The Editorial Executive Committee welcomes letters, which should be less than 250 words. Before a decision to publish is made, letters which refer to a published article may be sent to the author for a response. Any letter may be sent to an expert for comment. When letters are published, they are usually accompanied in the same issue by their responses or comments. The Committee screens out discourteous, inaccurate or libellous statements. The letters are sub-edited before publication. Authors are required to declare any conflicts of interest. The Committee's decision on publication is final.


Letter to the editor

Editor, – In the article 'Controlling intravascular catheter infections' (Aust Prescr 2003;26:41-3), Table 2 states 'Routinely replace peripheral catheters within 48-72 hours...'.

The Centers for Disease Control in the USA found no evidence to support the routine changing of peripheral venous catheters. The 'Guidelines for the prevention of intravascular catheter-related infections' recommend: 'In adults replace catheter and rotate site no more frequently than every 72-96 hours. Replace catheters inserted under emergency basis and insert a new catheter at a different site within 48 hours. In pediatric patients, do not replace peripheral catheters unless clinically indicated.'1

Hospital bureaucracies frequently mandate routine changing of peripheral catheters within 72 hours, at the cost of great discomfort to patients and effort by resident medical officers. Given that routine changing of central lines has been shown to be unnecessary, and the daily infection risk quoted for peripheral cannulae is much lower than for central lines, it is also implausible that any benefit from routine changing of peripheral lines has been missed.

It would seem beneficial for Australian Prescriber to acquaint its readers with the evidence and discourage them from continuing what seems to be an unnecessary as well as painful custom.

Ian Woodforth


Mosman, NSW


Authors' comments

Dr Peter Collignon and Dr Robert Horvath, the authors of the article, comment:

The guidelines of the Centers for Disease Control (CDC) do recommend changes of peripheral lines after 72-96 hours rather than our suggested 48-72 hours. Our concern is that the CDC based the guidelines on the incidence of 'phlebitis', not bacteraemia. As phlebitis is thought to be usually due to non-infective causes (e.g. irritation from drugs), we do not believe it is an appropriate surrogate marker for bacteraemia.

If one examines bacteraemia caused by catheters, it becomes clear that there are almost no cases with catheters that are in place for 24 hours or less and sepsis is very uncommon if the catheters are in place for less than 48 hours.2,3,4The CDC guidelines still recommend routine replacement at 48 hours for 'emergency cannulas'. This is a vague definition and appears to take in our concerns.

In our experience children do not have peripheral cannulas for prolonged periods. Although there is no reason to believe that intravenous catheter sepsis will be different in children, we are unaware of any authority currently recommending routine replacement of peripheral catheters in children.

The problem with doing studies on peripheral catheter sepsis is the very low incidence of bacteraemia (about one episode for every 3000 catheters).5A prospective randomised study would have to be extremely large and is therefore unlikely to be done. However, we believe that the evidence on bacteraemia (rather than phlebitis) strongly suggests that routine replacement of catheters at 48-72 hours will result in lower sepsis rates than replacement at later times.


Ian Woodforth


Dr Peter Collignon

Dr Robert Horvath