Adjacent central venous catheters can result in immediate aspiration of infused drugs during renal replacement therapy.

Dual-lumen haemodiafiltration catheters enable continuous renal replacement therapy in the critically ill and are often co-located with central venous catheters used to infuse drugs. The extent to which infusions are immediately aspirated by an adjacent haemodiafiltration catheter remains unknown. A bench model was constructed to evaluate this effect. A central venous catheter and a haemodiafiltration catheter were inserted into a simulated central vein and flow generated using centrifugal pumps within the simulated vein and haemodiafiltration circuit. Ink was used as a visual tracer and creatinine solution as a quantifiable tracer. Tracers were completely aspirated by the haemodiafiltration catheter unless the infusion was at least 1 cm downstream to the arterial port. No tracer was aspirated from catheters infusing at least 2 cm downstream. Orientation of side ports did not affect tracer elimination. Co-location of central venous and haemodiafiltration catheters may lead to complete aspiration of infusions into the haemodiafilter with resultant drug under-dosing.

Effect of the implementation of NICE guidelines for ultrasound guidance on the complication rates associated with central venous catheter placement in patients presenting for routine surgery in a tertiary referral centre.

BACKGROUND: The National Institute for Clinical Excellence (NICE) guidelines of 2002 recommended the use of ultrasound (US) for central venous catheterization in order to minimize complications associated with central line placement. An ongoing audit of line placement by anaesthetists in the theatre complex of a tertiary referral centre looked at the associated complication rates. The objective of the study was to compare complication rates pre- and post-implementation of NICE guidelines. METHODS: This prospective, single centre audit looked at all patients in whom a central venous catheter was placed for surgery. Complication rates were assessed for procedures that were performed pre- and post-implementation of NICE guidelines. In total, 438 patients were identified for the study, and the procedures were performed either by trainee or by consultant anaesthetists. RESULTS: The pre- and post-implementation complication rates were 10.5% (16/152) and 4.6% (13/284), respectively, representing an absolute risk reduction of 5.9% (95% CI 0.5-11.3%). Comparison of those procedures in which US was used when compared with the landmark technique after implementation found a reduction of 6.9% in complications (95% CI 1.4-12.4%). The reduction in complication rates was larger for specialist registrars than for consultants (11.2% vs 1.6%). CONCLUSIONS: The implementation of NICE guidelines has been associated with a significant reduction in complication rates in our tertiary referral centre. In the light of the cross-speciality evidence of US superiority and our results, it is imperative that routine use of US guidance becomes more widespread.