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

The use of Hub Devices to reduce catheter-related infections in dialysis patients: A narrative review

INTRODUCTION

Catheter-related bloodstream infections are among the most critical issues associated with central venous catheters used for dialysis treatment. To reduce the incidence of this life-threatening complication, various strategies have been developed. Among these, Hub Devices have been introduced in clinical practice to prevent microbial growth at the hub of the catheter.

METHODS

A review was conducted to assess the effectiveness of Hub Devices in reducing bloodstream infections in central venous catheters for dialysis, compared to solid caps. The review analyzed existing literature from three bibliographic databases (PubMed, Embase, and CINAHL) to provide evidence-based recommendations for clinical practice.

RESULTS

After a thorough review of the available data, it was found that out of the 873 records screened, only six trials met the inclusion criteria. Albeit the number of patients observed in these trials was more than 25,000, due to the differences in the mechanism of action of different Hub Devices and the lack of a standardized criterion to identify and measure the outcomes, it is difficult to draw a firm conclusion. It is worth noting, however, that in five out of six trials examined, the Hub Devices exhibited a protective effect when compared to solid caps.

CONCLUSIONS

The use of Hub Devices appears to be associated with a reduction in catheter-related bloodstream infections in the central venous catheter dialysis population. However, the Hub Devices show interesting results that should be investigated with further well-designed prospective studies.

Effect of vertical pump position on start-up fluid delivery of syringe pumps used for microinfusion

BACKGROUND

Connection and opening a syringe infusion pump to a central venous line can lead to acute anterograde or retrograde fluid shifts depending on the level of central venous pressure. This may lead to bolus events or to prolonged lag times of intravenous drug delivery, being particularly relevant when administering vasoactive or inotropic drugs in critically ill patients using microinfusion. The aim of this study was to assess the effect of syringe pump positioning at different vertical heights on start-up fluid delivery before versus after purging and connection the pump to the central venous catheter.

METHODS

This in vitro study measured ante- and retrograde infusion volumes delivered to the central venous line after starting the syringe pump at a set infusion rate of 1 mL/h. In setup one, the pump was first positioned to vertical levels of +43 cm or -43 cm and then purged and connected to a central venous catheter. In setup two, the pump was first purged and connected at zero level and secondarily positioned to a vertical level of +43 cm or -43 cm. Central venous pressure was adjusted to 10 mmHg in both setups.

RESULTS

Positioning of the pump prior to purging and connection to the central venous catheter resulted in a better start-up performance with delivered fluid closer to programmed and expected infusion volumes when compared to the pump first purged, connected, and then positioned. Significant backflow volumes were observed with the pump purged and connected first and then positioned below zero level. No backflow was measured with the pump positioned first below zero level and then purged and connected.

CONCLUSIONS

Syringe infusion pump assemblies should be positioned prior to purging and connection to a central venous catheter line when starting a new drug, particularly when administering highly concentrated vasoactive or inotropic drugs delivered at low flow rates.

Assessment of Reflux From Needleless Connectors: Blinded Comparison of Category Designation to Benchtop Function Using a Venous Simulator

Needleless connectors (NCs) for vascular access have limited needlestick injuries, but complications including occlusion, thrombosis, and infections have increased despite reduced needlestick injuries. These complications relate to the ability of an NC design to limit volume fluctuations that can lead to fluid reflux with potential for microbial contamination. Different NC designs requiring specific usage protocols and training, a lack of clarity in NC function relative to manufacturer-designated categories, and confounding results from a limited number of studies comparing different NCs have resulted in confusion, ultimately leading to complications from undesirable fluid movement within the vascular access. The authors therefore quantified the magnitude of reflux with current commercially available NCs using a venous stimulator. Thirteen blinded NC designs spanning the categories of negative and positive displacement, neutral, and antireflux were tested to quantify fluid movement upon disconnection and reconnection from a representative intravenous pressure (3 NCs per design; 10 trials per NC). Trials for each NC tested followed consistent displacement trends leading to tight error bars. Blinded NCs were then characterized according to their function and compared with their category designation after unblinding. All positive and negative NCs functioned in a manner consistent with their respective category designations. Conversely, all NCs categorized as neutral actually functioned with negative displacement (ie, reflux upon disconnection; 4/5 NCs) or positive displacement (1/5 NCs). Only NCs classified as antireflux functioned as neutral, which was confirmed in a blinded bidirectional flow test. These results suggest that the neutral NC-marketed category may be confusing to users unless the particular NC design has an integrated antireflux component.

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.

Incidence, risk factors and medical cost of peripheral intravenous catheter-related complications in hospitalised adult patients

BACKGROUND

Peripheral intravenous catheters (PVCs) are widely used vascular access devices for infusion therapy; however, they are associated with relatively high failure rates. This study aimed to identify the incidence, risk factors and medical costs of PVC-induced complications in adult hospitalised adult patients in China.

METHODS

An observational, prospective study on 1069 patients lasting 5 months was conducted at a tertiary teaching hospital.

RESULTS

Infiltration ranked first among PVC complications with an incidence of 17.8%, followed by occlusion (10.8%) and phlebitis (10.5%). Most complications in phlebitis (88.4%) and infiltration (93.7%) were Grade 1. Catheters left in for over 96 h did not show a higher incidence of complications. Patients from the surgical department were more susceptible to infiltration, phlebitis and occlusion. The 26 gauge (Ga) catheters decreased the risk of phlebitis and occlusion, whereas 24Ga catheters increased infiltration rates. Infusing irritant drugs increased phlebitis and infiltration rates. The presence of comorbidities and non-use of needleless connectors were associated with occlusion. Compared with forearm insertion, the risk of occlusion nearly doubled with the dorsum of the hand insertion and the risk of infiltration tripled with antecubital fossa insertion. Medical treatment costs for PVC complications ranged from 0.3 to 140.0 CNY.

CONCLUSIONS

Infiltration is the most common PVC-related adverse event. Clinically-indicated instead of routine replacement of catheters is safe. More efforts are warranted to improve nurses' adherence to recent guidelines in terms of insertion site selection and needleless connector utilisation to reduce medical costs associated with catheter replacement.

Changing the syringe pump: A challenging procedure in critically ill patients

INTRODUCTION

In the literature, the change of a syringe pump is described as a dangerous situation, especially in the case of vasoactive drug administration.

METHODS

Different variables have been studied (central venous pressure, pump displacement in relation to the patient position, utilization of a stopcock, or a neutral displacement needle-free connector between the syringe and the infusion tubing) to understand their influence on medication administration in terms of backflow or bolus creation when changing the syringe.

RESULTS

We performed 576 measurements with different combinations. With respect to all the observations, in comparison with "time zero," we found the following differences expressed in microliters: 0 (±1) at the plunger opening; 0 (±3) at the syringe extraction from the pump; 0 (±7) at the syringe disconnection from the infusion tubing; 0 (±11) at the syringe reconnection to the infusion tubing; 1 (±7) at the syringe insertion in the pump; 3 (±23) at the plunger closing; 8 (±33) at the stabilization at the maneuver end.

CONCLUSION

The syringe change can be a very critical moment given different influencing variables. Syringe pump position, displaced higher than the patient level, always generates a medication bolus that is higher at the lowering of the central venous pressure value. The presence of a neutral displacement needle-free connector reduces the incidence of boluses. When the pump is placed at the patient level, the presence of neutral displacement needle-free connector reduces the establishment of boluses, even in a central venous pressure of -5 mmHg simulations.

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.

Lean Six Sigma for Intravenous Therapy Optimization: A Hospital Use of Lean Thinking to Improve Occlusion Management

Background: Continual improvement is a necessary part of hospital culture. This occurs by identifying opportunities for improvement that influence efficiency while saving money.

Methodology: An investigation of intravenous device-related practices was performed by the nurses of the intravenous access team, pharmacy, and hospital operations at Hartford Hospital using Lean Six Sigma methodology. Central venous access device occlusion and tissue plasminogen activator variability was identified. Using observation, measurement of performance, and root cause analysis, the hospital's practices, policies, and equipment were evaluated for the process of occlusion management. The team utilized a Six Sigma strategy employing the elements define, measure, analyze, improve, and control, which is a disciplined, data-driven methodology that focuses on eliminating defects (waste). Interventions initiated based on the assessment performed by the team using the define, measure, analyze, improve, and control approach included replacement of negative displacement needleless connectors with antireflux needleless connectors and specialty team assessment before tissue plasminogen activator use.

Results: Over the course of the 26-month study, Hartford Hospital experienced a 69% total reduction in tissue plasminogen activator use representing a total 26-month savings of $107,315. Other cost savings were reflected in areas of flushing, flushing disposables, and in a decrease in needleless connector consumption. Central line-associated bloodstream rates fell 36% following the intervention as an unexpected secondary gain, resulting in further savings related to treating this nonreimbursable hospital-acquired condition.

Conclusions: This study examined the influence of using Lean Thinking and Six Sigma methodology as a tool in saving hospital money, resulting in better patient outcomes.