Central venous cathetersBMJ 2013; 347 doi: https://doi.org/10.1136/bmj.f6570 (Published 11 November 2013) Cite this as: BMJ 2013;347:f6570
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As the authors state, central venous catheter related blood stream infections are associated with significant morbidity and mortality. In addition to the bundle of interventions recommended by the Michigan group we use a three point fixation technique for all internal jugular cannulae. This followed the observation that the weight of the multiple lumens and stop cocks in catheters placed in this position drags the dressing away from the skin when the sits up. The entry site is then exposed , leaving the potential for extra luminal colonisation and infection.
The technique is simple (Figure 1). In addition to the two sutures placed at the hub site of a multi lumen catheter, a third suture is inserted as proximally as practical, gathering within it the multiple lumens. A skin bridge of at least one centimetre ensures the suture does not pull through with the weight of the lumens. If a pulmonary artery catheter introducer is inserted, the additional suture is inserted laterally on the side arm of the device. This additional suture ensures the dressing is much more stable and the entry site remains covered at all times. (Figure 2). When combined with the use of injection hubs on all ports in use, the three point suture technique resulted in a tenfold reduction in line colonisation.
These changes were implemented some 13 years ago and have become an institutional standard. Despite having one of the largest intensive care areas in the United Kingdom, our incidence of catheter related bacteraemias varies between 0 and 0.7 per thousand catheter days and consistently lower than the Michigan standard.
We recommend the three point fixation as a simple and highly effective addition to the precautions quoted in the article for reducing catheter related infections, particularly when the internal jugular approach is used.
Competing interests: No competing interests
Smith and Nolan (2013) provide a comprehensive and thorough article on the insertion, care and prevention of complications with regard to central venous catheters. We believe this article will have a sustained impact in view of the range and accuracy of its content.
With regard to the prevention of infective complications, a number of strategies are described. However, we would like to share our experience of additional interventions we have implemented across our 500-bedded district general hospital. We have a dedicated vascular access team lead by a consultant nurse. The team offer a trust-wide vascular access service (Jackson 2007). A significant proportion of the team’s responsibilities is to ensure the organisation is working towards zero line infections. These interventions can be summarised as follows:
The team promote the optimal use of an appropriate anatomical site for central venous catheter placement. Sixty-eight percent of devices are arm placed. Jugular and subclavian devices comprise twenty-six percent of the devices placed. Finally, four percent of the devices are femoral and two percent are tunnelled. The site selected for placement is imperative; when we consider the pathogenesis of central line infections it is suggested that sixty percent of infections may originate from skin organisms (Safdar and Maki 2004). However, certain areas will have a greater number of colony forming units and particular sites may be difficult to manage.
We also complete a preventative surveillance programme that ensures a daily patient review is completed. The purpose of the review is the early identification of potential risk factors for central line contamination that may lead to bacteraemia. Also, if an infection is suspected optimal investigations, management and appropriate multi-disciplinary root cause analysis and review are completed. Regular monitoring ensures accurate performance reporting of central line infections at Infection Prevention and Control Committee and Trust Board levels.
Current central line associated bloodstream infection rate for the organisation is 0.2 per thousand catheter days. The team ensure professional expectations; product, practice and education are integrated across the organisation. Also, our approach to vascular access and infection prevention has demonstrated that zero central line infections can be achieved (Jackson and Cooper 2012).
We recommend your readers must not underestimate the impact of investing in vascular access and infection prevention. Billett et al. (2013) suggest infection prevention programmes can result in the avoidance of an estimated 2964 line infections, with a monetary saving of $103,722,423.00 and a staggering 355 lives saved.
Billett, A.L., Colletti, R.B., Mandel, K.E., Miller, M., Muething, S.E., Sharek, P.J. and Lannon, C.M. (2013) Exemplar pediatric collaborative improvement networks: achieving results. Pediatrics. 131 Supplement 4:S196-203.
Jackson, A. (2007) Development of a trust-wide vascular access team. This is an extended [online] version of the article published in Nursing Times. 103(44), p.28-29. Last accessed 20th September 2013 at: http://www.nursingtimes.net/development-of-a-trust-wide-vascular-access-...
Jackson, A. and Cooper, S. (2012) Zero central-line infections in a 550-bedded district general hospital. British Journal of Nursing. 21(14), supplement p.S24–S28.
Safdar, N. and Maki, D.G. (2004) The pathogenesis of catheter-related bloodstream infection with noncuffed short-term central venous catheters. Intensive Care Medicine. 30(1), p.62-67.
Smith, R.N. and Nolan, J.P. (2013) Central venous catheters. BMJ. 347:f6570.
Competing interests: No competing interests
The overview of central venous catheters (CVC) by Smith and Nolan correctly states that antiseptic or antimicrobial impregnation reduces the risk of CVC-bloodstream infection (BSI).1 This has been confirmed in at least 12 systematic reviews and 56 randomised controlled trials.2 The dilemma for clinicians however, is which types of impregnation work best and for whom.
Smith and Nolan refer to a recent Cochrane systematic review, but this did not address which type of impregnation is most effective as there were few head to head studies. The best available evidence on the relative effects of different types of impregnation comes from a network meta-analysis by Wang et al.3 This study concluded that rifampicin-minocycline impregnated CVCs and heparin-bonded CVCs were most effective for reducing catheter-related BSI.
To address the question of “effective for whom?”, we need to address strong arguments that some populations are so physiologically different, that the large number of trials done so far in adults do not apply. For example, the arguments used to support the funding application of the CATCH trial, a 3-arm trial of heparin-bonded or rifampicin-minocycline CVCs versus standard CVCs in children in paediatric intensive care, were that small catheter lumens are associated with high rates of thrombosis, which might override antimicrobial effects of impregnation. We also argued that the introduction of CVC insertion and maintenance bundles may reduce or remove the effect. The study is due to report in 2014 (www.catchtrial.org.uk).
Another aspect of the question “effective for whom?” relates to the patient’s baseline risk of BSI. Smith and Nolan cite new guidelines that recommend using impregnated CVCs only in patients who need a catheter for more than 5 days or in units where rates of BSI are high. Yet a UK cost effectiveness study calculated that impregnated CVCs are cost effective even at BSI rates as low as 0.2%.4 This suggests that impregnated CVCs would be cost effective across all intensive care settings, even those with effective CVC infection reduction programmes in place.
The puzzle is why, despite the accumulation of randomised controlled studies showing a substantial beneficial effect of CVC impregnation for reducing a serious adverse outcome (BSI), there has been limited uptake in the NHS and a lack of support from national guidance. What further evidence is needed? More head to head trials would be helpful to provide direct evidence on which type of impregnation is most effective for reducing BSI. As for other outcomes, catheter colonisation is a biased and clinically irrelevant outcome.5 We also argue for caution in interpreting effects on sepsis or all-cause mortality. These outcomes would be expected to be attenuated by early detection and intensive interventions in the critical care setting, thereby biasing towards a null effect.
What we need to understand most is why clinicians and guideline writers are so reluctant to adopt impregnated CVCs. The answers may help to make future evaluation and implementation of new devices more efficient.
1. Smith RN, Nolan JP. Central venous catheters. BMJ 2013;347.
2. Lai NM, Chaiyakunapruk N, Lai NA, O'Riordan E, Pau WSC, Saint S. Catheter impregnation, coating or bonding for reducing central venous catheter-related infections in adults. Cochrane Database Syst Rev 2013;6:CD007878.
3. Wang H, Huang T, Jing J, Jin J, Wang P, Yang M, et al. Effectiveness of different central venous catheters for catheter-related infections: a network meta-analysis. J Hosp Infect 2010;76(1):1-11.
4. Hockenhull J, Dwan K, Boland A, Smith G, Bagust A, Dündar Y, et al. The clinical effectiveness and cost-effectiveness of central venous catheters treated with anti-infective agents in preventing bloodstream infections: a systematic review and economic evaluation. Health Technol Assess Rep 2008;12(12):1-154.
5. Geffers C, Zuschneid I, Eckmanns T, Rüden H, Gastmeier P. The relationship between methodological trial quality and the effects of impregnated central venous catheters. Intens Care Med 2003;29(3):403-09.
Competing interests: The authors are members of the CATCH trial team (NIHR HTA project number 08/13/47).
I read with interest the recent article relating to central line insertion. It seems clear that ultrasound provides improved visualisation of the central veins and also cannulation success rates. I do however believe that it can lead to a degree of complacency with regards to patient positioning.
Ultrasound guidance is of great benefit when cannulating the internal jugular veins but can easily be complicated by positioning. For example, if the patient is positioned with too much cervical rotation this can produce images where the vein appears to directly overlie the carotid artery, potentially complicating the procedure from a practical perspective.
Ultrasound is a user dependent imaging modality. This requires learning 2 skills at once if this is the first exposure to ultrasound use.
Whilst I do not disagree that ultrasound is of benefit in improving success rate and reducing complications more emphasis needs to be put on teaching the basics of line insertion and in particular patient positioning and awareness of the basic anatomy.
1. Ninfa Mehta, Walter Wallace Valesky, Allysia Guy, Richard Sinert. Is Real-time Ultrasonic-Guided Central Line Placement by ED Physicians More Successful Than the Traditional Landmark Approach? Emerg Med J. 2013;30(5):355-359.
Competing interests: No competing interests