Hospital-acquired urinary tract infections associated with the indwelling catheter

Indwelling urethral catheters are commonly used in patients admitted to acute care hospitals. Forty percent of nosocomial infections occur in the urinary tract, and greater than 80% of these infections are secondary to an indwelling urethral catheter. Fortunately, the majority of catheters are left indwelling for a short period of time. The duration of catheterization is directly related to the development of bacteriuria, nosocomial infection, and possible bacteremia with sepsis. A relatively low percentage of patients become infected during the first 3 to 5 days if sterile technique and proper maintenance of a closed system are performed. Bacteria may grow in the urine (planktonic) and ascend via the lumen, or bacteria in the biofilm around the outside of the catheter may infect the bladder. Most organisms are from the patient's intestinal flora, but exogenous sources on or near the patient may be involved. The major morbid events associated with the catheter are fever and the possible progression to bacteremia and sepsis. Early recognition of complications and arresting their progression, especially in the high-risk patient, are essential. Current research is directed at developing ways to reduce infection beyond the sterile closed system.     

1500例临时静脉留置导管透析的临床分析

目的探讨临时静脉内留置导管透析的血管选择、透析效果、并发症、影响因素及处理。方法静脉置管后观察导管血流量、留置时间、尿素清除指数（Kt／V）、再循环、血液流变学指标、并发症及其影响因素。结果颈内静脉、锁骨下静脉、股静脉是留置导管静脉常选静脉。1500例静脉留置导管总体使用良好，透析充分，Kt／V平均1．20±0．35；导管再循环率低为（10．5±2．5）％；留置导管常见的并发症依次为血流量不足、栓塞、感染、导管脱落等。大多数能通过调整导管位置、导管内溶栓及抗感染等处理改善；5例反复发生栓塞者血纤维蛋白原显著升高；导管尖端位于右心房者与上腔静脉者比较，前者具有更好的血流量、再循环率低[（285±50．5）ml／minVS（205±45．5）ml／mim（8±3．5）％VS（12±4．5）％，（P〈0．05）]；导管腔内高浓度肝素与低浓度肝素比较，前者导管留置时间明显延长（P〈0．05），检塞发生率减少（P〈0．05）。结论临时静脉内留置导管透析血流量充分，透析疗效确切。留置导管常见的并发症有血流量不足、栓塞、感染等，绝大多数能通过处理矫正。导管尖端位置、导管腔肝素浓度、血液粘度等对导管成活、血流量不足、栓塞有重要影响。     

Prophylactic efficacy of a new gentamicin-releasing urethral catheter in short-term catheterized rabbits

OBJECTIVE: To describe an indwelling urethral catheter coated with gentamicin sulphate on the inner and outer surface of the catheter, and to evaluate the efficacy and safety of this catheter in preventing catheter-associated infections in rabbits. Materials and methods Sixty rabbits were divided equally into control and experimental groups which were then subdivided equally according to the duration of catheterization (1, 3 and 5 days). Silicone-treated latex catheters were used in the control group and gentamicin-releasing catheters in the experimental group. Urine samples and surface swabs from the catheter were cultured for bacteriological assessment, and the catheter surface examined by scanning electron microscopy to structurally analyse the biofilms. RESULTS: The gentamicin-releasing catheter reduced the incidence of bacteriuria (defined as > or = 100 c.f.u./mL) after both 3 and 5 days of catheterization (eight and 10 rabbits, respectively, for the control catheter, vs two and four rabbits for the gentamicin-releasing catheter, P < 0.05). The surfaces of the gentamicin-releasing catheter were colonized less often than those of the control catheter after both 3 and 5 days (eight and 10, respectively, for the control, vs one and four for the gentamicin-releasing catheter, P < 0.05). Scanning electron microscopy showed the formation of bacterial biofilm throughout the 3-day and 5-day control catheters, but deterioration of the bacterial biofilm was visible on the surface of the gentamicin-releasing catheters. CONCLUSION: This new gentamicin-releasing catheter produced an antibacterial barrier which inhibited catheter-associated urinary tract infection with no toxicity for at least 5 days. These in vivo studies suggest that this new catheter may be useful for controlling infection, with systemic and local safety, in patients undergoing short-term indwelling urethral catheterization.     

What really affects the incidence of central venous catheter-related infections for short-term catheterization?

Central venous catheterization is one of the important sepsis reasons in surgical patients. In this randomized controlled study, the effect of the frequency and type of catheter site care, as well as age, coexisting malignancy or diabetes mellitus, total parenteral nutrition administration and antibiotics use, on central venous catheter infection was investigated. Seventy-two single-lumen polyurethane catheters were included. In group I (n: 33), a transparent occlusive dressing was applied to the insertion site and not removed for 7 days unless there were signs of local infection. In group II (n: 39), daily site care was done with povidone-iodine 10% solution and a new sterile gauze was applied. Chi-square, linear correlation and multiple regression tests were used for statistical analysis. Mean duration of catheters was 8 +/- 4 days. There was no catheter-related sepsis. Ten (13.9%) patients had positive catheter tip cultures of whom three had site infection as well. The incidence of site and tip infections were not significantly different in group I and II (p > 0.05). Site infection and age younger than 60 years significantly increased the rate of tip infection (p: 0.004 and p: 0.02 respectively). Total parenteral nutrition administration was associated with higher rate of tip infection (p: 0.06). Coexisting malignancy or diabetes mellitus, duration of catheter and antibiotics use did not have any significant effect on the rate of central venous catheter infections (p > 0.05). In conclusion, we observed that the frequency of insertion site care and the type of dressing applied to the site had no significant effect on the rate of CVC infection. Insertion site infection was the most significant factor increasing the incidence of catheter tip infection. The use of the CVC for total parenteral nutrition facilitated tip infection as well.     

Catheter-related sepsis in patients on intravenous nutrition: a prospective study of quantitative catheter cultures and guidewire changes for suspected sepsis

One hundred and ninety-five central venous catheters used for intravenous nutrition in 113 patients were studied prospectively. Catheter-related sepsis (CRS), defined by recovery of the same organism from the catheter tip and peripheral blood cultures, occurred with only 3.3 per cent of catheters or 2.3 per 1000 days of therapy. In contrast, CRS was suspected with 30 per cent of catheters and catheter contamination occurred in 37 per cent. Contamination was defined by a positive catheter tip culture without recovery of the same organism from the blood. CRS was present in 4 of 12 cases (33 per cent) with greater than 1000 colony forming units on the catheter tip but in only 2 of 54 (4 per cent) with fewer organisms. Thirty-eight cases suspected of having CRS were randomized to have catheter removal and later replacement, or replacement over a guidewire. There were no significant differences in the catheter contamination rate but there were significantly fewer problems of insertion in the guidewire group. However, transfer of Klebsiella sp., during the guidewire procedure, resulted in subsequent sepsis in one case. It is concluded that replacement of catheters over a guidewire is a safe and convenient way of establishing whether sepsis is catheter-related. Because organisms may be transferred, the procedure is not an appropriate treatment for catheter-related sepsis.     

Persistent Sciatic Artery Aneurysm: a Case Report

Central venous catheterization is one of the important sepsis reasons in surgical patients. In this randomized controlled study, the effect of the frequency and type of catheter site care, as well as age, coexisting malignancy or diabetes mellitus, total parenteral nutrition administration and antibiotics use, on central venous catheter infection was investigated.

Seventy-two single-lumen polyurethane catheters were included. In group I (n: 33), a transparent occlusive dressing was applied to the insertion site and not removed for 7 days unless there were signs of local infection. In group II (n: 39), daily site care was done with povidone-iodine 10% solution and a new sterile gauze was applied. Chi-square, linear correlation and multiple regression tests were used for statistical analysis.

Mean duration of catheters was 8 ±4 days. There was no catheter-related sepsis. Ten (13.9%) patients had positive catheter tip cultures of whom three had site infection as well. The incidence of site and tip infections were not significantly different in group I and II (p > 0.05). Site infection and age younger than 60 years significantly increased the rate of tip infection (p: 0.004 and p: 0.02 respectively). Total parenteral nutrition administration was associated with higher rate of tip infection (p: 0.06). Coexisting malignancy or diabetes mellitus, duration of catheter and antibiotics use did not have any significant effect on the rate of central venous catheter infections (p > 0.05).

In conclusion, we observed that the frequency of insertion site care and the type of dressing applied to the site had no significant effect on the rate of CVC infection. Insertion site infection was the most significant factor increasing the incidence of catheter tip infection. The use of the CVC for total parenteral nutrition facilitated tip infection as well.     

Infections associated with subclavian dialysis catheters: the key role of nurse training

Two hundred subclavian dialysis catheters were placed in 148 patients who kept them in place for a total of 2,798 days. Catheterization time ranged from 1 to 79 days with an average of 14.0 +/- 1.0 days per catheter and 18.9 +/- 1.0 days per patient. Twenty nine catheters were infected, 17 of which were the source of bacteremias due to Staphylococcus epidermidis in 13 cases and to Staphylococcus aureus in 4 cases. The incidence of sepsis was not significantly greater in diabetic patients, in patients with corticotherapy or in patients presenting an underlying systemic disease. On the contrary, the incidence was greater in hospitalized patients (15 bacteremias during 1,948 catheter days) than in ambulatory patients (2 bacteremias during 850 catheters-days) as well as during a period corresponding to a greater number of untrained nurses enrolled in the dialysis team. During this period, 6 sepsies occurred in 19 catheters (other periods: 7 sepsies/116 catheters, p less than 0.01). 6 of 28 nurses had less than 3 months of professional experience (other periods: 1 of 25, p less than 0.01). These data underline the key role of nurse training in the prevention of catheter-related infections.     

Prevention of dialysis catheter-related sepsis with a citrate-taurolidine-containing lock solution.

BACKGROUND: The use of haemodialysis catheters is complicated by catheter-related sepsis. Intraluminal colonization of the catheter with bacteria is important in the pathogenesis of catheter-related sepsis. The use of a catheter lock solution containing the antimicrobial taurolidine might prevent bacterial colonization, thereby reducing the incidence of catheter-related sepsis. METHODS: In a randomized prospective trial, patients receiving a dialysis catheter were included and catheters were locked with either heparin or a citrate-taurolidine-containing solution. Blood cultures drawn from the catheter lumen were routinely taken every 2 weeks and at time of removal of the catheter to detect bacterial colonization. Catheter-related sepsis and exit-site infections were registered for both groups. RESULTS: A total of 76 catheters were inserted in 58 patients. The incidence of catheter colonization progressed slowly over time with no differences between dialysis catheters filled with heparin or citrate-taurolidine-containing solution. The number of exit-site infections was also similar between both groups. In the heparin group, four cases of catheter-related sepsis occurred as opposed to no sepsis episodes in the patients with catheters locked with the citrate-taurolidine-containing solution (P<0.5). No side effects with the use of citrate-taurolidine catheter lock solution were noted. CONCLUSIONS: This study shows that catheter filling with a solution containing the antimicrobial taurolidine may significantly reduce the incidence of catheter-related sepsis. Taurolidine appears to be effective and safe and does not carry the risk for side effects that have been reported for other antimicrobial lock solutions containing gentamicin or high concentrations of citrate.     

Hickman catheter implantation in the treatment of acute leukemia

Between July 1980 and May 1981, 32 permanent indwelling Hickman catheters were implanted in 29 patients. Most of the catheters were placed for treatment of acute leukemia (25 patients) or lymphoma (two patients). Catheters were used for a total of 3,461 patient-days (mean, 108 days). Two patients had infections at the exit site, one seven and the other 11 days after implantation. Four patients had sepsis, but none of those infections appeared to be catheter related. Hickman catheters appear to provide ease of treatment in acute leukemia and are associated with patient satisfaction and an acceptable complication rate.     

Pathogenesis and predictability of central venous catheter sepsis

The purposes of this study were to analyze the causes and routes of infection of indwelling central venous catheters and to improve the diagnosis of catheter sepsis before the removal of the cannula. One hundred forty catheter tips were prospectively studies; also, cultures of 52 proximal segments of catheters, 44 swabs of the subcutaneous segment, 195 skin entry sites, 181 infusional fluids, 208 blood samples, and 106 infected distant sites were examined. The catheter sepsis rate was 7.6%, but this sepsis was primary in only 3.4%, because in 4.2% prior isolation of organisms from the wound, urine, throat, or sputum was possible, indicating that the catheter was not primarily responsible for the infection. Primary infection always disappears with removal of the cannula (with or without antibiotics), whereas the course of the secondary infection is related to the gravity of the infected foci and the involved microorganisms. Contamination of the infusional fluid, the skin entry site, and some distant foci carry a real risk of seeding the catheter (from 5.8% to 19.5%). The cultures of the skin entry sites, infusional fluids, distant foci, and the subcutaneous segment of the catheter did not prove useful in predicting the infection. Only the blood cultures were a reliable diagnostic tool: a positive blood culture meant colonization of the catheter tip in 44% of cases and sepsis in 36%. Although the potential colonization varied greatly for different microorganisms, the growth of microorganisms in the blood was a strong indication for removing the cannula.     

Predictive value of pericatheter skin cultures in detecting catheter-related infections in a medical-surgical intensive care unit

OBJECTIVE: To evaluate the predictive value of pericatheter skin cultures in detecting catheter-related infections in critically-ill patients. STUDY DESIGN: Prospective study. PATIENTS AND METHODS: Over a 5 months period (from August 1(st) 2001 to December 31 2001), 500 patients were hospitalised, and 108 central venous catheters were prospectively examined. For each catheter, blood cultures, pericatheter skin cultures and semiquantitative culture of the catheter tip were performed. RESULTS: The median duration of catheterization was 8 days (interquartile: 8 days). Catheter was removed because of suspected infection in 54 cases (50%). Systemic catheter-related infection was found in 12 cases (11%) and the responsible organism was a gram-negative rod in 11 cases (92%). The negative predictive values of pericatheter skin cultures in the diagnosis of catheter-related infections and in case of suspected catheter-related infection were 89 and 86%, respectively. CONCLUSION: These results indicate that the pericatheter skin cultures are not an effective procedure for the conservative diagnosis of catheter-related infections and that the skin-insertion wound is not the major source of catheter-contamination in our unit.     

Superiority of the femoral artery for monitoring: A prospective study

Continuous hemodynamic monitoring and ease of blood sampling are advantages of indwelling arterial catheters. The use and associated morbidity of arterial monitoring catheters were studied prospectively. Ninety-five percent of patients catheterized had multiple injuries, and almost 75 percent were 40 years of age or younger. Major and minor complication rates were similar with radial and femoral catheters, while the longevity of femoral catheters was almost twice that of radial catheters. Radial catheter-related sepsis did not occur when the duration of catheterization was less than 4 days. Tissue loss secondary to radial catheters can be minimized by immediate catheter removal upon appearance of ischemic changes. Our data support the preferential use of the femoral artery for long-term monitoring catheters in a younger patient population.     

Implanted Right Atrial Catheters for Continuous Infusion of Solutions into Dogs

Silastic catheters were fabricated and aseptically implanted through the skin into the jugular vein of 64 dogs with the intravascular tip located in the right atrium. Solutions were infused through the catheter at 2 to 2.5 mL/h by a portable pump worn by the dog. Following 9.2 Gy total body irradiation (TBI) and allogeneic bone marrow transplantation (BMT), succinyl acetone, an experimental chemotherapeutic agent, was infused into 34 dogs. Hematopoietic growth factors were infused into an additional 30 dogs, two of which had 9.2 Gy TBI and an autologous BMT, and four of which had 4.0 Gy TBI and no BMT. All dogs received continuous oral and parenteral antibiotics while the catheters were in place. All catheters functioned well until electively removed (n= 28) or until the dogs died or were euthanized (n= 36) at 12 to 68 days after implantation. Mean length of catheter function was 30.3 ± 1.5 (SEM) days. No catheters were dislodged and there was no evidence of catheter-related blood loss or sepsis. Semiquantitative cultures of 5 catheters were negative, but Staphylococcus epidermidis was isolated from 3 of 7 catheters cultured in broth. Six dogs had thrombosis adjacent to the intravascular catheter tip. The catheters were well tolerated and facilitated successful long-term infusion of solutions into dogs.     

Complications associated with peripheral or central routes for central venous cannulation

We undertook a review of studies comparing complications of centrally or peripherally inserted central venous catheters. Twelve studies were included. Catheter tip malpositioning (9.3% vs 3.4%, p = 0.0007), thrombophlebitis (78 vs 7.5 per 10,000 indwelling days, p = 0.0001) and catheter dysfunction (78 vs 14 per 10,000 indwelling days, p = 0.04) were more common with peripherally inserted catheters than with central catheter placement, respectively. There was no difference in infection rates. We found that the risks of tip malpositioning, thrombophlebitis and catheter dysfunction favour clinical use of centrally placed catheters instead of peripherally inserted central catheters, and that the two catheter types do not differ with respect to catheter-related infection rates.     

Infectious complications due to central venous polymeric catheters

Due to the multitude of invasive procedures of today's intensive care medicine, infections from central venous catheters have gained increasing attention. The incidence of bacteremias arising from such devices ranges from less than 0.1 to 0.6 cases per 100 catheter-days. Factors influencing the incidence of catheter-associated infections are related to patient characteristics as well as the purpose and material of the catheter. Silicone catheters seem to carry a lower risk of infection than common polytetrafluorethylene catheters. The most frequently isolated bacteria in catheter-associated infections are coagulase-negative and coagulase-positive staphylococci, enterococci, and pseudomonas species. Septicemias due to Candida albicans frequently complicate the course of immune-compromised patients receiving total parenteral nutrition (TPE). Catheter-associated bacteremias (CAB) can arise from the contaminated hub, from which pathogens migrate intraluminally to the blood stream. When the catheter entry site is infected, bacteria may reach the blood via the extraluminal route and cause septicemia. Endemic outbreaks of CAB often originate from contaminated infusion fluids. As the clinical presentation of "catheter infections" is often uncharacteristic and insidious, a definite diagnosis depends on bacteriological examination of the catheter. Quantitative and semiquantitative culture techniques of the catheter tip help to distinguish colonization from contamination by numbers of colony-forming units per milliliter culture medium. Preliminary results can be obtained by simple Gram or acridine-orange staining of the catheter tip. The most important prophylactic measures to prevent CAB are strictly aseptic conditions when catheters are placed and meticulous care thereafter, preferably by specially trained nurses or "TPE teams".(ABSTRACT TRUNCATED AT 250 WORDS)     

Bacterial colonization in hemodialysis temporary dual lumen catheters: a prospective study

AIMS: The use of hemodialysis temporary dual-lumen catheters is often complicated by infections, which may be a significant cause of death among patients with end stage renal disease (ESRD). The aim of this study was to assess the incidence of bacteremia and bacterial colonization related to non-tunneled, non-cuffed, dual-lumen temporary catheters in patients with ESRD submitted to hemodialysis. METHODS: This study included 29 patients with ESRD. After catheter implantation, patients were monitored throughout the period of catheter permanence by means of blood samples collected weekly from a peripheral vein. Bacteria were isolated and identified according to CLSI recommendations. When catheters were removed for any reason, their tips were evaluated microbiologically. RESULTS: A total of 194 blood samples from the 29 patients implanted with 55 catheters were analyzed. Of these, 15.5% (30 samples) demonstrated bacterial growth, principally Staphylococcus epidermidis (64.5%). Twenty patients (68.9%) presented at least one positive blood culture during follow-up. The median time for catheter colonization was 18.5 days (95% CI: 16.8-30.3). Of the 55 catheters implanted, 28 (50.9%) showed bacterial colonization, corresponding to 23.4 episodes/1000 catheter/days and 9.2 episodes of bacteremia /1000 catheter/days. Fifteen of 28 catheter tips analyzed showed bacterial growth (53.5%). In 14 of these (93.3%), there was agreement between the isolates from the catheter tip and blood cultures. Of 24 episodes of positive blood cultures from 20 different patients in 17 episodes (70.8%), the patients showed no clinical signs or symptoms of bacteremia. CONCLUSIONS: The high incidence of catheter colonization, the correlation between blood and catheter tip cultures, and the occurrence of frequent cases of asymptomatic bacteremia justify the proposal of routine peripheral blood collections to monitor patients undergoing hemodialysis with temporary dual-lumen catheters.     

Bladder management after total joint arthroplasty

This study was undertaken to determine the impact of an indwelling Foley catheter on bladder dysfunction and incidence of urinary tract infections after total joint arthroplasty. A prospective randomized controlled trial was conducted assigning use of an indwelling Foley catheter (group 1) or intermittent catheterization (group 2) for 48 hours following operation. Postoperative cultures were obtained on days 2 and 5, and the number of intermittent catheterization events and void and catheterization volumes were recorded. Concurrent cost-effectiveness analysis was conducted. One hundred nineteen of 174 consecutive patients having elective primary total joint arthroplasty completed the study. Five of 62 patients (8%) in group 1 and 7 of 57 patients (12%) in group 2 developed urinary tract infections (NS, P = .45). Twenty patients (35%) in group 2 and 12 (19%) in group 1 required straight catheterization for inability to void 48 hours after surgery (P = .05). Seventeen patients (35%) in group 2 and eight patients (16%) in group 1 required straight catheterization after epidural analgesia was discontinued (P = .024). Bladder management by indwelling Foley catheter saved more than 150 minutes of direct nursing contact per patient and $3,000 in total hospital costs. Indwelling Foley catheters reduced the frequency of postoperative urinary retention, were less labor intensive than intermittent straight catheterization, and were not associated with an increased risk of urinary infection. In the setting of epidural anesthesia and postoperative analgesia for total joint arthroplasty, management by indwelling catheter is a cost-effective strategy to facilitate postoperative return of normal bladder function.     

Early identification of bacteria leading to central venous catheter contamination

Catheter-related bloodstream infections (CRBSI) are a common problem in patients after central venous catheterization. Using DNA analysis we compared bacteria found on the tip of central venous catheters removed because of clinical signs of CRBSI with bacteria found on needle, dilator, and guidewire used for insertion of these catheters. In five of seven central venous catheters removed because of clinical signs of CRBSI, bacteria on the catheter tip were genetically identical to bacteria found on the insertion device, proving that catheter contamination in these cases was caused by contacting bacteria during the initial puncture. These findings may be important for antibiotic prophylaxis or therapy in patients at risk for CRBSI. IMPLICATIONS: In five of seven central venous catheters removed because of clinical signs of catheter-related blood infections, DNA analysis showed bacteria found on the catheter tip to be identical with bacteria found on the puncture kits used for insertion of these catheters.     

Catheter-related infections in burn patients at the Burn Centre of the University Hospital in Ostrava

We need central venous catheters (CVCs) in management of critically ill patients with severe burns, either for the administration of fluids or monitoring hemodynamic status. Central venous catheterization may cause different early or late complications, which depend on the physician's erudition, the quality of the catheters and quality of Intensive Care Unit (ICU) nursing care for insertion. 272 CVCs were inserted in 114 both adult and pediatric patients from 2004 to 2006 in the ICU of the Burn Centre in Ostrava. The average insertion length of the catheter was 10.2 days, and the average total length of catheterization was 24 days. The total number of catheter-days was 2768. All catheter tips removed were routinely cultured. The most frequent infecting pathogens were coagulase-negative Staphylococci. Peripheral blood cultures were examined in case of fever. Bacterial findings from wounds, sputa and urine were monitored in all patients. No exogenous catheter sepsis according to Maki's criteria occurred in our study group. Endogenous catheter colonization with positive peripheral blood culture and bacteraemia occurred in 4 cases, which means an incidence density of 1.44 endogenous colonizations per 1000 catheter-days. The quality of used catheters and particularly the technique of placement and maintenance of catheters are considered crucial for good results in the ICU of Burn centre in Ostrava.     

Antimicrobial therapy of Broviac catheter infections in pediatric hematology oncology patients

Long-term therapy of pediatric oncology patients has been facilitated by permanent indwelling venous catheters. Over a 3-year period, 54 Broviac catheters were placed in 43 oncology patients and two hemophiliacs. There were 20 episodes of sepsis in 14 patients and the most common bacteria were S epidermidis (4), S aureus (4), and K pneumoniae (3). Catheter exit site infections occurred ten times in six patients; S aureus eight of ten. Antibiotic therapy without catheter removal was successful in 18 of 20 children with catheter sepsis and 8 of 10 patients with exit site infections. These data strongly suggest that although catheter-related infections are common, removal of Broviac catheters is not required for successful treatment of the infection.