Needleless Connectors & Patency

Common language facilitates communication between professional and organisations, the translation of evidence into clinical practice, data sharing, and research. CNSA, eviQ and eviQ Education are leading vascular access management and education in cancer care in Australia utilizing common, contemporary terminology (Table 1).

Table 1: CVAD terminology

Needleless connectors (NC) are devices that are attached to a Central Venous Access Device (CVAD) catheter hub, extension tubing attached to a huber needle of a Totally Implantable Venous Access Device (TIVAD) or Peripheral Intravenous Cannula (PIVC). Needleless connectors facilitate intermittent access to an intravenous system without a needle (1) and ensure the intravenous system is a closed system (2). A closed system is associated with reduced CVAD related infections (3).

There is much confusion surrounding needleless connectors due to the different features and functions of the numerous products currently available. In this document, needleless connectors will be categorised according to their function when the syringe or administration set is disconnected: negative, positive, neutral, or anti-reflux. This means what occurs at the catheter or cannula tip with flow of the solution in relation to the potential for blood reflux when the syringe is disconnected. This is influenced by the disconnection – clamping sequence.

• Negative needleless connectors: there is a negative displacement at the catheter (CVAD) or cannula tip (PIVC) which allows for blood reflux back into the catheter or cannula tip on disconnection of a syringe or administration set. Therefore, to prevent blood reflux, the catheter or extension tubing (for Totally Implanted Venous Access Devices and Peripheral Intravenous Cannulas) should be clamped PRIOR to finishing the flush and disconnecting the syringe. This means the fluid is flowing out of the catheter when it is clamped and before blood can flow back in.
  
  For example: Q-Syte™, Safeflow®, SmartSite®,
• Positive needleless connectors: these devices contain a small volume of fluid that is pushed through the CVAD catheter or PIVC when a syringe or administration set is removed. So, there is a positive displacement of fluid out of the catheter or cannula. Therefore, the catheter or extension tubing (for TIVADs and PIVCs) should be clamped AFTER finishing the flush and disconnecting the syringe.
  
  For example: MaxPlus®, Ultrasite®, Caresite®, MaxZero™
• Neutral needleless connectors: these devices are designed with an internal mechanism which prevents blood reflux into the catheter or cannula tip on disconnection of a syringe or administration set. Therefore, a specific clamping sequence at the end of flushing or locking is not required.
  
  For example: Bionector®, MicroClave®, One-Link®, Kendal®, Nanoclave®
• Anti-reflux needleless connectors or bidirectional needleless connectors are devices that contain a pressure-sensitive internal mechanism which prevents blood reflux into the catheter or cannula tip when the flow of an infusion is stopped. Therefore, a specific clamping sequence is also not required. (1)
  
  For example: Neutron®, Nexus TKO-6P® 

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An important patient safety article discussed the complexity involved with the selection of the ‘best’ needleless connector and the design of these devices which plays a significant role in reducing healthcare-associated catheter-related bloodstream infection risk (4). Design also plays a role in reducing the risk of occlusion. Jarvis, 2010 discussed nine design elements of needleless connectors that should be considered when evaluating a device and recommendations which included:

1. Septum surface: is the external surface of the septum smooth to facilitate thorough disinfection?
2. Septum seal: is there a tight seal with zero or minimal gaps between the septum and housing to reduce the risk of contamination by biofilm?
3. Fluid pathway: is the pathway direct and straight through the NC to facilitate flushing and removal of debris and to reduce the area of internal surface for the development of biofilm?
4. Dead space: are there any dead spaces or pockets in the fluid pathway which cannot be reached by flushing solutions where biofilm can develop?
5. Internal mechanism: is the fluid pathway direct, not torturous and simple, preferably with no moving parts?
6. Clamping sequence: is a specific clamping sequence required? Preferably not but if so, ensure only one type of NC so the clamping sequence on disconnection is the same.
7. Visibility: is the housing transparent so any blood or contaminants can be seen?
8. Blood reflux: does the NC have a luer access mechanism with little or no blood reflux?
9. Flushing solution: can the NC be flushed and locked with sodium chloride only?

This document will identify current evidence and make recommendations using the above principles.

1.1 Summary of Evidence

Five studies discussed needleless connectors in the patients with cancer cohort including:

Adult:

• A quality improvement, sequential project over multiple sites included 600 Peripherally Inserted Central Catheters (PICCs) over 9702 catheter days and assessed the impact of introducing a bidirectional needleless connector on occlusion rates. There was poor quality baseline data (occlusion estimated at 5% with no definitive data) and after introduction of the new NC it was noted a partial occlusion rate of 1.4/1000 catheter days and complete occlusion rate of 0.4/1000 catheter days. The study also noted the use of heparinised saline and thrombolytic agents decreased, and the number of PICCs replaced due to occlusion also decreased. It was suggested that healthcare costs would be reduced (not completed in this study) due to a decrease use of heparin as sodium chloride was used for locking with the new NC, a reduced use of consumables, reduced use of thrombolytic agents and fewer PICC replaced. This study stated that pulsatile flushing technique is an important factor to clearing the CVAD and NC from blood and drug residues (5).

Paediatric:

• A pre-post, observational study of Tunnelled Cuffed-Centrally Inserted Central Catheters (tc-CICC), 7312 catheter days pre, during the trial period and post the introduction of a needleless connector with a bidirectional silicone needleless connector to investigate the impact on occlusion rates. The study noted a 74.3% reduction of complete occlusions in haematology oncology patient cohort so introduced the NC hospital wide with a 47.1% reduction. This was decreased further with compliance strategies to assist the entire organisation use the new NC (6).
• A retrospective, longitudinal population-based study in Canada of Peripherally Inserted Central Catheters (PICCs) noted the catheters were locked with heparin and a neutral needleless connector was used. Occlusion was noted as the most frequent complication with 3.4 occlusions per 1000 catheter days (7)
• A retrospective, haematology oncology cohort study of 51 Tunnelled-Cuffed Centrally Inserted Central Catheters (tc-CICC) with a positive needleless connector, locked unused devices once per week with sodium chloride. Results were 27% of tc-CICC had one occlusion and 4% were a complete occlusion and 23% were partial (8).

1.2 Practice Recommendation

CNSA recommendations for needleless connectors use with Peripheral Intravenous Cannulas (PIVCs) and Central Venous Access Devices (CVADs) include:

1. Needleless connector design is taken into consideration for selection of the most appropriate device including:

   • septum surface – smooth and flat to facilitate thorough disinfection

   • septum seal – tight fit with no gaps between the septum and its housing

   • fluid pathway - direct and straight to facilitate flushing and removal of debris

   • dead space – or areas that cannot be flushed effectively

   • internal mechanism - not torturous and simple with no moving parts

   • clamping sequence – not required or only one technique with one type of NC

   • visibility – transparent housing to aid in visualisation of clean fluid pathway

   • blood reflux – little or no blood reflux into the tip with a luer access mechanism

   • flushing solution – locking with sodium chloride

2. Every clinician and patient, family/carer uses the appropriate clamping-disconnection technique for the type of needleless connector used in their healthcare organisation including (1,9):

   • Negative needleless connectors: clamp the catheter or extension tubing (for Totally Implanted Venous Access Devices and Peripheral Intravenous Cannulas) PRIOR to finishing the flush and disconnection of the syringe.

   • Positive needleless connectors: clamp the catheter or extension tubing (for Totally Implanted Venous Access Devices and PIVCs) should be clamped AFTER finishing the flush and disconnection of the syringe.

   • Neutral needleless connectors: no specific clamping sequence at the end of flushing or locking is required.

   • Anti-reflux needleless connectors or bidirectional needleless connectors: no specific clamping sequence is required.

3. A healthcare organisation uses one type of needleless connector (negative, positive, neutral or anti-reflux) that requires the same clamp-disconnection technique, ensure all personnel involved with CVAD and PIVC management are educated and is detailed in organisational policy (4,9).

4. A needleless connector is attached to each lumen to create a closed system to reduce the risk of CVAD related infections (3).

5. Frequency of changing needleless connectors include:

   • Inpatients: check with manufacturers guidelines or every 7 days to align with the principle of a closed system (3)

   • Outpatient/ambulatory patients: every 7 days to align with dressing changes

   • Or earlier if contaminated with residual blood, drug or precipitates or other residues (1)

   • Prior to blood cultures from a CVAD as needleless connectors are a common source of infection when needleless connector disinfection is inadequate (1)

6. Ensure needleless connectors use a luer lock design to attach to a catheter hub, extension tubing on a huber needle or Peripheral Intravenous Cannula hub (1,9)

CNSA suggests considering using needleless connectors with bi-directional needleless connectors to reduce the risk of occlusions in with Central Venous Access Devices (CVADs) for paediatric and adult patients with cancer (5,6). Bi-directional needleless connectors are not currently cost-effective for use with PIVC.

Assess the features of the needleless connector in use in your organisation according to the nine features detailed by Jarvis, 2010.

CNSA strongly recommends the disinfection of the needleless connector prior to every access, for every PIVC and CVAD, for every patient (1,9-11) Refer to flushing page

CNSA strongly recommends the documentation of needleless connector replacement (1,9-11).

GRADE: Committee Consensus

1. Gorski L, Hadaway L, Hagle ME, McGoldrick M, Orr M, Doellman D. Infusion therapy: standards of practice. Journal of Infusion Nursing. 2016;39(1S):S1-S159.

2. Cope DG, Elledge CM, Thompson Mackey H, Moran AB, Rogers MA, Schulmeister L, et al. Access Device Standards of Practice for Oncology Nursing. Society ON, editor. Pittsburgh, Pennsylvania: Oncology Nurses Society.; 2017.

3. O'Grady NP, Alexander M, Burns LA, Dellinger EP, Garland J, Heard SO, et al. Guidelines for the Prevention of Intravascular Catheter-Related Infections. American Journal of Infection Control. 2011;39(4, Supplement):S1-S34.

4. Jarvis WR. Choosing the Best Design for Intravenous Needleless Connectors to Prevent Bloodstream Infections Infection Control Today2010 [2020]. Available from: https://www.infectioncontroltoday.com/view/choosing-best-design-intravenous-needleless-connectors-prevent-bloodstream.

5. Hitchcock J. Preventing intraluminal occlusion in peripherally inserted central catheters. British Journal of Nursing. 2016;25(19):S12-S8.

6. Holt D, Lawrence S. The Influence of a Novel Needleless Valve on Central Venous Catheter Occlusions in Pediatric Patients. JAVA - Journal of the Association for Vascular Access. 2015;20(4):214-20.e2.

7. Borretta L, MacDonald T, Digout C, Smith N, Fernandez CV, Kulkarni K. Peripherally Inserted Central Catheters in Pediatric Oncology Patients: A 15-Year Population-based Review From Maritimes, Canada. J Pediatr Hematol Oncol. 2018;40(1):e55-e60.

8. Buchini S, Scarsini S, Montico M, Buzzetti R, Ronfani L, Decorti C. Management of central venous catheters in pediatric onco-hematology using 0.9% sodium chloride and positive-pressure-valve needleless connector. Eur J Oncol Nurs. 2014;18(4):393-6.

9. Canadian Vascular Access Association. Canadian Vascular Access and Infusion Therapy Guidelines. Pembroke, ON: Pappin Communications.; 2019.

10. Royal College of Nursing. Standards For Infusion Therapy. 4th ed. London2016.

11. Loveday HP, Wilson JA, Pratt RJ, Golsorkhi M, Tingle A, Bak A, et al. epic3: National Evidence-Based Guidelines for Preventing Healthcare-Associated Infections in NHS Hospitals in England. Journal of Hospital Infection. 2014;86:S1-S70.