheter may significantly reduce catheter malfunction and morbidity associated with these devices.  相似文献   

4.
In a recent clinical trial, 248 triple-lumen catheters were removed from patients in an intensive care unit, and their tip and subcutaneous segments were cultured by both the sonication and roll plate methods; for 191 of these catheters, flush cultures of all three catheter lumens were also performed. Previously published quantitative endpoints were used to define significant catheter colonization. By using a composite index as a definition of colonization (any of the seven types of cultures meeting quantitative criteria), sonication of the subcutaneous segment was the most sensitive at detecting colonization (58%), followed by sonication of the catheter tip (53%). Sonication of both the subcutaneous and tip segments was 20% more sensitive than sonication of an adjacent catheter segment by the roll plate method (P < 0.05). The greater sensitivity of the sonication method could be attributed to its greater ability than the roll plate method to detect catheter lumen colonization (82 versus 57%, respectively; P = 0.01). A greater number of positive catheter segment cultures were found for colonized catheters from patients with associated bacteremia than for colonized catheters from patients without bacteremia (57 versus 37%; P = 0.004), making any culture method more likely to identify them. For catheters with significant colonization of only one site, the localization was as follows: 36.7% subcutaneous segment, 36.7% catheter lumen, and 26.6% tip segment. These findings suggest that the current practice of culturing a single segment of a central vascular catheter is inadequate and needs to be reexamined. They further suggest that initial colonization of the catheter lumen and tip segments may be more important than previously thought and may require a change in thinking of strategies designed to prevent catheter infection.  相似文献   

5.
OBJECTIVES: Determine whether systematic replacement of central venous catheters on a guide wire every 4 days leads to a lower rate of catheter infection. METHODS: We conducted a prospective randomized study comparing systematic catheter replacement with the standard procedure where one-way catheters are left in situ as needed. RESULTS: The study included 150 patients and 170 catheters. Catheter replacement on a guide wire was performed 169 times. The rate of infection was not significantly different between the group of patients with replacement (3.7 for 1000 catheter days) and the group with systematic replacement (5.4 for 1000 catheter days). No mechanical complications occurred during the replacement procedures on guide wires. CONCLUSION: We do not recommend systematically replacing catheters on a guide wire for the prevention of catheter infection. This procedure may however be indicated in case of suspected catheter infection as no mechanical of infectious complications occurred.  相似文献   

6.
Subcutaneous central venous infusion reservoirs (central venous catheters) are one of the primary devices for administration of intravenous chemotherapy. Usually these devices have few problems, and they provide dependable long term central venous access. Infection of these catheters is a significant problem that usually requires removal. When infection is suspected, it is often difficult to make this determination without actually removing the catheter. Thorough preoperative evaluation may help the surgeon decide which catheters are infected and should be removed. A total of 817 subcutaneous infusion reservoirs were placed at our institution from January 1, 1990 through November 1, 1994. During the same time period, 143 catheters were removed, 63 for suspected infection. The charts of these 63 patients were reviewed to determine to what extent available preoperative information could be used to predict which catheters were infected, thus avoiding unnecessary removal. Twenty-three preoperative parameters were assessed, including physical exam, body temperature, leukocyte count, platelet count, blood cultures from the catheter and peripheral blood, time from placement to removal, whether or not the catheter was functional, and whether it was currently in use. Forty catheters (65%) removed for suspected infection were infected, as demonstrated by a positive culture from the catheter or the wound. Staphylococcus was the most common microorganism. Physical exam (local erythema, tenderness, or swelling) correlated significantly with catheter infection (P = 0.0238). In contrast, blood culture data and the other clinical and laboratory parameters showed no significant association with catheter infection. We conclude that physical exam is the best indicator of catheter infection. Commonly used parameters such as fever, leukocytosis, and positive blood cultures are nonspecific, may not be due to catheter infection, and were not significant in our study. Removal and subsequent restoration of long term intravenous access is associated with significant morbidity and expense. Clinical decision making should not be based on isolated laboratory findings, but must be individualized in each patient with suspected catheter infection.  相似文献   

7.
Surface topography of used (in situ > 12 months) and unused CAPD catheters was studied by scanning electronmicroscopy (SEM) and confocal laser scanning microscopy (CLSM). Microbial biofilm was observed on all used catheters. Disruption and removal of the attached biofilm revealed extensive pitting of the catheter surface and scoring within the catheter pores. Similar, though less extensive, surface defects were present in unused catheters. Examination by CLSM, with software specific to the determination of surface topography, showed used catheters to have a surface microrugosity greater than that of unused catheters (p < 0.0005). Adherence studies with radiolabelled Staphylococcus epidermidis demonstrated increased adherence to used than to unused catheters (p < 0.0005) after 48 h. However, when catheters were pre-treated with spent dialysate there was a substantial reduction in bacterial adherence to either catheter and no significant difference in adherence to used and unused catheters. Surface microrugosity of CAPD catheters increases during use but is unlikely to be an important factor in bacterial adherence in vivo.  相似文献   

8.
BACKGROUND: Chronic ambulatory peritoneal dialysis (CAPD) is now an established technique for renal dialysis. Patients with renal failure cope poorly with major surgery and it is vital that the dialysis catheter tip is sited accurately in the pelvis if long-term catheter function is to be achieved. Laparoscopic placement of CAPD catheters may have potential advantages for renal patients by avoiding the morbidity of a laparotomy. METHODS: A retrospective audit was performed of all CAPD catheters inserted at the John Hunter Hospital over a 2-year period. Results of laparoscopically inserted catheters and those placed at laparotomy were compared. RESULTS: Sixty catheters were inserted, 30 laparoscopically and 30 at laparotomy. The mean operative time was 41 min in the laparoscopic patients and 57 min in the laparotomy patients (P = 0.0001). The mean total dose of narcotic administered postoperatively was significantly less in the laparoscopic group (5 mg vs 65 mg, P = 0.00002). There were three minor peri-operative complications in the laparoscopic group and seven peri-operative complications in the laparotomy group, three required reoperation and one resulted in the patient's death. There were no significant differences in the incidence of exit-site infection, catheter blockage, peritonitis, and overall catheter survival, although the laparoscopically placed catheters had been followed up for a shorter period (10 vs 16 months). CONCLUSIONS: This laparoscopic technique is safe and effective. Postoperative pain was less than for open placement. Laparoscopically placed catheters had a low incidence of peri-operative complications. Medium-term patency is similar to conventionally placed catheters. This procedure requires no additional equipment to that available for laparoscopic cholecystectomy and takes less time than the open operation.  相似文献   

9.
PURPOSE: To determine prospectively the feasibility, complications, and mid- and long-term advantages of peripheral insertion of central catheters in infants and children. MATERIALS AND METHODS: During a 15-month period between March 1995 and June 1996, a total of 285 catheter placement attempts were made to peripherally insert central catheters in 183 pediatric patients (89 boys, 94 girls). Phlebographic guidance was used, and the catheters were inserted below the elbow in 99% of cases. Catheter insertion was indicated for prolonged antibiotic therapy in 108 patients (158 catheter placement attempts), hematologic or oncologic care in 24 patients (40 attempts), total parenteral nutrition in 16 patients (46 attempts), and venous access for fluid or blood in 35 patients (41 attempts). The success rate and complications were recorded along with the indication, patient age, and duration of catheter placement. RESULTS: One hundred fifty-two of 158 (96%) catheter placement attempts were successful in outpatients (n = 108), 124 of 127 (98%) in hospitalized patients (n = 75), and 70 of 73 (96%) in patients aged less than 1 year. Infection and pericatheter venous thrombosis were the main complications and were seen in 17 of 276 (6%) and one of 276 (0.3%) catheter placement attempts, respectively. Catheter occlusion occurred in 23 of 276 (8%) catheter placement attempts. CONCLUSION: Peripheral insertion of central catheters was highly feasible in infants and children with this protocol. Such catheters were well tolerated in the pediatric population with a low frequency of complications.  相似文献   

10.
PURPOSE: To determine what interaction and effect different cholesterol gallstone solvents have on catheters used for gallstone chemolysis. MATERIALS AND METHODS: Five types of catheters used for biliary procedures were chosen: polyethylene, Percuflex, silicon, Silitek, and polyurethane. The solvents chosen were methyl tert-butyl ether, ethyl propionate, isopropyl acetate, and N-propyl acetate. After incubation of the catheters in the solvents for 72 hours, they were air dried. Weight and area changes were determined for each catheter. Additionally, carbon-13 nuclear magnetic resonance (NMR) spectroscopy was performed for analysis of composition changes. RESULTS: Three catheters--silicone, Silitek, and polyurethane--showed changes in their physical characteristics that would make them less desirable for stone chemolysis. The silicone catheter showed changes in elastic texture as well as marked weight reduction. The Silitek and polyurethane catheters had similar, but less dramatic changes. C-13 NMR analysis of collected solvents showed that commonly used plasticizers were leached out of some catheters. CONCLUSION: These results suggest that all catheters are not suitable for use with all solvents. The choice of catheter should be made based on the solvent in use. The polyethylene catheter performed best under the conditions and endpoints used in this study.  相似文献   

11.
The purpose of this study was to assess the feasibility of a newly developed field inhomogeneity catheter for interventional MRI in vivo. Different prototypes of a field inhomogeneity catheter (pigtail and multipurpose configuration, balloon catheters) were investigated in pigs. The catheters were introduced in Seldinger technique via the femoral vessels over a guidewire on an interventional MR system (Philips Gyroscan NT combined with a C-arm fluoroscopy unit [Philips BV 212]). Catheters were placed in veins and arteries. The catheter position was controlled by a fast gradient-echo sequence (turbo field echo [TFE]). Catheters were introduced over a guidewire without complications in all cases. Using the field inhomogeneity concept, catheters were easily visualized in the inferior vena cava and the aorta by the fast gradient-echo technique on MR in all cases. Although aortic branches were successful cannulated, the catheters were not well displayed by the TFE technique due to the complex and tortuous anatomy. All animals survived the experiments without complications. MR-guided visualization of a field inhomogeneity catheter is a simple concept that can be realized on each MR scanner and may allow intravascular MR-guided interventions in future.  相似文献   

12.
Intravascular ultrasound imaging (IVUS) is a new method that permits in vivo visualization of central venous catheters with hitherto unknown image resolution. It provides information not only about thrombus formation, but also about catheter movement, catheter malposition, and vessel wall injuries. In the present investigation the method was applied to evaluate the frequency of thrombus formation on double-lumen hemodialysis catheters and its significance for catheter malfunction. In 14 patients who had a double-lumen hemodialysis catheter for temporary or long-term vascular access, IVUS of the catheter and the mediastinal vein stems was performed. Mean indwelling duration at the time of the ultrasound investigation was 101 days (range. 3 to 730 days; median, 58 days). Four patients had catheter-related thrombotic complications: IVUS failed to detect an intracatheter thrombus in one case; a catheter thrombus and superior vena cava stenosis were found in a catheter with normal function in one case; in one case with catheter malfunction, a combined catheter-mural thrombus was found; and in the remaining case, a catheter thrombus and a mural superior vena cava thrombus were found in a patient with normal catheter function and pulmonary emboli. Thus, two of 12 patients with well-functioning catheters (16%) had thrombotic complications demonstrated by IVUS, and one of two patients with catheter malfunction had thrombus identified by IVUS. It is concluded that thrombus formation is less likely in patients without signs of catheter malfunction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

13.
The aim of this prospective study was to compare differential blood cultures and quantitative catheter tip cultures for the diagnosis of catheter-related sepsis. Over a period of 2 years, 283 central venous catheters were inserted in 190 adult patients. Catheters were removed when they were no longer needed or when infection was suspected. Immediately before removal of the central venous catheters, blood cultures were performed, with blood drawn simultaneously from the catheter and the peripheral vein. After removal, quantitative catheter culture was performed according to the Brun-Buisson modified Cleri technique. Fifty-five quantitative catheter cultures were positive. They were classified as contaminated (n = 18), colonized (n = 23), or infected (n = 14). Differential blood cultures correctly identified 13 infections. With a catheter/peripheral cfu ratio of 8, differential blood cultures had a sensitivity of 92.8% and a specificity of 98.8%. When the catheters were removed because of suspected infection, differential blood cultures had a sensitivity of 92.8% and a specificity of 100%. Differential blood culture, a technique that does not necessitate catheter removal, seems effective in the diagnosis of catheter-related sepsis in patients in the intensive care unit.  相似文献   

14.
OBJECTIVES: The purpose of this study was to evaluate a new technique for sterilizing nonlumen electrophysiology catheters that uses hydrogen peroxide gas plasma. BACKGROUND: The reuse of electrophysiology catheters may potentially result in a significant cost savings. While ethylene oxide sterilization appears to be safe and effective from a clinical standpoint, toxic ethylene oxide residuals, which exceed Food and Drug Administration standards, have been reported. METHODS: Ten nonlumen electrophysiology catheters were extensively evaluated. Each catheter was used five times and resterilized after each use with hydrogen peroxide gas plasma. Tests for sterility, mechanical and electrical integrity, chemical residuals and standard and electron microscopic inspection were performed. RESULTS: Loss of electrical integrity or mechanical integrity was not observed in any catheter. No evidence of microbial contamination was found. Surface integrity was preserved except for one ablation catheter that exhibited fraying of the insulation at the insulation-electrode interface. Surface inspection using standard magnification and electron microscopy revealed no significant change in surface characteristics associated with the sterilization process. Hydrogen peroxide was the only chemical residual noted, with an average concentration of 0.22% by weight, which is within accepted American Association for the Advancement of Medical Instrumentation limits. The cost for a standard electrophysiology catheter ranges from $200 to $800, and one sterilization cycle costs $10. If electrophysiology catheters are used five times, resterilization could potentially result in a savings of $2,000 per catheter, or $9,000 for five ablation procedures. CONCLUSIONS: Hydrogen peroxide gas plasma sterilization may provide a cost-effective means of sterilizing nonlumen electrophysiology catheters without the problem of potentially harmful chemical residuals. However, careful visual inspection of catheters, particularly at the insulation-electrode interface, is required if catheter reuse is performed.  相似文献   

15.
PURPOSE AND MATERIAL: A new family of catheters was developed to overcome the shortcomings of conventional catheters and to avoid the use of coaxial catheters in superselective angiography and embolization. The new catheter is nylon, 1.67 mm (JF) long, and has a rigid proximal part (to ensure torque control and pushability) and a long 2-step flexible tip (to follow arterial tortuosities). It has a hydrophilic coating, and a long-lasting shape memory. This new catheter type was compared experimentally with conventional catheters. RESULTS: Clear advantages were found with the new catheters in pushability and trackability as they, more often than conventional catheters, permitted us to reach the periphery of an artery. Departmental experience with the new catheters currently amounts to over 500 arterial procedures. CONCLUSION: The new catheters could frequently replace coaxial catheters, which would contribute towards reducing the costs of intravascular procedures.  相似文献   

16.
Tunneled intraspinal catheters and catheter-pump systems are increasingly common treatments for severe chronic pain, but these long-term catheters have caused meningitis, epidural abscesses, and other serious infections. At a cancer referral center, 81 catheters were placed in 72 patients over a 7-year period. There were seven catheter-associated infections: two were meningeal (one was accompanied by an epidural abscess and one by a pocket infection and bacteremia), four were associated with a pocket, and one was associated with a tunnel. The infection rate was 0.77 per 1,000 catheter-days. Pathogenic organisms that were isolated were primarily normal skin flora. By multivariate Cox analysis, the only factor significantly associated with catheter infection was prolonged catheter placement surgery, i.e., a procedure lasting at least 100 minutes (RR, 8.8; 95% CI, 1.6-50). Three patients were cured by removal of the catheter and treatment with antibiotics, and symptoms were satisfactorily suppressed in four patients with antibiotics alone. Considering the severity of illness in catheter recipients, the infection rate was relatively low. Removal of the catheter does not appear mandatory when the goal is suppression of infection-related symptoms, especially when the infection has not spread to the CNS, the infecting organism has an intrinsically low virulence, and the infected patient is terminally ill.  相似文献   

17.
The objective of this study was to evaluate the safety of reusing ablation catheters with temperature control, which has not previously been reported. A review of previously conducted studies on the feasibility of reusing electrode catheters is also presented. From September 1994 to December 1997, 74 deflectable ablation catheters with temperature control (Cordis-Websters and Osypkas) were used during mean 7.6 +/- 8.0 ablation sessions. The catheter tests included visual inspection for surface defects using a magnification glass, impedance measurements, evaluation of the catheter deflection capability, and the integrity of the thermistor and thermocouple. The catheters were sterilized by Sterrad after each use. A total of 41 catheters were rejected after an average 9.1 +/- 8.8 uses (range 1-31). The main reasons for rejection were inaccurate temperature measurements by the thermistor or thermocouple (19%), breakage of or defect in the internal pulling wire (12%), loss or disturbance of electrogram (9%), and loss of deflection capability (8%). The reuse of the catheters has not resulted in any major catheter failures or any major adverse clinical complications. There were no local or systemic infections. It can be concluded that these types of ablation catheters will sustain repeated uses and resterilizations without untoward harm to the patient provided that a thorough validation protocol and guidelines for quality control and rejection of catheters are used. There seems to be no rational for setting a limit for the number of reuses, since most failures occurred at any time of reuse.  相似文献   

18.
PURPOSE: To determine in-line pressures generated in small-bore central venous catheters during power injection of computed tomographic (CT) contrast media. MATERIALS AND METHODS: Five 3.0-7.0-F central venous catheters for pediatric patients were tested at full and half lengths in vitro. In-line pressures were measured during power injection of three contrast media. Rates of injection were increased in steps from 0.1 to 5.0 mL/sec or until a peak pressure of 100 psi (700 kPa) was achieved. The maximum tolerated flow rate was determined with reference to the manufacturer's suggested operating pressure limit for each catheter. RESULTS: At full length, the maximum tolerated flow rates were as follows: 2-3 mL/sec for the large lumen and 1-1.4 mL/sec for the small lumen of the 7.0-F double-lumen catheter; 0.2-0.4 and 0.8-1.2 mL/sec for the 3.0- and 4.0-F peripherally inserted central catheters, respectively; 0.7-1.2 mL/sec for the 6.6-F catheter; and only 0.2 mL/sec for the 4.2-F catheter, which ruptured during testing at higher flow rates. CONCLUSION: Flow rates were documented at which certain small-bore central venous catheters should tolerate power injection of CT contrast media with peak pressures remaining below the manufacturer's recommended operating pressure limits. These data may serve as a guide for clinical use.  相似文献   

19.
A laparoscopic technique was used to rescue dysfunctional Tenckhoff catheters in five continuous ambulatory peritoneal dialysis (CAPD) patients. This method proved to be effective in recovering the function of the catheters, whose malfunction was found to be due to catheter entrapment or endoluminal tamponing by the omentum. The videoscope-assisted laparoscopic technique provides access and allows identification and eradication of the specific etiology leading to catheter drainage failure. It also provides an alternative for treating patients with a dysfunctional Tenckhoff catheter. This method avoids the need to remove the original catheter or to reimplant a new catheter.  相似文献   

20.
A randomized controlled clinical trial was undertaken to evaluate the efficacy of antibiotic bonded lines in the reduction of central venous catheter infection. One hundred and seventy-six plain and bonded catheters were inserted into one hundred and ten patients in an intensive care unit, many of whom were admitted with evidence of sepsis. The catheters used in the study group, which had been pre-treated by the manufacturers with the cationic surfactant tridodecylmethylammonium chloride, were bonded with vancomycin 1 g made up in 10 ml of water immediately prior to insertion. The catheters used in the control group were neither pre-treated nor bonded with vancomycin. Eighty percent of control group catheters were infected compared with 62% of study catheters (p = 0.01). The most common organism isolated was coagulase negative staphylococcus. We conclude that antibiotic bonding can reduce central venous catheter infection even in a patient population with a high incidence of sepsis.  相似文献   

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