The risk of sepsis induced via the deep venous approach]

In order to determine the sepsis induced by the practice of canalizing the deep venous sector in revascularized patients, 43 catheters removed from 43 patients were cultured; no sepsis induced by this practice was found and 13 catheters had positive cultures, which amounted to 30.3% of the sample under study; five catheters (38.4%) with positive cultures belonged to patients who showed no sepsis; eight catheters (61.5%) with positive cultures corresponded to patients who showed septic focci. The average stay was 4.07 days. The germ most frequently found was negative coagulase staphylococcus.     

Bacteriological studies of the secretions obtained from the endotracheal tube removed from patients recently revascularized]

In cultures of secretions from 101 distal ends of endotracheal tubes removed from patients recently operated on due to several vascular affections, 41.6% of them were positive to different germs: pathogenic (7.9%), potentially pathogenic (12.9%), habitual in the oropharynx (3.9%), opportunistic (4.9%), contaminating (0.9%). Out of the 18.8% of patients recently operated on for acute inflammatory pneumopathy, 68.4% of them had positive cultures of the secretions in the distal ends of the removed endotracheal tubes. Hemocultures were carried out in 34.7% of the patients and 17.1% of them were found positive, although the germs found in the endotracheal tubes and the hemocultures were different. In the immediate postoperative period 48.5% of the gastric pH test were carried out and it was found that 37.6% of them were lower than 4, and 10.9% were higher than 4.1. Among the diseased, 28.6% had acute inflammatory pneumopathy and positive cultures of the secretions in the endotracheal tubes removed.     

A prospective study of a new protocol for 'in situ' diagnosis of central venous catheter related bacteraemia

59 patients with suspected central venous catheter related bacteraemia (CRB), while receiving parenteral nutrition, were studied prospectively. 41 (Group 1) were managed conservatively: cultures were taken from the catheter hub lumen, skin at the catheter entry site and peripheral blood; the catheter was then heparinised and locked for 24-48 h. The catheter was withdrawn only if cultures were positive; otherwise parenteral nutrition was resumed. In 18 patients the catheter was immediately withdrawn (Group 2) and the same cultures plus tip culture were performed. 13 patients of Group 1 with positive hub or skin cultures, had their catheters removed and 12 had blood cultures matching for the same micro-organism. Negative skin and hub cultures had a negative predictive value for CRB of 96%. A positive hub culture had a 100% positive predictive value for CRB. CRB was diagnosed in 11 patients out of the 18 in whom catheters were withdrawn immediately (Group 2). Thus, 1 out of 41 catheters and 7 out of 18 catheters were removed unnecessarily in Groups 1 and 2 respectively (p = 0.001, Fisher's test). In all, 24 CRBs were documented and 15 were due to coagulase negative staphylococci. The catheter hub was the commonest origin of CRB followed by the infusate and the skin. In febrile patients on parenteral nutrition, negative skin and hub cultures accurately predict or rule out CRB and should be used more often to avoid withdrawal of sterile catheters.     

Guidewire catheter exchange with triple culture technique in the management of catheter sepsis

We report 70 total parenteral nutrition (TPN) patients who received guidewire catheter exchange for suspected sepsis during their hospitalization. To diagnose catheter-related sepsis (CRS) and catheter infection (CI), we used a system of pre- and postexchange catheter blood cultures and a catheter tip culture. There were 27 catheter exchanges with positive cultures. The rate of definite CRS/CI (eight instances) was 6.8% of catheters exchanged and 3.5% of all catheters at risk. Probable CRS/CI (11 instances) was seen in 9% of exchanged catheters and 5% of at risk catheters. Thus, 19/27 positive cultures were presumed to represent definite or probable CRS/CI. Coagulase negative Staphylococcus (SCN) was the most frequently isolated organism. Simple catheter exchange was usually effective treatment of CRS/CI when SCN was the offending organism. The salvage rate of catheters exchanged for suspected sepsis or after a positive blood culture was 84%. Only 7% of exchanged catheters had to be removed. Guidewire exchange with triple culture technique was without mechanical complications. We recommend this technique to monitor central venous catheters in patients receiving TPN since it is simple, essentially painless to perform, and easily interpreted.     

Prophylaxis against microbial colonization of venous catheters

A total of 85 central venous catheterizations in 73 patients were subjected to a prospective study on prophylaxis against infectious complications. Bacterial growth was found in blood cultures in five cases (6 per cent) and in cultures from catheter tips in 23 cases (27 per cent). The most important route of infections was shown to be the catheter connection. Flaming of the connection when changing the giving set did not reduce the risk of catheter tip colonization. Catheter-related thrombosis was found in 33 of 73 phlebographs (45 per cent). There was a significant relationship (p less than 0.05) between thrombotic findings and positive catheter tip cultures. Reduction of the risk of thrombosis by anticoagulant therapy would therefore seem indicated as prophylaxis against bacterial complications.     

Which central venous catheter for neonatal use?

Complications in 100 percutaneous central venous catheters used for parenteral nutrition were monitored prospectively in patients on a regional neonatal medical and surgical unit. Infants were randomly allocated to receive either a Vygon Epicutaneous catheter or Dow Corning silastic tubing. The majority of lines -63 - were removed electively when parenteral feeding was no longer required. The most common serious complication was catheter sepsis for which 11 lines were removed; all patients made a complete recovery. Minor mechanical complications were encountered with 17 catheters. There was no difference in performance or complication rate comparing the two types of catheter. Percutaneous central venous catheters provide a suitable and safe means of administration of parenteral nutrition to preterm infants over an extended period of time.     

Clinical predictors of infection of central venous catheters used for total parenteral nutrition

To identify predictors of infection in catheters used for total parenteral nutrition (TPN), clinical and microbiological data were prospectively collected on 169 catheter systems (88 patients). Based on semiquantitative catheter cultures, infection was associated with a positive insertion site skin culture taken close to the time of catheter removal (relative risk [RR] = 4.50), especially one yielding greater than or equal to 50 colonies of an organism other than coagulase-negative staphylococci. Infection was also associated with erythema at the insertion site greater than 4 mm in diameter (RR = 2.93). In a subset of 67 catheters for which blood cultures were obtained, infection was also associated with a positive peripheral venous blood culture (RR = 5.90) and a positive central venous blood culture obtained through the catheter (RR = 5.44). Based on a logistic regression model, periodic cultures of the insertion site should be useful in evaluating subsequent fever in stable patients with indwelling central venous catheters. Another source of fever is likely if inflammation is absent and there is either no colonization or there is colonization by less than 50 colonies of coagulase-negative staphylococci at the insertion site. Conversely, the catheter should be removed and cultured semiquantitatively if the site is colonized by an organism other than coagulase-negative staphylococci. We suggest that blood culture results add little to the risk estimate in these situations.     

Percutaneous, tunneled silicone elastomer central venous catheters for total parenteral nutrition: low sepsis and thrombosis rate. A prospective study of 315 catheters

Silastic catheters were inserted by the percutaneous route, and tunneled subcutaneously, in 315 patients who needed venous access for total parenteral nutrition. The catheters were managed with a daily program that included heat sterilization of the metal hub with an electrical soldering iron. This study aimed to evaluate prospectively the incidence of catheter-related sepsis and thrombosis. There was one case of pneumothorax. All catheters were x-rayed post-insertion: eight catheters were malpositioned initially. The median catheter duration was 18 days with a range of 2-138 days. The total duration was 240 catheter-months. Twenty-seven catheters were removed due to mechanical problems. Nine were removed because of suspected sepsis; six patients had negative blood and catheter cultures, while three grew pathogens. The sepsis rate was thus 0.95%. There were no clinical signs of thrombosis. Pull-out venography was performed in 93 patients. Fibrin sleeves were seen in the majority of cases. Two patients had wall-adherent, non-occlusive thrombus masses (2%); they both had proximal catheter positions. We conclude that there is a low risk of catheter-related sepsis and thrombosis with this technique.     

Central Venous Catheter Salvage in Home Parenteral Nutrition Catheter‐Related Bloodstream Infections

Background: Catheter‐related bloodstream infections (CRBSIs) are a serious complication in the provision of home parenteral nutrition (HPN). Antibiotic salvage of central venous catheters (CVCs) in CRBSI is recommended; however, this is based on limited reports. We assessed the efficacy of antibiotic salvage of CRBSIs in HPN patients. Materials and Methods: All confirmed CRBSIs occurring in patients receiving HPN in a national intestinal failure unit (IFU), between 1993 and 2011, were analyzed. A standardized protocol involving antibiotic and urokinase CVC locks and systemic antibiotics was used. Results: In total, 588 patients were identified with a total of 2134 HPN years, and 297 CRBSIs occurred in 137 patients (65 single and 72 multiple CRBSIs). The overall rate of CRBSI in all patients was 0.38 per 1000 catheter days. Most (87.9%) infections were attributable to a single microorganism. In total, 72.5% (180/248) of CRBSIs were salvaged when attempted (coagulase‐negative staphylococcus, 79.8% [103/129], Staphylococcus aureus, 56.7% [17/30]; polymicrobial infections, 67.7% [21/30]; and miscellaneous, 66.1% [39/59]). CVC salvage was not attempted in 49 episodes because of life‐threatening sepsis (n = 18), fungal infection (n = 7), catheter problems (n = 20), and CVC tunnel infection (n = 4). Overall, the CVC was removed in 33.7% (100/297) of cases. There were 5 deaths in patients admitted to the IFU for management of the CRBSI (2 severe sepsis at presentation, 3 metastatic infection). Conclusions: This is the largest reported series of catheter salvage in CRBSIs and demonstrates successful catheter salvage in most cases when using a standardized protocol.     

Long term parenteral therapy by percutaneous tunneled silicone central venous catheter--a follow-up of 300 catheters

We have developed a technique for the management of central venous catheters which incorporates percutaneous insertion and daily care for routine use in different wards. A follow-up of the first 300 catheters is presented. When intravenous therapy was planned for more than two weeks, a silicone rubber catheter was introduced percutaneously with a skin tunnel and the position of the tip in the lower superior vena cava checked by venous pressure measurement. The metal hub of the catheter was disinfected daily by heating with a modified soldering iron which has been proved to be effective by in vitro testing with different microorganisms. The external jugular vein was used in 164 cases (55 per cent) the internal jugular vein in 115 (38 per cent) and the remaining catheters were inserted by the subclavian or antecubital route. Correct positioning was obtained in 96 per cent and serious early or late complications were rare there being only one case of septicaemia in a total treatment period of 270 months. One patient developed a lung infarct, but no case of pneumothorax has been seen. The mean duration of the catheters was 27 days (range 1-239) and the common reasons for termination were cessation of need in 84 per cent, mechanical obstruction in 6 per cent and inadvertent removal in 6 per cent. The described method has proved to be safe and to function well on ordinary wards.     

When should a urine specimen be examined after removal of a urinary catheter?

Catheter urine specimens (CSUs) were taken from 72 patients with short term urinary catheters just before the catheter was removed. The patients were assessed to see whether this specimen influenced their management. Their subsequent urinary symptoms were followed, and daily mid stream urines (MSUs) compared with the initial CSU to see if the initial CSU gave an accurate indication of the likelihood of infection when the catheter was removed. Only one patient was given antimicrobial therapy as a consequence of the initial CSU, and 18 patients (25 per cent) showed significant growth on the CSU but no growth or a non-significant growth on subsequent MSUs. It would appear that CSUs taken prior to the removal of urinary catheters are of limited value.     

Incidence of fever and bacteriemia following flexible fiberoptic bronchoscopy: a prospective study

The latest American Heart Association (AHA) statement for preventing infectious endocarditis, has not recommended prophylactic antibiotic therapy prior to fiberoptic bronchoscopy (FB) except for patients with preexisting predisposing cardiac conditions. Our aim was to determine the incidence of bacteriemia and fever following FB in our experience and compare with those which have been mentioned in AHA guideline as well as other studies. Venous blood of 85 consecutive patients was evaluated for both aerobic and anaerobic cultures before (for detecting possible previous bacteriemia) and after FB. None of the patients were treated with antibiotics prior to the procedure. All the patients were examined during the first 24 hours after FB for detecting fever defined as temperature more than 38 °C. Positive hemocultures were noted in 7 (8.2 %) patients after FB examination. Coagulase negative Staphylococcus, coagulase positive Staphylococcus, beta haemolytic Streptococcus, Citrobacter freundii and Streptococcus viridans were found in 4, 1, 1 and 1 cultures of patients, respectively. By excluding 6 contaminated samples, the rate of bacteriemia reduced to 1 (1.1%) patient in whom the identical pathogen (Streptococcus viridans) was found both in bronchial lavage and venous blood culture. We also found fever in 9 (10.5 %) cases in the first 24 hours following the bronchoscopy. Our results were in consistent with AHA recommendations regarding prevention of infectious endocarditis as a practical gridline in patients who schedule for FB. Besides, transient fever following bronchoscopy is a common self-limited event which does not need medical intervention.     

中心静脉导管留置后病原菌感染的临床研究

目的分析中心静脉导管引起病原菌感染情况及相关因素。方法对笔者所在医院2008年6月～2011年5月258例行中心静脉置管患者送检的标本进行回顾性分析，总结感染相关因素。结果中心静脉导管培养阳性60例，阳性率为23．3％，中心静脉导管培养阳性患者中，老年组与非老年组差异有统计学意义（P〈0．05），留置部位差异有统计学意义（P〈0．05）。结论机体抵抗力低下、老年患者、置管部位不当是高危因素，应采取综合性防范措施。     

Hickman catheter complications in marrow transplant recipients

The complications associated with the insertion and use of 95 single lumen and 312 double lumen Hickman right atrial catheters in 357 marrow transplant recipients were retrospectively analyzed. Three-hundred (84%) first inserted catheters were in place for a median of 93 days (range, 16-209) without complications and were removed electively. Thirty-nine (9.6%) of all catheters were removed for infections and 24 (5.9%) for mechanical complications. Ninety-five patients (26.6%) had 111 episodes of septicemia involving 128 separate organisms and 25 patients had 25 episodes of localized catheter infection with 26 separate organisms. The most frequently isolated organism was coagulase-negative staphylococcus. Twelve of 24 removals due to mechanical complications were caused by accidental pulling of the catheter by the patient.     

Risk factors for central venous catheter-related vascular erosions

Risk factors for superior vena cava perforations following central venous catheterization for total parenteral nutrition were identified in a retrospective study of 1058 catheters in 853 patients; 540 of these catheters were size 16-gauge (51%) and 518 size 14-gauge (49%). Of the size 14-gauge catheters, 274 (53%) were right-sided and 244 (47%) were left-sided subclavian catheters. Four patients (0.4%) had superior vena cava perforation. All had left-sided large bore 14-gauge catheters. All patients experienced acute symptoms and all had pleural effusions. There was no mortality directly related to vascular erosions. Two risk factors were identified for this complication: (1) catheters originating from the left side (p less than 0.05), or (2) large catheters (size 14-gauge or larger) (p less than 0.01). We conclude that large bore or left-sided central venous catheter placement represents an increased risk of superior vena cava perforation.     

重症监护病房中心静脉导管相关性血流感染病原菌及相关因素分析

目的探讨医院重症监护病房(ICU)中心静脉导管导管相关性血流感染(CRBSI)的病原菌分布特点及其耐药情况,并分析CRBSI的相关因素。方法对医院各科ICU 2008年1~12月所有放置中心静脉导管进行回顾性分析。结果109例患者总置管日2456 d,共送检165份中心导管尖端和283份血培养标本,导管53例阳性,阳性率为32.1%,与导管尖端培养出同一种细菌的血培养14例,导管尖端细菌定植率为21.6‰,感染率为5.7‰;引起CRBSI病原菌主要是凝固酶阴性葡萄球菌(28.6%)、金黄色葡萄球菌(21.4%)和白色假丝酵母菌(21.4%)。结论研究显示,引起CRBSI的菌株耐药率非常高,应加强导管管理的全程监控。     

Improved vascular access for patients receiving chemotherapy

Indwelling central venous catheters were used for vascular access in 25 oncology patients. The lines were used for sampling, administration of blood products, chemotherapeutic agents, parenteral nutrients and occasionally plasmapheresis. The complication rate was no higher than in reported series in which the catheters were reserved for parenteral nutrition. We believe that a central venous cannula can be safely used as the sole means of vascular access in those patients with consequent psychological and practical benefits.     

Bacterial contamination of intravenous cannula injection ports and stopcocks

A prospective clinical study was undertaken to analyse the routes of bacterial contamination in infusion therapy. The infusion system was equipped with two membrane filters (0.45 μm), one in the infusion line and the other on the side port. The series comprised 122 days of parenteral nutrition in 44 patients. Bacterial cultures were performed from filters, catheters, skin and blood. Fourteen per cent of the filters on the side port and 3% of those in the infusion line showed bacterial growth. No correlation was found between positive filter cultures and positive catheter tip or blood cultures. Thrombophlebitis occurred in 5% of the patients. The study has shown that side ports are a common route of bacterial contamination of infusion systems, more common than infusion fluids. It is recommended that side ports, if used, be equipped with a bacterial filter.     

Microbiological analysis of blood culture obtained from children hospitalized at the Gastroenterology, Oncology and Daily Chemotherapy Wards of the Children's Memorial Health Institute in the years 1999-2002

The aim of the study was to examine correlations between the use of different kinds of intravascular catheters and the type of microorganisms isolated from blood cultures. Blood samples obtained from gastroenterology, oncology and daily chemotherapy wards were examined. The samples were taken from catheter and peripheral blood in situations where blood infection was suspected. In positive blood samples Gram-positive bacteria, especially methicillin-resistant coagulase negative staphylococci, were dominant. Enterobacteriaceae (Klebsiella sp., E. coli, Enterobacter sp.) were the most often isolated among Gram-negative bacteria. The share of Staphylococcus aureus, Gram-negative bacilli and fungi was greater in the case of samples taken from catheters. The domination of CNS is frequently connected with catheter colonisation or contamination of samples. Intravascular catheters predispose to Staphylococcus aureus, Gram-negative rods and fungal infections.