LEADING ARTICLE

© 2004 The Medicine Publishing Company LtdiANAESTHESIA AND INTENSIVE CARE MEDICINE

Localization of the internal jugular vein (IJV) for central venous catheter (CVC) insertion is an area of intense debate. It has been estimated that about 200,000 central venous access procedures are performed annually in the NHS and most involve the placement of CVCs into the IJV in the perioperative/ICU setting. Although CVC insertion into the IJV is generally a safe procedure, there are important hazards, notably carotid arterial puncture and incorrect catheter placement, either of which may be serious in high-risk patients. Rarely, pneumothorax may occur, but it is more com-monly associated with subclavian vein puncture. For many years, localization of the IJV has been achieved using surface anatomical landmarks combined with palpation of the adjacent carotid artery. Some practitioners advocate palpating the vein itself. In experienced hands these traditional techniques are associated with carotid puncture rates of about 1.5–3%.1

There has been increasing interest in the use of two-dimensional (2D) ultrasound (US) in the placement of CVCs, particularly by the internal jugular route. Proponents of US cite its benefits in three circumstances:• patients with abnormal surface anatomy (e.g. obesity, previous

neck surgery)• high-risk patients (e.g. severe coagulopathy)• patients with normal surface anatomy but abnormal venous

anatomy (e.g. no vein).Because of the impossibility of identifying those patients with normal surface anatomy, but abnormal venous anatomy, propo-nents of US-guided CVC insertion have advocated its use in all circumstances. This has been facilitated by recent improvements in ultrasound technology that have resulted in more compact US machines, with improved image resolution at minimal increase in cost. A proposal for the routine use of US in CVC insertion was submitted to the National Institute for Clinical Excellence (NICE) in 2001. NICE commissioned a detailed assessment report, prepared by the School of Health and Related Research, University of Sheffield.2 In October 2002, NICE published their recommendations,3 with the ‘headline’ statement: ‘Two-dimensional imaging ultrasound guidance is recommended as the preferred method for insertion of central venous catheters into the internal jugular vein in adults and children in elective situations.’ This statement has been widely interpreted as a recommendation for universal use of 2D US and has caused great controversy, not least because it indicates a major change in practice for most practitioners inserting CVC lines. A number of objections to the NICE recommendations have been raised.• There is little evidence that US reduces the carotid puncture rate of expert operators inserting CVCs electively into the IJV of

adults. Of the 20 studies considered in the assessment report com-missioned by NICE only five are peer-reviewed reports that apply to this situation. Given that the incidence of carotid puncture in this situation using traditional techniques can be 1.5–3%, there is no doubt that the standards of ‘landmark’ insertion in these papers are poor, casting doubt on their applicability to experts in the technique.• The only published audit of the use of US in routine practice,4 gathered in a centre where US-guided CVC insertion is actively promoted, showed an incidence of carotid puncture of 5.8% (371 patients studied). The expectation that widespread use of US will lower the carotid puncture rate may well be optimistic.• The guidelines acknowledge the importance of maintaining traditional insertion techniques for use in the emergency situa-tion. However, there is little advice on how this is to be achieved, given the concern of some clinicians about the medico-legal con-sequences of not adhering to the NICE recommendations.• The NICE committee does not include any anaesthetists or inten-sivists; the two specialties responsible for most CVC insertions.• Widespread introduction of US-guided CVC insertion is esti-mated to cost the NHS £30 million in the first year following the NICE guidelines (according to the assessment report). Where does this leave practitioners? For those adept in tradi-tional methods of CVC insertion, the medico-legal concerns of flouting NICE guidelines are probably overstated, as summarized in a recent editorial written by an authority in medical negligence.5 The supporting statement from the Royal College of Anaesthet-ists that ‘the landmark method is still an acceptable alternative, whether or not 2D ultrasound is available’, is also important. With regard to training, the ideal situation would be for anaes-thetists to become skilled in both methods. US offers potential advantages for ‘difficult’ cases, whereas the traditional insertion techniques can be vital in emergency situations when US is un-available. Therefore, training should be structured with these goals in mind and should not be limited by medico-legal concerns. The evidence that US is universally beneficial in CVC insertion is incomplete, despite the statements from NICE. The argument in favour of routine use of US would benefit from more robust evidence showing a reduced carotid puncture rate at all levels of expertise. Until then the NICE recommendations will remain controversial.

REFERENCES1 McIlree N, Stenz R. Response to “Safe internal jugular cannulation”

J Cardiothorac Vasc Anesth 2002; 6(6): 790.

2 Calvert N, Hind D, McWilliams R G et al. The effectiveness and

cost-effectiveness of ultrasound locating devices for central venous

access. NHS R&D HTA Programme 2002.

3 NICE. Guidance on the use of ultrasound locating devices for placing

central venous catheters. National Institute for Clinical Excellence

Technology Appraisal Guidance 2002; 49.

4 Augoustides J G, Diaz D, Weiner J et al. Current practice of internal

jugular venous cannulation in a university anesthesia department:

Influence of operator experience on success of cannulation and

arterial injury. J Cardiothorac Vasc Anesth 2002; 16(5): 567–71.

5 Hart D. Some reflections on how not to get bitten by a clinical

guideline. Heart 2002; 87(6): 501–2.

Ultrasound for central venous access – the debateAlan Cohen

Consultant Cardiac Anaesthetist at the Bristol Royal Infirmary

la-cohen.indd i 17/12/03, 12:20:15