Sepsis from triple- vs single-lumen catheters during total parenteral nutrition in surgical or critically ill patients

Incidence of Sepsis in Central Venous Catheter-Bearing Patients with Hematologic Malignancies: Preliminary Results

Background

Indwelling central venous catheters (CVCs) are essential devices in the management of patients with hematological disorders treated with chemotherapy. However, their nature predisposes patients to unwanted complications.

Methods

CVC-related complications were retrospectively analyzed in 227 hematologic patients who were consecutively admitted to our hematology department between May 2002 and April 2004. Patients’ diagnoses comprised acute myeloid leukemia (36.8%), acute lymphoid leukemia (7.3%), lymphoproliferative disorders (28.3%), multiple myeloma (19.5%), myeloproliferative syndromes (5%) and others (3.1%). The CVCs used were polyurethane three lumen 7-Fr (111 patients) for chemotherapy and 12-Fr (114 patients) for chemotherapy and peripheral blood stem cell apheresis, plus two tunneled catheters.

Results

The pathological events were: bacteriaemias (n=46); occlusions (n=10); exit tunnel infections (n=8); thrombosis (n=6); lung emboli (n=2). Among febrile patients the bacteriemia frequency was 20%, of which 13.6% were CVC-related (with a higher incidence in leukemia patients (p=0.027). Among the isolates, gram-positive bacteria were found in 29 cases (23 CVC-related cases), and gram-negative bacteria in 16 cases (8 CVC-related cases). Only one patient had Candida albicans sepsis. At univariate and multivariate analysis significant risk factors for infection (p<0.0001) were only the number of days/catheters and neutropenia duration.

Conclusions

In our hematologic patients, the CVC complications were mainly septic, with only 10.1% of CVC-related bacteriemias, despite prolonged catheterization duration. Acute leukemia patients were at major risk for sepsis, probably due to a more severe neutropenia and prolonged catheterization duration.

; Hospital Infection Control Practices Advisory Committee. Guideline for Prevention of Intravascular-Device–Related Infections

The “Guideline for Prevention of Intravascular Device-Related Infections” is designed to reduce the incidence of intravascular device-related infections by providing an over view of the evidence for recommendations considered prudent by consensus of Hospital Infection Control Practices Advisor y Committee (HICPAC) members. This two-part document updates and replaces the previously published Centers for Disease Control's (CDC) Guideline for Intravascular Infections (Am J Infect Control1983;11:183-199). Part I, “Intravascular Device-Related Infections: An Over view” discusses many of the issues and controversies in intravascular-device use and maintenance. These issues include definitions and diagnosis of catheter-related infection, appropriate barrier precautions during catheter insertion, inter vals for replacement of catheters, intravenous (IV) fluids and administration sets, catheter-site care, the role of specialized IV personnel, and the use of prophylactic antimi-crobials, flush solutions, and anticoagulants. Part II, “Recommendations for Prevention of Intravascular Device-Related Infections” provides consensus recommendations of the HICPAC for the prevention and control of intravascular device-related infections. A working draft of this document also was reviewed by experts in hospital infection control, internal medicine, pediatrics, and intravenous therapy. However, all recommendations contained in the guideline may not reflect the opinion of all reviewers.

Catheter-related and infusion-related sepsis

This article focuses on the pathogenesis, diagnosis, prevention, and management of infectious complications of intravascular cannulation and fluid infusion. Although continuous vascular access is one of the most essential modalities in modern-day medicine, there is a substantial and underappreciated potential for producing iatrogenic complications, the most important of which is blood-borne infection. Clinicians often fail to consider the diagnosis of infusion-related sepsis because clinical signs and symptoms are indistinguishable from bloodstream infections arising from other sites. Understanding and consideration of the risk factors predisposing patients to infusion-related infections may guide the development and implementation of control measures for prevention.

epic3: national evidence-based guidelines for preventing healthcare-associated infections in NHS hospitals in England

National evidence-based guidelines for preventing healthcare-associated infections (HCAI) in National Health Service (NHS) hospitals in England were originally commissioned by the Department of Health and developed during 1998-2000 by a nurse-led multi-professional team of researchers and specialist clinicians. Following extensive consultation, they were first published in January 2001(1) and updated in 2007.(2) A cardinal feature of evidence-based guidelines is that they are subject to timely review in order that new research evidence and technological advances can be identified, appraised and, if shown to be effective for the prevention of HCAI, incorporated into amended guidelines. Periodically updating the evidence base and guideline recommendations is essential in order to maintain their validity and authority. The Department of Health commissioned a review of new evidence and we have updated the evidence base for making infection prevention and control recommendations. A critical assessment of the updated evidence indicated that the epic2 guidelines published in 2007 remain robust, relevant and appropriate, but some guideline recommendations required adjustments to enhance clarity and a number of new recommendations were required. These have been clearly identified in the text. In addition, the synopses of evidence underpinning the guideline recommendations have been updated. These guidelines (epic3) provide comprehensive recommendations for preventing HCAI in hospital and other acute care settings based on the best currently available evidence. National evidence-based guidelines are broad principles of best practice that need to be integrated into local practice guidelines and audited to reduce variation in practice and maintain patient safety. Clinically effective infection prevention and control practice is an essential feature of patient protection. By incorporating these guidelines into routine daily clinical practice, patient safety can be enhanced and the risk of patients acquiring an infection during episodes of health care in NHS hospitals in England can be minimised.

Selected pharmacokinetic issues of the use of antiepileptic drugs and parenteral nutrition in critically ill patients

OBJECTIVES

To conduct a systematic review for the evidence supporting or disproving the reality of parenteral nutrition- antiepileptic drugs interaction, especially with respect to the plasma protein-binding of the drug.

METHODS

The articles related to the topic were identified through Medline and PubMed search (1968-Feburary 2010) for English language on the interaction between parenteral nutrition and antiepileptic drugs; the search terms used were anti-epileptic drugs, parenteral nutrition, and/or interaction, and/or in vitro. The search looked for prospective randomized and nonrandomized controlled studies; prospective nonrandomized uncontrolled studies; retrospective studies; case reports; and in vitro studies. Full text of the articles were then traced from the Universiti Sains Malaysia (USM) library subscribed databases, including Wiley-Blackwell Library, Cochrane Library, EBSCOHost, OVID, ScienceDirect, SAGE Premier, Scopus, SpringerLINK, and Wiley InterScience. The articles from journals not listed by USM library were traced through inter library loan.

RESULTS

There were interactions between parenteral nutrition and drugs, including antiepileptics. Several guidelines were designed for the management of illnesses such as traumatic brain injuries or cancer patients, involving the use of parenteral nutrition and antiepileptics. Moreover, many studies demonstrated the in vitro and in vivo parenteral nutrition -drugs interactions, especially with antiepileptics.

CONCLUSIONS

There was no evidence supporting the existence of parenteral nutrition-antiepileptic drugs interaction. The issue has not been studied in formal researches, but several case reports and anecdotes demonstrate this drug-nutrition interaction. However, alteration in the drug-free fraction result from parenteral nutrition-drug (i.e. antiepileptics) interactions may necessitate scrupulous reassessment of drug dosages in patients receiving these therapies. This reassessment may be particularly imperative in certain clinical situations characterized by hypoalbuminemia (e.g., burn patients).

Access technique and its problems in parenteral nutrition - Guidelines on Parenteral Nutrition, Chapter 9

Catheter type, access technique, and the catheter position should be selected considering to the anticipated duration of PN aiming at the lowest complication risks (infectious and non-infectious). Long-term (>7-10 days) parenteral nutrition (PN) requires central venous access whereas for PN <3 weeks percutaneously inserted catheters and for PN >3 weeks subcutaneous tunnelled catheters or port systems are appropriate. CVC (central venous catheter) should be flushed with isotonic NaCl solution before and after PN application and during CVC occlusions. Strict indications are required for central venous access placement and the catheter should be removed as soon as possible if not required any more. Blood samples should not to be taken from the CVC. If catheter infection is suspected, peripheral blood-culture samples and culture samples from each catheter lumen should be taken simultaneously. Removal of the CVC should be carried out immediately if there are pronounced signs of local infection at the insertion site and/or clinical suspicion of catheter-induced sepsis. In case PN is indicated for a short period (max. 7-10 days), a peripheral venous access can be used if no hyperosmolar solutions (>800 mosm/L) or solutions with a high titration acidity or alkalinity are used. A peripheral venous catheter (PVC) can remain in situ for as long as it is clinically required unless there are signs of inflammation at the insertion site.

epic2: National evidence-based guidelines for preventing healthcare-associated infections in NHS hospitals in England

National evidence-based guidelines for preventing healthcare-associated infections (HCAI) in National Health Service (NHS) hospitals in England were commissioned by the Department of Health (DH) and developed during 1998-2000 by a nurse-led multi-professional team of researchers and specialist clinicians. Following extensive consultation, they were published in January 2001. These guidelines describe the precautions healthcare workers should take in three areas: standard principles for preventing HCAI, which include hospital environmental hygiene, hand hygiene, the use of personal protective equipment, and the safe use and disposal of sharps; preventing infections associated with the use of short-term indwelling urethral catheters; and preventing infections associated with central venous catheters. The evidence for these guidelines was identified by multiple systematic reviews of experimental and non-experimental research and expert opinion as reflected in systematically identified professional, national and international guidelines, which were formally assessed by a validated appraisal process. In 2003, we developed complementary national guidelines for preventing HCAI in primary and community care on behalf of the National Collaborating Centre for Nursing and Supportive Care (National Institute for Healthand Clinical Excellence). A cardinal feature of evidence-based guidelines is that they are subject to timely review in order that new research evidence and technological advances can be identified, appraised and, if shown to be effective in preventing HCAI, incorporated into amended guidelines. Periodically updating the evidence base and guideline recommendations is essential in order to maintain their validity and authority. Consequently, the DH commissioned a review of new evidence published following the last systematic reviews. We have now updated the evidence base for making infection prevention and control recommendations. A critical assessment of the updated evidence indicated that the original epic guidelines published in 2001 remain robust, relevant and appropriate but that adjustments need to be made to some guideline recommendations following a synopsis of the evidence underpinning the guidelines. These updated national guidelines (epic2) provide comprehensive recommendations for preventing HCAI in hospitals and other acute care settings based on the best currently available evidence. Because this is not always the best possible evidence, we have included a suggested agenda for further research in each section of the guidelines. National evidence-based guidelines are broad principles of best practice which need to be integrated into local practice guidelines. To monitor implementation, we have suggested key audit criteria for each section of recommendations. Clinically effective infection prevention and control practice is an essential feature of protecting patients. By incorporating these guidelines into routine daily clinical practice, patient safety can be enhanced and the risk of patients acquiring an infection during episodes of healthcare in NHS hospitals in England can be minimised.

Specific topics and complications of parenteral nutrition

BACKGROUND/AIMS

Total parenteral nutrition (TPN) has proven a tremendous advance in all disciplines in medicine but itself introduces a spectrum of possible complications related to both the parenteral nutritional solution as well as the technique of intravenous delivery. Our aim is to review the specific complications of TPN.

MATERIALS AND METHODS

This article presents a critical literature review of relevant topics in TPN-related complications-metabolic, infections, and nutrition related.

RESULTS

Special emphasis focuses on complications of TPN arising from thrombosis or infectious sequelae related to the central venous catheterization and metabolic complications involving the kidneys, bones, liver, and biliary tract.

CONCLUSIONS

Awareness and surveillance of TPN-related complications can prevent, potentially, some of these complications related to parenteral nutritional support.

Vascular access for home intravenous therapy in children

This review article describes the vascular access devices available for long-term vascular access in children, describes the procedures for implanting them and the sites available for this purpose, discusses the complications associated with catheter placement and how to avoid them, and compares the various catheter systems in terms of their advantages and disadvantages.

Vascular Access in the Adult Home Infusion Patient

The dependence of IV hyperalimentation programs on the achievement and maintenance of reliable vascular access in the home infusion patient population has necessitated a review of the current methods used to establish and maintain adequate long-term vascular access. Vascular access device-related complications are significant contributors to the medical course and costs associated with the care of home parenteral nutrition (HPN) patients. The purpose of this manuscript is to review current thoughts on the establishment of long-term vascular access for HPN with regard to techniques used, device selection, and associated complications.

Reduced colonization and infection with miconazole–rifampicin modified central venous catheters: a randomized controlled clinical trial

OBJECTIVE

Central venous catheters (CVC) are a major cause of nosocomial bloodstream infections. Catheters modified with miconazole and rifampicin that constantly and slowly release antimicrobial substances are assumed to be beneficial in reducing rates of colonization and catheter-related infections.

DESIGN AND SETTING

Prospective controlled non-blinded randomized clinical trial in two German university hospitals.

PATIENTS

223 adult inpatients with CVC between October 2000 and February 2002. Baseline characteristics, APACHE II score and therapeutic interventions were comparable.

INTERVENTION

Randomization to receive either a miconazole and rifampicin modified catheter (n=118) or a standard triple-lumen CVC (n=105). MEASUREMENTS, DEFINITIONS: Microbiological evaluation was done after CVC removal. A catheter was considered colonized if growth of > or =15 cfu was found by semi-quantitative roll-plate technique from a proximal or distal catheter segment. A catheter-related infection (CRI) was defined as a colonized catheter with local signs of inflammation. A catheter-related bloodstream infection (CR-BSI) was defined as a colonized catheter with isolation of the same organism from the patient's blood with accompanying clinical signs of infection.

RESULTS

A colonization of CVC was observed in six patients (5.1%) with a modified catheter and 38 patients (36.2%) with a standard catheter (P < 0.001). Five patients in the modified group (4.2%) and 18 in the standard group (17.1%) developed CRI (P=0.002). One assumed CR-BSI was detected in the standard group, with none in the modified group. No adverse effects related to the modified catheters and no antimicrobial resistance were observed.

CONCLUSION

CVC supersaturated with miconazole and rifampicin were associated with a significantly lower risk for catheter colonization and catheter-related infections compared to standard catheters.

Central venous catheter-related blood stream infections: incidence, risk factors, outcome, and associated pathogens

OBJECTIVE

To determine the incidence, risk factors, outcome, and pathogens of central venous catheter-related bloodstream infections (CVC-BSIs).

DESIGN

Prospective study.

SETTING

Escorts Heart Institute and Research Centre, New Delhi, India.

PARTICIPANTS

One thousand three hundred fourteen consecutive patients undergoing cardiac operations who were admitted to the intensive care unit with CVC.

INTERVENTIONS

All patients were assigned into CVC-BSI (n = 35) and non-CVC-BSI (n = 1,279) groups.

MEASUREMENT AND MAIN RESULTS

Of the 1,314 patients in the study, 35 (2.6%) had CVC-BSI. On univariate analysis, significant risk factors were use of multilumen catheters, coexistent infections, intra-aortic balloon counterpulsation (IABC), total ventilation hours, emergency surgery, acute physiology, age, chronic health evaluation score (APACHE II), and steroids. On multivariate analysis, duration of catheterization (24.5 +/- 10.9 v 6.1 +/- 3.2; p < 0.001), coexistent infections (57.11% v 2.61%; p < 0.001), IABC (77.1% v 4.1%; p = 0.005), and temperature (38.2 +/- 0.6 v 37.4 +/- 0.3; p < 0.001) were independent predictors of CVC-BSI. Pathogens isolated were Escherichia coli (47%), Acinetobacter species (11.7%), Enterobacter species (5.8%), Proteus species (5.8%), methicillin-resistant Staphylococcus species (11.7%), coagulase-negative Staphylococcus species (5.8%), and Candida (11.7%). The mortality rate in CVC-BSI was 22.9% as compared with 0.2% in non-CVC-BSI cases (p < 0.001).

CONCLUSION

By univariate analysis, the risk factors for CVC-BSI were use of multilumen catheters, duration of catheterization, total ventilation hours, IABC, emergency surgery, APACHE II score, coexistent infections, and steroids. On multivariate analysis, duration of catheterization, IABC, coexistent infections, and temperature were independent predictors of CVC-BSI. The mortality was increased with CVC-BSI.

Colonization and bloodstream infection with single- versus multi-lumen central venous catheters: a quantitative systematic review

There is a controversy as to whether the number of lumens in the central venous catheters may impact the incidence of catheter-related bloodstream infection. We performed a systematic search (MEDLINE, PREMEDLINE, Cochrane Library, EMBASE, BIOSIS Previews, CINAHL, HealthSTAR/Ovid healthstar, bibliographies, any language, to April, 2003) for full reports on randomized comparisons of single-lumen and multi-lumen catheters. Trials had to report on dichotomous data of catheter colonization or bloodstream infection. Meta-analyses were performed using a fixed effect model. Data were expressed as odds ratio (OR) and number-needed-to-treat (NNT) with 95% confidence interval (CI). Five randomized trials (1987-1995) with data on 255 single-lumen and 275 multi-lumen catheters were analyzed. Average insertion times were 8 to 21 days with multi-lumen catheters and 9 to 24 days with single-lumen catheters. In 4 trials, 23 of 176 (13.1%) multi-lumen and 26 of 177 (14.7%) single-lumen catheters were colonized (OR, 0.92; 95% CI, 0.49-1.72). In 5 trials, bloodstream infection occurred with 23 of 275 (8.4%) multi-lumen and with 8 of 255 (3.1%) single-lumen catheters (OR, 2.58; 95% CI, 1.24-5.37; NNT, 19; 95% CI, 11-75). For every 20 single-lumen catheters inserted, one bloodstream infection will be avoided that would have occurred had multi-lumen catheters been used. The risk of catheter colonization is not decreased. Although these conclusions are based on limited data, single-lumen catheters should be used whenever feasible.

Rates of infection for single-lumen versus multilumen central venous catheters: a meta-analysis

OBJECTIVE

Since the introduction of multilumen central venous catheters two decades ago, there has been controversy whether the additional lumens place patients with these catheters at higher risk for infection. Our objective was to determine the risk of catheter-related bloodstream infection (CRBSI) and catheter colonization in multilumen catheters compared with single-lumen catheters.

DATA SOURCE

Studies were identified by a computerized search of MEDLINE, EMBASE, CINAHL, Current Contents, and PREMEDLINE databases and by review of bibliographies and expert consultation. Studies comparing the prevalence of CRBSI or catheter colonization among single-, double-, and triple-lumen central venous catheters were included. We excluded studies if they included central venous catheters that were long-term, cuffed, tunneled, or coated with antibiotic or antiseptic agents.

DATA ABSTRACTION

Two independent reviewers abstracted data on: 1) risk factors for CRBSI and colonization, 2) outcome definitions used, 3) the absolute prevalence of CRBSI and catheter colonization, and 4) study design and quality.

DATA SYNTHESIS

A total of 15 studies met inclusion criteria. Summary odds ratios were calculated using a random-effects model. Although CRBSI was more common in multilumen catheters (summary odds ratios, 2.15; 95% confidence interval, 1.00-4.66), catheter colonization was not (summary odds ratios, 1.78; 95% confidence interval, 0.92-3.47). Tests for heterogeneity, however, suggested substantial variation by study. When only studies of higher quality were included, multilumen catheters were found not to be associated with a significant increase in CRBSI prevalence (summary odds ratios, 1.30; 95% confidence interval, 0.50-3.41).

CONCLUSIONS

Multilumen central venous catheters may be associated with a slightly higher risk of infection when compared with single-lumen catheters; however, this relationship diminishes when only high-quality studies that control for patient differences are considered. The slight increase in infectious risk when using multilumen catheters is likely offset by their improved convenience, thereby justifying the continued use of multilumen vascular catheters.

Clinical management of catheter-related infections

Central venous catheters represent a major source of nosocomial bloodstream infections, which cause considerable excess morbidity. It is currently unknown to what extent these infections contribute to mortality. Most catheter-related infections (CRIs) are caused by Gram-positive organisms (mainly coagulase-negative staphylococci). Definite diagnosis of CRI necessitates removal of the catheter in most cases. However, the recently described technique of differential time to positivity may allow diagnosis of CRI with the catheter left in place. Removal of the catheter has been standard clinical practice for the management of CRI in the past and is still recommended in many cases. In specific situations, such as infections of implanted catheters with coagulase-negative staphylococci, a trial of catheter salvage may be justified. In catheter-related bloodstream infection Staphylococcus aureus and Candida spp., the catheter should be removed immediately, due to the high risk of metastatic infection and increased mortality. A clinical work-up for the detection of additional foci (including transesophageal echocardiography in S. aureus infections) is advisable in these cases. All CRIs should be treated with antibiotics to which the causative agent has been shown to be susceptible. In addition to systemic antimicrobial therapy, antibiotic lock therapy may be applied, especially in patients with implanted long-term catheters if catheter salvage is attempted.

Critical care of patients with cancer. Surgical considerations

Surgical evaluation of and therapy for the critically ill cancer patient continue to present significant challenges despite, or perhaps in part because of, an ongoing technologic refinement of therapeutic modalities within a modern ICU.

Bacteremia associated with central venous catheter infection is not an independent predictor of outcomes

BACKGROUND

Infection is the leading complication of central venous catheters. In the setting of suspected line infection, the CDC recognizes only catheter-related bloodstream infection but not catheter infection without bacteremia, which is designated "colonization." To evaluate the hypothesis that catheter-related bloodstream infection has worse outcomes than catheter infection without bacteremia, we compared demographics, clinical data, and outcomes.

STUDY DESIGN

Analysis of catheter infections was performed on data collected prospectively for all episodes of infection occurring from December 1996 to September 1999 on the surgical services at a university hospital. Catheter tips were cultured only when infection was suspected. Catheter infection without bacteremia was defined as systemic evidence of infection, the presence of at least 15 colony-forming units on the catheter tip by a semiquantitative technique, and absence of bloodstream infection with the same organism as the catheter. Catheter-related bloodstream infection required the presence of bacteremia with the same organism as the catheter tip.

RESULTS

The 59 patients with catheter-related bloodstream infection had more coexistent infections than the 91 patients with catheter infection without bacteremia (2.9+/-0.1 versus 1.7+/-0.1; p=0.0001), most commonly pneumonia (37.3% versus 16.5%, p = 0.004) and urinary tract infections (28.8% versus 8.8%, p = 0.001). Catheter-related bloodstream infection was associated with an increased proportion of gram-negative organisms compared with catheter infections without bacteremia (29.5% versus 16.9%, p = 0.04) and a trend toward fewer gram-positive organisms (61.5% versus 73.7%, p = 0.07). There were no differences in APACHE II score, WBC, length of hospital stay, time from admission to fever, time from fever to treatment, normalization of WBC, days of antibiotics, defervescence, gender, presence of comorbidities, occurrence of colonization while in an ICU, or mortality rate (18.6% with bacteremia, 24.2% without; p = 0.42).

CONCLUSIONS

The presence of bloodstream infection in addition to catheter infection does not appear to alter outcomes. The definition of catheter infection perhaps should be extended to include catheter infections without bloodstream infection in the presence of systemic illness without another source.

Pneumococcal bacteremia associated with an infected central venous catheter

Pneumococcus (Streptococcus pneumoniae) bacteremia is a serious infection. Pneumococcus has never been implicated as a cause of a central venous catheter-related bacteremia. It has been isolated from the catheter tip only twice before, and in one case caused the infection of an infusion port device. We report case of a 41-year-old woman who developed pneumococcal bacteremia after 6 days of an indwelling central venous catheter. The catheter tip grew > 300 cfu of S pneumoniae by the roll-plate method described by Maki and colleagues. No other focus of infection could be found in this patient. To the best of our knowledge, this is the first reported case of pneumococcal bacteremia associated with an infected central venous catheter.

Catheter-Related Bloodstream Infection

Central venous catheters are associated with the vast majority of nosocomial, catheter-related bloodstream infections (CR-BSI). Despite identification of multiple effective methods for preventing CR-BSI, it remains an important clinical problem. Catheters coated with anti-infective substances, such as chlorhexidine and silver sulfadiazine or rifampin and minocycline, have shown promising results in recent clinical trials, but confirmatory studies by different investigators are still needed. Concern has also been raised about widespread use of clinically important antibiotics on catheter surfaces, which may promote the development of antibiotic resistance. More accurate and cost-effective methods of diagnosing CR-BSI are desirable. Recent studies have evaluated endoluminal brush sampling and differential blood culture growth rates, which may provide acceptable accuracy without requiring removal of long-dwelling catheters, but the accuracy of these techniques needs to be confirmed in other studies.

Risk reduction in the intensive care unit

Many potentially preventable complications occur in patients who receive intensive care. We have reviewed the epidemiology of three important complications (venous thromboembolism, stress-related upper gastrointestinal bleeding, and vascular catheter-related infection) and evaluated common preventive treatments to provide evidence-based recommendations for prevention. We used English language articles located by MEDLINE or cross-citation, giving preference to articles published in the last 10 years, meta-analyses, and clinical trials that were randomized, double-blinded, and used intention-to-treat analysis. We recommend prophylaxis against venous thromboembolism in most patients, whereas those without respiratory failure or coagulopathy may not require prophylaxis against stress-related upper gastrointestinal hemorrhage. Chlorhexidine gluconate is the preferred antiseptic for disinfecting the skin prior to and during intravascular catheterization. Central venous catheters impregnated with antibacterial or antiseptic agents should be considered in patients at high risk for vascular catheter-related infection. Finally, central venous, pulmonary arterial, and systemic arterial catheters should be changed only when clinically indicated.

Nontunneled central venous catheters in patients with AIDS are associated with a low infection rate

Patients with AIDS frequently require long-term central venous access devices for intravenous (IV) therapy. We reviewed the medical records of all HIV-infected patients at a single large urban hospital who had a central venous catheter (CVC) placed during a 1-year period to assess the overall complication rate, infection rate, and the microbiology of infectious complications. One hundred fifty-six catheters were inserted in 87 patients for 11,041 catheter days. These catheters (142 of 156) were primarily nontunneled, nonimplantable CVCs (NT-CVCs), and analyses were limited to these. Of these catheters, 79% were primarily used to treat disease caused by cytomegalovirus (CMV). The complication rate for the NT-CVCs was 5.1/1000 catheter days with a mean time to any complication of 106 days. The total infection rate of the NT-CVCs was 2.8/1000 catheter days, and the serious infection rate (bacteremia) for the NT-CVCs was 1.4/1000 catheter days. The mean time to a serious infection was 407 days. None of the following parameters was associated with an increased infection rate: HIV risk factor, indication for catheter, medications received via catheter, number of catheter ports, anatomic site of catheter insertion, or the presence of neutropenia. NT-CVCs were associated with low complication and infection rates that were comparable with historical rates seen in AIDS patients with tunneled and totally implantable central venous access devices. NT-CVCs may be a safe, cost-effective alternative to other central venous access devices in patients with HIV/AIDS.

Infection versus colonization in the critical care unit

Serious infections in the critical care unit are commonplace. However, distinguishing true infection from mere colonization is a difficult and often uncertain process that has been shown to result in both over- and under-treatment of patients. Antimicrobial agents used in the CCU setting are expensive and not without toxicities. This article discusses methods to differentiate colonization from infection.

Nutritional support of the hospitalized patient

Comprehensive care of patients in hospitals includes assessment of nutritional status and provision of appropriate support. This approach is facilitated by knowledge of the essential differences in metabolism between starved and stressed states. Nutritional assessment and care of patients in a hospital are based on answers to the following questions: Who gets it? When do they get it? How much do they get? What route is used to administer it? What kind do they get? What are common complications of enteral and parenteral support? What nutritional aspects are pertinent to common diseases?

Femoral venous access is safe in burned children: an analysis of 224 catheters

OBJECTIVE

To document the incidence of septic and mechanical complications associated with femoral venous catheters in a subgroup of patients thought to be at particularly high risk of both: young children with large burns.

DESIGN

An analysis of data collected prospectively on all femoral venous catheters placed during a 4-year period at a regional pediatric burn facility.

RESULTS

There were 224 femoral catheters placed in 86 children with an average age of 5.3 +/- 5.1 years and an average burn size of 38% +/- 23%. Catheters were left in place for a mean duration of 5.7 days. Catheter-related sepsis occurred with 4.9% of the catheters, and mechanical complications occurred in 3.5% of the patients. There was no statistically significant association between the risk of catheter sepsis and the placement of catheters through burned versus unburned skin. Similarly, the risk of sepsis was equivalent between lines placed over a guide wire and those placed of a new site.

CONCLUSION

Femoral venous catheters are safe in burned children and are associated with a low incidence of infectious and mechanical complications.

Care of central venous catheters for total parenteral nutrition

This report summarizes data obtained via a mailed questionnaire from 129 Department of Veterans Affairs (VA) hospitals regarding current practices in the care of central venous catheters (CVCs) used for total parenteral nutrition (TPN). The size of VA hospitals' acute medical-surgical beds ranged from 14 to 1320 (median 168) beds. Over 6000 patients annually received CVCs for TPN. Hospitals reported using triple-lumen catheters most frequently as their CVC for TPN (80.3%). A povidone-iodine scrub was used to prepare the skin for CVC insertion by 72.6% of reporting hospitals. Sixty percent of hospitals used transparent polyurethane dressings. Care of CVCs varied among hospitals. Catheter-related infection and sepsis rates were within the national average, although < 50% of responding hospitals provided data on these outcomes. The results of this survey point to the need for a national standardized database relative to patients receiving TPN via a CVC.

Peripheral infusion as the route of choice for intravenous nutrition: a prospective two year study

A central venous catheter (CVC) is widely regarded as the standard route for delivery of intravenous nutrition (IVN). Peripheral venous infusion avoids the morbidity of a CVC, but may require regular resiting of standard intravenous cannulae, or compromise of the nutritional quality of the feed, to avoid thrombophlebitis. Fine-bore catheters, designed for use in neonates, have been associated with a much lower incidence of phlebitis when used for peripheral IVN in adults, but reports have been limited to selected groups of patients. A prospective study of 302 courses of IVN is presented in which a peripheral vein was the route of first choice. The composition of the feed was determined by the patient's metabolic requirement, and was not compromised to facilitate peripheral venous infusion. In 51% of all courses of IVN the peripheral route alone was used; 76% of patients who received peripheral IVN required only one fine-bore catheter.

Infection resistance of surface modified catheters with either short-lived or prolonged activity

It has been suggested that the invasion of microbes into the catheter tract occurs mainly at the time of catheter insertion. To investigate whether the presence of an antimicrobial environment during the initial period after insertion is sufficient to reduce the risk of subsequent catheter colonization and infection, we evaluated the use of benzalkonium chloride-heparin bonded (BZK-hep) central venous catheters, which exhibit short-lived surface antimicrobial activity, using a rat subcutaneous model. Bacterial adherence on these catheters was determined, seven days after challenging the insertion site with 10(6) cfu of Staphylococcus aureus. A chlorhexidine-silver sulphadiazine impregnated catheter (Arrowg+ard), with longer lasting surface antimicrobial activity, and a hydrophilic coated catheter ('Hydrocath'), were evaluated simultaneously for comparison. Unlike Arrowg+ard antiseptic catheters, BZK-hep 'Hydrocath' and control catheters had significant bacterial adherence on their surface. Arrowg+ard catheters were colonized in 19% of the animals compared with 100% in all the other groups (P < 0.05; mean cfu cm-2: control = 1.3 x 10(6), BZK-hep = 4.3 x 10(5), Hydrocath = 2 x 10(5), Arrowg+ard = 71). Our results indicate that catheters with short-lived surface antimicrobial activity are unlikely to provide long-term protection against catheter-related infection. The efficacy of Arrowg+ard catheters may be due to the initial high rate of kill and prolonged antimicrobial activity.

Decreased bacterial adherence and biofilm formation on chlorhexidine and silver sulfadiazine-impregnated central venous catheters implanted in swine

OBJECTIVE

To determine if antiseptic central venous catheters impregnated with silver sulfadiazine and chlorhexidine (antiseptic) reduce bacterial adherence and biofilm formation without producing local or systemic toxicity.

DESIGN

Prospective, randomized, controlled trial.

SETTING

Experimental laboratory in a university teaching hospital.

SUBJECTS

Ten outbred New Hampshire pigs.

INTERVENTIONS

Nonimpregnated (control) and antiseptic-impregnated catheters were inserted intravascularly into swine for 7 days. After explantation, the catheters were assessed for bacterial adherence and biofilm formation, and the surrounding tissue was assessed for signs of toxicity. Before retrieval, systemic concentrations of antimicrobials were determined.

MEASUREMENTS AND MAIN RESULTS

Sequential roll plate and centrifuging were used to detect moderately and tightly adherent bacteria on the outer and luminal surfaces of the catheter. The presence of biofilm was detected by scanning electron microscopy. Tissues surrounding the catheters were examined histopathologically; systemic concentrations of chlorhexidine, sulfadiazine, and silver were determined by atomic absorption and high-performance liquid chromatography. As compared with the controls, antiseptic catheters had significantly (p < .01) fewer moderately and tightly adherent bacteria on outer and luminal surfaces, and fewer adherent bacteria when outer surfaces alone were examined (p < .01). Scanning electron microscopy showed bacterial biofilm and adherence on the control catheters but not on the antiseptic catheters. There were no abnormal histopathologic changes associated with the test catheter, and serum concentrations of the antibacterial agents were shown to be within nontoxic ranges.

CONCLUSION

The antiseptic-impregnated catheters prevented bacterial adherence and biofilm formation and produced no local or systemic toxicity.

Central venous catheter infections: concepts and controversies

Central venous catheters (CVCs) are widely used in critically ill patients in intensive care units. However, infectious complications are common and may limit their utility. We critically review the literature to determine the impact of CVC design and composition, insertion site selection, insertion procedures, care and removal of temporary CVCs on infectious complications. Relevant articles were identified and selected for review using a database search (Medline and manual of the English language literature) based upon study design and sample size with an emphasis on prospective randomized trials. To minimize infectious complications and maintain a reasonable cost-benefit ratio, we recommend: i) use a single lumen catheter unless clear indications for a multi-lumen catheter exist; ii) insert the catheter via the subclavian vein if no relative contraindication exists (bleeding diathesis, positive pressure ventilation); iii) disinfect the insertion site employing sterile technique; iv) apply a dry, sterile dressing and change the dressing every other day; v) inspect the insertion site for signs of infection and remove the catheter if pus is present; vi) if a catheter-related infection is suspected, change the catheter over a guidewire and culture the distal segment. The replacement catheter should be removed if an original catheter segment culture is positive.

Community-acquired bacteremias from tunneled central intravenous lines: results from studies of a single vendor

Tunneled central intravenous catheters are a common method for rendering prolonged outpatient intravenous therapy. Their safety, however, has not been well studied. We conducted a retrospective evaluation of bacteremias associated with tunneled central intravenous catheters managed by a single home health care vendor during a 1-year period. All catheters were inserted in the operating room under sterile conditions. To calculate total line days, the dates of catheter insertion and removal were obtained from either the hospital operating room or the home health care agency. Catheter care was conducted according to written protocols. Total line days were calculated. Community-acquired bacteremia (defined as bacteremia occurring more than 6 days after the patients' discharge from the hospital) was determined from records available in the infection control department. Sixty-eight patients received intravenous therapy from the vendor during the 1-year study period. Total line days were 5548 (median 52 days/patient). Eleven episodes of bacteremia occurred in five patients, providing an incidence density rate of 2.0 infections/1000 catheter days. The most frequent bacteria encountered were Staphylococcus epidermidis (five), Klebsiella pneumoniae (two), and Acinetobacter calcoaceticus var anitratus (two). Median time to bacteremia was 103 days. Two patients, both younger than 4 years, accounted for seven of the infections; both had short-bowel syndrome. On the basis of historical comparisons, outpatient intravenous therapy appears to be associated with a lower risk of bacteremia than in-hospital therapy. These data can provide quality improvement information and may be a means for comparing home infusion therapy vendors.

Femoral venous catheters: a safe alternative for delivering parenteral alimentation

Femoral vein catheterization is an alternative method of obtaining central venous access. Placement of femoral venous catheters (FVCs) is possible in the majority of patients, suitable for most indications, and associated with a low complication rate during insertion. We wished to determine the incidence of infections or other complications resulting when parenteral nutrition was delivered through FVCs. Fifty-two patients were followed from a hospital-wide population including patients in the critical care units. Triple-lumen catheters were placed by using the sterile Seldinger technique, and sites were examined daily for inflammation. Bacteriologic surveillance was accomplished by submitting the catheter tip for semiquantitative cultures. If catheter line sepsis was suspected, blood samples for cultures were drawn through the catheter and peripherally. The rate of occurrence of colonized catheters was 9.6% (five of 52), and catheter sepsis was found in one case (1.9%). Other than inflammation at six (11.5%) of 52 catheter sites, noninfectious complications of FVCs were not found. On the basis of these findings, we consider FVC-delivered parenteral alimentation a safe and effective alternative to other forms of central venous access.

The effect of catheter type and site on infection rates in total parenteral nutrition patients

Infections pose a major problem in patients receiving total parenteral nutrition. Controversy continues concerning the effect of catheter type (triple-, double-, single-lumen, or pulmonary artery), insertion site (subclavian, internal jugular, or femoral vein), and the incidence of catheter-related infections. We retrospectively studied multi-lumen catheter use for total parenteral nutrition over a 6-month period in 192 patients, a total of 3334 catheter days. Nonintensive care unit catheters were inserted by the Nutrition Support Service, and intensive care unit catheters were inserted by the intensive care unit staff. All catheters were cared for using Nutrition Support Service protocols, with multi-lumen catheters changed every 7 to 10 days and pulmonary artery catheters changed every 4 days. Infections were determined by semiquantitative cultures (> 15 colonies/plate). The incidence of infections for triple-lumen catheters was 5 (subclavian), 17 (internal jugular), and 36% (femoral) respectively; total infection rate for triple-lumen catheters was 10%. Infection rates for pulmonary artery catheters were 4 (subclavian), and 6% internal (jugular site), respectively, the overall infection rate was 5%. There were no differences in infection rates at any site based on catheter type; however, when triple-lumen catheter sites were compared, the differences were significant (p < .001 vs subclavian, chi 2). Catheter duration was 7.8 days (subclavian),, 7.3 days (internal jugular), and 4.6 (femoral) days. These data suggest that the use of multi-lumen catheters for total parenteral nutrition is safe, that there is a benefit associated with the subclavian route, and that the femoral site should be avoided.

Complications and survival of multilumen central venous catheters used for total parenteral nutrition

In a prospective study of 879 triple-lumen catheters, 219 pulmonary artery catheters, 31 double-lumen and six single-lumen catheters used for the administration of total parenteral nutrition over a 1-year period, the overall complication rate was 12.5 per cent (14.7 complications per 1000 catheter-days) and the catheter-related sepsis rate 4.4 per cent (5.2 per 1000 catheter-days). The probability of development of catheter-related sepsis did not increase with the duration of catheterization. There were no differences in the rate of complications associated with 427 catheters changed by replacement at a new site compared with 159 lines changed over a guidewire. These data support the use of multilumen central venous catheters for the administration of total parenteral nutrition. They suggest that a routine weekly change of line is unnecessary; catheters should be changed only on the development of a complication. When it is required, a catheter should be changed by replacement over a guidewire.

Vascular access devices: perspectives on designs, complications, and management

The use of vascular access devices in hospitalized and home care patients has expanded rapidly in the past decade. New designs, materials, insertion techniques, and protocols for care related to vascular access devices have emerged. Complications associated with them, however, have remained a persistent problem. Septicemia, thrombosis, and occlusion are three of the more serious complications that can lead to the need for removal of the device. These complications are reviewed and areas for future research are identified.