The impact of needleless connector device design on central venous catheter occlusion in children: a prospective, controlled trial

Needle-free connectors to prevent central venous catheter occlusion at a tertiary cardiac center: A prospective before and after intervention study

OBJECTIVES

To evaluate the effectiveness of needle-free connectors to maintain Central Venous Catheter-CVC patency.

BACKGROUND

Loss of patency is a common complication associated with CVC. For patients, this can be stressful and painful, and can result in a delay in infusion therapy. Pressure-activated anti-reflux needle-free connectors are one of the most modern devices; however, no studies have compared this connector with the open-system three-way stopcock in terms of the incidence of CVC occlusion.

METHODS

This study is a prospective before and after intervention study. From March to August 2018, an observation phase was conducted with the three-way stopcock as the standard central venous catheter hub and closure system (phase 1). After implementation of needle-free connectors (phase 2), post-intervention observations were made from September 2019 to January 2020 (phase 3).

RESULTS

Of 199 CVCs analyzed, 41.2% (40/97) occluded in at least one lumen in the first phase, and 13.7% (14/102) occluded after introducing the technological device, absolute risk reduction 27.5% (95% confidence interval 15.6%-39.4%). The lumens supported by needle-free connectors showed a higher probability of maintaining patency compared with three-way stopcocks. No differences were observed in the rate of infection.

CONCLUSIONS

Pressure-activated anti-reflux needle-free connectors are effective and safe devices suitable for the management of vascular access in cardiac patient care. Staff training, even on apparently simple devices, is essential to avoid the risk of infection.

Minimising Blood Stream Infection: Developing New Materials for Intravascular Catheters

Catheter related blood stream infection is an ever present hazard for those patients requiring venous access and particularly for those requiring long term medication. The implementation of more rigorous care bundles and greater adherence to aseptic techniques have yielded substantial reductions in infection rates but the latter is still far from acceptable and continues to place a heavy burden on patients and healthcare providers. While advances in engineering design and the arrival of functional materials hold considerable promise for the development of a new generation of catheters, many challenges remain. The aim of this review is to identify the issues that presently impact catheter performance and provide a critical evaluation of the design considerations that are emerging in the pursuit of these new catheter systems.

Positive-pressure needleless connectors did not increase rates of catheter hub colonization respecting the use of neutral-pressure needleless connectors in a prospective randomized trial

INTRODUCTION

The aim of this study was to compare the colonization rates of central venous catheter (CVC) and arterial catheter (ArtC) hubs fitted with two types of needleless connectors (NCs).

METHODS

We designed a prospective randomized study to compare rates of catheter hub colonization of CVC and ArtC hubs fitted with two types of needleless connectors: neutral-pressure NCs (NP-NCs) and positive-pressure NCs (PP-NCs) in critically ill patients. All NCs were replaced every 7 days of use.

RESULTS

We obtained 326 cultures from 146 catheters (81 CVC and 65 ArtC) in 70 patients. The total cumulative days of risk were 1250 catheter-days. Global swab cultures were positive in NP-NCs in 29/198 (14.6%) versus 17/128 (13.3%) in PP-NCs during catheter use. We did not observe any cases of CRBSI.

CONCLUSIONS

In our experience, the use of PP-NCs did not result in significantly more frequent hub colonization with respect to NP-NCs.

Quantitative assessment of reflux in commercially available needle-free IV connectors

INTRODUCTION

Blood reflux is caused by changes in pressure within intravascular catheters upon connection or disconnection of a syringe or intravenous tubing from a needle-free connector (NFC). Changes in pressure, differing with each brand of NFC, may result in fluid movement and blood reflux that can contribute to intraluminal catheter occlusions and increase the potential for central-line associated bloodstream infections (CLABSI).

METHODS

In this study, 14 NFC brands representing each of the four market-categories of NFCs were selected for evaluation of fluid movement occurring during connection and disconnection of a syringe. Study objectives were to 1) theoretically estimate amount of blood reflux volume in microliters (μL) permitted by each NFC based on exact component measurements, and 2) experimentally measure NFC volume of fluid movement for disconnection reflux of negative, neutral and anti-reflux NFC and fluid movement for connection reflux of positive displacement NFC.

RESULTS

The results demonstrated fluid movement/reflux volumes of 9.73 μL to 50.34 μL for negative displacement, 3.60 μL to 10.80 μL for neutral displacement, and 0.02 μL to 1.73 μL for pressure-activated anti-reflux NFC. Separate experiment was performed measuring connection reflux of 18.23 μL to 38.83 μL for positive displacement NFC connectors.

CONCLUSIONS

This study revealed significant differences in reflux volumes for fluid displacement based on NFC design. While more research is needed on effects of blood reflux in catheters and NFCs, results highlight the need to consider NFCs based on performance of individual connector designs, rather than manufacturer designation of positive, negative and neutral marketing categories for NFCs without anti-reflux mechanisms.

Visual Sensor for Sterilization of Polymer Fixtures Using Embedded Mesoporous Silicon Photonic Crystals

A porous photonic crystal is integrated with a plastic medical fixture (IV connector hub) to provide a visual colorimetric sensor to indicate the presence or absence of alcohol used to sterilize the fixture. The photonic crystal is prepared in porous silicon (pSi) by electrochemical anodization of single crystal silicon, and the porosity and the stop band of the material is engineered such that the integrated device visibly changes color (green to red or blue to green) when infiltrated with alcohol. Two types of self-reporting devices are prepared and their performance compared: the first type involves heat-assisted fusion of a freestanding pSi photonic crystal to the connector end of a preformed polycarbonate hub, forming a composite where the unfilled portion of the pSi film acts as the sensor; the second involves generation of an all-polymer replica of the pSi photonic crystal by complete thermal infiltration of the pSi film and subsequent chemical dissolution of the pSi portion. Both types of sensors visibly change color when wetted with alcohol, and the color reverts to the original upon evaporation of the liquid. The sensor performance is verified using E. coli-infected samples.

Prospective observational study on central line-associated bloodstream infections and central venous catheter occlusions using a negative displacement connector with an alcohol disinfecting cap

BACKGROUND

Major complications of central venous catheter (CVC) use include bloodstream infection and occlusion. We performed a prospective, observational study to determine the rate of central line-associated bloodstream infection (CLABSI) and CVC occlusion using a negative displacement connector with an alcohol disinfecting cap.

METHODS

Patients were followed from the time of CVC insertion through 2 days after removal, at the time of hospital discharge if there was no documentation of removal, or 90 days after the insertion of the CVC if it was not removed. CLABSI was defined using National Healthcare Safety Network criteria. Data for evidence of lumen occlusions were extracted from the electronic health record. Direct observations were performed to assess adherence to hospital policy regarding CVC insertion practice.

RESULTS

A total of 2,512 catheters from 2,264 patients were enrolled for this study. There were 21 CLABSIs (0.84%; 95% confidence interval [CI], 0.48%-1.19%; 0.62 per 1,000 line days) and 378 occlusions (15.05%; 95% CI, 13.65%-16.45%; 11.23 per 1,000 line days). Eighty-five direct observations demonstrated insertion protocol adherence in 881 of 925 (95.24%; 95% CI, 93.87%-96.61%) measured criteria.

CONCLUSIONS

Lines placed following a standardized protocol using a negative displacement connector with an alcohol cap have low rates of infection compared with historically published findings. We also established that the occlusion rate is >15-fold the CLABSI rate.

In Vitro Evaluation of Fluid Reflux after Flushing Different Types of Needleless Connectors

Purpose

To evaluate fluid reflux, when disconnecting syringe, for different needleless connectors.

Materials

Nine connectors were tested; 540 measurements were carried out.

Results

The connectors tested showed very different performances, about reflux, on disconnection of the syringe used for flushing. The calculated reflux volumes are: Max Zero® - BD: 6.90 (±2.47) mm3; MicroClave Clear® - ICU Medical: 6.14 (±1.46) mm3; Bionecteur® - Vygon: 1.24(±0.73) mm3; Neutron® - ICU Medical: 0.12 (±0.15) mm3; SmartSite® Carefusion: 33.51 (±11.50) mm3; Safe Plus® - Cremascoli: 23.54 (±3.56) mm3; NeutraClear® - Cair: 9.36 (±1.87) mm3; NeutroX® - Cair: 0.33 (±0.31) mm3; Dasa® BTC: 2.38 (±1.67) mm3. Differences between investigated devices were statistically significant (p<0.001).

Discussion

It is difficult to establish the best quality-price ratio for needleless connectors. It is important to consider several variable factors: continuous or discontinuous infusion, catheter type, usage environment and caliber of catheter used. It would therefore be useful to have an indication of the intraluminal space potentially affected by blood reflux in relation to a specific device.

Conclusions

Needleless connector is one of the main factors involved in keeping catheter patency. It is important to perform the best choice among the connectors available. An empirical reflux measurement, relative to the needleless connector and the catheter in use, can be obtained using an 18G cannula.

The Influence of a Novel Needleless Valve on Central Venous Catheter Occlusions in Pediatric Patients

Background: Although it is common for central line catheters to develop a thrombotic occlusion, pediatric patients are at especially high risk of occlusion due to smaller vessels, smaller-gauge catheters, and slower rates of infusion. Mitigating catheter occlusions is costly, requiring tissue plasminogen activator, supplies, and nursing time. Our facility tested a novel neutral displacement needle-free valve designed to reduce occlusion.

Methodology: The organization determined a baseline occlusion rate for Hickman/Broviac catheters, in our 38-bed inpatient hematology/oncology department and our outpatient hematology/oncology clinic from August 2010 through October 2010. In 2011, a premarket test of the Neutron device (ICU Medical, San Clemente, CA) was conducted on the units. Based on the positive trial results, it was decided to implement the device housewide in December 2012.

Results: A comparison of baseline central line complete occlusion rates from August to October 2010 with Neutron trial data from July to October 2011. This pilot project demonstrated a 74.3% reduction (from a rate of 3.82 to a rate of 0.98) in all hematology/oncology department Hickman and Broviac complete catheter occlusions. Subsequently, comparing 5 months of housewide occlusion data from June through October 2012 to 2013, complete occlusions fell by 32.1% (from a rate of 1.56 to a rate of 1.06).

Conclusions: The use of the Neutron needle-free catheter patency device was associated with a reduction in complete occlusions. The corresponding reduction in treatment delays, nursing time spent managing occluded catheters, and fewer needlesticks to patients likely translates to financial benefit for the organization and improved patient and family satisfaction.

Heparin versus 0.9% sodium chloride intermittent flushing for the prevention of occlusion in long term central venous catheters in infants and children

BACKGROUND

Guidelines and clinical practice for the prevention of complications associated with central venous catheters (CVC) around the world vary greatly. Most institutions recommend the use of heparin to prevent occlusion, however there is debate regarding the need for heparin and evidence to suggest 0.9% sodium chloride (normal saline) may be as effective. The use of heparin is not without risk, may be unnecessary and is also associated with increased cost.

OBJECTIVES

To assess the clinical effects (benefits and harms) of intermittent flushing of heparin versus normal saline to prevent occlusion in long term central venous catheters in infants and children.

SEARCH METHODS

The Cochrane Vascular Trials Search Co-ordinator searched the Specialised Register (last searched April 2015) and the Cochrane Register of Studies (Issue 3, 2015). We also searched the reference lists of retrieved trials.

SELECTION CRITERIA

Randomised controlled trials that compared the efficacy of normal saline with heparin to prevent occlusion of long term CVCs in infants and children aged up to 18 years of age were included. We excluded temporary CVCs and peripherally inserted central catheters (PICC).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial inclusion criteria, trial quality and extracted data. Rate ratios were calculated for two outcome measures - occlusion of the CVC and central line-associated blood stream infection. Other outcome measures included duration of catheter placement, inability to withdraw blood from the catheter, use of urokinase or recombinant tissue plasminogen, incidence of removal or re-insertion of the catheter, or both, and other CVC-related complications such as dislocation of CVCs, other CVC site infections and thrombosis.

MAIN RESULTS

Three trials with a total of 245 participants were included in this review. The three trials directly compared the use of normal saline and heparin, however, between studies, all used different protocols for the standard and experimental arms with different concentrations of heparin and different frequency of flushes reported. In addition, not all studies reported on all outcomes. The quality of the evidence ranged from low to very low because there was no blinding, heterogeneity and inconsistency between studies was high and the confidence intervals were wide. CVC occlusion was assessed in all three trials (243 participants). We were able to pool the results of two trials for the outcomes of CVC occlusion and CVC-associated blood stream infection. The estimated rate ratio for CVC occlusion per 1000 catheter days between the normal saline and heparin group was 0.75 (95% CI 0.10 to 5.51, two studies, 229 participants, very low quality evidence). The estimated rate ratio for CVC-associated blood stream infection was 1.48 (95% CI 0.24 to 9.37, two studies, 231 participants; low quality evidence). The duration of catheter placement was reported to be similar between the two study arms, in one study (203 participants).

AUTHORS' CONCLUSIONS

The review found that there was not enough evidence to determine the effects of intermittent flushing of heparin versus normal saline to prevent occlusion in long term central venous catheters in infants and children. Ultimately, if this evidence were available, the development of evidenced-based clinical practice guidelines and consistency of practice would be facilitated.

Disinfection of Needleless Connector Hubs: Clinical Evidence Systematic Review

Background. Needleless connectors (NC) are used on virtually all intravascular devices, providing an easy access point for infusion connection. Colonization of NC is considered the cause of 50% of postinsertion catheter-related infections. Breaks in aseptic technique, from failure to disinfect, result in contamination and subsequent biofilm formation within NC and catheters increasing the potential for infection of central and peripheral catheters. Methods. This systematic review evaluated 140 studies and 34 abstracts on NC disinfection practices, the impact of hub contamination on infection, and measures of education and compliance. Results. The greatest risk for contamination of the catheter after insertion is the NC with 33-45% contaminated, and compliance with disinfection as low as 10%. The optimal technique or disinfection time has not been identified, although scrubbing with 70% alcohol for 5-60 seconds is recommended. Studies have reported statistically significant results in infection reduction when passive alcohol disinfection caps are used (48-86% reduction). Clinical Implications. It is critical for healthcare facilities and clinicians to take responsibility for compliance with basic principles of asepsis compliance, to involve frontline staff in strategies, to facilitate education that promotes understanding of the consequences of failure, and to comply with the standard of care for hub disinfection.

Heparin versus 0.9% sodium chloride intermittent flushing for prevention of occlusion in central venous catheters in adults

BACKGROUND

Heparin intermittent flushing is a standard practice in the maintenance of patency in central venous catheters. However, we could find no systematic review examining its effectiveness and safety.

OBJECTIVES

To assess the effectiveness of intermittent flushing with heparin versus 0.9% sodium chloride (normal saline) solution in adults with central venous catheters in terms of prevention of occlusion and overall benefits versus harms.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched December 2013) and the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 11). Searches were also carried out in MEDLINE, EMBASE, CINAHL and clinical trials databases (December 2013).

SELECTION CRITERIA

Randomised controlled trials (RCTs) in adults 18 years of age and older with a central venous catheter (CVC) in which intermittent flushing with heparin (any dose with or without other drugs) was compared with 0.9% normal saline were included. No restriction on language was applied.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed trial quality and extracted data. Trial authors were contacted to retrieve additional information, when necessary.

MAIN RESULTS

Six eligible studies with a total of 1433 participants were included. The heparin concentrations used in these studies were very different (10-5000 IU/mL), and follow-up varied from 20 days to 180 days. The overall risk of bias in the studies was low. The quality of the evidence ranged from very low to moderate for the main outcomes (occlusion of CVC, duration of catheter patency, CVC-related sepsis, mortality and haemorrhage at any site).Combined findings from three trials in which the unit of analysis was the catheter suggest that heparin was associated with reduced CVC occlusion rates (risk ratio (RR) 0.53, 95% confidence interval (CI) 0.29 to 0.94). However, no clear evidence of a similar effect was found when the results of two studies in which the unit of analysis was the participant were combined (RR 0.21, 95% CI 0.03 to 1.70), nor when findings were derived from one study, which considered total line accesses (RR 1.08, 95% CI 0.84 to 1.40). Furthermore, results for other estimated effects were found to be imprecise and compatible with benefit and harm: catheter duration in days (mean difference (MD) 0.41, 95% CI -1.29 to 2.12), CVC-related thrombosis (RR 1.22, 95% CI 0.74 to 1.99), CVC-related sepsis (RR 1.02, 95% CI 0.34 to 3.03), mortality (RR 0.77, 95% CI 0.45 to 1.32) and haemorrhage at any site (RR 1.37, 95% CI 0.49 to 3.85).

AUTHORS' CONCLUSIONS

We found no conclusive evidence of important differences when heparin intermittent flushing was compared with 0.9% normal saline flushing for central venous catheter maintenance in terms of efficacy or safety. As heparin is more expensive than normal saline, our findings challenge its continued use in CVC flushing outside the context of clinical trials.

Management of central venous catheters in pediatric onco-hematology using 0.9% sodium chloride and positive-pressure-valve needleless connector

PURPOSE

To describe, in a sample of pediatric onco-hematological patients, the rate of occlusions in unused central venous catheters (CVC) flushed once a week with a 0.9% sodium chloride solution through a positive-pressure-valve needleless connector.

METHOD

Retrospective cohort study. Subjects aged 0-17 years were identified through a manual search in medical and nursing records and were observed for two years or until the occurrence of one of the following events: start or resume of continuous infusion; CVC removal; death. The primary study outcome was the frequency of CVC occlusion (partial or complete).

RESULTS

Fifty-one patients were identified (median age 6 years). The median duration of follow-up was 169 days (IQR 111-305). During the follow up period, 14 patients (27%) had one CVC occlusion, in 2 cases (4%) the occlusion was complete, in 12 (23%) partial. All the occlusions were solved without the need for catheter removal. The lumen diameter ≤ 4.2 vs > 4.2 French showed a statistically significant association with occlusion at multivariate analysis (OR 4.0; 95% CI 1.1-14.7).

CONCLUSIONS

Our findings are reassuring with respect to the management of the CVC using the adopted protocol. The study provides useful information for patient care, by verifying the performance of the adopted CVC management protocol and by identifying critical areas for nursing care.

Clinical efficacy and safety of Securflux®, an anti-reflux device for intravenous infusion

PURPOSE

Catheter obstruction or patency inhibition of the venous access cannula is a frequently experienced problem in patients to whom intravenous (IV) solutions are administered. In this study we assessed the efficacy and safety of Securflux® a disposable device with a back-check valve to prevent reflux in IV infusion sets.

METHODS

A total of 177 adult patients requiring IV medication for at least 24 hours duration were randomized into two groups: with and without the use of Securflux®. Assessments were performed the 10 days after catheter insertion, over three daily visits. The incidence of the onset of reflux (visual/non-visual) and the consequences of reflux for both the patient and healthcare staff were assessed.

RESULTS

There were 4577 follow-up (study) visits (53.4% in patients with Securflux® and 46.6% without Securflux®). Venous reflux was observed in 14.2% of all visits, more frequently without Securflux® (21.3% vs. 8.1%; P<.05). Reflux was mostly visual without Securflux® (7.6% vs. 0.7%) and non-visual with Securflux® (13.6% vs. 7.3%). The onset of venous reflux carried more consequences, such as inhibition of the line and patient discomfort, in the infusions without Securflux® (81.1% vs. 73.5% of the visits; P<.05). There were no safety concerns related to Securflux®.

CONCLUSIONS

Securflux® is effective, safe and useful for the prevention of venous reflux onset in patients administered IV medication.

The effects of needleless connectors on catheter-related bloodstream infections

Needleless connectors, including the standard split septum and the luer-activated mechanical valve connectors, have been introduced into clinical practice to eliminate the risk of needlestick injuries by avoiding the use of needles when accessing the intravascular catheters. Negative and positive displacement mechanical valves have been associated with increased rates of catheter-related bloodstream infections as compared with split septum connectors. Based on available data, split septum connectors should be preferentially used instead of mechanical valves. Adequate disinfection by scrubbing the access port preferably with chlorhexidine is recommended to minimize the risk of catheter microbial contamination along with proper infection control practices. Large prospective randomized clinical trials are needed to evaluate further the possible causes and effects of different types of mechanical valve needleless connectors on bloodstream infections.

Heparin flushing and other interventions to maintain patency of central venous catheters: a systematic review

AIM

This paper is a report of a review to assess clinical studies comparing the effectiveness of different means of maintaining central venous catheter patency.

BACKGROUND

Flushing with heparin is a routine part of central venous catheter maintenance, but it presents risks, including heparin-induced thrombocytopenia. Other techniques used to prevent occlusion of catheters include saline flushes, heparin-bonded catheters and pressure caps.

DATA SOURCES

A search was conducted using the MEDLINE, CINAHL, EMBASE, Cochrane, National Guideline Clearinghouse and University Healthsystem Consortium databases.

METHODS

A systematic review of effectiveness was conducted, using GRADE criteria to assess the strength of evidence for each intervention. The review period covered 1982 or earlier to January 2008.

RESULTS

There is weak evidence that heparin flushing reduces occlusion of catheters, but no evidence that it reduces bloodstream infections. Results from clinical trials of pressure caps are inconsistent regarding their ability to maintain catheter patency, but provide moderate evidence that at least some varieties of caps are associated with increased bloodstream infections.

CONCLUSION

The evidence base on heparin flushing and other interventions to prevent catheter occlusion is small, and published studies are of low quality. There is insufficient evidence on which to conclude that flushing catheters with heparin is more effective than flushing with saline solution.

Stopcock lumen contamination does not reflect the full burden of bacterial intravenous tubing contamination: analysis using a novel injection port

BACKGROUND

Prior clinical studies have used injection port lumen culture as a marker of intravenous (IV) fluid system contamination. We hypothesized that culturing injected saline (effluent) is a more sensitive method of detecting IV fluid system bacterial contamination than lumen culture. To test this hypothesis, we compared the incidence of lumen contamination with effluent contamination in a simulated setting. We also measured the effect of a novel injection port protective device (Port Guide; Matrix Tooling, Inc, Wood Dale, IL) on contamination.

METHODS

In this ex vivo study, 33 providers performed 5 injections of 1 mL sterile saline into each of 4 injection port designs: (1) stopcock, (2) stopcock with Port Guide, (3) stopcock with disinfectable needleless closed connector (DNCC), and (4) stopcock with DNCC and Port Guide. The primary outcome was the rate of effluent contamination with simultaneously contaminated injection port lumen.

RESULTS

Bacterial organisms were recovered from the effluent in 17 of the 132 injection ports evaluated. Of those 17 injection ports with contaminated effluent, 4 injection port lumens were simultaneously contaminated (24%). Additionally, use of the stopcock with Port Guide significantly reduced effluent contamination.

CONCLUSION

Effluent culture is a more sensitive marker of IV fluid system contamination than injection port lumen culture. A novel protective device on the stopcock (Port Guide) significantly reduced IV fluid system bacterial contamination.

Nurses’ knowledge of intravenous connectors

No published studies assess the knowledge of staff nurses regarding intravenous connectors, yet connectors remain a primary cause of infection and mortality. Anonymous survey (N = 100) in acute hospitals revealed 78% of nurses were uninformed about different connector types and their different care and 43% could not name two complications of connectors. No significant relationship was found between education (r = 0.121, p < 0.05) or nursing specialty (r =-0.059, p < 0.05) and identifying types of connectors. Sixty-four per cent were involved in 5—6 hours of intravenous therapy and maintenance per 12-hour shift, hence connector care is significant. Education about connectors has implications for nursing associated with catheter-related bloodstream infections, occlusion and thrombosis. The Centers for Disease Control includes catheter-related bloodstream infections as a worldwide priority. This study identified a significant need for further nursing education and research regarding the types, maintenance and care of intravenous connectors.

[Safety and quality in intensive care medicine]

The safety and quality care are two attributes of the health care that are closely intertwined. Quality is a feature of the system that delivers health care, thereby improving it, we need a proper reorganization teamwork. Measurements of quality are intended to assess whether the process of health care reaches the desired objectives, while avoiding the processes that predispose to harm the patient. The critically ill patients are vulnerable to medical errors, and may experience side effects preventable, often associated with: medications, mechanical ventilation, and intravascular devices. The evidence currently available suggest that the safety and quality of care can be improved. In this article presents some of the strategies and interventions developed to optimize the processes of care in critically ill patients, and improve the safety culture in the ICU.

Impact of the Positive Pressure Valve on Vascular Access Device Occlusions and Bloodstream Infections

Background/Purpose: The use of needleless positive pressure connector valves (PPVs) on venous access devices (VADs) has been shown to have possible benefits in decreasing VAD occlusion rates. Catheter-related bloodstream infection (CRBSI) rates, however, have been variable. With this potential for improving patient outcomes, decreasing costs, and facilitating nursing care and catheter management, the use of PPV devices becomes both advantageous and desirable.

Methodology: This was a randomized, prospective, parallel clinical study of 160 medical and surgical step-down unit patients requiring parenteral therapies. Patients were equally randomized to two study groups to assess the impact on occlusion and CRBSI rates, using a PPV versus a standard cap without PPV. VADs included both peripherally inserted catheters (PICCs) and midlines.

Results: Seven VAD occlusions occurred; six in the experimental group, one in the control group (p = 0.43). Also, two CRBSIs occurred in the experimental group, with none in the control group (p = 0.497). All incidents occurred in doublelumen PICCs. The lack of statistical difference between the two groups for occlusions and CRBSIs indicates that the use of PPVs had no impact in preventing such outcomes. However, it was observed that the number of double-lumen PICCs and their dwelling time in the experimental group was significantly higher (p = 0.003).

Conclusion: There was no difference in the rate of catheter occlusions or CRBSIs when using PPVs or standard caps. We consider that the study outcomes may be due to the study's small sample size, and we speculate that longer dwell time of double lumen catheters may have contributed to these outcomes. These observations deserve further investigation. However, the use of PPVs may still be advantageous from a nursing process perspective.

Prospective, randomized trial of two different modalities of flushing central venous catheters in pediatric patients with cancer

PURPOSE

There are limited prospective data on whether the method of flushing affects the complication rate of tunnelled central venous catheters (CVCs).

PATIENTS AND METHODS

During a 25-month period, 203 pediatric patients who had newly placed Broviac-Hickman CVCs were randomly assigned to standard flushing with heparin solution or to experimental flushing with normal saline via a positive-pressure cap.

RESULTS

Two hundred twenty-one complications were recorded among 75,249 CVC-days (2.94 per 1,000 CVC-days). A higher incidence of CVC occlusion (83 v 41 episodes; P = .0002) and bacteremia (24 v 9; P = .01) were found in the experimental arm. The cumulative probability of developing at least one CVC complication was higher in the experimental arm than in the standard arm (65.1% [95% CI, 55% to 75%] v 43.8% [95% CI, 34% to 54%], respectively; P = .01). No difference was found in either the cause or the frequency of premature removal of CVCs between the two study arms. After a median follow-up of 360 days (range, 4 to 1,073), CVC survival was similar: 77% (95% CI, 66% to 84%) for the experimental arm and 69% (95% CI, 53% to 80%) for the standard arm (P = .7). The factors associated with the occurrence of CVC complication were a diagnosis of leukemia/lymphoma, double-lumen CVC, and experimental flushing. The only factor significantly associated with premature removal of a CVC was a diagnosis of leukemia/lymphoma (hazard rate, 2.3; 95% CI, 1.1 to 4.7).

CONCLUSION

An increased complication rate was found with normal saline flushing, but additional investigation is warranted to clarify whether it is related to saline use or to once-a-week flushing.

Clinical use of disinfectable needle-free connectors

BACKGROUND

In 1992, the United States Food and Drug Administration required health care services to adopt needle-free devices to prevent health care workers' exposure to bloodborne pathogens resulting from needlestick injuries, and several systems of disinfectable needle-free connectors (DNC) were introduced.

STUDIES

MICROBIAL COLONIZATION: Experimental studies showed that DNCs designed with a split septum (SS-DNCs) and mechanical valve systems (MLV-DNC) prevented endoluminal colonization as effectively as needles or conventional caps. A comparison of the microbiologic barrier effect of SS-DNCs, MLV-DNCs, and passive positive-pressure (PPV)-DNCs found that PPV-DNCs were least effective in providing protection under experimental conditions of poor handling practices and high microorganism concentrations. PREVENTION OF CATHETER-RELATED BLOODSTREAM INFECTIONS: Some randomized trials show a positive or neutral effect of DNC use on the prevention of catheter-related bloodstream infections (CR-BSIs); however, some investigators have reported outbreaks of CR-BSIs following the introductions of DNCs that could be related to noncompliance with DNC handling recommendations or the use of PPV-DNCs.

CONCLUSION

Strategies focused in the implication of the nurse staff in CRBSI surveillance increase compliance with DNC handling recommendations and minimize the risk of developing a CR-BSI. DNCs can be used safely if staff complies with recommendations for use.

Safety of positive-pressure valve connectors in arterial catheters inserted into critically ill patients

Needleless valve connectors were introduced to avoid needlestick injuries in healthcare workers but some concerns exist about their microbiological safety. A randomised controlled trial was performed to assess hub colonisation affecting positive-pressure valve connectors (PPVCs) compared to conventional caps used for radial arterial catheters inserted into critically ill patients. Patients were randomly assigned either to the PPVC (Smartsite Plus positive bolus valve) or to the conventional cap group. Only catheters inserted for >24h were analysed. Of 100 consecutive arterial lines, 80 were inserted for >24h (mean insertion duration 5.8 days), 41 in the PPVC group and 39 in the conventional cap group. Catheter hubs were colonised in eight cases in the control group (20.5%) and in one case in the PPVC group (2.4%). Hub colonisation was caused by coagulase-negative staphylococci in all cases. No attributable bacteraemia was observed. In multivariate analysis, PPVC (odds ratio: 0.09; 95% confidence interval: 0.1-0.79; P=0.03) and use of the line for continuous haemodynamic monitoring (0.16; 0.03-0.89; P=0.037) were independently associated with a lower incidence of hub colonisation.

The life-threatening hemodialysis catheter heparin lock caused bleeding in a child after peritoneal catheter removal

Hemodialysis catheter patency is regularly maintained by high-concentration heparin filling, according to manufacturer's recommendation. Surprisingly, there are only few reports on serious bleeding complications in children on dialysis. A case of serious, life-threatening hemorrhage in a child after tunneled peritoneal catheter removal because of hemodialysis catheter heparin lock flushing is described. Discussion of the literature data is presented. Further investigations are needed to develop the guidelines for pediatric dialysis catheter care, including the optimal concentration for heparin lock as the possible heparin alternatives, but until that moment, previously suggested guidelines to prevent hemorrhagic complications in dialyzed children should be emphasized.

Outbreak of bloodstream infection temporally associated with the use of an intravascular needleless valve

BACKGROUND

Needleless intravascular catheter connector valves have been introduced into clinical practice to minimize the risk of needlestick injury. However, infection-control risks associated with these valves may be underappreciated. In March 2005, a dramatic increase in bloodstream infections was noted in multiple patient care units of a hospital in temporal association with the introduction of a needleless valve into use.

METHODS

Surveillance for primary bloodstream infection was conducted using standard methods throughout the hospital. Blood culture contamination rates were monitored. Cultures were performed using samples obtained from intravascular catheter connector valves.

RESULTS

The relative risk of bloodstream infection for the time period in which the suspect connector valve was in use, compared with baseline, was 2.79 (95% confidence interval, 2.27-3.43). In critical care units, the rate of primary bloodstream infection increased with the introduction of the valve from 3.87 infections per 1000 catheter-days to 10.64 infections per 1000 catheter-days (P<.001), and it decreased to 5.59 infections per 1000 catheter-days (P=.02) in the 6 months following removal of the device from use. Similarly, in inpatient nursing units, the rate of bloodstream infection increased from 3.47 infections per 1000 catheter-days to 7.3 infections per 1000 catheter-days (P=.02) following introduction of the device, and it decreased to 2.88 infections per 1000 catheter-days (P=.57) following removal of the device from use. Similar events occurred in the cooperative care units. The rate of blood culture contamination did not substantially change over the course of the study. Of 37 valves that were subjected to microbiological sample testing, 24.3% yielded microbes, predominantly coagulase-negative staphylococci.

CONCLUSION

A significant association between primary bloodstream infection and a needleless connector valve was observed. Evaluation of needleless connector valves should include a thorough assessment of infection risks in prospective randomized trials prior to their introduction to the market.

Heparin Locking for Central Venous Catheters

Traditionally, heparin-lock solution has been used with all central venous catheters. The introduction of new technology calling for the elimination of heparin and the growing concerns about the use of heparin have caused many health care professionals to question its continued use for this purpose. This literature review attempts to answer the most common questions using available research; however, there continues to be more questions than answers. At present, it appears that some farm of anticoagulant will produce more patent catheters, and heparin-lock solution is the only product commercially available. This situation drives the need for a careful assessment of patients' needs prior to abandoning the use of heparin.