Guidelines & recommendations for the use of lock solutions

How do you know which lock solution to choose for which patient? In order to make an informed decision, medical professionals rely on different types of sources: 

1. Clinical studies 
2. Meta-analyses and reviews 
3. Guidelines and recommendations 

For the latter, we have seen a lot of updates since TauroLock™ first entered the market in 2004. From endorsements of antimicrobial locks to specific mentions of taurolidine and urokinase: These are the most important guidelines to date. 

Antimicrobial lock solutions 

Until the early 2000s, lock solutions were used primarily to maintain patency in dialysis. But this approach did not take into account another significant risk: catheter-related infections. Gradually, experts recognised that strict hygiene standards alone are not enough. They began to demand the preventive use of antimicrobial lock solutions. This shift is reflected in numerous guidelines.  

Position statement of European Renal Best Practice 2010 (ERBP) 

The preventive use of antimicrobial locks is advocated to reduce the rate of CRBSI. [1] 

CDC Guidelines for the Prevention of Intravascular Catheter-related Infections 2011 

Use prophylactic antimicrobial lock solution in patients with long term catheters who have a history of multiple CRBSI despite optimal maximal adherence to aseptic technique... [2] 

Infusion Therapy Standards of Practice 2024 (INS) 

Use antimicrobial locking solutions for therapeutic and prophylactic purposes in patients with long-term CVADs in the following circumstances: patients with a history of multiple CABSIs, high-risk patient populations, and in facilities with unacceptably high rates of CLABSI, despite implementation of other methods of infection prevention... [3] 

Active ingredients 

As illustrated above, many guidelines recommend the use of antimicrobial lock solutions. But what kind of lock solution, exactly? Which active ingredients have proven most effective for which purpose? Taurolidine and urokinase have moved at the forefront in recent publications. 

Taurolidine 

Taurolidine is derived from taurine, an amino acid that naturally occurs in the human body. It has a strong activity against a broad range of bacteria and fungi, as demonstrated in numerous publications in the last few decades. Recent studies have shown that taurolidine can even eradicate mature biofilm and pathogens resistant to antibiotics. [25,26] Based on these findings, it is now widely used as an active ingredient for antimicrobial lock solutions.  

Guideline of the French Society for Hospital Hygiene 2012 (SF2H)  

Should an antibacterial lock solution be indicated, taurolidine or any other compound with proven efficacy in preventing catheter-infections should be preferentially used... [4]  

(Translated from French) 

GAVeCeLT consensus 2016 

…the most appropriate lock solution for infection prevention should include citrate and/or taurolidine, which have both anti-bacterial and anti-biofilm activity, with negligible undesired effects if compared to antibiotics… [5] 

Guideline of the Commission for Hospital Hygiene and Infection Prevention 2017 (KRINKO) 

3.11.6: In case of patients with not only temporary (e.g. postoperative) cyclical parenteral nutrition over a conventional, non-tunnelled CVC the intermittent blocking with taurolidine or ethanol may be considered... [6] 

(Translated from German) 

Guideline of the German Society for Applied Hygiene in Dialysis 2022 (DGfaHD) 

The frequency of catheter-related infections is reduced significantly when using antimicrobially active lock solutions in comparison to heparin or 4 % citrate, in case of low as well as excessive infection rates. Expert associations / KRINKO therefore recommend using antimicrobial lock solutions. Meta-analyses confirm the efficacy of citrate solutions supplemented by additional antimicrobial ingredients (e.g. taurolidine). [7] 

(Translated from German) 

Urokinase 

To maintain patency, medical staff commonly rely on anticoagulants such as heparin and citrate. While these active ingredients prevent occlusion, they are not helpful when the catheter has already been obstructed. In those cases, more and more experts recommend using thrombolytics that can break up blood clotting in early stages.  

NKF/KDOQI guidelines 2000 

Thrombosis of catheter lumens is the most common cause of catheter dysfunction. The urokinase protocol is successful in resolving the thrombus in 70% to 90% of instances. This protocol should be attempted as the first procedure to resolve catheter thrombosis because it is the least invasive and least costly of all catheter salvage techniques. [8] 

Recommendation of German expert panel 2009 

Efficiency of the catheter has to be controlled to detect malfunction of the device (e.g. Flow rate, recirculation, Kt/V). To prevent occlusion it can be considered to apply a periodical local fibrinolytic treatment of the catheter using urokinase or rTPA as lock solution or for continuous infusion. [9] 

(Translated from German) 

Guideline of the German Society for Applied Hygiene in Dialysis 2022 (DGfaHD) 

With regard to maintenance of patency, current research has shown a superiority of fibrinolytics (rt-PA, urokinase) over the ingredients heparin and citrate when used once a week. Malfunction rates are reduced significantly in comparison to heparin (5,000 IU/ml) and citrate (4 %). [7] 

(Translated from German) 

Dutch guideline for vascular access in haemodialysis 2022 (FMS) 

Consider adding thrombolytics to the catheter lock once a week (1 mg alteplase per lumen or 5,000 IU/ml urokinase; KDOQI 2019 update, recommendation 21.6), as this reduced flow dysfunction and bloodstream infections by approximately 50 % in randomised studies. [10] 

(Translated from Dutch) 

Guideline of the Society for Paediatric Oncology and Haematology 2018 (GPOH) 

23.6.4 Urokinase lock as adjuvant therapy 

Results of in-vitro experiments, studies on prophylaxis, and observational studies support the adjuvant use of urokinase for gram-positive catheter infections since these are often associated with blood clotting within the CVAD (Cat. II). [11] 

(Translated from German) 

Fields of application 

Each patient has individual needs and challenges. What might yield excellent results in one patient might cause dangerous side effects in another. Therefore, lock solutions must be carefully selected on a case-by-case basis. Here’s an overview of guidelines that specify the requirements for lock solutions in different fields of application.  

Dialysis 

In haemodialysis, central-venous catheters (CVC) serve as the vessel for the patient’s blood running out of their body through the machine and back into the body. This process inevitably comes with a high risk of blood clotting within the catheter lumen. Therefore, a lock solution must protect patients not only against infectious germs, but also against the formation of fibrin that might otherwise lead to occlusion. National and international guidelines have issued recommendations for both criteria.  

Dialysis – infection prevention 

Position statement of European Renal Best Practice 2010 (ERBP) 

Recommendation B.3.1: The preventive use of antimicrobial locks is advocated to reduce the rate of CRBSI. [1] 

Australian guidelines for haemodialysis 2015 (NHMRC) 

Taurolidine has been found to: 

• have a very broad-spectrum antimicrobial activity 

• decrease development of biofilms 

• be associated with a reduced CRBSI rate compared to heparin [12] 

Spanish Clinical Guidelines on Vascular Access for Haemodialysis 2017 (SEN) 

CVC lock with antiseptics, such as taurolidine, ethanol or the combination of citrate with methylene blue-parabens or with taurolidine and heparin, have shown efficacy against the bacterial biofilm and in CRB prophylaxis. These substances would have the advantage of preventing possible induction of resistance to antibiotics... [13] 

Brazilian guidelines 2017 (ANVS)  

It is recommended to use a substance with antimicrobial properties such as ethanol or taurolidine, which does not fall into the category of antibiotics/ antifungals... [14] 

(Translated from Portuguese) 

Guideline for infection prevention and hygiene 2019 (DGfN) 

Blocking with antibacterial lock solutions may be part of measures against overly high bloodstream infections in catheter patients (Cat. IB)…taurolidine and gentamicin exert only antimicrobial effectiveness…Citrate solutions show…– in higher concentrations – at least partial antimicrobial properties, which is – however – insufficient against Staph. aureus. [15] 

(Translated from German) 

Guideline of the German Society for Applied Hygiene in Dialysis 2022 (DGfaHD) 

The frequency of catheter-related infections is reduced significantly when using antimicrobially active lock solutions in comparison to heparin or 4 % citrate, in case of low as well as excessive infection rates. Expert associations / KRINKO therefore recommend using antimicrobial lock solutions. Meta-analyses confirm the efficacy of citrate solutions supplemented by additional antimicrobial ingredients (e.g. taurolidine). [7] 

(Translated from German) 

Dutch guideline for vascular access in haemodialysis 2022 (FMS) 

Therefore, preferably use a catheter lock containing citrate 4% or heparin 5000 IU/mL (KDOQI 2019 Update, recommendation 21.4). [10] 

(Translated from Dutch) 

Dialysis standard of the German Society of Nephrology 2022 (DGfN) 

Between dialysis treatments, the central-venous access device may be blocked using a diluted heparin solution. Heparin, however, does not have any antibacterial properties. Antibacterial lock solutions should therefore be preferred since they reduce the rate of catheter-related bacteraemias considerably. The use of antibiotics is not recommended due to the potential development of resistance. Alternatively, citrate in various concentrations (4%, 30% or 46%) or taurolidine-citrate solutions may be used. Due to the risk of severe cardiac arrhythmias, highly concentrated citrate must be strictly administered by trained staff according to the instructions of the manufacturer. 4% citrate-solutions have proven effective at lower risk of complications and are currently broadly accepted as a standard within citrate solutions. [16] 

(Translated from German) 

Dialysis – patency  

Guideline of the German Society for Applied Hygiene in Dialysis 2022 (DGfaHD) 

…With regard to maintenance of patency, current research has shown a superiority of fibrinolytics (rt-PA, urokinase) over the ingredients heparin and citrate when used once a week. Malfunction rates are reduced significantly in comparison to heparin (5,000 IU/ml) and citrate (4 %).  [7] 

(Translated from German) 

Dutch guideline for vascular access in haemodialysis 2022 (FMS) 

Therefore, preferably use a catheter lock containing citrate 4% or heparin 5000 IU/mL (KDOQI 2019 Update, recommendation 21.4). 

Consider adding thrombolytics to the catheter lock once a week (1 mg alteplase per lumen or 5,000 IU/ml urokinase; KDOQI 2019 update, recommendation 21.6), as this reduced flow dysfunction and bloodstream infections by approximately 50 % in randomised studies. [10] 

(Translated from Dutch) 

Guideline for infection prevention and hygiene 2019 (DGfN) 

An additional option is the intermittent (once weekly) use of urokinase in the lock solution... [15] 

(Translated from German) 

Parenteral nutrition 

In parenteral nutrition (PN), CVCs serve to administer nutrients directly into the patient’s bloodstream. These access systems can easily be colonised by pathogens that might cause potentially life-threatening infections. Moreover, parenteral nutrition may run continuously for several hours every day. This means that the lock solution remains within the catheter for a relatively short time and must come into effect rather quickly. According to a large number of expert panels, taurolidine is now the best choice to meet these requirements. Respective guidelines commonly refer to oncological patients as well because these depend on PN in many cases.  

Government of Western Australia 2018 

• TauroLock™-HEP100 can be used instead of standard heparin-saline lock solutions in children with CVADs inserted who are at increased risk of CLABSI. 

• TauroLock™-HEP100 may be commenced upon insertion of a new CVAD (preferable) or commenced in a child with an existing CVAD. 

•  TauroLock™-HEP100 requires a minimum dwell time of 2 hours with administration only occurring once in 24 hours. [17] 

ESPGHAN/ESPEN/ESPR/CSPEN guidelines 2018 

Taurolidine is effective in preventing CRBSI and should be used during long term catheter use. [18] 

Guidelines of the Society for Paediatric Gastroenterology and Nutrition 2022 (GPGE) 

Due to the ability to prevent the formation of biofilms, the Working Group recommends using taurolidine-based catheter lock solutions in all paediatric patients dependent on home parenteral nutrition with chronic intestinal failure. After the first reported CLABSI at the latest, taurolidine should be used daily as an antimicrobial catheter lock solution in accordance with current guidelines to prevent further infections. ... citrate can reduce catheter occlusions because of its anticoagulant properties when combined with taurolidine ... which is preferred instead of a pure taurolidine lock. [19] 

(Translated from German) 

ESPEN guideline 2020 

As an additional strategy to prevent CRBSIs, taurolidine locking should be used because of its favorable safety and cost profile. [20] 

ESPEN practical guideline 2021 

We suggest that catheter locking with taurolidine may be used to prevent CRI. [21] 

Infusion Therapy Standards of Practice 2024 (INS) 

Taurolidine was effective in prevention of catheter-related bloodstream infections (CRBSIs) for patients on HPN and...considered generally safe. [3] 

Guideline of the German Society for Nutritional Medicine 2024 (DGEM) 

Taurolidine-based lock solutions should be used to reduce the risk of CRBSI in patients at high risk; in patients at normal risk, they should be used as an additional strategy to prevent CRBSI. [22] 

(Translated from German)

Oncology  

Guidelines for the use of lock solutions in oncology also include haematology and parenteral nutrition. Patients undergoing these treatments are particularly vulnerable: In addition to a weakened immune system, they have an increased high risk of developing infections from their CVCs. Experts therefore recommend taurolidine (in combination with other active ingredients) for the most effective prophylaxis. 

Government of Western Australia 2018 

• TauroLock™-HEP100 can be used instead of standard heparin-saline lock solutions in children with CVADs inserted who are at increased risk of CLABSI. 

• TauroLock™-HEP100 may be commenced upon insertion of a new CVAD (preferable) or commenced in a child with an existing CVAD. 

• TauroLock™-HEP100 requires a minimum dwell time of 2 hours with administration only occurring once in 24 hours. [17] 

Guideline of the Society for Paediatric Oncology and Haematology 2018 (GPOH) 

23.6.3 Taurolidine lock for adjuvant therapy 

Taurolidine (e.g. 1.35 % taurolidine, 4 % citrate) can be used as an adjuvant measure during systemic treatment with antibiotics (Cat. II). The minimal dwell time in the catheter lumen is 4 hours. 

 23.6.4 Urokinase lock as adjuvant therapy 

Results of in-vitro experiments, studies on prophylaxis, and observational studies support the adjuvant use of urokinase for gram-positive catheter infections since these are often associated with blood clotting within the CVAD (Cat. II). [11] 

(Translated from German) 

Guideline of the French Society for Clinical Nutrition and Metabolism 2019 (SFNCM) 

For patients, adults and children, receiving a short- or long-term parenteral nutrition 

Initiating the use of a lock solution based on taurolidine is recommended for secondary prevention, after the first central catheter infection. 

Moreover, several health organisations agree on the use of these lock solutions if the possibilities of central venous access are limited and the patient is at high risk of CRBSI. For patients with previous CRBSI, use of these lock solutions may be considered in a new catheter (primary prevention for the catheter, but secondary for the patient). [23] 

(Translated from French)  

Guidelines of the Italian Association of Pediatric Hematology and Oncology 2022 (AIEOP) 

Locking with non-antibiotic antibacterial substances (in particular, 2% taurolidine) has been proven effective in pediatric patients in reducing the risk of infection. ....(BI) 

The use of thrombolytic substances (urokinase 5000 IU/ml or the tissue activator of plasminogen - rTPA 1 mg/ml) is recommended only in case of occlusion of the catheter lumen due to clots. [24] 

Intensive care 

In intensive care units (ICU), a CVC can turn into the patient’s literal lifeline. The time windows in-between treatments are extremely short. Therefore, the lock solution has to exert a strong antimicrobial activity that takes effect as fast as possible. Guidelines for ICUs pertain to the fields of PN, oncology, and haematology.  

Guideline of the Commission for Hospital Hygiene and Infection Prevention 2017 (KRINKO) 

In case of patients with not only temporary (e.g. postoperative) cyclical parenteral nutrition over a conventional, non-tunnelled CVC the intermittent blocking with taurolidine or ethanol may be considered, if the necessary dwell time (taurolidine 4 h, ethanol 2 h) in the catheter lumen can be maintained (Category IB for taurolidine, Category II for ethanol). [6] 

(Translated from German)

Guideline of the Spanish Society of Intensive and Critical Care Medicine and Coronary Care Units 2022 (SEMICyUC) 

Currently, the locking of CVCs with taurolidine is taking on an important role in the prevention of CRBSI, especially in certain fields such as home parenteral nutrition and other patients at high risk of catheter infection (e.g. oncology patients). [27] 

(Translated from Spanish) 

Paediatric patients 

Several guidelines have established specific recommendations for lock solutions in children, infants, and even neonates. These patients need a particularly strong protection against catheter-related infections. 

Guideline of the Society for Paediatric Oncology and Haematology 2018 (GPOH) 

23.6.4 Urokinase lock as adjuvant therapy 

Results of in-vitro experiments, studies on prophylaxis, and observational studies support the adjuvant use of urokinase for gram-positive catheter infections since these are often associated with blood clotting within the CVAD (Cat. II). [11] 

(Translated from German) 

Government of Western Australia 2018 

• TauroLock™-HEP100 can be used instead of standard heparin-saline lock solutions in children with CVADs inserted who are at increased risk of CLABSI. 

• TauroLock™-HEP100 may be commenced upon insertion of a new CVAD (preferable) or commenced in a child with an existing CVAD. 

• TauroLock™-HEP100 requires a minimum dwell time of 2 hours with administration only occurring once in 24 hours. [17] 

Guideline of the French Society for Clinical Nutrition and Metabolism 2019 (SFNCM) 

For patients, adults and children, receiving a short- or long-term parenteral nutrition 

Initiating the use of a lock solution based on taurolidine is recommended for secondary prevention, after the first central catheter infection. 

Moreover, several health organisations agree on the use of these lock solutions if the possibilities of central venous access are limited and the patient is at high risk of CRBSI. For patients with previous CRBSI, use of these lock solutions may be considered in a new catheter (primary prevention for the catheter, but secondary for the patient). [23] 

(Translated from French) 

Guidelines of the Italian Association of Pediatric Hematology and Oncology 2022 (AIEOP) 

Locking with non-antibiotic antibacterial substances (in particular, 2% taurolidine) has been proven effective in pediatric patients in reducing the risk of infection. (BI) 

The use of thrombolytic substances (urokinase 5000 IU/ml or the tissue activator of plasminogen - rTPA 1 mg/ml) is recommended only in case of occlusion of the catheter lumen due to clots. [24] 

Guidelines of the Society for Paediatric Gastroenterology and Nutrition 2022 (GPGE) 

Due to the ability to prevent the formation of biofilms, the Working Group recommends using taurolidine-based catheter lock solutions in all paediatric patients dependent on home parenteral nutrition with chronic intestinal failure. After the first reported CLABSI at the latest, taurolidine should be used daily as an antimicrobial catheter lock solution in accordance with current guidelines to prevent further infections. ... citrate can reduce catheter occlusions because of its anticoagulant properties when combined with taurolidine ... which is preferred instead of a pure taurolidine lock. [19] 

(Translated from German) 

References 

1. Vanholder et al. NDT Plus 2010. DOI: 10.1093/ndtplus/sfq041 
2. O'Grady et al. / Healthcare Infection Control Practices Advisory Committee (HICPAC). Clin Infect Dis 2011. DOI: 10.1093/cid/cir138 
3. Nickel et al. J Infus Nurs 2024. DOI: 10.1097/NAN.0000000000000532 
4. Hygienes / French Society for Hospital Hygiene (Société française d'Hygiène Hospitalière, SF2H) 2012. 
5. Pittiruti et al. J Vasc Access 2016. DOI: 10.5301/jva.5000576 
6. Commission for Hospital Hygiene and Infection Prevention (Kommission für Krankenhaushygiene und Infektionsprävention, KRINKO) at Robert Koch Institute. Bundesgesundheitsblatt 2017. DOI: 10.1007/s00103-016-2487-4 
7. German Society for Applied Hygiene in Dialysis (Deutsche Gesellschaft für angewandte Hygiene in der Dialyse, DGfaHD) 2022. 
8. National Kidney Foundation (NKF) / Kidney Disease Outcomes Quality Initiative (KDOQI) 2000. 
9. Hollenbeck et al. Nephrologe 2009. DOI: 10.1055/s-0029-1220873  
10. Dutch Federation of Medical Specialists (Federatie van Medisch Specialisten) 2022. 
11. Simon et al. Society for Paediatric Oncology and Haematology (Gesellschaft für pädiatrische Onkologie und Hämatologie, GPOH) 2018. 
12. National Health and Medical Research Council (NHMRC) 2015. 
13. Ibeas et al. Journal of the Spanish Society of Nephrology (Sociedad Española de Nefrología, SEN) 2017. DOI: 10.1016/j.nefro.2017.11.004 
14. National Agency for Sanitary Surveillance (Agência Nacional de Vigilância Sanitária, ANVS) 2017. 
15. German Society of Nephrology (Deutsche Gesellschaft für Nephrologie, DGfN) 2019. 
16. German Society of Nephrology (Deutsche Gesellschaft für Nephrologie, DGfN) 2022. 
17. Government of Western Australia / Child and Adolescent Health Service 2018. 
18. Kolaček et al. / ESPGHAN/ESPEN/ESPR/CSPEN working group on pediatric parenteral nutrition. Clin Nutr. 2018. DOI: 10.1016/j.clnu.2018.06.952 
19. Chronic Intestinal Failure Working Group of the Society for Paediatric Gastroenterology and Nutrition (Gesellschaft für pädiatrische Gastroenterologie und Ernährung, GPGE) 2022.  
20. Pironi et al. Clin Nutr 2020. DOI: 10.1016/j.clnu.2020.03.005 
21. Cuerda et al. Clin Nutr 2021. DOI: 10.1016/j.clnu.2021.07.002 
22. Bischoff et al. Aktuell Ernahrungsmed 2024. DOI: 10.1055/a-2270-7667 
23. Schneider et al. French Society for Clinical Nutrition and Metabolism (Société Francophone Nutrition Clinique et Métabolisme, SFNCM) 2019. 
24. Cellini et al. J Vasc Access 2022. DOI: 10.1177/1129729820969309 
25. Visek et al. Nutrition 2023. DOI: 10.1016/j.nut.2023.112115 
26. Hogan et al. Antimicrob Agents Chemother 2016. DOI: 10.1128/AAC.02885-15 
27. Spanish Society of Intensive and Critical Care Medicine and Coronary Care Units (Sociedad Española de Medicina Intensiva Crítica y Unidades Coronarias, SEMICyUC) 2022.